• Society of Environmental Toxicology and Chemistry Annual Meeting Summary (20 August 02)
• e.hormone 2001 Conference Summary (3 July 02)
• Environmental hormone news (3 August 02)
• Conference kiosk (12 Aug 02)
• Media coverage (2 August 02)

New Research: July/August 2002

• Combinations enhance action. Combinations of xenoestrogens at concentrations below their observed effects levels increased 17-beta estradiol action, according to research published online in Environmental Health Perspectives. The 11 xenoestrogens tested caused an additive effect that increased estrogenic responses in a human alpha ER yeast reporter gene assay. Laboratory experiments confirmed initial computer model predictions. The results suggest that chemical levels well below those that cause observable effects may potentially affect wildlife and humans. (Rajapakse, N, E Silva, and A Kortenkamp. 2002 Combining xenoestrogens at levels below individual no-observed-effect concentrations dramatically enhances steroid hormone action. Environmental Health Perspectives, 110(9, September): Online 12 August 2002.)

• Growth promoters cross placenta. Three agents used to promote growth in animals can cross the mammalian placenta and enter fetal tissue exposing unborn and developing fetuses to the substances, according to research published in August's issue of Xenobiotica. Pregnant rabbits were treated with trenbolone acetate, zeranol, or melengestrol acetate beginning at gestation day 14. Using HPLC/ELISA analytical methods, the researcher found varying amounts of the substances and their metabolites in tissue taken from the mothers and the fetuses on gestation day 27. (Lange, IG et al. 2002 Quantitative assessment of fetal exposure to trenbolone acetate, zeranol, and melengestrol acetate, following maternal dosing in rabbits. Xenobiotica, 32(8, August): 641-651.)

Headlines: August 2002

• Global Assessment of the State-of-the-Science of Endocrine Disruptors. Report. International Programme on Chemical Safety (IPCS). 134 pp. 12 August 2002. Online at http://www.who.int/pcs/emerg_site/edc/global_edc_TOC.htm.

• Endocrine disrupting chemicals: New publication shows need for further research World Health Organization Web Site (Online), 12 August 2002.

• Duckworth, L. Alarm at gender-bending chemicals Independent.co.uk (Online), 12 August 2002.

• Panel finds no danger from playground wood Environment News Service (Online), 8 August 2002.

• Christensen, DE. Drugs in the waters. BioMedNet (Online), 7 August 2002. While low concentrations of individual drugs commonly found in sewage, surface, and other water produced stunted growth and some reproductive effects, mixtures of the drugs and their metabolites wiped out 90 percent of a population of the small, freshwater creature called daphnia. In addition, one-third of the animals were deformed after exposure to smaller mixture levels indicating that mixtures have some sort of synergistic effects. Researcher Colleen Flaherty of the University of Wisconsin, Madison, presented her results at the Ecological Society of America meetings in Tucson, Arizona. Low concentrations (10 parts per billion) of cholesterol-lowering drugs, antibiotics, and antidepressants commonly found in water stunted growth and produced more male offsprings in the exposed brood. If exposed throughout life, however, the animals adapt and compensate to the pollutants. Daphnia are tiny, ecologically-important freshwater organisms at the low end of the food chain. They eat algae and are eaten by fish and other larger animals.

• Toy, VS. Long island study sees no cancer tie to pesticides New York Times (Online), 6 August 2002.

• Lazaroff, C. No link between organochlorines, breast cancer Environment News Service (Online), 6 August 2002.

• EPA, enviros disagree on pesticide reassessment Environment News Service (Online), 5 August 2002.

• Raloff, J. 2002. Study links dioxin to breast cancer. Science News, 162(3 August 2002):77. A new study published in July's Environmental Health Perspectives finds that young women exposed to high concentrations of dioxin have a higher risk of getting breast cancer later in life. In this study, each 10-fold increase in blood dioxin levels doubled breast cancer risk. Of 981 women exposed to large amounts of TCDD after a plant explosion in Seveso, Italy, in 1976, 15 developed breast cancer at an average age of 45. At the time of the disaster, the women, who were all under 40 years old, had very high blood concentrations of dioxin.

Government (1 Aug 02)

1. For program overview, see Organophosphate pesticide tolerance reassessment and reregistration web site.

2. Comment period for the revised cumulative risk assessment for the organophosphate pesticides is extended to August 21, 2002, from July 22, 2002. A June 20 Federal Register notice announced the initial availability and deadline. The revised cumulative risk assessment documents are available atwww.epa.gov/pesticides/cumulative/rra-op/. See the July 22 Federal Register notice (DOCID: fr22jy02-64). (Posted 1 Aug 02)

3. Organophosphate pesticides (OP): Reassessment of 47 non-contributing commodity tolerances that make, at most, a negligible contribution to the cumulative risk from OP pesticides. See the July 17 Federal Register notice (DOCID: fr17jy02-73). (Posted 1 Aug 02)

Announcements (15 Jan 02)

• Conference: e.hormone 2002, October 17-19, 2002, New Orleans, LA.

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