The national study, directed by University of North Carolina at Chapel Hill scientists, contrasts with earlier, less detailed work done in Northern California and published in 1998. That research suggested an association between byproducts known as trihalomethanes and loss of pregnancy.
"We think our new work should be an important contribution to policy studies," said principal investigator Dr. David A. Savitz of the UNC School of Public Health. "While it is not the final answer, what we found is largely reassuring relative to what had come before.
"The vast majority of the U.S. population is living with these exposures to drinking water byproducts," Savitz said. "If they clearly increased women's miscarriage rates, that would be a very big, very expensive problem to solve. Reducing exposure would be quite expensive for the water utilities and ultimately their customers."
The methods used in the new work make it the most ambitious and sophisticated study ever done on this issue, he said.
Savitz, Cary C. Boshamer distinguished professor and chair of epidemiology, and colleagues released a report on the investigation today (July 29). The American Water Works Association Research Foundation, a non-partisan, non-profit research group, sponsored it.
Others involved include Dr. Philip C. Singer, professor of environmental sciences and engineering and co-principal investigator, and Drs. Katherine E. Hartmann of obstetrics and gynecology and epidemiology, Amy H. Herring of biostatistics and Howard S. Weinberg of environmental sciences and engineering.