You are here:
ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES
Citation:
Mumford, J. L., P Mendola, Z. Ning, AND Z. Liu. ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES. Presented at American College of Epidemiology, Albuquerque, New Mexico, September 22-24, 2002.
Description:
ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES
Richard Kwok1, Pauline Mendola1 Zhixiong Ning2, Zhiyi Liu2 and Judy Mumford1
1) Epidemiology and Biomarkers Branch, Human Studies Division, NHEERL, US EPA, RTP,NC 27711.
2) Institute of Endemic Disease for Prevention and Treatment, Inner Mongolia, China.
In the Ba Men region of Inner Mongolia, China, a high prevalence of chronic arsenism has been reported in earlier studies. A survey of the water supply system was conducted between 1991-1998 to better characterize the arsenic (As) concentrations in the drinking water supply of local villages. A total of 14,866 wells were analyzed for their As content. Colorimetry based on silver diethyldithiocarbamate, an adaptation of the mercury bromide stain technique, and atomic absorption spectroscopy were used to determine the As content of the water supply. As concentrations ranged from below the limit of detection to 1.2 mg/l. Elevated concentrations were related to well depth (maximum at the 15 to 25 meter (m) category), well type (most high concentrations associated with the small household pump wells) and the date the well was built (peaks from 1980-1990). Over 43,600 persons consumed water with As concentrations above 0.01 mg/l (14,500 above 0.05 mg/l, 480 above 0.5 mg/l). There were significant differences between different counties and villages within each county. Methods used to assign individual level exposure information based on aggregate exposure data, their advantages and disadvantages will be discussed. The presented database of As in wells of the Ba Men region provides a useful tool for planning future water explorations when combined with geological information. It also helps in the design of upcoming epidemiological studies on the effects of arsenic in drinking water.
Key words:
China, Inner Mongolia, arsenic, drinking water, exposure estimation.
Corresponding author:
Richard Kwok
Epidemiology and Biomarkers Branch, Human Studies Division
U.S. EPA, NHEERL, MD 58C
Research Triangle Park, NC 27711, USA
e-mail: Kwok.Richard@epa.gov