Endosulfan

Endosulfan is a neurotoxic organochlorine insecticide of the cyclodiene

family of pesticides. It is highly toxic and an endocrine disruptor,

and it is banned in several countries including Germany, Norway, and

the Philippines. It is still used extensively in many countries

including the US and India. It is made by Bayer CropScience,

Makhteshim-Agan, and Drexel Company among other, and sold under the

tradenames Thionex, Thiodan, Phaser, and Benzoepin. Uses


Endosulfan is used in agriculture around the world to control insect

pests including aphids, leafhoppers, Colorado potato beetles, cabbage

worms, and other pests. It has also seen use in tse-tse fly control, in

wood preservation, and in home gardening. The World Health Organization

estimated world wide annual production to be about 20 million lbs in

the early 1980s.In India, more endosulfan is produced than any

other pesticide except mancozeb and monocrotophos, with almost 180

million lbs manufacturerd in 1999-2000.

In the US, endosulfan is registered only for agricultural use, where it

is used extensively on cotton, potatoes, and apples according to the

Environmental Protection Agency (EPA). The EPA estimates that 1.38

million lbs of endosulfan were used annually from 1987 to 1997. In

California, annual use of endosulfan dropped from 230,000 lbs in 1995

to just 83,000 lbs in 2005.

Health Effects

Endosulfan is one of the more toxic pesticides on the market today,

responsible for many fatal pesticide poisoning incidents around the

world. Endosulfan is also a xenoestrogen—a synthetic substance that

imitates or enhances the effect of estrogens—and it can act as an

endocrine disruptor, causing reproductive and developmental damage in

both animals and humans. Whether endosulfan can cause cancer is

debated.

Endosulfan and Cancer

Endosulfan is not listed as known, probable, or possible carcinegon by

the EPA, IARC, or other agencies. There are no epidemiological studies

linking exposure to endosulfan specifically to cancer in humans, but in

vitro assays have shown that endosulfan can promote proliferation of

human breast cancer cells.[15] Evidence of cancinogenicity in animals

is mixed.

Endosulfan in the Environment

According to the EPA endosulfan breaks down in to endosulfan sulfate

and endosulfan diol, both of which have "structures similar to the

parent compound and are also of toxicological concern…The estimated

half-lives for the combined toxic residues (endosulfan plus endosulfan

sulfate) [range] from roughly 9 months to 6 years." The EPA concluded

that, "[b]ased on environmental fate laboratory studies, terrestrial

field dissipation studies, available models, monitoring studies, and

published literature, it can be concluded that endosulfan is a very

persistent chemical which may stay in the environment for lengthy

periods of time, particularly in acid media." The EPA also concluded

that "[e]ndosulfan has relatively high potential to bioaccumulate in

fish.

The EPA recommends not more than 74 ppb (part per billion) in lakes,

streams, or rivers, and not more than 0.1 – 2 ppm (parts per million)

on surfaces of agricultural products