Monday, October 24, 2005

Particles and Adverse Effects on Reproductive Health

Environmental Tobacco Smoke exposure compared to no ETS presents one of the few opportunities to measure human ultrafine and fine particle effects in the 50 ug/M3 range. Non-smoking, non ETS subjects are the lowest risk group, and so easiest to demonstrate an effect of whatever extra exposure. Otherwise, there's no strong reasons for piling on to tobacco and ETS.

Full text available on-line.

BrooklynDodger reminds readers that tobacco smoke is carcinogenic in bioassay only at extreme high levels of 200 milligrams/M3 in the rat, and not carcinogenic in the mouse and hamster. Among environmental particles, tobacco smoke is way less potent than competitors.

The importance of this report would be to identify an animal model to mimic this measured human effect, then use the animal model to evaluate a variety of particle exposures.

Environ Health Perspect 113:412-417 (2005). doi:10.1289/ehp.7436 available via [Online 14 January 2005]

Effect of Environmental Tobacco Smoke on Levels of Urinary Hormone Markers

Changzhong Chen,1 Xiaobin Wang,2 Lihua Wang,3 Fan Yang,4 Genfu Tang,4 Houxun Xing,4 Louise Ryan,5 Bill Lasley,6 James W. Overstreet,6 Joseph B. Stanford,7 and Xiping Xu1

1Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA; 2Department of Pediatrics, Northwestern University Feinberg School of Medicine and Children’s Memorial Hospital and Children’s Memorial Research Center, Chicago, Illinois, USA; 3Center for Ecogenetics and Reproductive Health, Beijing Medical University, Beijing, China; 4Institute for Biomedicine, Anhui Medical University, Anhui, China; 5Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts, USA; 6Institute of Toxicology and Environmental Health and Department of Obstetrics and Gynecology, School of Medicine, University of California, Davis, California, USA; 7Health Research Center, Department of Family and Preventive Medicine, University of Utah, Salt Lake City, Utah, USA

...Our recent study showed a dose-response relationship between environmental tobacco smoke (ETS) and the risk of early pregnancy loss. Smoking is known to affect female reproductive hormones. We explored whether ETS affects reproductive hormone profiles as characterized by urinary pregnanediol-3-glucuronide (PdG) and estrone conjugate (E1C) levels. We prospectively studied 371 healthy newly married nonsmoking women in China who intended to conceive and had stopped contraception. ... In nonconception cycles, cycles with ETS exposure had significantly lower urinary E1C levels ... compared with the cycles without ETS exposure. ... In conclusion, ETS exposure was associated with significantly lower urinary E1C levels among nonconception cycles, suggesting that the adverse reproductive effect of ETS may act partly through its antiestrogen effects. ...

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