Safe limit of arsenic in soil in relation to dietary exposure of arsenicosis patients from Malda district, West Bengal- A case study.

Safe limit of arsenic in soil in relation to dietary exposure of arsenicosis patients was established in Malda district of West Bengal. Out of 182 participants examined, 80 (43.9%) participants showed clinical features of arsenicosis, characterized by arsenical skin lesion (pigmentation and keratosis), while 102 participants did not have any such lesion (control). Experimental results of the twenty eight soils (own field) of the participants showed the mean Olsen extractable and total arsenic concentration of 0.206 and 6.70mgkg-1, respectively. Arsenic concentration in rice grain ranged from 2.00 to 1260µgkg-1 with the mean value of 146µgkg-1. The hazard quotient (HQ) for intake of As by human through consumption of rice varied from 0.03 to 3.52. HQ exceeds 1.0 for drinking water and rice grain grown in the study area in many cases. As high as 77.6% variation in As content in rice grain could be explained by the solubility-free ion activity model. Toxic limit of extractable As in soil for rice in relation to soil properties and human health hazard, associated with consumption of rice grain by human, was established. For example, the permissible limit of Olsen extractable As in soil would be 0.43mgkg-1 for rice cultivation, if soil pH and organic carbon content were 7.5% and 0.50%, respectively. However, the critical limit of Olsen extractable As in soil would be 0.54mgkg-1, if soil pH and organic carbon were 8.5% and 0.75%, respectively. The conceptual framework of fixing the toxic limit of arsenic in soils with respect to soil properties and human health under modeling-framework was established.

Skin score correlates with global DNA methylation and GSTO1 A140D polymorphism in arsenic-affected population of Eastern India.

Arsenic is a potent environmental toxicant causing serious public health concerns in India, Bangladesh and other parts of the world. Gene- and promoter-specific hypermethylation has been reported in different arsenic-exposed cell lines, whereas whole genome DNA methylation study suggested genomic hypo- and hypermethylation after arsenic exposure in in vitro and in vivo studies. Along with other characteristic biomarkers, arsenic toxicity leads to typical skin lesions. The present study demonstrates significant correlation between severities of skin manifestations with their whole genome DNA methylation status as well as with a particular polymorphism (Ala 140 Asp) status in arsenic metabolizing enzyme Glutathione S-transferase Omega-1 (GSTO1) in arsenic-exposed population of the district of Nadia, West Bengal, India.

Baseline characteristics of HIV & hepatitis B virus (HIV/HBV) co-infected patients from Kolkata, India.

BACKGROUND & OBJECTIVES: Hepatitis B virus (HBV) and HIV co-infection has variable prevalence worldwide. In comparison to HBV mono-infection, the course of chronic HBV infection is accelerated in HIV/HBV co-infected patients. the present study was carried out to analyse the baseline characteristics (clinical, biochemical, serological and virological) of treatment naïve HIV/HBV co-infected and HIV mono-infected patients. METHODS: Between July 2011 and January 2013, a total number of 1331 HIV-seropositive treatment naïve individuals, enrolled in the ART Centre of Calcutta School of Tropical Medicine, Kolkata, India, were screened for hepatitis B surface antigen (HBsAg). A total of 1253 HIV mono-infected and 78 HIV/HBV co-infected patients were characterized. The co-infected patients were evaluated for HBeAg and anti-HBe antibody by ELISA. HIV RNA was quantified for all co-infected patients. HBV DNA was detected and quantified by real time-PCR amplification followed by HBV genotype determination. RESULTS: HIV/HBV co-infected patients had proportionately more advanced HIV disease (WHO clinical stage 3 and 4) than HIV mono-infected individuals (37.1 vs. 19.9%). The co-infected patients had significantly higher serum bilirubin, alanine aminotransferase (ALT), alkaline phosphatase and ALT/platelet ratio index (APRI). CD4 count was non-significantly lower in co-infected patients. Majority (61.5%) were HBeAg positive with higher HIV RNA (P<0.05), HBV DNA (p<0.001) and APRI (p<0.05) compared to those who were HBeAg negative. HBV/D was the predominant genotype (73.2%) and D2 (43.7%) was the commonest subgenotype. INTERPRETATION & CONCLUSIONS: HIV/HBV co-infected patients had significantly higher serum bilirubin, ALT, alkaline phosphatase and lower platelet count. HBeAg positive co-infected patients had higher HIV RNA and HBV DNA compared to HBeAg negative co-infected patients. Prior to initiation of antiretroviral treatment (ART) all patients should be screened for HBsAg to initiate appropriate ART regimen.

Effect of drinking arsenic-contaminated water in children.

Chronic arsenic toxicity due to drinking of arsenic-contaminated water has been a major environmental health hazard throughout the world including India. Although a lot of information is available on health effects due to chronic arsenic toxicity in adults, knowledge of such effect on children is scanty. A review of the available literature has been made to highlight the problem in children. Scientific publications on health effects of chronic arsenic toxicity in children with special reference to psychological issues are reviewed. The prevalence of skin abnormalities such as pigmentation change and keratosis, the diagnostic signs of chronic arsenic toxicity, vary in various arsenic-exposed children population in different regions of the world. The occurrence of chronic lung disease including pulmonary interstitial fibrosis has been described in arsenic-exposed children in Chile. Affection of intellectual function has also been reported to occur in arsenic-exposed children studied in Thailand, Bangladesh, and India. Methylation patterns of arsenic in children aggregate in families and are correlated in siblings, providing evidence of a genetic basis for the variation in arsenic methylation. Chronic arsenic toxicity due to drinking of arsenic-contaminated water causes significant morbidity in children resulting in skin lesions, lung disease, and defect in intellectual function.

Systemic manifestations in chronic arsenic toxicity in absence of skin lesions in West Bengal.

BACKGROUND & OBJECTIVE: Pigmentation and keratosis are the prerequisites to diagnose arsenicosis. However, many systemic manifestations occur in association with pigmentation and keratosis in people exposed to chronic drinking of arsenic contaminated water. The present study aim to find out whether systemic manifestations occur in significant number of cases in arsenic exposed people in the absence of skin lesions in an affected district in West Bengal, India. METHODS: A cross-sectional study was carried out in South 24 Parganas, an arsenic affected district of West Bengal, India. Both dermatological and systemic manifestations were recorded and water samples collected for arsenic analysis from 7683 participants. A correlation of systemic manifestations in relation to arsenic exposure was carried out in subjects having no arsenical skin lesion. Prevalence odds ratio (POR) was calculated for each outcome comparing those with high arsenic exposure with those with lowest exposure. RESULTS: The frequency of occurrence of various clinical manifestations like weakness, anaemia, diarrhoea, hepatomegaly and lung disease was found to be significantly higher among participants drinking water having arsenic concentration > or = 50 microg/l in comparison to those taking water with arsenic content below this level. Further, there was increased occurrence of these manifestations with increasing concentration of arsenic level in drinking water, and this followed a dose-response relationship. INTERPRETATION & CONCLUSION: It appears that it is worthwhile to include people with systemic manifestations in absence of skin lesions with evidence of arsenic exposure as suspected cases of arsenicosis for case detection and in surveillance programme.

Chronic arsenic toxicity & human health.

Chronic arsenic toxicity (arsenicosis) due to drinking of arsenic contaminated ground water is a major environmental health hazard throughout the world including India. A lot of new information is emerging from extensive research on health effects of chronic arsenic toxicity (CAT) in humans during the last two decades. Available literature has been reviewed to highlight the problem including its malignancies. Pigmentation and keratosis are the specific skin lesions characteristics of CAT. CAT also produces various systemic manifestations over and above skin lesions, important ones being chronic lung disease like chronic bronchitis, chronic obstructive pulmonary disease and bronchiectasis, liver disease like non-cirrhotic portal fibrosis and other diseases like polyneuropathy, peripheral vascular disease, hypertension and ischeamic heart disease, diabetes mellitus, non-pitting oedema of feet/hands, weakness and anaemia. Cancer of skin, lung and urinary bladder are important cancers associated with chronic arsenic toxicity. Stoppage of drinking of arsenic contaminated water is the main stay in the management of arsenicosis as specific chelation therapy has limited value. Early skin cancer, detectable by regular active surveillance, is curable. In addition to dermatological features, CAT produces protean clinical manifestations. Treatment of arsenicosis is unsatisfactory and is mostly symtomatic.

Arsenic levels in drinking water and the prevalence of skin lesions in West Bengal, India.

BACKGROUND: A cross-sectional survey was conducted between April 1995 and March 1996 to investigate arsenic-associated skin lesions of keratosis and hyperpigmentation in West Bengal, India, and to determine their relationship to arsenic water levels. METHODS: In all, 7683 participants were examined and interviewed, and the arsenic levels in their drinking water measured. RESULTS: Although water concentrations ranged up to 3400 microg/l of arsenic, over 80% of participants were consuming water containing <500 microg/l. The age-adjusted prevalence of keratosis was strongly related to water arsenic levels, rising from zero in the lowest exposure level (<50 microg/l) to 8.3 per 100 for females drinking water containing >800 microg/l, and increasing from 0.2 per 100 in the lowest exposure category to 10.7 per 100 for males in the highest exposure level (> or =800 microg/l). However, 12 cases with keratosis (2 females and 10 males) were drinking water containing <100 microg/l of arsenic. Findings were similar for hyperpigmentation, with strong dose-response relationships. Among those with hyperpigmentation, 29 cases were exposed to drinking water containing <100 microg/l. Calculation by dose per body weight showed that men had roughly two to three times the prevalence of both keratosis and hyperpigmentation compared to women apparently ingesting the same dose of arsenic from drinking water. Subjects who were below 80% of the standard body weight for their age and sex had a 1.6 fold increase in the prevalence of keratoses, suggesting that malnutrition may play a small role in increasing susceptibility. CONCLUSION: The surprising finding of cases who had arsenic-associated skin lesions with apparently low exposure to arsenic in drinking water needs to be confirmed in studies with more detailed exposure assessment. Further research is also needed concerning susceptibility factors which might be present in the exposed population.

Histological changes in hamster liver by ES antigen of Ascaris suum.

Polyacrylamide gel electrophoresis with SDS (PAGE-SDS) of the ES antigens of A. suum revealed several protein molecules which differed from those obtained in ES antigens of A. lumbricoides. Nature of liver damage caused by ES antigens of A. suum was studied in hamsters to find out the nature of damage and to compare with those caused by ES antigens of A. lumbricoides. Feeding of ES antigens of A. suum was carried out in 7 hamsters for 75 days. After such feeding gross hepatic damage was noticed. This was characterized by pericentrivenular degeneration and necrosis of liver parenchyma, the lesions being different and much more severe than those observed in hamster challenged by ES products of A. lumbricoides. The lesions appear to be immune mediated.

Objective evaluation of psychological abnormality in irritable bowel syndrome.

BACKGROUND: Irritable bowel syndrome (IBS) is frequently regarded as a psychological disorder. Data on objective evaluation of psychological abnormalities among IBS patients and control subjects are scanty in our country. We therefore objectively studied patients with IBS. METHODS: 42 patients satisfying the Manning's criteria and Munich workers' for diagnosis of IBS underwent psychological evaluation using the following tests: a) Eyesenck personality questionnaire. b) State and trait anxiety inventory according to Speilberger's method. c) Hamilton depression rating scale for detection of depression. d) Whitely index of hypochondriasis and discriminant function by Pilowsky's illness behavior questionnaire. RESULTS: Neuroticism was detected in 76% of IBS patients compared to 9% in control population (p < 0.01). State and trait anxiety scores were 44.5 +/- 17.1 and 49.0 +/- 15.3 respectively in IBS patients; these were higher than those in controls (35.5 +/- 7.5 and 41.2 +/- 6.1 respectively; p < 0.01). Severe depression was observed in 26% of IBS patients and 6% of control subjects (p < 0.05). Significantly higher hypochondriasis score was observed in IBS patients as compared to controls (p < 0.001). CONCLUSION: Neuroticism, hypochondriasis and depression were significantly more prevalent in IBS patients attending a clinic, compared to control population.

Hepatic manifestations in chronic arsenic toxicity.

OBJECTIVE: The hepatotoxic action of arsenic, when used as a therapeutic agent, has long been recognized. Data on liver involvement following chronic exposure to arsenic-contaminated water are scanty. We report the nature and degree of liver involvement on the basis of hospital-based and cohort follow-up studies in patients who consumed arsenic-contaminated drinking water for 1 to 15 years. METHODS: 248 patients with evidence of chronic arsenic toxicity underwent clinical and laboratory examinations including liver function tests and HBsAg status. Liver biopsy was done in 69 cases; in 29 patients, liver arsenic content was estimated by neutron activation analysis. A cohort follow up of 23 patients who took arsenic-free water for 2-12 years was also carried out. RESULTS: Hepatomegaly was present in 190 of 248 patients (76.6%). Noncirrhotic portal fibrosis (91.3%) was the predominant lesion in liver histology. The maximum arsenic content in liver was 6 mg/Kg (mean 1.46 [0.42], control value 0.16 [0.04]; p < 0.001); it was undetected in 6 of 29 samples studied. Cohort follow-up studies showed elevation of globulin in four cases and development of esophageal varices in one case. CONCLUSION: We report the largest number of patients with liver disease due to chronic arsenicosis from drinking arsenic-contaminated water. Noncirrhotic portal fibrosis is the predominant lesion in this population.

Creatinine, diet, micronutrients, and arsenic methylation in West Bengal, India.

BACKGROUND: Ingested inorganic arsenic (InAs) is methylated to monomethylated (MMA) and dimethylated metabolites (DMA). Methylation may have an important role in arsenic toxicity, because the monomethylated trivalent metabolite [MMA(III)] is highly toxic. OBJECTIVES: We assessed the relationship of creatinine and nutrition--using dietary intake and blood concentrations of micronutrients--with arsenic metabolism, as reflected in the proportions of InAS, MMA, and DMA in urine, in the first study that incorporated both dietary and micronutrient data. METHODS: We studied methylation patterns and nutritional factors in 405 persons who were selected from a cross-sectional survey of 7,638 people in an arsenic-exposed population in West Bengal, India. We assessed associations of urine creatinine and nutritional factors (19 dietary intake variables and 16 blood micronutrients) with arsenic metabolites in urine. RESULTS: Urinary creatinine had the strongest relationship with overall arsenic methylation to DMA. Those with the highest urinary creatinine concentrations had 7.2% more arsenic as DMA compared with those with low creatinine (p < 0.001). Animal fat intake had the strongest relationship with MMA% (highest tertile animal fat intake had 2.3% more arsenic as MMA, p < 0.001). Low serum selenium and low folate were also associated with increased MMA%. CONCLUSIONS: Urine creatinine concentration was the strongest biological marker of arsenic methylation efficiency, and therefore should not be used to adjust for urine concentration in arsenic studies. The new finding that animal fat intake has a positive relationship with MMA% warrants further assessment in other studies. Increased MMA% was also associated, to a lesser extent, with low serum selenium and folate.

Arsenic and non-malignant lung disease.

Many aquifers in various parts of the world have been found to be contaminated with arsenic at concentration above 0.05 mg/L. However reports of large number of affected people in India and Bangladesh are unprecedented. Characteristic skin lesions (pigmentation, depigmentation and keratosis) are the hallmark signs of chronic arsenic toxicity. Emerging evidences show that ingestion of arsenic through drinking water may also lead to non-malignant respiratory effects. Early report of non-malignant pulmonary effect of chronic ingestion of arsenic was available from studies in children in Chile as early as 1970. However on the basis of case studies, respiratory effect of chronic arsenic toxicity in adults following drinking of arsenic contaminated water in West Bengal was first reported in 1997. Epidemiological studies carried out in West Bengal on a population of 7683 showed that the prevalence odds ratio (POR) estimates were markedly increased for participants with arsenic induced skin lesions who also had high levels of arsenic in their current drinking water source (> or = 0.5 mg/L) compared with individuals who had normal skin and were exposed to low levels of arsenic (< 0.05 mg/L). In participants with skin lesions, age-adjusted POR estimates for chronic cough were 7.8 for females (95% CI:3.1-19.5) and 5.0 for males (95% CI:2.6-9.9). In Bangladesh, similar study carried out on a population of 218 showed that the crude prevalence ratio for chronic bronchitis was found to be 10.3 (95% CI:2.4-43.1) for females and 1.6 (95% CI:0.8-3.1) for males. Reports of lung function tests were available from both hospital and population based studies. Results show evidences of restrictive, obstructive and combined obstructive and restrictive lung disease in different people having chronic lung disease associated with chronic arsenic toxicity. On the basis of clinical study, chest X-ray and HRCT done in Arsenicosis patients with features of chronic lung disease, the abnormalities observed were varied. Evidences of obstructive pulmonary disease (COPD), interstitial lung disease (ILD) and bronchiectasis were found in some of the cases. Results of studies carried out on people showing features of Arsenicosis due to drinking arsenic contaminated water provide evidence that arsenic is a potent respiratory toxicant, even following ingestion.

Blood concentrations of methionine, selenium, beta-carotene, and other micronutrients in a case-control study of arsenic-induced skin lesions in West Bengal, India.

Previous studies have suggested that susceptibility to arsenic toxicity could be influenced by micronutrients, in particular selenium, methionine, and beta-carotene. A case-control study was conducted in West Bengal, India, in a region known to have groundwater arsenic contamination, to determine whether differences in micronutrient status contribute to susceptibility to arsenic-induced skin lesions. Micronutrient status was assessed by blood levels of specific micronutrients and metabolic indicators. Blood was obtained from 180 cases with skin lesions and 192 controls. Blood assays measured micronutrients and carotenoids (folate, selenium, vitamin B12, vitamin B6, retinol, alpha-tocopherol, lutein/zeaxanthin, beta-carotene, lycopene, beta-cryptoxanthin) and metabolic indicators such as glucose, cholesterol, transthyretin, amino acids, and proteins potentially associated with methylation (cysteine, homocysteine, methionine, glutathione). The distributions of nutrient concentrations were similar in cases and controls. The median selenium concentrations in cases and controls were both 1.15 micromol/L, and there was little evidence of differences in other micronutrients. Odds ratios (ORs) for arsenic-induced skin lesions were estimated for each quartile of nutrient concentrations, using the quartile with the highest nutrient level as the referent group. There were no clear trends associated with deficiencies of any micronutrient or metabolic indicator. For decreasing quartiles of selenium, the OR estimates were 1.00, 0.67, 0.99, 0.80; P=0.81; for methionine, the OR estimates were 1.00, 0.83, 0.78, 0.72; P=0.29. For beta-carotene, the ORs were 1.00, 0.53, 0.51, 0.96, demonstrating no increased risk at the lower quartiles. The measured micronutrients and metabolic indicators investigated do not appear to modify the risk of developing arsenic-induced skin lesions. The lack of any trend of increasing risk with lower selenium, vitamin E, and beta-carotene concentrations has important implications for proposed therapeutic interventions. The emphasis of interventions should be on reducing arsenic exposure.

Pregnancy outcomes, infant mortality, and arsenic in drinking water in West Bengal, India.

Between 2001 and 2003, the authors studied pregnancy outcomes and infant mortality among 202 married women in West Bengal, India. Reproductive histories were ascertained using structured interviews. Arsenic exposure during each pregnancy, including all water sources used, was assessed; this involved measurements from 409 wells. Odds ratios for spontaneous abortion, stillbirth, neonatal mortality, and infant mortality were estimated with logistic regression based on the method of generalized estimating equations. Exposure to high concentrations of arsenic (> or =200 microg/liter) during pregnancy was associated with a sixfold increased risk of stillbirth after adjustment for potential confounders (odds ratio (OR) = 6.07, 95% confidence interval (CI): 1.54, 24.0; p = 0.01). Arsenic-related skin lesions were found in 12 women who had a substantially increased risk of stillbirth (OR = 13.1, 95% CI: 3.17, 54.0; p = 0.002). The odds ratio for neonatal death was 2.81 (95% CI: 0.73, 10.8). No association was found between arsenic exposure and spontaneous abortion (OR = 1.01, 95% CI: 0.38, 2.70) or overall infant mortality (OR = 1.33, 95% CI: 0.43, 4.04). This study adds to the limited evidence that exposure to high concentrations of arsenic during pregnancy increases the risk of stillbirth. However, there was no indication of the increased rates of spontaneous abortion and overall infant mortality that have been reported in some studies.

Implications of oxidative stress and hepatic cytokine (TNF-alpha and IL-6) response in the pathogenesis of hepatic collagenesis in chronic arsenic toxicity.

INTRODUCTION: Noncirrhotic portal fibrosis has been reported to occur in humans due to prolonged intake of arsenic contaminated water. Further, oxystress and hepatic fibrosis have been demonstrated by us in chronic arsenic induced hepatic damage in murine model. Cytokines like tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) are suspected to play a role in hepatic collagenesis. The present study has been carried out to find out whether increased oxystress and cytokine response are associated with increased accumulation of collagen in the liver due to prolonged arsenic exposure and these follow a dose-response relationship. METHODS: Male BALB/c mice were given orally 200 microl of water containing arsenic in a dose of 50, 100, and 150 mug/mouse/day for 6 days a week (experimental group) or arsenic-free water (<0.01 microg/l, control group) for 3, 6, 9 and 12 months. Hepatic glutathione (GSH), protein sulfhydryl (PSH), glutathione peroxidase (GPx), Catalase, lipid peroxidation (LPx), protein carbonyl (PC), interleukin (IL-6), tumor necrosis factor (TNF-alpha), arsenic and collagen content in the liver were estimated from sacrificed animals. RESULTS: Significant increase of lipid peroxidation and protein oxidation in the liver associated with depletion of hepatic thiols (GSH, PSH), and antioxidant enzymes (GPx, Catalase) occurred in mice due to prolonged arsenic exposure in a dose-dependent manner. Significant elevation of hepatic collagen occurred at 9 and 12 months in all the groups associated with significant elevation of TNF-alpha and IL-6. However, arsenic level in the liver increased progressively from 3 months onwards. There was a positive correlation between the hepatic arsenic level and collagen content (r = 0.8007), LPx (r = 0.779) and IL-6 (r = 0.7801). Further, there was a significant negative correlation between GSH and TNF-alpha (r = -0.5336)) and LPx (r = -0.644). CONCLUSION: Increasing dose and duration of arsenic exposure in mice cause progressive increase of oxystress and elevation of cytokines associated with increasing level of collagen in the liver.

Chronic arsenic toxicity: clinical features, epidemiology, and treatment: experience in West Bengal.

Chronic arsenic toxicity due to drinking arsenic-contaminated water has been one of the worst environmental health hazards affecting eight districts of West Bengal since the early eighties. Detailed clinical examination and investigation of 248 such patients revealed protean clinical manifestations of such toxicity. Over and above hyperpigmentation and keratosis, weakness, anaemia, burning sensation of eyes, solid swelling of legs, liver fibrosis, chronic lung disease, gangrene of toes, neuropathy, and skin cancer are some of the other manifestations. A cross-sectional survey involving 7683 participants of all ages was conducted in an arsenic-affected region between April 1995 and March 1996. Out of a population of 7683 surveyed, 3467 and 4216 people consumed water containing As below and above 0.05 mg/L, respectively. Except pain abdomen the prevalence of all other clinical manifestations tested (e.g., pigmentation, keratosis, hepatomegaly, weakness, nausea, lung disease and neuropathy) were found to be significantly higher in As exposed people (water As > 0.05 mg/L) compared to control population (water As level < 0.05 mg/L). The prevalence of pigmentation and keratosis, hepatomegaly, chronic respiratory disease and weakness rose significantly with increasing arsenic concentrations in drinking water. The respiratory effects were most pronounced in individuals with high arsenic water concentrations who also had skin lesion. Therapy with chelating agent DMSA was not found to be superior to placebo effect. However, therapy with DMPS caused significant improvement of clinical condition of chronic arsenicosis patients as evidenced by significant reduction of total clinical scores from 8.90 +/- 2.84 to 3.27 +/- 1.73; p < 0.0001. Efficacy of specific chelation therapy for patients suffering from chronic As toxicity has further need to be fully substantiated. However, supportive treatment could help in reducing many symptoms of the patients. Treatment in hospital with good nutritious diet has been found to reduce symptom score in a subset of placebo treated patients in West Bengal during the course of DMSA and DMPS trial. People should be advised to stop drinking As contaminated water or exposure to As from any other source. The various clinical manifestations should be treated symptomatically.