West Bengal || Bangladesh
Middle Ganga Plain, Bihar ||
Iron Concentration in Tube Well Water
Samples from 225 tube wells were analyzed for iron from Semria Ojha Patti and the surrounding 5 villages. The result (mean 2482 µg/L, minimum 145 µg/L, and maximum 8624 µ g/L) shows the iron concentrations to be higher than previously reported (0–700 µg/L) for the Middle Plain (Acharya et al. 1999). The correlation between concentrations of iron and arsenic in water is poor (r=0.478).
Arsenical Skin Lesions. In this preliminary survey of 550 self-selected volunteers from the total 5000 villagers, 60 individuals (10.9% of the total and 6.3% of children) with arsenical skin lesions were registered. Figure 3 shows one subject with the full range of arsenical skin lesions including hyperkeratosis, Bowen’s (suspected), and nonhealing ulcer (suspected cancer). The skin lesions observed in the village were similar to those noted in West Bengal and Bangladesh, but the relative prevalence of each type cannot be compared because of the inherent bias in self-selected volunteers with women particularly reluctant to be examined. Figure 4 tabulates the type of skin involvement of adults and children, the latter an unusual finding compared to West Bengal and Bangladesh (Biswas et al. 1998; Chowdhury et al. 1999, 2000b; Rahman et al. 2001; Roy Chowdhury et al. 1997).?Inorganic Arsenic and Its Metabolites in Urine. Analyses of 51 urine samples, including the mean, median, minimum, and maximum are given in Figure 5, along with a plot of the significant correlation of urine arsenic with drinking water arsenic (r=0.774; p<0.05). Of the 51 urine samples analyzed, 98% have arsenic concentrations above the normal excretion level of arsenic in urine (Farmer and Johnson 1990), with 47% >500 µg/L, 33.3% > 1000 µg/L, and 5.9% >3000 µg/L. The comparison of the urine arsenic of Semria Ojha Patti village with that of two highly arsenic contaminated villages described in our earlier work (Chowdhury et al. 2001) and cited in Table 1 shows a higher burden for Semria Ojha Patti village, Bihar: n=51, mean 798 µg/L, median 387 µg/L, range 24–3696 µg/L, than for Fakirpara village, West Bengal: n=325, mean 528 µg/L, median 318 µg/L, range 7–2911µ g/L, or Samta village, Bangladesh: n=300, mean 538 µg/L, median 289 µg/L, range 24– 3085 µg/L). The urine arsenic of control populations (Chowdhury et al. 2003) with drinking water arsenic <3 µg/L was low in West Bengal (n=75, mean 16, median 15, range 10–41) and Bangladesh (n=62, mean 31, range 6–94, median 29). Village adults drink an estimated 4 liters of water per day and children 2 liters. Contaminated water is utilized for food preparation. In West Bengal, we attributed (Chowdhury et al. 2001) about 20–30% of the arsenic body burden to rice and vegetables grown in paddies irrigated by contaminated water; agricultural practices appeared similar in this village. Total Arsenic in Hair and Nails. A total of 59 hair samples (34 samples from those with arsenical skin lesions and 25 without) and 38 nail samples (23 samples from those with arsenical skin lesions and 15 without) were analyzed for total arsenic. We found 57.6% of hair samples and 76.3% of nail samples to be above the normal range with a similar correlation of drinking water arsenic with the concentration in the hair (r=0.733; p<0.05; Figure 6) and the nails (r=0.719; p<0.05; Figure 7), similar to the findings in our West Bengal and Bangladesh studies (Biswas et al. 1998; Mandal 1998).?Arsenic Affected Children (6–11 years). In our field studies over the last 15 years in West Bengal and 7 years in Bangladesh, we have observed skin manifestations in exposed children under 11 years of age only under conditions of extreme exposure coupled with malnutrition (Chowdhury et al. 2000b; Rahman et al. 2001). In the southern area of Semria Ojha Patti we identified a group of children (n=8) with skin involvement. All were drinking water from the same tube well, arsenic concentration 749 µg/L. Table 2 lists their dermatological features and the concentrations of arsenic in their urine (inorganic arsenic and its metabolites), hair, and nails. The biological samples from village children with skin lesions are compared with those of children with arsenical skin lesions from the reference villages cited in Table 1. It is found that the Semria Ojha Patti village children have higher concentrations of arsenic in their biological samples compared to the Samta village, Bangladesh (Biswas et al. 1998) and Fakirpara village, West Bengal (Mandal et al. 1998). The arsenic concentrations at all 3 sites exceed those of control populations reported in our earlier work (Chowdhury et al. 2003).