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The drinking water and food are main pathway entry of the As in humans and animals. Their in-takes cause diseases i.e. skin cancer, vascular disorder, etc. A wide variety of the rice is cultivated in the central India. The field soil and rice cultivated in the summer season at Koudikasa village, central India were selected for the As contamination studies. The concentration (n = 20) of total- As (AsT) in the field soil, rice grain, husk, straw and root was ranged from 44 - 270, 0.17 - 0.72, 0.40 - 1.58, 2.5 - 5.9 and 204 - 354 mg/kg with mean value of 126 ± 28, 0.47 ± 0.07, 0.83 ± 0.15, 4.2 ± 0.5 and 276 ± 21 mg/kg, respectively. The total arsenic, monomethylarsenonate, dimethylarsinite and inorganic As in the rice grain are quantified.

Background Human exposures to inorganic arsenic (iAs) have been linked to an increased risk of diabetes mellitus. Recent laboratory studies showed that methylated trivalent metabolites of iAs may play key roles in the diabetogenic effects of iAs. Our study examined associations between chronic exposure to iAs in drinking water, metabolism of iAs, and prevalence of diabetes in arsenicosis-endemic areas of Mexico. Methods We used fasting blood glucose (FBG), fasting plasma insulin (FPI), oral glucose tolerance test (OGTT), glycated hemoglobin (HbA1c), and insulin resistance (HOMA-IR) to characterize diabetic individuals. Arsenic levels in drinking water and urine were determined to estimate exposure to iAs. Urinary concentrations of iAs and its trivalent and pentavalent methylated metabolites were measured to assess iAs metabolism. Associations between diabetes and iAs exposure or urinary metabolites of iAs were estimated by logistic regression with adjustment for age, sex, hypertension and obesity. Results The prevalence of diabetes was positively associated with iAs in drinking water (OR 1.13 per 10 ppb, p < 0.01) and with the concentration of dimethylarsinite (DMAsIII) in urine (OR 1.24 per inter-quartile range, p = 0.05). Notably, FPI and HOMA-IR were negatively associated with iAs exposure (β -2.08 and -1.64, respectively, p < 0.01), suggesting that the mechanisms of iAs-induced diabetes differ from those underlying type-2 diabetes, which is typically characterized by insulin resistance. Conclusions Our study confirms a previously reported, but frequently questioned, association between exposure to iAs and diabetes, and is the first to link the risk of diabetes to the production of one of the most toxic metabolites of iAs, DMAsIII.

This paper describes a direct method for arsenic determination and speciation in wine samples by hydride atomic emission spectrometry with inductively coupled plasma (ICP-AES). Optimization of the method included investigation of several parameters that impact the intensity of spectral lines: concentration of reaction media (hydrochloric acid), reduction reagent concentration (sodium borhydride), power generator and the carrier flow rate. The effect of ethanol on spectral lines was especially investigated because it enabled arsenic determination without prior preparation. Optimal conditions for As(III) were 8 mol/L HCl and 0.1% NaBH(4), for dimethylarsinite (DMA) determination 0.005mol/L HCl and 0.02% NaBH(4), and for As(V) 4 mol/L HCl and 2% NaBH(4). Total arsenic was determined in samples after their treatment in a microwave digestion unit. Results were compared to the FIA method, arsenic was determined with the standard addition method, and the results showed agreement. Detection limits (mu g/L) for determination of As(V), DMA, and As(III) were found to be 0.4, 0.6, and 0.10, respectively. Good recoveries (89.9-102.0%) of added spikes were obtained for all samples. The proposed method has been validated by means of reference materials and the results obtained were in agreement with certified values.