Arabinda Das

Nutritional deficiency and arsenical manifestations: a perspective study in an arsenic-endemic region of West Bengal, India.

OBJECTIVE To assess whether nutritional deficiency increases susceptibility to arsenic-related health effects. DESIGN Assessment of nutrition was based on a 24 h recall method of all dietary constituents. SETTING Epidemiological cross-sectional study was conducted in an arsenic endemic area of West Bengal with groundwater arsenic contamination. SUBJECTS The study was composed of two groups – Group 1 (cases, n 108) exhibiting skin lesions and Group 2 (exposed controls, n 100) not exhibiting skin lesions – age- and sex-matched and having similar arsenic exposure through drinking water and arsenic levels in urine and hair. RESULTS Both groups belonged to low socio-economic strata (Group 1 significantly poorer, P<0·01) and had low BMI (prevalence of BMI<18·5 kg/m2: in 38% in Group 1 and 27% in Group 2). Energy intake was below the Recommended Daily Allowance (set by the Indian Council of Medical Research) in males and females in both groups. Increased risk of arsenical skin lesions was found for those in the lowest quintile of protein intake (v. highest quintile: OR=4·60, 95% CI 1·36, 15·50 in males; OR=5·62, 95% CI 1·19, 34·57 in females). Significantly lower intakes of energy, protein, thiamin, niacin, Mg, Zn and choline were observed in both males and females of Group 1 compared with Group 2. Significantly lower intakes of carbohydrate, riboflavin, niacin and Cu were also observed in female cases with skin lesions compared with non-cases. CONCLUSIONS Deficiencies of Zn, Mg and Cu, in addition to protein, B vitamins and choline, are found to be associated with arsenical skin lesions in West Bengal.

Hypertension in chronic arsenic exposure: A case control study in West Bengal.

Various systemic manifestations are reported to be caused by chronic arsenic exposure in the population living in the Indo-Bangladesh subcontinent. This study from West Bengal assesses the likelihood of occurrence of hypertension (HTN) in individuals resident in an area of high groundwater contamination with arsenic (Nadia district) compared to those from a non-contaminated area (Hoogly district) in West Bengal, India. Two hundred and eight study participants (Group 1) were recruited from a cross-sectional study in six villages in the Nadia district and 100 controls (Group 2) from a village in the Hoogly district. The two groups were evenly matched in regard to age and sex. History taking and clinical examination including blood pressure measurement were undertaken in each participant. Water samples from current and previous drinking water sources and hair and urine samples from each participant were collected for estimation of arsenic. The present study shows evidence of increased association of HTN in individuals resident in arsenic endemic region compared to those from a non-endemic region in West Bengal. There were increased odds ratios for HTN [Adjusted Odds Ratio, OR, 2.87 (95 %CI = 1.26–4.83)] in Group- 1 participants compared to Group- 2 people. Within Group 1, there was no difference in prevalence of HTN between those with and without skin lesion. There was a dose-effect relationship seen with increasing cumulative arsenic exposure and arsenic level in hair and HTN in participants living in arsenic endemic region.The findings reported here support an association between arsenic exposure and HTN. More work is needed to characterize the link further.

Dietary arsenic exposure with low level of arsenic in drinking water and biomarker: A study in West Bengal

The authors investigated association of arsenic intake through water and diet and arsenic level in urine in people living in arsenic endemic region in West Bengal supplied with arsenic-safe water (<50 μg L−1). Out of 94 (Group-1A) study participants using water with arsenic level <50 μg L−1, 72 participants (Group-1B) were taking water with arsenic level <10 μg L−1. Multiple regressions analysis conducted on the Group-1A participants showed that daily arsenic dose from water and diet were found to be significantly positively associated with urinary arsenic level. However, daily arsenic dose from diet was found to be significantly positively associated with urinary arsenic level in Group-1B participants only, but no significant association was found with arsenic dose from water in this group. In a separate analysis, out of 68 participants with arsenic exposure through diet only, urinary arsenic concentration was found to correlate positively (r = 0.573) with dietary arsenic in 45 participants with skin lesion while this correlation was insignificant (r = 0.007) in 23 participants without skin lesion. Our study suggested that dietary arsenic intake was a potential pathway of arsenic exposure even where arsenic intake through water was reduced significantly in arsenic endemic region in West Bengal. Observation of variation in urinary arsenic excretion in arsenic-exposed subjects with and without skin lesion needed further study.

Chronic lung disease and detection of pulmonary artery dilatation in high resolution computerized tomography of chest in chronic arsenic exposure

Lung affection in chronic arsenicosis developing from chronic ingestion of arsenic contaminated groundwater has been known but little is known on its effect on pulmonary arterial system. A cross sectional study was carried out at two geographically similar areas and demographically similar populations with or without evidence of chronic arsenic exposure in West Bengal, India. The willing participants in both the groups with chronic respiratory symptoms were evaluated with High Resolution Computerized Tomography (HRCT) of Chest. Evaluation of High Resolution Computerized Tomography of chest followed clinical assessment of lung disease in194 and 196 subjects from the arsenic exposed and unexposed people; the former had a higher prevalence of cough OR(Odds Ratio) 3.23 (95% CI(Confidence Interval): 1.72–6.07) and shortness of breath OR1.76 (95% CI: 0.84–3.71), respectively. The arsenic exposed individuals showed higher score for bronchiectasis [mean ± SD(Standard Deviation)] as 2.41 ± 2.32 vs. 1.22 ± 1.48 (P <0.001), pulmonary artery branch dilatation (PAD) as 2.48 ± 2.33 vs. 0.78 ± 1.56, (P <0.001) and pulmonary trunk dilatation as 0.26 ± 0.45 vs. nil. Age-adjusted prevalence odds ratio (POR) for Pulmonary Artery Dilatation Found in HRCT comparing those exposed to arsenic (Group 1) to unexposed participants (Group 2) was found to be 6.98 (CI: 2.26–16.48). There was a strong dose–response relationship between the PAD (Pulmonary Artery Dilatation) and cumulative arsenic exposure. Pulmonary trunk and branch dilatation in chronic arsenicosis is a frequent abnormality seen in HRCT Chest of arsenicosis patients. The significance of such finding needs further investigation.

Epidemiology of Diarrhea among under-five Children in a Village in Sunderbans, South 24 Parganas, West Bengal, India

Background: Though various studies have been carried out on the problem of diarrheal disease in under-five children in various parts of India, no comprehensive study has so far been done on this problem in deltaic region of West Bengal, the Sunderbans. Objectives: A study was undertaken in a prototype village, in Sunderban area to assess the prevalence of diarrheal disease in under-five children and to assess various factors which influence its occurrence. Methods: Information was collected from all households from village Hogolduri, in Sunderban area, South 24 Parganas regarding socioeconomic characteristics, water source, and sanitation status of the population. Frequency of occurrence of Diarrhea during last three months in each child under-five years of age was recorded and maternal characteristics and child’s nutrition were also noted. Results: Among the 5264 people residing in 1231 households in Hogolduri village, majority of the people were Muslims (79%). Majority (80.7%) of the families belonged to below-poverty-line (BPL). Out of 486 children living in the village, from which all the data were available, diarrhea occurred during last three months in 45.68% of children. Important contributing factors for such morbidity of children were found to be absence of toilets in households, non-use of soap for hand washing after defecation and after child’s stool cleaning by mothers, absence of vaccination against measles and low nutritional status of children. Conclusions: Multiple factors are responsible for high incidence of diarrheal disease in children in a prototype village in Sunderban area .

Estimation of Urinary Arsenic Exposure using Copula-Based Regression: A Case Study of West Bengal

Copula functions are useful in constructing multivariate distributions using various marginal distributions and non-linear dependence structures. This paper uses copula functions to construct multivariate distributions with one-sided marginal distributions and copula-based regression to estimate the arsenic exposure in urine using arsenic intake through water and diet as potential covariates in a study in West Bengal, India. As arsenic concentration in urine, water, and diet takes only positive values and negative amount of arsenic concentration in urine, water, and diet are impossibility, one-sided distribution with positive real line support is assumed for these characteristics. Gaussian and Farlie-Gumbel-Morgenstern (FGM) families of copula are considered to capture the non-linear association among these variables. The maximum likelihood method is applied to estimate the parameters of the models. The estimation result suggests that the covariates significantly affect the urinary arsenic exposure, and arsenic intake through diet was a potential contributor of urinary arsenic exposure even when arsenic intake through water was reduced significantly in this arsenic-affected region of West Bengal.