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. 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.
Source: Wikipedia — Dichlorodiphenyldichloroethylene (CC BY-SA 4.0)