Dichlorodiphenyldichloroethylene

Dichlorodiphenyldichloroethylene (DDE) is a chemical compound formed by the loss of hydrogen chloride (dehydrohalogenation) from DDT, of which it is one of the more common breakdown products.[1] Due to DDT’s massive prevalence in society and agriculture during the mid 20th century, DDT and DDE are still widely seen in animal tissue samples.[2] DDE is particularly dangerous because it is fat-soluble like other organochlorines; thus, it is rarely excreted from the body, and concentrations tend to increase throughout life. The major exception is the excretion of DDE in breast milk, which transfers a substantial portion of the mother's DDE burden to the young animal or child.[3] Along with accumulation over an organism's lifetime, this stability leads to bioaccumulation in the environment, which amplifies DDE’s negative effects.

Dichlorodiphenyldichloroethylene
Names
IUPAC name
1,1-dichloro-2,2-bis(4-chlorophenyl)ethene
Preferred IUPAC name
1,1′-(2,2-dichloroethene-1,1-diyl)bis(4-chlorobenzene)
Other names
Dichlorodiphenyldichloroethylene
Identifiers
3D model (JSmol)
Abbreviations p,p'-DDE
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.713
KEGG
UNII
Properties
C14H8Cl4
Molar mass 318.02 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Synthesis

DDE is created by dehydrohalogenation of DDT. The loss of HCl results in a double bond on the central (previously quaternary) carbon atoms.

Degradation of DDT to form DDE by an elimination of HCl

Toxicity

DDE has been shown to be toxic to rats at 79.6 mg/kg.[4] DDE and its parent, DDT, are reproductive toxicants for certain birds species, and major reasons for the decline of the bald eagle,[5] brown pelican[6] peregrine falcon, and osprey.[7] These compounds cause egg shell thinning in susceptible species, which leads to the birds’ crushing their eggs instead of incubating them, due to the latter’s lack of resistance.[8] Birds of prey, waterfowl, and song birds are more susceptible to eggshell thinning than chickens and related species, and DDE appears to be more potent than DDT.[7]

A research shows that an elevated blood levels of DDEs (also of other toxic molecule from nonstick cookware, and fire retardants) have been tied to an increased risk for celiac disease in young people.[9]

Mechanism

The biological mechanism for the thinning is not entirely known, but it is believed that p,p'-DDE impairs the shell gland's ability to excrete calcium carbonate onto the developing egg.[7][10][11][12][13] Multiple mechanisms may be at work, or different mechanisms may operate in different species.[7] Some studies have shown that although DDE levels have fallen dramatically, eggshell thickness remains 10–12 percent thinner than before DDT was first used.[14]

Some studies have indicated that DDE is an endocrine disruptor[15] and contributes to breast cancer, but more recent studies provide strong evidence that there is no relationship between DDE exposure and breast cancer.[16] What is more clear is that DDE is a weak androgen receptor antagonist and can produce male genital tract abnormalities.[17]

gollark: So why are there *two*?
gollark: What's the difference between the AR and NDAR?
gollark: DOWN WITH SICKNESS!
gollark: I wonder what happened to the hatcheries. This is weird.
gollark: *hatchling* soon though I forgot about it until now.

See also

References
  1. ATSDR - Public Health Statement: DDT, DDE, and DDD
  2. Walker, K. C.; Goette, M. B.; Batchelor, G. S. (1954). "Pesticide Residues in Foods, Dichlorodiphenyltrichloroethane and Dichlorodiphenyldichloroethylene Content in Prepared Foods". Journal of Agricultural and Food Chemistry. 2 (20): 1034–1037. doi:10.1021/jf60040a006.
  3. Waliszewski, SM; Melo-Santiesteban, G; Villalobos-Pietrini, R; Gómez-Arroyo, S; Amador-Muñoz, O; Herrero-Mercado, M; Carvajal, O (2009). "Breast milk excretion Kinetic of b-HCH, pp'DDE and pp'DDT". Bull Environ Contam Toxicol. 83 (6): 869–73. doi:10.1007/s00128-009-9796-3. PMID 19551328.
  4. NIST DDE MSDS
  5. Stokstad, E (2007). "Species conservation. Can the bald eagle still soar after it is delisted?". Science. 316 (5832): 1689–90. doi:10.1126/science.316.5832.1689. PMID 17588911.
  6. "Endangered and Threatened Wildlife and Plants; 12-Month Petition Finding and Proposed Rule To Remove the Brown Pelican (Pelecanus occidentalis) From the Federal List of Endangered and Threatened Wildlife; Proposed Rule," Fish and Wildlife Service, U.S. Department of the Interior, February 20, 2008. 73 FR 9407
  7. ATSDR - Toxicological Profile: DDT, DDE, DDD
  8. "California Wild Spring 1994 - Peregrine Falcons". Archived from the original on 2007-06-16. Retrieved 2007-03-21.
  9. https://medicalxpress.com/news/2020-05-celiac-disease-linked-common-chemical.html
  10. Recovery Plan for the California Condor, U.S. Fish and Wildlife Service, April 1996, page 23
  11. "DDE concentration and percent eggshell thinning in Double-crested Conmorant eggs(North Channel, Lake Huron, Ont.)". Archived from the original on 2007-06-28. Retrieved 2009-04-15.
  12. Guillette, Louis J., Jr. (2006). "Endocrine Disrupting Contaminants" (PDF). Archived from the original (PDF) on 2009-03-25. Retrieved 2007-02-02.
  13. Lundholm, C.E. (1997). "DDE-Induced eggshell thinning in birds". Comp Biochem Physiol C Pharmacol Toxicol Endocrinol. 118 (2): 113–28. doi:10.1016/S0742-8413(97)00105-9. PMID 9490182.
  14. Division of Environmental Quality Archived 2008-03-03 at the Wayback Machine
  15. Chemical fact sheet: Organochlorine - The Breast Cancer Fund Archived 2006-10-09 at the Wayback Machine
  16. Questions about Endocrine Disruptors
  17. Longnecker, M. P.; Gladen, B. C.; Cupul-Uicab, L. A.; Romano-Riquer, S. P.; Weber, J.-P.; Chapin, R. E.; Hernandez-Avila, M. (2007). "In utero exposure to the antiandrogen 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) in relation to anogenital distance in male newborns from Chiapas, México". American Journal of Epidemiology. 165 (9): 1015–22. doi:10.1093/aje/kwk109. PMC 1852527. PMID 17272288.


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