Intervention Trial to Assess Arsenic Exposure from Food Crops in Bangladesh

The authors assessed the contribution of food irrigated with arsenic-contaminated water to human exposure to arsenic in Bangladesh. An intervention trial was conducted in a village in the Jessore District of Bangladesh, where irrigation water had been field-tested in March 2000 and was found to contain arsenic with concentrations ranging from 100 to 500 mu g/l. In May 2000, a random sample of 63 households was selected from the village, and I eligible person from each household was recruited to the study and randomized to an intervention or control group. The intervention group received food purchased from a village where irrigation water was found to contain 100 mu g/l arsenic. Pre- and postintervention urine samples were collected for urinary arsenic speciation assays. Preintervention, the mean urinary total arsenic concentrations were 139.25 mu g/l and 129.15 mu g/l for the intervention and control groups, respectively. These concentrations did not change significantly following intervention. Arsenic concentrations in samples of selected raw and cooked foods from the low-contamination area did not contain less arsenic than samples from the high-contamination area. Further studies to investigate the arsenic content of food grown in areas with high and low arsenic contamination of irrigation water are recommended.

Urinary arsenic, porphyrins and malondialdehyde in a population 16 years after arsenic mitigation program in Xinjian, China

Arsenic contamination of groundwater (0.05 to 0.84 mg/L) in Kuitun, Xinjiang was first found in 1970’s. Alternative clean surface water was introduced in 1985. We aimed to assess the exposure and heath outcome since the mitigation. In 2000, we collected a total of 360 urine samples from villagers from the endemic area and a nearby control area for arsenic (As), porphyrins and malondialdehyde (MDA) measurements. The averaged urinary As level of villagers from the endemic site (117±8.3 μg/g creatinine; 4.2 to 943.8 μg/g creat) was higher than that of the control site (73.6±3.2 μg/g creat). No significant differences were found in urinary porphyrins or MDA between the endemic and control sites. However, when the urinary arsenic was higher than 150 μg/g creat, these two biomarkers were higher in the exposed group than the control. Within the exposed group, villagers with arsenic-related skin symptoms had higher arsenic, uroporphyrin and MDA compared to those who had not shown symptoms. Sine the water mitigation, villagers whose urinary arsenic levels were 270 μg/g creat dropped from 20% to 10% of the population. Population with arsenic-related skin symptoms remained unchanged at 31%. We noted that 7.8% of those who had skin lesions were born after the implementation of intervention and that some villagers still prefer to drink the groundwater. Further, in the dry season, lack of surface water and electrical power breakdowns are to blame for failure to ensure continuous supply of clean water. It is concluded that despite the prompt action and successful water mitigation program to curb arsenic poisonings, it is essential to continue to monitor the health outcome of this population.