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.

Evaluation of dietary arsenic exposure and its biomarkers: a case study of West Bengal, India.

Few reports are available that characterize daily arsenic exposure through water and diet among people living in groundwater-contaminated regions and correlate it with biomarkers. The present study describes the total individual arsenic exposure and arsenic level in urine and hair of such an arsenic-exposed population in West Bengal. Demographic characteristics and the total daily arsenic intake through water and diet were determined in 167 (Group-1 participants selected from arsenic endemic region) and 69 (Group-2 participants selected from arsenic non-endemic region) in West Bengal. Out of 167 Group-1 participants 78 (Group-1A) had arsenical skin lesions while 89 Group-1B) had no such lesion. Arsenic level in water samples as well as diet, urine and hair samples, collected from all the individual participants, were estimated. The mean value of estimated total arsenic content from water and diet was 349 (range: 20-1615) µg/day in 167 (Group-1) participants living in As endemic region [As in water: mean value 54 (range:BDL-326) µg/L] and 36 (range:12-120) µg/day in 69 (Group-2) participants living in As non-endemic region (As in water: below detection level (BDL), < 0.3 µg/L). Estimated mean arsenic level in urine in these two groups of participants was 116 (range: 6-526) µg/L and 17 (range: BDL-37) µg/L and in hair was 1.0 (range: 0.22-3.98) mg/Kg and 0.16 (range: 0.06-0.37) mg/Kg, respectively. Multiple regressions analysis in Group-1 participants showed that total arsenic intake was associated significantly with urinary and hair arsenic level. The estimated regression coefficient was 0.0022 (95% confidence interval, C.I: 0.0016, 0.0028; P < 0.001) and 0.0024 (95% C.I: 0.0021, 0.003; P < 0.001), respectively. In sub group analysis, higher median urinary arsenic value relative to arsenic intake through water and diet was observed in 78 Group-1A subjects with skin lesion compared to urinary arsenic value in 89 Group-1B subjects without skin lesions, though there was a marginal difference of median total arsenic intake in these two groups. This study showed that significant elevation of arsenic level in urine and hair was associated with elevated arsenic intake through water and diet in people living in arsenic endemic region (Group-1), while these values were low in people living in non-endemic region (Group-2). Those with skin lesions were found to have higher arsenic in urine and hair compared to those without skin lesion with similar arsenic intake through water and diet.

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.

Inhibition of the emergence of multi drug resistant Staphylococcus aureus by Withania somnifera root extracts.

OBJECTIVE: To search systematically for an alternative therapy with compounds particularly from plant origin. METHODS: Efficacy test of different root extracts of Withania somnifera (W. somnifera) (L) Dunal against multi drug resistant (MDR) Staphylococcus aureus (S. aureus) variants was performed following the agar well diffusion method. Evaluation of susceptibility pattern of the isolates was carried out by employing disk diffusion method using standard antibiotic disks. RESULTS: In vitro study with W. somnifera root extracts was found to be effective against all the MDR S. aureus strains isolated from local and patient sources. Different root extracts of WS showed different degree of effectiveness against the isolates. CONCLUSIONS: The major active principles responsible for the antibacterial efficacy were mainly present in methanol (MeOH)extract and ethanol (EtOH) extracts as well as in butanol (BuOH) extract fraction. Amongst all the extracts the BuOH fraction was found to be most active against all the isolates but aqueous extract was the least active one. Finally it may be concluded that the antimicrobials from W. somnifera may raise an alternative therapy for MDR staphylococcal infections in near future.