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Hormone Disrupters

While the environmental effects of persistent organic pollutants (POPs) such as halogenated hydrocarbon pesticides (DDT, dieldrin, etc.), furans, dioxins and PCBs have long been known (see POPs), there has been a growing body of recent evidence that some of them may mimic or inhibit hormones and interfere with natural regulatory processes even in extremely low doses.

Their effect on wildlife is well documented and includes the feminisation of male foetuses, reproductive dysfunctions, behavioural changes and developmental problems. Marine mammal and amphibian populations around the world have declined, possibly due to a lack in fertile males, or males full stop. Studies of alligators in Florida and of polar bears on the Svalbard archipelago found unusual numbers born with a set of partially developed male and female sexual organs, abnormally small genitals in males and a shift in sex ratios (see Declining sex ratios below). And in the Great Lakes, herring gull nests were found with double the normal number of eggs, which were unfertilised and tended by pairs of female birds, because the males had lost interest in mating and rearing young. (Colborn et al., 1996)

Their effects on humans seem to parallel those found in wildlife  and may include ovarian, breast, testicular and prostate cancers, reduced sperm counts in men (Auger et al, 1995; Kelce et al, 1995), depressed immunity, a rise in early puberty, and impaired foetal development leading
possibly to smaller babies, reduced intelligence, hyperactivity and violence (Colborn et al, 1996; Mathews, 1996; Meadows, 1996; Repetto and Baliga, 1996).

Oestrogen-mimickers are found in a broad range of products, from pesticides to solvents and detergents, industrial chemicals or unintended byproducts of industrial processes. Once released
into the environment, people are exposed to them in foods such as milk, soya beans, fish and animal fats, and in drinking water. There are pressures to ban the most dangerous chemicals.


Auger, Jacques, J.M. Kunstmann, F. Czyglik and P. Jouannet. 1995. "Decline in semen quality among fertile men in Paris during the past 20 years." New England Journal of Medicine 332(5):281-285. 2 February 1995.

Colborn, Theo, Dianne Dumanoski, and John Peterson Myers.  1996.  Our
Stolen Future.  Dutton, New York.

Kelce, William R., C.R. Stone, S.C. Laws, L.E. Gray, J.A. Kemppainen and E.M.
Wilson. 1995. Persistent DDT metabolite P,P'-DDE is a potent androgen
receptor antagonist." Nature 375:581-585. 15 June 1995. Kiernan,
Vincent. 1995. "Forest grows tall on radio waves". New Scientist, 14 January 1995, p5.

Mathews, Jessica. 1996.  "Overlooking the 'POPs' Problem."  Washington
Post, 11 March 1996.

Meadows, Donella H.  1996.  "Humans, an Endangered Species?" 
International Herald Tribune, 24/25 February 1996.

Repetto, Robert, and Sanjay Baliga. 1996. Pesticides and the Immune System:
The Public Health Risks. World Resources Institute, Washington,


Emerging Issues


UNEP/DEWA/Earthwatch 1996-2003