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'''Borax''' (also referred to as '''sodium borate''', '''tincal''' <span class="noexcerpt">({{IPAc-en|ˈ|t|ɪ|ŋ|k|əl}})</span> and '''tincar''' <span class="noexcerpt">({{IPAc-en|ˈ|t|ɪ|ŋ|k|ər}})</span>) is a [[salt (chemistry)|salt]] ([[ion]]ic compound) normally encountered as a [[hydration (chemistry)|hydrated]] [[borate]] of [[sodium]], with the [[chemical formula]] {{chem2|Na2H20B4O17|auto=1}}.<ref name="NIMH.borax"/>{{efn|It is also written as {{chem2|Na2B4O7|auto=1}}·{{chem2|10H2O|auto=1}}, which shows that it is a decahydrated tetraborate.}} [[Borax (mineral)|Borax mineral]] is a crystalline [[borate mineral]] that occurs in only a few places worldwide in quantities that enable it to be mined economically.
'''Borax''' (also referred to as '''sodium borate''', '''tincal''' <span class="noexcerpt">({{IPAc-en|ˈ|t|ɪ|ŋ|k|əl}})</span> and '''tincar''' <span class="noexcerpt">({{IPAc-en|ˈ|t|ɪ|ŋ|k|ər}})</span>) is a [[salt (chemistry)|salt]] ([[ion]]ic compound) normally encountered as a [[hydration (chemistry)|hydrated]] [[borate]] of [[sodium]], with the [[chemical formula]] {{chem2|Na2H20B4O17|auto=1}}.<ref name="NIMH.borax"/>{{efn|It is also written as {{chem2|Na2B4O7|auto=1}}·{{chem2|10H2O|auto=1}}, which shows that it is a decahydrated tetraborate.}} [[Borax (mineral)|Borax mineral]] is a crystalline [[borate mineral]] that occurs in only a few places worldwide in quantities that enable it to be mined economically.


Borax can be dehydrated by heating into other forms with less [[water of hydration]]. The anhydrous form of borax can also be obtained from the decahydrate or other hydrates by heating and then grinding the resulting glasslike solid it into a powder. It is a white crystalline solid that dissolves in water to make a [[base (chemistry)|basic]] [[aqueous solution|solution]] due to the [[tetraborate]] [[anion]].
Borax can be dehydrated by heating into other forms with less [[water of hydration]]. The anhydrous form of borax can also be obtained from the decahydrate or other hydrates by heating and then grinding the resulting glasslike solid into a powder. It is a white crystalline solid that dissolves in water to make a [[base (chemistry)|basic]] [[aqueous solution|solution]] due to the [[tetraborate]] [[anion]].


Borax is commonly available in powder or granular form and has many industrial and household uses, including as a [[pesticide]], as a metal soldering [[flux (metallurgy)|flux]], as a component of [[glass]], [[Enamelled glass|enamel]], and [[glaze (pottery)|pottery glaze]]s, for [[tanning (leather)|tanning]] of skins and [[hide (skin)|hide]]s, for artificial aging of wood, as a [[Wood preservation|preservative against]] [[Wood-decay fungus|wood fungus]], as a [[food additive]], and as a pharmaceutic [[alkalizer]]. In chemical laboratories it is used as a [[buffer solution|buffering]] agent.<ref name="NIMH.borax"/><ref name=CompTox/>
Borax is commonly available in powder or granular form and has many industrial and household uses, including as a [[pesticide]], as a metal soldering [[flux (metallurgy)|flux]], as a component of [[glass]], [[Enamelled glass|enamel]], and [[glaze (pottery)|pottery glaze]]s, for [[tanning (leather)|tanning]] of skins and [[hide (skin)|hide]]s, for artificial aging of wood, as a [[Wood preservation|preservative against]] [[Wood-decay fungus|wood fungus]], as a [[food additive]], and as a pharmaceutic [[alkalizer]]. In chemical laboratories it is used as a [[buffer solution|buffering]] agent.<ref name="NIMH.borax"/><ref name=CompTox/>


The terms ''tincal'' and ''tincar'' refer to the naturally-occurring borax historically mined from dry lake beds in various parts of Asia.<ref name=amoz2004/>
The terms ''tincal'' and ''tincar'' refer to the naturally occurring borax historically mined from dry lake beds in various parts of Asia.<ref name=amoz2004/>


== History ==
== History ==
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== Etymology ==
== Etymology ==
The English word ''borax'' is Latinized: the [[Middle English]] form was {{Lang|enm|boras}}, from [[Old French]] {{Lang|fro|boras, bourras}}.<ref name="OED.borax">{{Cite OED|borax|16485735}}</ref> That may have been from [[Medieval Latin]] {{lang|la|baurach}} (another English spelling), {{lang|la|borac(-/um/em), borax}}, along with [[Spanish language|Spanish]] {{lang|es|borrax}} (> {{lang|es|borraj}}) and [[Italian language|Italian]] {{Lang|it|borrace}}, in the 9th century, and from [[Arabic]] ({{lang|ar|بورق}}){{Transliteration|ar|bawraq, būraq, bōraq}}, as mentioned for example in ''Kitab al-Tabikh'' of [[Ibn Sayyar al-Warraq]].<ref name="OED.borax"/><ref>{{cite dictionary|last=Wehr |first=Hans |authorlink=Hans Wehr |editor-first=J. Milton |editor-last=Cowan |dictionary=A Dictionary of Modern Written Arabic |title={{lang|ar|بورق|cat=no}} |url=https://ejtaal.net/aa/#hw4=113,ll=312,ls=5,la=386,sg=169,ha=68,br=145,pr=28,vi=86,mgf=124,mr=93,mn=119,aan=86,kz=188,uqq=39,ulq=419,uqa=62,uqw=189,umr=148,ums=108,umj=86,bdw=129,amr=84,asb=81,auh=239,dhq=69,mht=65,msb=33,tla=33,amj=75,ens=89,mis=1801
The English word ''borax'' and its previous [[Middle English|Middle]] form {{Lang|enm|boras}} is a Latinate loan from [[Old French]] {{Lang|fro|boras}} ~ {{Lang|fro|bourras}}<ref name="OED.borax">{{Cite OED|borax|16485735}}</ref> which may have been from [[Medieval Latin]] {{lang|la|baurach}} (another English spelling), {{lang|la|borac(-/um/em), borax}}, along with [[Spanish language|Spanish]] {{lang|es|borrax}} (> {{lang|es|borraj}}) and [[Italian language|Italian]] {{Lang|it|borrace}}, in the 9th century, and from [[Arabic]] {{lang|ar|بورق}} {{Transliteration|ar|bawraq}} ~ {{Transliteration|ar|būraq}} ~ {{Transliteration|ar|bōraq}} which is attested in [[Ibn Sayyar al-Warraq]]'s ''Kitāb al-Ṭabīkh'' among many examples,<ref name="OED.borax"/><ref>{{cite dictionary|last=Wehr |first=Hans |authorlink=Hans Wehr |editor-first=J. Milton |editor-last=Cowan |dictionary=A Dictionary of Modern Written Arabic |title={{lang|ar|بورق|cat=no}} |url=https://ejtaal.net/aa/#hw4=113,ll=312,ls=5,la=386,sg=169,ha=68,br=145,pr=28,vi=86,mgf=124,mr=93,mn=119,aan=86,kz=188,uqq=39,ulq=419,uqa=62,uqw=189,umr=148,ums=108,umj=86,bdw=129,amr=84,asb=81,auh=239,dhq=69,mht=65,msb=33,tla=33,amj=75,ens=89,mis=1801
|location=Ithaca, NY |publisher=Spoken Language Services |year=1979 |page=100 |edition=4th |isbn=0-87950-003-4}}</ref><ref>{{cite book |last1=Ibn Sayyār al-Warrāq |first1=al-Muẓaffar ibn Naṣr |editor1-last=Nasrallah |editor1-first=Nawal |editor1-link=Nawal  Nasrallah |title=Annals of the caliphs' kitchens: Ibn Sayyār al-Warrāq's tenth-century Baghdadi cookbook |date=2007 |publisher=Brill |isbn=978-90-04-15867-2 |page=1}}</ref>
|location=Ithaca, NY |publisher=Spoken Language Services |year=1979 |page=100 |edition=4th |isbn=0-87950-003-4}}</ref><ref>{{cite book |last1=Ibn Sayyār al-Warrāq |first1=al-Muẓaffar ibn Naṣr |editor1-last=Nasrallah |editor1-first=Nawal |editor1-link=Nawal  Nasrallah |title=Annals of the caliphs' kitchens: Ibn Sayyār al-Warrāq's tenth-century Baghdadi cookbook |date=2007 |publisher=Brill |isbn=978-90-04-15867-2 |page=1}}</ref> from Middle Persian bwlk' (bōrag), which yielded Persian {{lang|fa|بوره}} ''bure''.


The words ''tincal'' and ''tincar'' were adopted into [[English language|English]] in the 17th century from [[Malay language|Malay]] {{Lang|ms|tingkal}} and from [[Urdu language|Urdu]]/[[Persian language|Persian]]/[[Arabic language|Arabic]] {{script|Arab|تنکار}} {{Transliteration|ur|tinkār/tankār}}; thus the two forms in English. These all appear to be related to the [[Sanskrit language|Sanskrit]] {{Lang|sa|टांकण}} {{Transliteration|sa|ṭānkaṇa}}.<ref name=OED.tinkal/><ref name=ChemIn1976/>
The words ''tincal'' and ''tincar'' were adopted into [[English language|English]] in the 17th century from [[Malay language|Malay]] {{Lang|ms|tingkal}} and from [[Urdu language|Urdu]]/[[Persian language|Persian]]/[[Arabic language|Arabic]] {{script|Arab|تنکار}} {{Transliteration|ur|tinkār/tankār}}; thus the two forms in English. These all appear to be related to the [[Sanskrit language|Sanskrit]] {{Lang|sa|टांकण}} {{Transliteration|sa|ṭānkaṇa}}.<ref name=OED.tinkal/><ref name=ChemIn1976/>
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[[File:Borax-unit-cell-3D-balls.png|thumb|upright|left|The structure of borax according to [[X-ray crystallography]].]]
[[File:Borax-unit-cell-3D-balls.png|thumb|upright|left|The structure of borax according to [[X-ray crystallography]].]]


From a chemical perspective, borax contains the [B<sub>4</sub>O<sub>5</sub>(OH)<sub>4</sub>]<sup>2−</sup> ion. In this structure, there are two four-coordinate boron centers and two three-coordinate boron centers.
From a chemical perspective, borax contains the {{chem2|[B4O5(OH)4](2-)}} ion. In this structure, there are two four-coordinate boron centers and two three-coordinate boron centers.


It is a [[proton conductor]] at temperatures above 21&nbsp;°C. Conductivity is maximum along the ''b-''axis.<ref name=mari1962/>
It is a [[proton conductor]] at temperatures above {{convert|21|C|F}}. Conductivity is maximum along the ''b-''axis.<ref name=mari1962/>


Borax is also easily converted to [[boric acid]] and other [[borate]]s, which have many applications. Its reaction with hydrochloric acid to form boric acid is:
Borax is also easily converted to [[boric acid]] and other [[borate]]s, which have many applications. Its reaction with hydrochloric acid to form boric acid is:
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The term ''borax'' properly refers to the so-called "decahydrate" {{chem2|Na2B4O7*10H2O}}, but that name is not consistent with its structure. It is actually octahydrate. The [[anion]] is not [[tetraborate]] {{chem2|[B4O7](2-)}} but [[tetraborate|tetrahydroxy tetraborate]] {{chem2|[B4O5(OH)4](2-)}},<ref name=mari1962/> so the more correct formula should be {{chem2|Na2B4O5(OH)4*8H2O}}. However, the term may be applied also to the related compounds. Borax "pentahydrate" has the formula {{chem2|Na2B4O7*5H2O}}, which is actually a trihydrate {{chem2|Na2B4O5(OH)4*3H2O}}. It is a colorless solid with a density of 1.880&nbsp;kg/m<sup>3</sup> that crystallizes from water solutions above 60.8&nbsp;°C in the [[rhombohedral crystal system]]. It occurs naturally as the mineral [[tinkhanite]].<ref name=akgu2021/> It can be obtained by heating the "decahydrate" above 61&nbsp;°C.<ref name=sahin2002/> Borax "dihydrate" has the formula {{chem2|Na2B4O7*2H2O}}, which is actually anhydrous, with the correct formula {{chem2|Na2B4O5(OH)4}}. It can be obtained by heating the "decahydrate" or "pentahydrate" to above 116-120&nbsp;°C.<ref name=sahin2002/> Anhydrous borax is sodium tetraborate proper, with formula {{chem2|Na2B4O7}}. It can be obtained by heating any hydrate to 300&nbsp;°C.<ref name=sahin2002/> It has one amorphous (glassy) form and three crystalline forms – α, β, and γ, with melting points of 1015, 993 and 936 K respectively. α-{{chem2|Na2B4O7}} is the stable form.<ref name=sahin2002/>
The term ''borax'' properly refers to the so-called "decahydrate" {{chem2|Na2B4O7*10H2O}}, but that name is not consistent with its structure. It is actually octahydrate. The [[anion]] is not [[tetraborate]] {{chem2|[B4O7](2-)}} but [[tetraborate|tetrahydroxy tetraborate]] {{chem2|[B4O5(OH)4](2-)}},<ref name=mari1962/> so the more correct formula should be {{chem2|Na2B4O5(OH)4*8H2O}}. However, the term may be applied also to the related compounds. Borax "pentahydrate" has the formula {{chem2|Na2B4O7*5H2O}}, which is actually a trihydrate {{chem2|Na2B4O5(OH)4*3H2O}}. It is a colorless solid with a density of {{val|1.880|u=kg/m3}} that crystallizes from water solutions above {{convert|60.8|C|F}} in the [[rhombohedral crystal system]]. It occurs naturally as the mineral [[tinkhanite]].<ref name=akgu2021/> It can be obtained by heating the "decahydrate" above {{convert|61|C|F}}.<ref name=sahin2002/> Borax "dihydrate" has the formula {{chem2|Na2B4O7*2H2O}}, which is actually anhydrous, with the correct formula {{chem2|Na2B4O5(OH)4}}. It can be obtained by heating the "decahydrate" or "pentahydrate" to above {{convert|116-120|C|F}}.<ref name=sahin2002/> Anhydrous borax is sodium tetraborate proper, with formula {{chem2|Na2B4O7}}. It can be obtained by heating any hydrate to {{convert|300|C|F}}.<ref name=sahin2002/> It has one amorphous (glassy) form and three crystalline forms – α, β, and γ, with melting points of {{convert|1015|K}}, {{convert|993|K}} and {{convert|936|K}} respectively. {{chem2|α\-Na2B4O7}} is the stable form.<ref name=sahin2002/>


== Natural sources ==
== Natural sources ==
{{main|Borax (mineral)}}
{{main|Borax (mineral)}}
[[File:Borax ball.jpg|thumb|Borax "cottonball"]]
[[File:Borax ball.jpg|thumb|Borax "cottonball" {{explain|reason=This term isn't mentioned anywhere and it's unclear whether this is even a natural source from the caption, or how this isn't just a rock from the 1980s digital camera quality picture.|date=July 2025}}]]


Borax occurs naturally in [[evaporite]] deposits produced by the repeated evaporation of [[seasonal lake]]s. The most commercially important deposits are found in:  [[Boron, California]]; and [[Searles Lake]], [[California]]. Also, borax has been found at many other locations in the [[Southwestern United States]], the [[Atacama Desert]] in [[Chile]], newly discovered deposits in [[Bolivia]], and in [[Tibet]] and [[Romania]]. Borax can also be produced synthetically from other boron compounds.<ref>{{Cite web |title=Borax - The Chemical Company |url=https://thechemco.com/chemical/borax/ |access-date=2024-04-08 |website=thechemco.com |language=en-US}}</ref>
Borax occurs naturally in [[evaporite]] deposits produced by the repeated evaporation of [[seasonal lake]]s. The most commercially important deposits are found in:  [[Boron, California]]; and [[Searles Lake]], [[California]]. Also, borax has been found at many other locations in the [[Southwestern United States]], the [[Atacama Desert]] in [[Chile]], newly discovered deposits in [[Bolivia]], and in [[Tibet]] and [[Romania]]. Borax can also be produced synthetically from other boron compounds.<ref>{{Cite web |title=Borax - The Chemical Company |url=https://thechemco.com/chemical/borax/ |access-date=2024-04-08 |website=thechemco.com |language=en-US}}</ref>
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Borax is used in various household laundry and cleaning products,<ref name=HPD136/><ref name=USBor2022/> including the [[20 Mule Team Borax]] laundry booster, [[Boraxo]] powdered hand soap, and some [[tooth bleaching]] formulas.<ref name=hamm2004/><ref name=oneil2013/>
Borax is used in various household laundry and cleaning products,<ref name=HPD136/><ref name=USBor2022/> including the [[20 Mule Team Borax]] laundry booster, [[Boraxo]] powdered hand soap, and some [[tooth bleaching]] formulas.<ref name=hamm2004/><ref name=oneil2013/>


Borate ions (commonly supplied as boric acid) are used in biochemical and chemical laboratories to make [[buffer solution|buffers]], e.g. for [[polyacrylamide gel electrophoresis]] of DNA and RNA, such as [[TBE buffer]] (borate buffered tris-hydroxymethylaminomethonium)<ref name=peac1967/><ref name=ande1981/> or the newer SB buffer or [[BBS buffer]] (borate buffered saline) in coating procedures. Borate buffers (usually at pH 8) are also used as preferential equilibration solutions in [[dimethyl pimelimidate]] (DMP) based crosslinking reactions.<ref>{{cite book |last1=Harvey |first1=Dexter |last2=Rutledge |first2=Nicky |title=Industrial Chemistry |date=1 April 2019 |publisher=EdTech Press |location=Waltham Abbey |isbn=978-1-83947-197-1 |page=255 |url=https://www.google.co.uk/books/edition/Industrial_Chemistry/feLEDwAAQBAJ?hl=en&gbpv=1&dq=dimethyl+pimelimidate+borax&pg=PA255&printsec=frontcover |language=en}}</ref>
Borate ions (commonly supplied as boric acid) are used in biochemical and chemical laboratories to make [[buffer solution|buffers]], e.g. for [[polyacrylamide gel electrophoresis]] of DNA and RNA, such as [[TBE buffer]] (borate buffered tris-hydroxymethylaminomethonium)<ref name=peac1967/><ref name=ande1981/> or the newer SB buffer or [[BBS buffer]] (borate buffered saline) in coating procedures. Borate buffers (usually at pH 8) are also used as preferential equilibration solutions in [[dimethyl pimelimidate]] (DMP) based crosslinking reactions.<ref>{{cite book |last1=Harvey |first1=Dexter |last2=Rutledge |first2=Nicky |title=Industrial Chemistry |date=1 April 2019 |publisher=EdTech Press |location=Waltham Abbey |isbn=978-1-83947-197-1 |page=255 |url=https://books.google.com/books?id=feLEDwAAQBAJ&dq=dimethyl+pimelimidate+borax&pg=PA255 |language=en}}</ref>


Borax as a source of borate has been used to take advantage of the co-complexing ability of borate with other agents in water to form complex ions with various substances. Borate and a suitable [[polymer]] bed are used to [[chromatograph]] non-[[glycated]] [[hemoglobin]] differentially from [[glycated hemoglobin]] (chiefly [[HbA1c]]), which is an indicator of long-term [[hyperglycemia]] in [[diabetes mellitus]].
Borax as a source of borate has been used to take advantage of the co-complexing ability of borate with other agents in water to form complex ions with various substances. Borate and a suitable [[polymer]] bed are used to [[chromatograph]] non-glycated [[hemoglobin]] differentially from [[glycated hemoglobin]] (chiefly [[HbA1c]]), which is an indicator of long-term [[hyperglycemia]] in [[diabetes mellitus]]{{citation needed|date=July 2025}}


Borax alone does not have a high affinity for ''[[Hard water#Sources of hardness|hardness cations]]'', although it has been used for water-softening. Its chemical equation for ''[[water softening|water-softening]]'' is given below:
Borax alone does not have a high affinity for [[Hard water#Types|hardness cations]], although it has been used for water softening. A general chemical equation for [[water softening]] is (R is the dissolved cation, usually calcium or magnesium):


:{{chem2|[[calcium|Ca]](2+)(aq) + [[sodium|Na]]2[[boron|B]]4[[oxygen|O]]7(aq) → CaB4O7(s)↓ + 2 Na+(aq)}}
:{{chem2|R(2+)(aq) + Na2B4O7(aq) → RB4O7(s)↓ + 2 Na+(aq)}}
:{{chem2|[[magnesium|Mg]](2+)(aq) + Na2B4O7(aq) → MgB4O7(s)↓ + 2 Na+(aq)}}


The [[sodium]] ions introduced do not make water "hard". This method is suitable for removing both temporary and permanent types of hardness.
The sodium ions introduced do not make water "hard". This method is suitable for removing both temporary and permanent types of hardness.{{citation needed|date=July 2025}}


A mixture of borax and [[ammonium chloride]] is used as a [[Flux (metallurgy)|flux]] when [[welding]] [[iron]] and [[steel]]. It lowers the melting point of the unwanted [[iron oxide]] ([[Mill scale|scale]]), allowing it to run off. Borax is also mixed with water as a flux when [[soldering]] [[jewelry]] [[metal]]s such as [[gold]] or [[silver]], where it allows the molten [[solder]] to [[Wetting|wet]] the metal and flow evenly into the joint.<ref>{{cite book |last1=Hasluck |first1=Paul Nooncree |author1-link=Paul N. Hasluck |title=The Mechanic's Workshop Handybook |date=1895 |publisher=Crosby Lockwood |location=London |page=62 |url=https://www.google.co.uk/books/edition/The_Mechanic_s_Workshop_Handybook/R1xRAAAAYAAJ?hl=en&gbpv=1&dq=borax+gold+jewellery&pg=PA62&printsec=frontcover}}</ref> Borax is also a good flux for "pre-tinning" [[tungsten]] with [[zinc]], making the tungsten soft-solderable.<ref name=dodd1966/> Borax is often used as a flux for [[forge welding]].<ref name="Moehring-2016" />
A mixture of borax and [[ammonium chloride]] is used as a [[Flux (metallurgy)|flux]] when [[welding]] [[iron]] and [[steel]]. It lowers the melting point of the unwanted [[iron oxide]] ([[Mill scale|scale]]), allowing it to run off. Borax is also mixed with water as a flux when [[soldering]] [[jewelry]] [[metal]]s such as [[gold]] or [[silver]], where it allows the molten [[solder]] to [[Wetting|wet]] the metal and flow evenly into the joint.<ref>{{cite book |last1=Hasluck |first1=Paul Nooncree |author1-link=Paul N. Hasluck |title=The Mechanic's Workshop Handybook |date=1895 |publisher=Crosby Lockwood |location=London |page=62 |url=https://books.google.com/books?id=R1xRAAAAYAAJ&dq=borax+gold+jewellery&pg=PA62}}</ref> Borax is also a flux for "pre-tinning" [[tungsten]] with [[zinc]], making the tungsten soft-solderable.<ref name=dodd1966/> Borax is often used as a flux for [[forge welding]].<ref name="Moehring-2016" />


[[File:Borax wagons.jpg|thumb|Old [[steam tractor]] with borax wagons, [[Death Valley National Park]] ]]
[[File:Borax wagons.jpg|thumb|Old [[steam tractor]] with borax wagons, [[Death Valley National Park]] ]]


In [[Artisanal mining|artisanal gold mining]], borax is sometimes used as part of a process known as the [[borax method]] (as a flux) meant to eliminate the need for toxic mercury in the [[gold extraction]] process, although it cannot directly replace mercury. Borax was reportedly used by gold miners in parts of the [[Philippines]] in the 1900s.<ref name=BSmith2012/><ref name=GEUS2008/> There is evidence that, in addition to reducing the environmental impact, this method achieves better gold recovery for suitable ores and is less expensive. This borax method is used in northern [[Luzon]] in the Philippines, but miners have been reluctant to adopt it elsewhere for reasons that are not well understood.<ref name=appel2012/> The method has also been promoted in Bolivia<ref name=ande2015/> and Tanzania.<ref name=appel1969/>
In [[Artisanal mining|artisanal gold mining]], borax is sometimes used as part of a process known as the [[borax method]] (as a flux) meant to eliminate the need for toxic mercury in the [[gold extraction]] process, although it cannot directly replace mercury. Borax was reportedly used by gold miners in parts of the Philippines in the 1900s.<ref name=BSmith2012/><ref name=GEUS2008/> There is evidence that, in addition to reducing the environmental impact, this method achieves better gold recovery for suitable ores and is less expensive. This borax method is used in northern [[Luzon]] in the Philippines, but miners have been reluctant to adopt it elsewhere for reasons that are not well understood.<ref name=appel2012/> The method has also been promoted in Bolivia<ref name=ande2015/> and Tanzania.<ref name=appel1969/>


A rubbery polymer sometimes called [[Slime (toy)|Slime]], [[Flubber (material)|Flubber]], 'gluep' or 'glurch' (or erroneously called [[Silly Putty]], which is based on silicone polymers), can be made by [[cross-link]]ing [[polyvinyl alcohol]] with borax. Making flubber from [[polyvinyl acetate]]-based [[glue]]s, such as [[Elmer's Products, Inc.|Elmer's Glue]], and borax is a common elementary science demonstration.<ref name=parr1998/><ref name=ChemAboutXXXX/>
A rubbery polymer sometimes called [[Slime (toy)|Slime]], [[Flubber (material)|Flubber]], "gluep" or "glurch" (or erroneously called [[Silly Putty]], which is based on silicone polymers), can be made by [[cross-link]]ing [[polyvinyl alcohol]] with borax.<ref>{{cite web |title=How to Make Homemade Slime {{!}} Crafts for Kids |url=https://www.pbs.org/parents/crafts-and-experiments/homemade-gak |website=PBS KIDS for Parents |publisher=[[PBS]] |access-date=8 July 2025 |language=en}}</ref> Making flubber from [[polyvinyl acetate]]-based glues, such as Elmer's Glue, and borax is a common elementary science demonstration.<ref name=parr1998/><ref name=ChemAboutXXXX/>


Borax, given the [[E number]] ''E285'', is used as a [[food additive]] but this use is banned in some countries, such as [[Australia]], [[China]], [[Thailand]] and the [[United States]].<ref name=reil2019/> As a consequence, certain foods, such as [[caviar]], produced for sale in the United States contain higher levels of [[salt]] to assist preservation.<ref name=HansonLtd2008/> In addition to its use as a preservative, borax imparts a firm, rubbery texture to food. In [[China]], borax ({{lang-zh|c=硼砂|p=péng shā}} or {{lang-zh|c=月石|p=yuè shí}}) has been found in foods including wheat and rice noodles named ''[[lamian]]'' ({{lang-zh|s=拉面|p=lāmiàn}}), ''[[shahe fen]]'' ({{lang-zh|s=沙河粉|p=shāhéfěn}}), ''[[char kway teow]]'' ({{lang-zh|c=粿條|p=guǒ tiáo}}), and ''[[chee cheong fun]]'' ({{lang-zh|s=肠粉|p=chángfěn}}){{clarify|Most of these are dishes, not wheat and rice noodles, and at least one is just a dish made from another listed noodle.|date=March 2023}}<ref name="Chow2005" /> In [[Indonesia]], it is a common, but forbidden,<ref name="PomGo2021" /> additive to such foods as noodles, [[bakso]] (meatballs), and steamed rice.
Borax, given the [[E number]] ''E285'', is used as a [[food additive]] but this use is banned in some countries, such as Australia, China, Thailand and the United States.<ref name=reil2019/> As a consequence, certain foods, such as [[caviar]], produced for sale in the United States contain higher levels of salt to assist preservation.<ref name=HansonLtd2008/> In addition to its use as a preservative, borax imparts a firm, rubbery texture to food. In China, borax ({{lang-zh|c=硼砂|p=péng shā}} or {{lang-zh|c=月石|p=yuè shí|link=no}}) has been found in foods including wheat and rice noodles named ''[[lamian]]'' ({{lang-zh|s=拉面|p=lāmiàn|link=no}}), ''[[shahe fen]]'' ({{lang-zh|s=沙河粉|p=shāhéfěn|link=no}}), ''[[char kway teow]]'' ({{lang-zh|c=粿條|p=guǒ tiáo|link=no}}), and ''[[chee cheong fun]]'' ({{lang-zh|s=肠粉|p=chángfěn|link=no}}){{clarify|Most of these are dishes, not wheat and rice noodles, and at least one is just a dish made from another listed noodle.|date=March 2023}}<ref name="Chow2005" /> In Indonesia, it is a common, but forbidden,<ref name="PomGo2021" /> additive to such foods as noodles, [[bakso]] (meatballs), and steamed rice.


[[File:Boron mine pit.jpg|thumbnail|Rio Tinto borax mine pit, [[Boron, California]]]]
[[File:Boron mine pit.jpg|thumbnail|Rio Tinto borax mine pit, [[Boron, California]]]]


=== Other ===
Other uses include:
Other uses include:


* Ingredient in [[vitreous enamel|enamel]] glazes<ref name=Sheff2019/>
* Ingredient in [[vitreous enamel|enamel glazes]].<ref name=Sheff2019/>
* Component of [[glass]], [[pottery]], and [[ceramic]]s<ref name="Schubert-2003"/>
* Component of [[glass]], [[pottery]], and [[ceramic]]s.<ref name="Schubert-2003"/>
* Used as an additive in ceramic slips and [[ceramic glaze|glazes]] to improve fit on wet, greenware, and [[bisque (pottery)|bisque]]{{citation needed|date=September 2019}}
* Used as an additive in ceramic slips and [[ceramic glaze]]s to improve fit on wet, greenware, and [[bisque (pottery)|bisque]].{{citation needed|date=September 2019}}
* [[Fire retardant]]<ref name=shen1998/><ref>{{cite web | url=https://www.arkansasairandmilitary.com/post/artifact-friday-k2b-flight-suit | title=Artifact Friday: K2B Flight Suit | date=August 11, 2023 }}</ref><ref>{{cite web | url=http://www.vietnamgear.com/kit.aspx?kit=61 | title=K-2B Flying Coveralls }}</ref>
* [[Flame retardant]] treatment for fabric.<ref name=shen1998/><ref>{{cite web | url=https://www.arkansasairandmilitary.com/post/artifact-friday-k2b-flight-suit | title=Artifact Friday: K2B Flight Suit | date=August 11, 2023 }}</ref><ref>{{cite web | url=http://www.vietnamgear.com/kit.aspx?kit=61 | title=K-2B Flying Coveralls }}</ref>
* [[Fungicide|Anti-fungal]] compound for [[cellulose insulation]]<ref name="Schubert-2003" />
* [[Fungicide|Anti-fungal]] compound for [[cellulose insulation]].<ref name="Schubert-2003" />
* Mothproofing 10% solution for wool<ref name=CAltTech2016/>
* Mothproofing 10% solution for wool.<ref name=CAltTech2016/>
* Pulverized for the prevention of stubborn pests (e.g. [[German cockroach]]es) in closets, pipe and cable inlets, wall [[panelling]] gaps, and inaccessible locations where ordinary [[pesticide]]s are undesirable<ref name=murr1989/>
* Pulverized for the prevention of stubborn pests (e.g. [[German cockroach]]es) in closets, pipe and cable inlets, wall panelling gaps, and inaccessible locations where ordinary [[pesticide]]s are undesirable.<ref>{{cite book |last1=Rierson |first1=Donald A. |title=Understanding and controlling the German cockroach |date=1995 |publisher=Oxford University Press |isbn=9780195345087 |page=232|url=https://books.google.com/books?id=4j8n8hIBEa0C&dq=cockroach+borax&pg=PA232}}</ref>
* Precursor for [[sodium perborate|sodium perborate monohydrate]] that is used in [[detergent]]s, as well as for [[boric acid]] and other [[borate]]s{{citation needed|date=September 2019}}
* [[Tackifier]] ingredient in [[casein]], [[starch]] and [[dextrin]]-based adhesives.<ref name=suar2011/>
* [[Tackifier]] ingredient in [[casein]], [[starch]] and [[dextrin]]-based adhesives<ref name=suar2011/>
* To make indelible ink for [[dip pen]]s by dissolving [[shellac]] into heated borax.{{citation needed|date=September 2019}}
* Precursor for [[boric acid]], a tackifier ingredient in [[polyvinyl acetate]], [[polyvinyl alcohol]]-based adhesives
* [[Curing agent]] for [[snake]] skins.{{citation needed|date=September 2019}}
* To make indelible ink for [[dip pen]]s by dissolving [[shellac]] into heated borax{{citation needed|date=September 2019}}
* Curing agent for [[salmon]] eggs, for use in sport fishing for salmon.<ref name=rams2021/>
* [[Curing agent]] for [[snake]] skins{{citation needed|date=September 2019}}
* Swimming pool [[buffering agent]] to control [[pH]].<ref name=Pools2008/>
* Curing agent for [[salmon]] eggs, for use in sport fishing for salmon<ref name=rams2021/>
* In [[boiling water reactor|nuclear reactor]]s and spent fuel pools as a [[neutron absorber]] to control reactivity and to shut down a nuclear chain reaction.<ref name=BARC2010/>
* Swimming pool [[buffering agent]] to control [[pH]]<ref name=Pools2008/>
* As a [[micronutrient]] fertilizer to correct [[Boron deficiency (plant disorder)|boron-deficient soils]].<ref name=NatBer2016/><ref name=SpeAnal2016/>
* [[Neutron absorber]], are used in [[boiling water reactor|nuclear reactor]]s and spent fuel pools to control reactivity and to shut down a nuclear chain reaction<ref name=BARC2010/>
* [[Preservative]] in [[taxidermy]].<ref name=Taxid2021/>
* As a [[micronutrient]] [[fertilizer]] to correct [[Boron deficiency (plant disorder)|boron-deficient soils]]<ref name=NatBer2016/><ref name=SpeAnal2016/>
* To color fires with a green tint.<ref name=marie2016/>
* [[Preservative]] in [[taxidermy]]<ref name=Taxid2021/>
* Traditionally used to coat dry-cured meats such as hams to improve the appearance and discourage flies.<ref name=nich1991/><ref name=NHSBH1906/><ref name=IndonesiaDCP/>
* To color fires with a green tint<ref name=marie2016/>
* Used as a flux for melting metals and alloys in [[Casting (metalworking)|casting]] to draw out impurities and prevent [[Redox|oxidation]].{{citation needed|date=September 2019}}
* Traditionally used to coat dry-cured meats such as hams to improve the appearance and discourage flies<ref name=nich1991/><ref name=NHSBH1906/><ref name=IndonesiaDCP/>
* Used as a [[woodworm]] treatment (diluted in water).{{citation needed|date=September 2019}}
* Used by [[blacksmith]]s in [[forge welding]]<ref name="Moehring-2016"/>
* Used as a [[Flux (metallurgy)|flux]] for melting metals and alloys in [[Casting (metalworking)|casting]] to draw out impurities and prevent [[Redox|oxidation]]{{citation needed|date=September 2019}}
* Used as a [[woodworm]] treatment (diluted in water){{citation needed|date=September 2019}}
* In [[particle physics]] as an additive to [[nuclear emulsion]], to extend the latent image lifetime of charged particle tracks. The first observation of the [[pion]], which was awarded the 1950 [[Nobel Prize]], used this type of emulsion.<ref name=latt1947/><ref name=latt1947b/>
* In [[particle physics]] as an additive to [[nuclear emulsion]], to extend the latent image lifetime of charged particle tracks. The first observation of the [[pion]], which was awarded the 1950 [[Nobel Prize]], used this type of emulsion.<ref name=latt1947/><ref name=latt1947b/>


== Toxicity ==
== Toxicity ==
According to one study, borax is not acutely toxic. Its {{LD50}} (median lethal dose) score is tested at 2.66 g/kg in rats, meaning that a significant dose of the chemical is needed to cause severe symptoms or death.
According to one study, borax is not acutely toxic. Its {{LD50}} (median lethal dose) score is tested at 2.66 g/kg in rats, meaning that a significant dose of the chemical is needed to cause severe symptoms or death.{{citation needed|date=July 2025}}


The lethal dose is not necessarily the same for humans; human studies in three borate exposure-rich comparison groups (U.S. Borax mine and production facility workers, Chinese boron workers, Turkish residents living near boron rich regions) produced no indicators of developmental toxicity in blood and semen tests. The highest estimated exposure was 5&nbsp;mg B/kg/day, likely due to eating in contaminated workplaces, more than 100 times the average daily exposure.<ref name="CLH2018">{{cite web |title= CLH report for boric acid – Proposal for Harmonised Classification and Labelling |publisher= Bureau for Chemical Substances |url= https://echa.europa.eu/documents/10162/23665416/clh_rep_boric_acid_5521_en.pdf/ee39f026-9d2d-28f7-5d90-63a424112162 |date= 23 April 2018 |access-date= 18 October 2018 |place= Lodz, Poland }}</ref>
The lethal dose is not necessarily the same for humans; human studies in three borate exposure-rich comparison groups (U.S. Borax mine and production facility workers, Chinese boron workers, Turkish residents living near boron rich regions) produced no indicators of developmental toxicity in blood and semen tests. The highest estimated exposure was 5&nbsp;mg B/kg/day, likely due to eating in contaminated workplaces, more than 100 times the average daily exposure.<ref name="CLH2018">{{cite web |title= CLH report for boric acid – Proposal for Harmonised Classification and Labelling |publisher= Bureau for Chemical Substances |url= https://echa.europa.eu/documents/10162/23665416/clh_rep_boric_acid_5521_en.pdf/ee39f026-9d2d-28f7-5d90-63a424112162 |date= 23 April 2018 |access-date= 18 October 2018 |place= Lodz, Poland }}</ref>


Borax is absorbed poorly through intact skin, although fatalities have been recorded in persistent treatment of rashes and open wounds with boric acid-containing ointments and bath solutions. Borax is readily absorbed orally, well above 90%, and mostly excreted through the urine. Fatal cases attributed to ingestion include small children mistakenly drinking pesticides or suicide attempts with large volumes of crystals. No genotoxicity or carcinogenicity has been recorded in studies.<ref>{{cite journal  | title = Toxicity of boric acid, borax and other boron containing compounds: A review| journal = Regul Toxicol Pharmacol |date=2021 | url = https://pubmed.ncbi.nlm.nih.gov/33485927/ | doi = 10.1016/j.yrtph.2021.104873| pmid = 33485927  | last1 = Hadrup | first1 = Niels | last2 = Frederiksen | first2 = Marie | last3 = Sharma | first3 = Anoop K. | volume = 121 }}</ref>
Borax is absorbed poorly through intact skin, although fatalities have been recorded in persistent treatment of rashes and open wounds with boric acid-containing ointments and bath solutions. Borax is readily absorbed orally, well above 90%, and mostly excreted through the urine. Fatal cases attributed to ingestion include small children mistakenly drinking pesticides or suicide attempts with large volumes of crystals. No genotoxicity or carcinogenicity has been recorded in studies.<ref>{{cite journal  | title = Toxicity of boric acid, borax and other boron containing compounds: A review| journal = Regul Toxicol Pharmacol |date=2021 | doi = 10.1016/j.yrtph.2021.104873| pmid = 33485927  | last1 = Hadrup | first1 = Niels | last2 = Frederiksen | first2 = Marie | last3 = Sharma | first3 = Anoop K. | volume = 121 | article-number = 104873 }}</ref>


Borax has been in use as an insecticide in the United States with various restrictions since 1946. All restrictions were removed in February 1986 due to the low toxicity of borax, as reported in two EPA documents relating to boric acid and borax.<ref name=EPA.Pest/><ref name=EPA.BoraxOK/>
Borax has been in use as an insecticide in the United States with various restrictions since 1946. All restrictions were removed in February 1986 due to the low toxicity of borax, as reported in two EPA documents relating to boric acid and borax.<ref name=EPA.Pest/><ref name=EPA.BoraxOK/>
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Overexposure to borax dust can cause respiratory irritation, while no skin irritation is known to exist due to external borax exposure. Ingestion may cause gastrointestinal distress including [[nausea]], persistent vomiting, abdominal pain, and [[diarrhea]]. Effects on the vascular system and [[human brain]] include headaches and lethargy but are less frequent. In severe cases, a "beefy" red rash affecting the palms, soles, buttocks and scrotum has occurred.<ref name=reig2009/>
Overexposure to borax dust can cause respiratory irritation, while no skin irritation is known to exist due to external borax exposure. Ingestion may cause gastrointestinal distress including [[nausea]], persistent vomiting, abdominal pain, and [[diarrhea]]. Effects on the vascular system and [[human brain]] include headaches and lethargy but are less frequent. In severe cases, a "beefy" red rash affecting the palms, soles, buttocks and scrotum has occurred.<ref name=reig2009/>
The Indonesian Directorate of Consumer Protection warns of the risk of [[liver cancer]] with high consumption of borax over a period of 5–10 years.<ref name=IndonesiaDCP/>


Borax was added to the [[Substance of very high concern|Substance of Very High Concern (SVHC)]] candidate list on December 16, 2010. The SVHC candidate list is part of the [[European Union|EU]] Regulations on the [[Registration, Evaluation, Authorisation and Restriction of Chemicals]] 2006 (REACH), and the addition was based on the revised classification of borax as ''toxic for reproduction'' category 1B under the [[CLP Regulation]]s. Substances and mixtures imported into the EU which contain borax are now required to be labelled with the warnings "May damage fertility" and "May damage the unborn child".<ref name=ECHA2010/> It was proposed for addition to REACH Annex XIV by the [[European Chemicals Agency|ECHA]] on July 1, 2015.<ref name=ECHA2015/> If this recommendation is approved, all imports and uses of borax in the EU will have to be authorized by the ECHA.{{update after|2016|8|17}}
Borax was added to the [[Substance of very high concern|Substance of Very High Concern (SVHC)]] candidate list on December 16, 2010. The SVHC candidate list is part of the [[European Union|EU]] Regulations on the [[Registration, Evaluation, Authorisation and Restriction of Chemicals]] 2006 (REACH), and the addition was based on the revised classification of borax as ''toxic for reproduction'' category 1B under the [[CLP Regulation]]s. Substances and mixtures imported into the EU which contain borax are now required to be labelled with the warnings "May damage fertility" and "May damage the unborn child".<ref name=ECHA2010/> It was proposed for addition to REACH Annex XIV by the [[European Chemicals Agency|ECHA]] on July 1, 2015.<ref name=ECHA2015/> If this recommendation is approved, all imports and uses of borax in the EU will have to be authorized by the ECHA.{{update after|2016|8|17}}
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== References ==
== References ==
{{reflist|refs=
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<ref name="haynes2011">{{Cite book |title=CRC Handbook of Chemistry and Physics |title-link=CRC Handbook of Chemistry and Physics |publisher=[[CRC Press]] |year=2011 |isbn=978-1439855119 |editor-last=Haynes, William M. |edition=92nd}}</ref>
<ref name="levy1978">{{Cite journal |last1=Levy |first1=H. A. |last2=Lisensky |first2=G. C. |year=1978 |title=Crystal structures of sodium sulfate decahydrate (Glauber's salt) and sodium tetraborate decahydrate (borax). Redetermination by neutron diffraction |journal=Acta Crystallographica Section B |volume=34 |issue=12 |pages=3502–3510 |bibcode=1978AcCrB..34.3502L |doi=10.1107/S0567740878011504}}</ref>
<ref name="levy1978">{{Cite journal |last1=Levy |first1=H. A. |last2=Lisensky |first2=G. C. |year=1978 |title=Crystal structures of sodium sulfate decahydrate (Glauber's salt) and sodium tetraborate decahydrate (borax). Redetermination by neutron diffraction |journal=Acta Crystallographica Section B |volume=34 |issue=12 |pages=3502–3510 |bibcode=1978AcCrB..34.3502L |doi=10.1107/S0567740878011504}}</ref>
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<ref name="PGCH59">{{PGCH|0059}}</ref>
<ref name="PGCH59">{{PGCH|0059}}</ref>
<ref name="PGCH58">{{PGCH|0058}}</ref>
<ref name="PGCH58">{{PGCH|0058}}</ref>
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<ref name="mari1962">{{Cite journal |last1=Maričić |first1=S. |last2=Pravdić |first2=V. |last3=Veksli |first3=Z. |date=November 1962 |title=Proton conductivity in borax, Na2[B4O5(OH)4]-8H2O |url=https://linkinghub.elsevier.com/retrieve/pii/0022369762902482 |journal=Journal of Physics and Chemistry of Solids |language=en |volume=23 |issue=11 |pages=1651–1659 |doi=10.1016/0022-3697(62)90248-2|bibcode=1962JPCS...23.1651M |url-access=}}</ref>
<ref name="SciAm1877">{{Cite magazine |date=September 22, 1877 |title=American Borax Production |magazine=[[Scientific American]] |pages=184–185 |volume=37 |jstor=26062263 |number=12}}. The article states that the distance between [[Columbus, Nevada]] and [[Wadsworth, Nevada]] is "about 360 miles" whereas today the distance on modern roads is about 160 miles.</ref>
<ref name="SciAm1877">{{Cite magazine |date=September 22, 1877 |title=American Borax Production |magazine=[[Scientific American]] |pages=184–185 |volume=37 |jstor=26062263 |number=12}}. The article states that the distance between [[Columbus, Nevada]] and [[Wadsworth, Nevada]] is "about 360 miles" whereas today the distance on modern roads is about 160 miles.</ref>
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<ref name="ChemIn1976">Chemical Age of India, Vol. 37, No.10 & 11 (1976){{full citation needed|date=August 2024}}</ref>
<ref name="ChemIn1976">Chemical Age of India, Vol. 37, No.10 & 11 (1976){{full citation needed|date=August 2024}}</ref>
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<ref name="murr1989">{{Cite web |last=Murray |first=Lynda M. |date=1989 |title=Least toxic pest control: how infestations of termites, ants, fleas, ticks, and beetles can be controlled without causing short- or long-term indoor air quality changes and health risks |url=https://nepis.epa.gov/Exe/ZyPDF.cgi/9100YHGT.PDF?Dockey=9100YHGT.PDF |url-status=dead |archive-url=https://web.archive.org/web/20220626035430/https://nepis.epa.gov/Exe/ZyPDF.cgi/9100YHGT.PDF?Dockey=9100YHGT.PDF |archive-date=June 26, 2022 |access-date=2022-06-25 |website=nepis.epa.gov |publisher=United States Environmental Protection Agency |language=en}}</ref>
<ref name="suar2011">{{Citation |last=Suárez |first=Juan C. |title=Handbook of Adhesion Technology |date=2011 |pages=1385–1408 |editor-last=da Silva |editor-first=Lucas F. M. |editor-last2=Öchsner |editor-first2=Andreas |editor-last3=Adams |editor-first3=Robert D. |chapter=Bioadhesives |publisher=Springer Berlin Heidelberg |language=en |doi=10.1007/978-3-642-01169-6_53 |isbn=978-3-642-01168-9}}</ref>
<ref name="suar2011">{{Citation |last=Suárez |first=Juan C. |title=Handbook of Adhesion Technology |date=2011 |pages=1385–1408 |editor-last=da Silva |editor-first=Lucas F. M. |editor-last2=Öchsner |editor-first2=Andreas |editor-last3=Adams |editor-first3=Robert D. |chapter=Bioadhesives |publisher=Springer Berlin Heidelberg |language=en |doi=10.1007/978-3-642-01169-6_53 |isbn=978-3-642-01168-9}}</ref>
<ref name="rams2021">{{Cite web |title=Curing eggs for steelhead, steelhead egg cures, Buzz Ramsey, Bill Swann, Andy Martin |url=https://wildriversfishing.com/article6.html |access-date=2021-04-16 |website=wildriversfishing.com}}</ref>
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<ref name="NHSBH1906">{{Cite web |year=1906 |title=Report of the State Board of Health of the State of New Hampshire ..., Volume 19 |url=https://books.google.com/books?id=6M9KAQAAMAAJ&q=borax+ham&pg=PA171 |pages=169–171}}</ref>
<ref name="NHSBH1906">{{Cite web |year=1906 |title=Report of the State Board of Health of the State of New Hampshire ..., Volume 19 |url=https://books.google.com/books?id=6M9KAQAAMAAJ&q=borax+ham&pg=PA171 |pages=169–171}}</ref>
<ref name="Moehring-2016">{{Cite journal |last1=Moehring |first1=Jack |last2=Willman |first2=Michael |last3=Pulscher |first3=Isaac |last4=Rowe |first4=Devin |date=Dec 2016 |title=Bladesmithing at South Dakota School of Mines and Technology |journal=JOM |language=en |volume=68 |issue=12 |pages=3186–3192 |bibcode=2016JOM....68l3186M |doi=10.1007/s11837-016-2139-z |issn=1047-4838 |s2cid=137747858}}</ref>
<ref name="Moehring-2016">{{Cite journal |last1=Moehring |first1=Jack |last2=Willman |first2=Michael |last3=Pulscher |first3=Isaac |last4=Rowe |first4=Devin |date=Dec 2016 |title=Bladesmithing at South Dakota School of Mines and Technology |journal=JOM |language=en |volume=68 |issue=12 |pages=3186–3192 |bibcode=2016JOM....68l3186M |doi=10.1007/s11837-016-2139-z |issn=1047-4838 |s2cid=137747858}}</ref>
<ref name="latt1947">{{Cite journal |last1=Lattes |first1=C.M.G. |last2=Fowler |first2=R.H. |last3=Cuer |first3=R. |year=1947 |title=Range-Energy Relation for Protons and a-Particles in the New Ilford 'Nuclear Research' Emulsions |journal=Nature |volume=159 |pages=301–302|doi=10.1038/159301a0 }}</ref>
<ref name="latt1947">{{Cite journal |last1=Lattes |first1=C.M.G. |last2=Fowler |first2=R.H. |last3=Cuer |first3=R. |year=1947 |title=Range-Energy Relation for Protons and a-Particles in the New Ilford 'Nuclear Research' Emulsions |journal=Nature |volume=159 |pages=301–302|doi=10.1038/159301a0}}</ref>
<ref name="latt1947b">{{Cite journal |last1=Lattes |first1=C.M.G. |last2=Occhialini |first2=G.P.S. |year=1947 |title=Determination of the Energy and Momentum of Fast Neutrons in Cosmic Rays |journal=Nature |volume=159 |issue=4036 |pages=331–332|doi=10.1038/159331a0 |pmid=20293532 |bibcode=1947Natur.159..331L }}</ref>
<ref name="latt1947b">{{Cite journal |last1=Lattes |first1=C.M.G. |last2=Occhialini |first2=G.P.S. |year=1947 |title=Determination of the Energy and Momentum of Fast Neutrons in Cosmic Rays |journal=Nature |volume=159 |issue=4036 |pages=331–332|doi=10.1038/159331a0 |pmid=20293532 |bibcode=1947Natur.159..331L}}</ref>
<ref name="EPA.Pest">{{Cite web |title=Pesticide Reregistration Status |url=https://archive.epa.gov/pesticides/reregistration/web/pdf/0024fact.pdf |access-date=August 7, 2016 |website=Epa.gov}}</ref>
<ref name="EPA.Pest">{{Cite web |title=Pesticide Reregistration Status |url=https://archive.epa.gov/pesticides/reregistration/web/pdf/0024fact.pdf |access-date=August 7, 2016 |website=Epa.gov}}</ref>
<ref name="EPA.BoraxOK">{{Cite web |date=August 20, 2015 |title=Pesticides |url=http://www3.epa.gov/pesticides/chem_search/cleared_reviews/csr_PC-011103_25-Apr-93_002.pdf |access-date=August 7, 2016 |website=Epa.gov}}</ref>
<ref name="EPA.BoraxOK">{{Cite web |date=August 20, 2015 |title=Pesticides |url=https://www3.epa.gov/pesticides/chem_search/cleared_reviews/csr_PC-011103_25-Apr-93_002.pdf |access-date=August 7, 2016 |website=Epa.gov}}</ref>
<ref name="EPA.Reg62.4">{{Cite web |title=Regulations.gov |url=http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2005-0062-0004 |url-status=dead |archive-url=https://web.archive.org/web/20150503044719/http://www.regulations.gov/ |archive-date=May 3, 2015 |access-date=April 27, 2015}}</ref>
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<ref name="ECHA2010">[https://web.archive.org/web/20110725113454/http://echa.europa.eu/doc/candidate_list/svhc_supdoc_disodium_tetraborate_anhydrous_publication.pdf Member state committee draft support document for identification of disodium tetraborate, anhydrous as a substance of very high concern because of its CMR properties]. Adopted on June 9, 2010. Echa.europa.eu. Retrieved on February 17, 2012.</ref>
<ref name="ECHA2010">[https://web.archive.org/web/20110725113454/http://echa.europa.eu/doc/candidate_list/svhc_supdoc_disodium_tetraborate_anhydrous_publication.pdf Member state committee draft support document for identification of disodium tetraborate, anhydrous as a substance of very high concern because of its CMR properties]. Adopted on June 9, 2010. Echa.europa.eu. Retrieved on February 17, 2012.</ref>
<ref name="ECHA2015">[http://echa.europa.eu/documents/10162/13640/6th_a_xiv_recommendation_01july2015_en.pdf Recommendation of the European Chemicals Agency of 1 July 2015 for the inclusion of substances in Annex XIV to REACH (List of Substances subject to Authorisation)] {{Webarchive|url=https://web.archive.org/web/20150714163309/http://echa.europa.eu/documents/10162/13640/6th_a_xiv_recommendation_01july2015_en.pdf |date=July 14, 2015 }} Echa.europa.eu. Retrieved on July 6, 2015.</ref>
<ref name="ECHA2015">[http://echa.europa.eu/documents/10162/13640/6th_a_xiv_recommendation_01july2015_en.pdf Recommendation of the European Chemicals Agency of 1 July 2015 for the inclusion of substances in Annex XIV to REACH (List of Substances subject to Authorisation)] {{Webarchive|url=https://web.archive.org/web/20150714163309/http://echa.europa.eu/documents/10162/13640/6th_a_xiv_recommendation_01july2015_en.pdf |date=July 14, 2015}} Echa.europa.eu. Retrieved on July 6, 2015.</ref>
<ref name="bolt2012">{{Cite journal |last1=Bolt |first1=Hermann M. |last2=Başaran |first2=Nurşen |last3=Duydu |first3=Yalçın |year=2012 |title=Human Environmental and Occupational Exposures to Boric Acid: Reconciliation with Experimental Reproductive Toxicity Data |journal=Journal of Toxicology and Environmental Health, Part A |volume=75 |issue=8–10 |pages=508–514 |bibcode=2012JTEHA..75..508B |doi=10.1080/15287394.2012.675301 |pmid=22686310 |s2cid=31972554}}</ref>
<ref name="bolt2012">{{Cite journal |last1=Bolt |first1=Hermann M. |last2=Başaran |first2=Nurşen |last3=Duydu |first3=Yalçın |year=2012 |title=Human Environmental and Occupational Exposures to Boric Acid: Reconciliation with Experimental Reproductive Toxicity Data |journal=Journal of Toxicology and Environmental Health, Part A |volume=75 |issue=8–10 |pages=508–514 |bibcode=2012JTEHA..75..508B |doi=10.1080/15287394.2012.675301 |pmid=22686310 |s2cid=31972554}}</ref>
<ref name="CanHealth2016">{{Cite web |date=July 22, 2016 |title=Information Update&nbsp;– Health Canada advises Canadians to avoid homemade craft and pesticide recipes using boric acid&nbsp;– Recalls & alerts |url=http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2016/59514a-eng.php |access-date=August 7, 2016 |website=Healthycanadians.gc.ca}}</ref>
<ref name="CanHealth2016">{{Cite web |date=July 22, 2016 |title=Information Update&nbsp;– Health Canada advises Canadians to avoid homemade craft and pesticide recipes using boric acid&nbsp;– Recalls & alerts |url=http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2016/59514a-eng.php |access-date=August 7, 2016 |website=Healthycanadians.gc.ca}}</ref>
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<ref name="akgu2021">{{Cite journal |last1=Akgül |first1=Mehmet |last2=Çamlıbel |first2=Osman |date=March 2021 |title=The use of borax pentahydrate of inorganic filler in medium density fiberboard production |url=http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-221X2021000100422&lng=es&nrm=iso&tlng=es |journal=Maderas. Ciencia y tecnología |language=en |volume=23 |doi=10.4067/S0718-221X2021000100422 |issn=0718-221X}}</ref>
<ref name="akgu2021">{{Cite journal |last1=Akgül |first1=Mehmet |last2=Çamlıbel |first2=Osman |date=March 2021 |title=The use of borax pentahydrate of inorganic filler in medium density fiberboard production |url=http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-221X2021000100422&lng=es&nrm=iso&tlng=es |journal=Maderas. Ciencia y tecnología |language=en |volume=23 |doi=10.4067/S0718-221X2021000100422 |issn=0718-221X}}</ref>
<ref name="sahin2002">{{Cite journal |last1=Şahin |first1=Ömer |last2=Bulutcu |first2=A. Nusret |year=2002 |title=Dehydration Behaviour of Borax Pentahydrate to Anhydrous Borax by Multi-Stage Heating in a Fluidized |url=https://journals.tubitak.gov.tr/chem/vol26/iss1/10 |journal=Turkish Journal of Chemistry |volume=26 |pages=89–96 |article-number=10}}</ref>
<ref name="sahin2002">{{Cite journal |last1=Şahin |first1=Ömer |last2=Bulutcu |first2=A. Nusret |year=2002 |title=Dehydration Behaviour of Borax Pentahydrate to Anhydrous Borax by Multi-Stage Heating in a Fluidized |url=https://journals.tubitak.gov.tr/chem/vol26/iss1/10 |journal=Turkish Journal of Chemistry |volume=26 |pages=89–96 |article-number=10}}</ref>
}}
</references>


== External links ==
== External links ==

Latest revision as of 13:42, 18 November 2025

Template:Short description Script error: No such module "other uses". Script error: No such module "Distinguish". Template:Use mdy dates Template:Chembox

Borax (also referred to as sodium borate, tincal (Template:IPAc-en) and tincar (Template:IPAc-en)) is a salt (ionic compound) normally encountered as a hydrated borate of sodium, with the chemical formula Template:Chem2.[1]Template:Efn Borax mineral is a crystalline borate mineral that occurs in only a few places worldwide in quantities that enable it to be mined economically.

Borax can be dehydrated by heating into other forms with less water of hydration. The anhydrous form of borax can also be obtained from the decahydrate or other hydrates by heating and then grinding the resulting glasslike solid into a powder. It is a white crystalline solid that dissolves in water to make a basic solution due to the tetraborate anion.

Borax is commonly available in powder or granular form and has many industrial and household uses, including as a pesticide, as a metal soldering flux, as a component of glass, enamel, and pottery glazes, for tanning of skins and hides, for artificial aging of wood, as a preservative against wood fungus, as a food additive, and as a pharmaceutic alkalizer. In chemical laboratories it is used as a buffering agent.[1][2]

The terms tincal and tincar refer to the naturally occurring borax historically mined from dry lake beds in various parts of Asia.[3]

History

Borax was first discovered in dry lake beds in Tibet. Native tincal from Tibet, Persia, and other parts of Asia was traded via the Silk Road to the Arabian Peninsula in the 8th century AD.[3]

Borax first came into common use in the late 19th century when Francis Marion Smith's Pacific Coast Borax Company began to market and popularize a large variety of applications under the 20 Mule Team Borax trademark, named for the method by which borax was originally hauled out of the California and Nevada deserts.[4][5]

Etymology

The English word borax and its previous Middle form Script error: No such module "Lang". is a Latinate loan from Old French Script error: No such module "Lang". ~ Script error: No such module "Lang".[6] which may have been from Medieval Latin Script error: No such module "Lang". (another English spelling), Script error: No such module "Lang"., along with Spanish Script error: No such module "Lang". (> Script error: No such module "Lang".) and Italian Script error: No such module "Lang"., in the 9th century, and from Arabic Script error: No such module "Lang". Template:Transliteration ~ Template:Transliteration ~ Template:Transliteration which is attested in Ibn Sayyar al-Warraq's Kitāb al-Ṭabīkh among many examples,[6][7][8] from Middle Persian bwlk' (bōrag), which yielded Persian Script error: No such module "Lang". bure.

The words tincal and tincar were adopted into English in the 17th century from Malay Script error: No such module "Lang". and from Urdu/Persian/Arabic Template:Script Template:Transliteration; thus the two forms in English. These all appear to be related to the Sanskrit Script error: No such module "Lang". Template:Transliteration.[9][10]

Chemistry

File:Borax-unit-cell-3D-balls.png
The structure of borax according to X-ray crystallography.

From a chemical perspective, borax contains the Template:Chem2 ion. In this structure, there are two four-coordinate boron centers and two three-coordinate boron centers.

It is a proton conductor at temperatures above Template:Convert. Conductivity is maximum along the b-axis.[11]

Borax is also easily converted to boric acid and other borates, which have many applications. Its reaction with hydrochloric acid to form boric acid is:

Template:Chem2

Borax is sufficiently stable to find use as a primary standard for acid-base titrimetry.[12]Template:Rp

Molten borax dissolves many metal oxides to form glasses. This property is important for its uses in metallurgy and for the borax bead test of qualitative chemical analysis.

Borax is soluble in a variety of solvents; however, it is notably insoluble in ethanol.[1]

Solubility of borax in some solvents[13]
Organic solvent Temperature
°C (°F) 		Borax % by weight
in saturated solution
Glycerol 98.5% 20 (68) 52.60
Glycerol 86.5% 20 (68) 47.19
Ethylene glycol 25 (77) 41.60
Diethylene glycol 25 (77) 18.60
Methanol 25 (77) 19.90
Aqueous ethanol 46.5% 15.5 (60) 2.48
Acetone 25 (77) 0.60
Ethyl acetate 25 (77) 0.14
Solubility of borax in water[13]
Temperature
°C (°F) 		Borax % by weight in saturated solution
0 (32) 1.99
5 (41) 2.46
10 (50) 3.09
15 (59) 3.79
20 (68) 4.70
25 (77) 5.80
30 (86) 7.20
35 (95) 9.02
40 (104) 11.22
45 (113) 14.21
50 (122) 17.91
55 (131) 23.22
60 (140) 30.32
65 (149) 33.89
70 (158) 36.94
75 (167) 40.18
80 (176) 44.31
85 (185) 48.52
90 (194) 53.18
95 (203) 58.94
100 (212) 65.63

The term borax properly refers to the so-called "decahydrate" Template:Chem2, but that name is not consistent with its structure. It is actually octahydrate. The anion is not tetraborate Template:Chem2 but tetrahydroxy tetraborate Template:Chem2,[11] so the more correct formula should be Template:Chem2. However, the term may be applied also to the related compounds. Borax "pentahydrate" has the formula Template:Chem2, which is actually a trihydrate Template:Chem2. It is a colorless solid with a density of Template:Val that crystallizes from water solutions above Template:Convert in the rhombohedral crystal system. It occurs naturally as the mineral tinkhanite.[14] It can be obtained by heating the "decahydrate" above Template:Convert.[15] Borax "dihydrate" has the formula Template:Chem2, which is actually anhydrous, with the correct formula Template:Chem2. It can be obtained by heating the "decahydrate" or "pentahydrate" to above Template:Convert.[15] Anhydrous borax is sodium tetraborate proper, with formula Template:Chem2. It can be obtained by heating any hydrate to Template:Convert.[15] It has one amorphous (glassy) form and three crystalline forms – α, β, and γ, with melting points of Template:Convert, Template:Convert and Template:Convert respectively. Template:Chem2 is the stable form.[15]

Natural sources

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File:Borax ball.jpg
Borax "cottonball" Template:Explain

Borax occurs naturally in evaporite deposits produced by the repeated evaporation of seasonal lakes. The most commercially important deposits are found in: Boron, California; and Searles Lake, California. Also, borax has been found at many other locations in the Southwestern United States, the Atacama Desert in Chile, newly discovered deposits in Bolivia, and in Tibet and Romania. Borax can also be produced synthetically from other boron compounds.[16]

Naturally occurring borax (known by the trade name Rasorite–46 in the United States and many other countries) is refined by a process of recrystallization.[17]

File:Hauling Borax, Death Valley, 1904.jpg
Traction steam engine hauling borax, Death Valley National Park, California, 1904

Uses

File:Borax.jpg
Borax-based laundry detergent

Borax is used in pest control solutions because it is toxic to ants and rats. Because it is slow-acting, worker ants will carry the borax to their nests and poison the rest of the colony.[18] Borax is more effective than zinc borate for termite control but a 1997 paper concluded that exposing at least 10% of the total colony population was needed for effective treatment. In Japan the practice of laying newspapers treated with o-boric acid and borax under buildings has been effective in controlling Coptotermes formosanus and Reticulitermes speratus populations. Decaying wood treated with 0.25 to 0.5 percent DOT was also found to be effective for baiting Heterotermes aureus populations. The paper concluded: "Borate baits would undoubtably be helpful in the long-term, but do not appear sufficient as a sole method of structural protection."[19]

Borax is used in various household laundry and cleaning products,[20][21] including the 20 Mule Team Borax laundry booster, Boraxo powdered hand soap, and some tooth bleaching formulas.[22][23]

Borate ions (commonly supplied as boric acid) are used in biochemical and chemical laboratories to make buffers, e.g. for polyacrylamide gel electrophoresis of DNA and RNA, such as TBE buffer (borate buffered tris-hydroxymethylaminomethonium)[24][25] or the newer SB buffer or BBS buffer (borate buffered saline) in coating procedures. Borate buffers (usually at pH 8) are also used as preferential equilibration solutions in dimethyl pimelimidate (DMP) based crosslinking reactions.[26]

Borax as a source of borate has been used to take advantage of the co-complexing ability of borate with other agents in water to form complex ions with various substances. Borate and a suitable polymer bed are used to chromatograph non-glycated hemoglobin differentially from glycated hemoglobin (chiefly HbA1c), which is an indicator of long-term hyperglycemia in diabetes mellitusScript error: No such module "Unsubst".

Borax alone does not have a high affinity for hardness cations, although it has been used for water softening. A general chemical equation for water softening is (R is the dissolved cation, usually calcium or magnesium):

Template:Chem2

The sodium ions introduced do not make water "hard". This method is suitable for removing both temporary and permanent types of hardness.Script error: No such module "Unsubst".

A mixture of borax and ammonium chloride is used as a flux when welding iron and steel. It lowers the melting point of the unwanted iron oxide (scale), allowing it to run off. Borax is also mixed with water as a flux when soldering jewelry metals such as gold or silver, where it allows the molten solder to wet the metal and flow evenly into the joint.[27] Borax is also a flux for "pre-tinning" tungsten with zinc, making the tungsten soft-solderable.[28] Borax is often used as a flux for forge welding.[29]

File:Borax wagons.jpg
Old steam tractor with borax wagons, Death Valley National Park

In artisanal gold mining, borax is sometimes used as part of a process known as the borax method (as a flux) meant to eliminate the need for toxic mercury in the gold extraction process, although it cannot directly replace mercury. Borax was reportedly used by gold miners in parts of the Philippines in the 1900s.[30][31] There is evidence that, in addition to reducing the environmental impact, this method achieves better gold recovery for suitable ores and is less expensive. This borax method is used in northern Luzon in the Philippines, but miners have been reluctant to adopt it elsewhere for reasons that are not well understood.[32] The method has also been promoted in Bolivia[33] and Tanzania.[34]

A rubbery polymer sometimes called Slime, Flubber, "gluep" or "glurch" (or erroneously called Silly Putty, which is based on silicone polymers), can be made by cross-linking polyvinyl alcohol with borax.[35] Making flubber from polyvinyl acetate-based glues, such as Elmer's Glue, and borax is a common elementary science demonstration.[36][37]

Borax, given the E number E285, is used as a food additive but this use is banned in some countries, such as Australia, China, Thailand and the United States.[38] As a consequence, certain foods, such as caviar, produced for sale in the United States contain higher levels of salt to assist preservation.[39] In addition to its use as a preservative, borax imparts a firm, rubbery texture to food. In China, borax (Template:Lang-zh or Template:Lang-zh) has been found in foods including wheat and rice noodles named lamian (Template:Lang-zh), shahe fen (Template:Lang-zh), char kway teow (Template:Lang-zh), and chee cheong fun (Template:Lang-zh)Template:Clarify[40] In Indonesia, it is a common, but forbidden,[41] additive to such foods as noodles, bakso (meatballs), and steamed rice.

File:Boron mine pit.jpg
Rio Tinto borax mine pit, Boron, California

Other

Other uses include:

Toxicity

According to one study, borax is not acutely toxic. Its LD50 (median lethal dose) score is tested at 2.66 g/kg in rats, meaning that a significant dose of the chemical is needed to cause severe symptoms or death.Script error: No such module "Unsubst".

The lethal dose is not necessarily the same for humans; human studies in three borate exposure-rich comparison groups (U.S. Borax mine and production facility workers, Chinese boron workers, Turkish residents living near boron rich regions) produced no indicators of developmental toxicity in blood and semen tests. The highest estimated exposure was 5 mg B/kg/day, likely due to eating in contaminated workplaces, more than 100 times the average daily exposure.[62]

Borax is absorbed poorly through intact skin, although fatalities have been recorded in persistent treatment of rashes and open wounds with boric acid-containing ointments and bath solutions. Borax is readily absorbed orally, well above 90%, and mostly excreted through the urine. Fatal cases attributed to ingestion include small children mistakenly drinking pesticides or suicide attempts with large volumes of crystals. No genotoxicity or carcinogenicity has been recorded in studies.[63]

Borax has been in use as an insecticide in the United States with various restrictions since 1946. All restrictions were removed in February 1986 due to the low toxicity of borax, as reported in two EPA documents relating to boric acid and borax.[64][65]

<templatestyles src="Template:Blockquote/styles.css" />

EPA has determined that, because they are of low toxicity and occur naturally, boric acid and its sodium salts should be exempted from the requirement of a tolerance (maximum residue limit) for all raw agricultural commodities.[64]

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Although it cited inconclusive data, a re-evaluation in 2006 by the EPA still found that "There were no signs of toxicity observed during the study and no evidence of cytotoxicity to the target organ."[66] In the reevaluation, a study of toxicity due to overexposure was checked and the findings were that "The residential handler inhalation risks due to boric acid and its sodium salts as active ingredients are not a risk concern and do not exceed the level of concern", but that there could be some risk of irritation to children inhaling it if used as a powder for cleaning rugs.

Overexposure to borax dust can cause respiratory irritation, while no skin irritation is known to exist due to external borax exposure. Ingestion may cause gastrointestinal distress including nausea, persistent vomiting, abdominal pain, and diarrhea. Effects on the vascular system and human brain include headaches and lethargy but are less frequent. In severe cases, a "beefy" red rash affecting the palms, soles, buttocks and scrotum has occurred.[67]

Borax was added to the Substance of Very High Concern (SVHC) candidate list on December 16, 2010. The SVHC candidate list is part of the EU Regulations on the Registration, Evaluation, Authorisation and Restriction of Chemicals 2006 (REACH), and the addition was based on the revised classification of borax as toxic for reproduction category 1B under the CLP Regulations. Substances and mixtures imported into the EU which contain borax are now required to be labelled with the warnings "May damage fertility" and "May damage the unborn child".[68] It was proposed for addition to REACH Annex XIV by the ECHA on July 1, 2015.[69] If this recommendation is approved, all imports and uses of borax in the EU will have to be authorized by the ECHA.Script error: No such module "Unsubst".Script error: No such module "Check for unknown parameters".

A review of the boron toxicity (as boric acid and borates) published in 2012 in the Journal of Toxicology and Environmental Health concluded: "It clearly appears that human B [boron] exposures, even in the highest exposed cohorts, are too low to reach the blood (and target tissue) concentrations that would be required to exert adverse effects on reproductive functions."[70] A draft risk assessment released by Health Canada in July 2016 has found that overexposure to boric acid has the potential to cause developmental and reproductive health effects. Since people are already exposed to boric acid naturally through their diets and water, Health Canada advised that exposure from other sources should be reduced as much as possible, especially for children and pregnant women.

The concern is not with any one product, but rather multiple exposures from a variety of sources. With this in mind, the department also announced that certain pesticides that contain boric acid, which are commonly used in homes, will have their registrations cancelled and be phased out of the marketplace. As well, new, more protective label directions are being introduced for other boric acid pesticides that continue to be registered in Canada (for example, enclosed bait stations and spot treatments using gel formulations).[71]

See also

Explanatory footnotes

Template:Notelist

References

  1. ↑ a b c Script error: No such module "citation/CS1".
  2. ↑ Script error: No such module "citation/CS1".
  3. ↑ a b Script error: No such module "citation/CS1".
  4. ↑ Template:Cite magazine. The article states that the distance between Columbus, Nevada and Wadsworth, Nevada is "about 360 miles" whereas today the distance on modern roads is about 160 miles.
  5. ↑ Script error: No such module "citation/CS1".
  6. ↑ a b Script error: No such module "template wrapper". Template:OEDsub
  7. ↑ Template:Cite dictionary
  8. ↑ Script error: No such module "citation/CS1".
  9. ↑ Template:OED
  10. ↑ Chemical Age of India, Vol. 37, No.10 & 11 (1976)Template:Full citation needed
  11. ↑ a b Script error: No such module "Citation/CS1".
  12. ↑ Template:VogelQuantitative
  13. ↑ a b Borax decahydrate. borax.com
  14. ↑ Script error: No such module "Citation/CS1".
  15. ↑ a b c d Script error: No such module "Citation/CS1".
  16. ↑ Script error: No such module "citation/CS1".
  17. ↑ Script error: No such module "Citation/CS1".
  18. ↑ Script error: No such module "Citation/CS1".
  19. ↑ Script error: No such module "Citation/CS1".
  20. ↑ Template:CPID
  21. ↑ Script error: No such module "citation/CS1".
  22. ↑ Script error: No such module "citation/CS1".
  23. ↑ Script error: No such module "citation/CS1".
  24. ↑ Script error: No such module "Citation/CS1".
  25. ↑ Script error: No such module "Citation/CS1".
  26. ↑ Script error: No such module "citation/CS1".
  27. ↑ Script error: No such module "citation/CS1".
  28. ↑ Script error: No such module "Citation/CS1".
  29. ↑ Script error: No such module "Citation/CS1".
  30. ↑ Script error: No such module "citation/CS1".
  31. ↑ Script error: No such module "citation/CS1".
  32. ↑ Script error: No such module "Citation/CS1".
  33. ↑ Script error: No such module "Citation/CS1".
  34. ↑ Script error: No such module "Citation/CS1".
  35. ↑ Script error: No such module "citation/CS1".
  36. ↑ Script error: No such module "citation/CS1".
  37. ↑ Script error: No such module "citation/CS1".
  38. ↑ Script error: No such module "citation/CS1".
  39. ↑ Script error: No such module "citation/CS1".
  40. ↑ Script error: No such module "citation/CS1".
  41. ↑ Script error: No such module "citation/CS1".
  42. ↑ Script error: No such module "citation/CS1".
  43. ↑ a b Script error: No such module "citation/CS1".
  44. ↑ Script error: No such module "citation/CS1".
  45. ↑ Script error: No such module "citation/CS1".
  46. ↑ Script error: No such module "citation/CS1".
  47. ↑ Script error: No such module "citation/CS1".
  48. ↑ Script error: No such module "citation/CS1".
  49. ↑ Script error: No such module "citation/CS1".
  50. ↑ Script error: No such module "citation/CS1".
  51. ↑ Template:Cite patent
  52. ↑ Script error: No such module "citation/CS1".
  53. ↑ Script error: No such module "citation/CS1".
  54. ↑ Script error: No such module "citation/CS1".
  55. ↑ Script error: No such module "citation/CS1".
  56. ↑ Script error: No such module "citation/CS1".
  57. ↑ Script error: No such module "citation/CS1".
  58. ↑ Script error: No such module "citation/CS1".
  59. ↑ Script error: No such module "citation/CS1".
  60. ↑ Script error: No such module "Citation/CS1".
  61. ↑ Script error: No such module "Citation/CS1".
  62. ↑ Script error: No such module "citation/CS1".
  63. ↑ Script error: No such module "Citation/CS1".
  64. ↑ a b Script error: No such module "citation/CS1".
  65. ↑ Script error: No such module "citation/CS1".
  66. ↑ Script error: No such module "citation/CS1".
  67. ↑ Script error: No such module "citation/CS1".
  68. ↑ Member state committee draft support document for identification of disodium tetraborate, anhydrous as a substance of very high concern because of its CMR properties. Adopted on June 9, 2010. Echa.europa.eu. Retrieved on February 17, 2012.
  69. ↑ Recommendation of the European Chemicals Agency of 1 July 2015 for the inclusion of substances in Annex XIV to REACH (List of Substances subject to Authorisation) Template:Webarchive Echa.europa.eu. Retrieved on July 6, 2015.
  70. ↑ Script error: No such module "Citation/CS1".
  71. ↑ Script error: No such module "citation/CS1".

Cite error: <ref> tag with name "haynes2011" defined in <references> is not used in prior text.
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Cite error: <ref> tag with name "PGCH58" defined in <references> is not used in prior text.

External links

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