HPLC analysis of biomarkers of Toluene and Xylene in human urine samples

Introduction: Urinary Hippuric acid (HA) and Methylhippuric acid (MHA) are considered reliable biomarkers for monitoring exposure to toluene and xylenes. A simple and robust HPLC method for simultaneous determination of HA and MHA in urine samples was developed and validated as per Internation Conference on Harmonization (ICH) Q2 guidelines. Methods: Mobile phase consisting of two solvents A & B, solvent A was 0.1% TFA in water, and solvent B was 0.1% TFA in acetonitrile.  Separation was performed in gradient elution mode and the time program was as follows - Time (min)/%B: 0/20, 4/20, 11/80, 11.1/90, 16/90, 16.1/20, 25/20. The detection wavelength was 205 nm. Results: The limits of detection (LOD) and quantification (LOQ) of HA in urine were 0.3 and 1.0 mg/L, and for MHA were 0.25 mg/L and 1.0 mg/L respectively and the recovery for HA and MHA were 95% and 98.9% respectively.  Conclusion: The developed method was successfully applied for the analysis of urine samples

2321-7871 Weekly Science Research Journal Review Article

Retrospect and prospect of occupationally induced health hazards for plastic industry workers Anupa Yadav and Ashit Kumar Mukherjee In 21st century imagination of life style is almost impossible without utilization of plastic. Consumption of plastic products is increased day by day because plastic goods are light in weight, durable, easy to handle and noncorrosive. In the manufacturing of plastic products, Vinyl chloride monomer and di (2-ethylhexyl) phthalate are widely used, these are carcinogenic in nature and also cause serious health hazards to the exposed workers. Workforce, engaged in this kind of industries, is at high risk of exposure to these carcinogenic/toxic pollutants. On the other hand, consumption of poly vinyl chloride in India will increase up to 3.1 million metric tonne /year by 2016-17.Scarcity of literature, on the combined effect of vinyl chloride monomer and di (2-ethylhexyl) phthalate on human health, is an obstacle for mitigation of the health hazards of workers engaged in plastic industries. In conclusion, the knowledge gap needs to be bridged by undertaking comprehensive study covering environmental and biological monitoring of urinary metabolites of both vinyl chloride monomer and di(2ethylhexyl)phthalate in Indian context

Method for estimation of hippuric acid as a biomarker of toluene exposure in urine by high-performance liquid chromatography after extraction with ethyl acetate

Aim: This study aimed to establish liquid–liquid extraction (LLE) for estimation of hippuric acid (HA) in urine as a biomarker of the toluene exposure by high-performance liquid chromatography equipped with photodiode array detector (HPLC-PDAD). Method: HA in urine was extracted by LLE and determined by HPLC-PDAD. The operating conditions with HPLC were ODS-2 hypersil column (250 mm × 4.6 mm, 5 μm), 0.1% trifluoro acetic acid (TFA) in acetonitrile and 0.1% TFA in water as mobile phase, 1 ml/min flow rate, and wavelength of 205 nm. The validity of the present method was tested by the estimation of HA in urine samples, collected from toluene-exposed (shoe workers) and unexposed or control subjects. Results: Binary gradient system was used to achieve optimum separation. The analytical curve prepared for HA in aqueous solution in the range of 0.5–10 μg/ml showed determination coefficient value (R2) 0.998. Limit of detection and quantification (LOQ) were 0.46 and 1.53 μg/ml, respectively. The coefficients of variance for intraday precision were 1.4% for HA standard (5 μg/ml) and 1.1% for pooled urine, whereas inter-day precision values were 3.2% and 4.9% for HA standard and pooled urine, respectively. Method recovery obtained was 96%–120% for HA solutions containing 2, 3, and 5 μg/ml, demonstrating that precision and recovery of method were satisfactory. Compared to unexposed group, exposed group had significantly more HA. It was found significantly (P < 0.05) higher in urine of exposed workers (32.52 ± 10.91) than unexposed group (16.21 ± 10.14). Conclusion: Sample preparation by LLE is simple and cost-effective for the determination of HA as a biomarker of toluene exposure by HPLC-PDAD. It can be used to detect HA in urine for population exposed to toluene

A study of environmental exposure from cooking fuel use and role of intervention

Background: Combustion of traditional biomass fuels and coal has been found to be associated with exposure to particulates and volatile organic compounds (VOCs) and cause a series of adverse health effects. Characterization-quantification of such exposure achieved so far is not optimum, and establishment of a protective mechanism with proven efficacy is the urgent need. Methods: The present study was planned to characterize exposure from fuel during cooking in a village of India and understand the effect of using intervention measure. In this study, exposure to different pollutants was examined by personal monitoring in different cooking arrangements with traditional and modified oven. Results: It is observed that level of the pollutants has lessened by several folds while cooking with modified oven in comparison to unmodified oven. Such change of pollutants levels with the use of modified oven was found to be statistically significant in cases of benzene (P < 0.001), toluene (P < 0.01), and particulates (P < 0.0001). Conclusions: This study highlights the exposure from indoor air pollution during cooking and promotes use of low-cost protective mechanisms to curb resulting human health adversities. This study also calls for concerted awareness generation activity among the rural population (especially women) regarding adverse health effect of cooking fuels and protective effect of installed mechanisms

Reconditioned monocytes are immunomodulatory and regulate inflammatory environment in sepsis

Abstract Sepsis is caused by dysregulated immune response to severe infection and hyper inflammation plays a central role in worsening the disease. The immunomodulatory properties of mesenchymal stem cells (MSCs) have been evaluated as a therapeutic candidate for sepsis. Reconditioned monocytes (RM), generated from healthy human peripheral blood mononuclear cells (PBMCs) exhibit both macrophage and MSCs-like properties. RM were administered at different stages of sepsis in a mouse model. It reduced serum levels of IL6, MCP-1, IL-10, improved hypothermia, increased survival, and recovery from 0 to 66% when combined with antibiotics in the mouse model. The reduced human leucocyte antigen DR molecules expression on RM enables their co-culture with PBMCs of sepsis patients which resulted in reduced ROS production, and up-regulated TGF-β while down-regulating IL6, IL8, and IL-10 in-vitro. RM are potentially immunomodulatory, enhance survival in sepsis mouse model and modulate inflammatory behaviour of sepsis patient’s PBMCs