Elevated arsenic in Mexico's drinking water poses health risks for pregnant women, infants

October 27, 2014

Millions of people around the world drink water with levels of inorganic arsenic that exceed standards set by the World Health Organization. A new Gillings School of Global Public Health study highlights that certain populations, including pregnant women and newborn children, are especially vulnerable when exposed to increased levels of arsenic.

Dr. Rebecca Fry

In an article published online Oct. 17 by Environmental Health Perspectives, Rebecca Fry, PhD, associate professor of environmental sciences and engineering at the Gillings School, and colleagues found that arsenic, a metalloid naturally occurring in water and used in pesticides and to strengthen some metals, is associated with impaired fetal growth.

Other Gillings School co-authors are Jessica E. Laine, epidemiology doctoral student; Katherine A. Bailey, PhD, postdoctoral fellow, and Lisa Smeester, MS, researcher, both in the environmental sciences and engineering department; Andrew F. Olshan, PhD, Barbara Sorenson Hulka Distinguished Professor in Cancer Epidemiology and epidemiology department chair; and nutrition faculty members Zuzana Drobna, PhD, research assistant professor, and Miroslav Styblo, PhD, professor.

Long-term exposure to arsenic, which also is used in semiconductors and wood products, has been linked to skin lesions, cardiovascular and vascular disease, cancer and diabetes. Fry’s study looked at a cohort of 200 pregnant women in Gomez Palacio, Mexico, measuring levels of inorganic arsenic and comparing those measurements with birth outcomes.

The outcomes were analyzed for their relationship to arsenic in drinking water and its presence in the mothers’ urine. More than half of the women in the study had levels that exceeded maximum levels recommended by the World Health Organization (WHO) and Environmental Protection Agency, and those levels were associated with lower newborn birth weight and gestational age as well as lower gestational age and newborn length.

More than half of drinking water samples taken in Gomez Palacio exceeded WHO guidelines for arsenic content, indicating that women drinking municipal water are at risk for elevated exposure to arsenic. Pregnant women with elevated arsenic levels were linked to lower gestational age and newborn length. The findings also raise concerns about the potential later life health effects in the children of the study.

The study’s results underscore the risks associated with arsenic exposure in vulnerable populations and highlight the need for a long-term study to examine the effects of environmental exposure to arsenic on the health of women and children and to provide information to protect individuals from preventable exposure.

Other authors are Drs. Marisela Rubio-Andrade and Gonzalo G. Garcia-Vargas, of the facultad de medicina at the Universidad Juarez del Estado de Durango, in Gómez  Palacio, Durango, Mexico.