Chlorination May Increase Stillbirth Risk

Chlorination May Increase Stillbirth Risk

Publish Date: 4/5/2004 1:11:00 PM
Source: SkinCareIndia Correspondent
 
Exposure to tap water containing high levels of chlorination byproducts, 
particularly compounds called trihalomethanes (THMs), is associated with an 
increased risk of stillbirth, Canadian researchers report. 

Still, whether THMs cause stillbirth is unclear, because the risk did not 
increase in step with increasing levels of the chemicals. 

On the other hand, the new findings support several reports that have linked THM 
exposure with stillbirth, including a study by the same research group published 
in 1999. 

Dr. Linda Dodds, from Dalhousie University in Halifax, Nova Scotia, and 
colleagues interviewed 112 women who had a stillbirth and 398 "controls" who had 
a live birth, and analyzed water samples obtained from the women's homes. 

The investigators' findings are published in the March issue of Epidemiology. 

Women with tap water containing THM levels of at least 80 micrograms per liter 
were 2.2-times more likely to have a stillbirth than women not exposed to THM. 
The increased risk with THM exposure held true for both asphyxia-related 
stillbirths and, to a less extent, unexplained stillbirths. 

However, women in the middle range of THM exposure had the second highest risk 
of stillbirth - a "non-linear" relationship, which brings causality into question. 

If the link between THM exposure and stillbirth is causal, "consuming filtered 
or bottled water will not completely eliminate risk because showering and 
bathing contributed to the overall exposure," the authors point out. 

They also suggest that "a decrease in population exposure will be most 
effectively achieved at treatment plants rather than the household level."