Methoxychlor

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description <templatestyles src="Chembox/styles.css"/>

Template:Chembox image cellTemplate:Chembox image cellTemplate:Chembox AllOtherNamesTemplate:Chembox headerbarTemplate:Chembox IndexlistTemplate:Chembox JmolTemplate:Chembox ChEMBLTemplate:Chembox ECHATemplate:Chembox E numberTemplate:Chembox IUPHAR ligandTemplate:Chembox UNIITemplate:Chembox CompToxTemplate:Chembox headerbarTemplate:Chembox SolubilityInWaterTemplate:Chembox headerbarTemplate:Chembox Lethal amounts (set)Template:Chembox setHeaderTemplate:Chembox setDatarowTemplate:Chembox setDatarowTemplate:Chembox setDatarowTemplate:Chembox Datapage checkTemplate:Chembox Footer
Methoxychlor
Template:Longitem Template:Unbulleted list
Abbreviations DMDT
ChEBI Template:Unbulleted list
ChemSpider Template:Unbulleted list
DrugBank Template:Unbulleted list
EC Number Template:Unbulleted list
KEGG Template:Unbulleted list
Template:Longitem Template:Unbulleted list
RTECS number Template:Unbulleted list
Script error: No such module "collapsible list".
Script error: No such module "collapsible list".
Template:Longitem Template:Chembox Elements/molecular formula
Molar mass 345.65 g/mol
Appearance Colorless to light-yellow crystals
Odor Slight, fruity odor
Density 1.41 g/cm3 (20°C)[1]
Melting point Template:Chembox CalcTemperatures
Boiling point Template:Chembox CalcTemperatures

Template:Chembox Footer/trackingScript error: No such module "TemplatePar".Template:Short description

Methoxychlor is a synthetic organochloride insecticide, now obsolete. Tradenames for methoxychlor include Chemform, Maralate, Methoxo, Methoxcide, Metox, and Moxie.

Usage

Methoxychlor was used to protect crops, ornamentals, livestock, and pets against fleas, mosquitoes, cockroaches, and other insects. It was intended to be a replacement for DDT, but has since been banned for use as a pesticide based on its acute toxicity, bioaccumulation, and endocrine disruption activity.[3]

The amount of methoxychlor in the environment changes seasonally due to its use in farming and foresting. It does not dissolve readily in water, so it is mixed with a petroleum-based fluid and sprayed, or used as a dust. Sprayed methoxychlor settles on the ground or in aquatic ecosystems, where it can be detected in sediments.[4] Its degradation may take many months. Methoxychlor is ingested and absorbed by living organisms, and it accumulates in the food chain. Some metabolites may have unwanted side effects.

Banned

The use of methoxychlor as a pesticide was banned in the United States in 2003[5] and in the European Union in 2002.[6]

Health and Environmental Impacts

The EPA lists methoxychlor as "a persistent, bioaccumulative, and toxic (PBT) chemical by the EPA Toxics Release Inventory (TRI) program",[3] and as such it is a waste minimization priority chemical. The 2023 Conference of the Parties of the United Nations Stockholm Convention on Persistent Organic Pollutants decided to eliminate the use of methoxychlor, by listing this chemical in Annex A to the Convention.[7]

Human exposure

Human exposure to methoxychlor occurs via air, soil, and water,[8] primarily in people who work with the substance or who are exposed to air, soil, or water that has been contaminated. It is unknown how quickly and efficiently the substance is absorbed by humans who have been exposed to contaminated air or via skin contact.[8] In animal models, high doses can lead to neurotoxicity.[8] Some methoxychlor's metabolites have estrogenic effects in adult and developing animals before and after birth.[8] One studied metabolite is 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE) which shows reproductive toxicity in an animal model by reducing testosterone biosynthesis.[9][10] Such effects adversely affect both the male and female reproductive systems. It is expected that this "could occur in humans" but has not been proven.[8] While one study has linked methoxychlor to the development of leukemia in humans, most studies in animals and humans have been negative, thus the EPA has determined that it is not classifiable as a carcinogen. The EPA indicates that levels above the Maximum Contaminant Level of 40 ppb "cause" central nervous depression, diarrhea, damage to liver, kidney, and heart, and - by chronic exposure - growth retardation.[3]

Little information is available regarding effects on human pregnancy and children, but it is assumed from animals studies that methoxychlor crosses the placenta, and it has been detected in human milk[8] Exposure to children may be different than in adults because they tend to play on the ground, further, their reproductive system may be more sensitive to the effects of methoxychlor as an endocrine disruptor.Script error: No such module "Unsubst".

Food contamination may occur at low levels and it is recommended to wash all foods.[8] A number of hazardous waste sites are known to contain methoxychlor.

Maximum pesticide residue limits for the EU/UK are set at 0.01 mg/kg for oranges and 0.01 mg/kg for apples.

See also

References

<templatestyles src="Reflist/styles.css" />

  1. a b c d e Script error: No such module "citation/CS1".
  2. Template:IDLH
  3. a b c Script error: No such module "citation/CS1".
  4. Script error: No such module "Citation/CS1".
  5. Script error: No such module "citation/CS1".
  6. Script error: No such module "citation/CS1".
  7. Script error: No such module "citation/CS1".
  8. a b c d e f g Script error: No such module "citation/CS1"., accessed 08-22-2008
  9. Script error: No such module "Citation/CS1".
  10. Script error: No such module "Citation/CS1".

Script error: No such module "Check for unknown parameters".

External links

Script error: No such module "Navbox". Template:Estrogen receptor modulators Template:Xenobiotic-sensing receptor modulators