Correlation of hexavalent chromium concentration to groundwater hydrochemical zones chemistry

Recent experimental studies in rodents document the spermatotoxic effects of watersoluble hexavalent chromium. Welders comprise, worldwide, a major occupational group with acknowledged exposure to chromium. This study examines the relationship between semen quality and chromium in the urine and blood of a population of 30 tungsten inert gas (TIG) stainless steel welders, 30 mild steel welders and 47 non-welding workers. Each subject provided two to three semen samples. The chromium concentration ranged from 0.17 to 4.74 nmol mmol1 creatinine (median 1.08) in post-shift spot urine and from 6.0 to 46.4 nmol 1-1 in blood. None of several semen parameters deteriorated with increasing level of internal exposure to chromium. Low-level exposure to hexavalent chromium associated with TIG stainless steel and mild steel welding do not appear to be a major hazard for human spermatogenesis.

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Hexavalent chromium removal from municipal wastewater using ferrous salts

Water Practice & Technology ◽

10.2166/wpt.2018.021 ◽

2018 ◽

Vol 13 (1) ◽

pp. 115-124

Author(s):

Benjamin David Martin ◽

Mohammed Qasim Asghar ◽

Eve Germain

Keyword(s):

Hexavalent Chromium ◽

Municipal Wastewater ◽

Aquatic Toxicity ◽

Sewage Treatment ◽

Chromium Concentration ◽

Organic Load ◽

Ferrous Chloride ◽

Water Courses ◽

Study Laboratory ◽

Final Effluent

Abstract Hexavalent chromium is difficult to remove during conventional biological wastewater treatment. This is because the hexavalent form is dissolved and is only sparingly removed by adsorption onto biomass in conventional processes. Hexavalent chromium is of particular concern because of its aquatic toxicity, and an increasing number of wastewater works have effluent discharge limits to protect receiving water courses, some as low as 8 μg Cr L−1. A relatively simple improvement to the removal of chromium could be made by switching the aluminium or ferric solution dosed at most treatment works for the removal of solids, organic load and phosphorus, to a ferrous salt. Ferrous reduces hexavalent chromium to insoluble trivalent chromium, which can be readily settled out of waste streams as a particulate. In the present study, laboratory experiments using real wastewater and ferrous doses of 10 mg Fe L−1 achieve the chromium discharge consent of 8 μg L−1 from initial solution concentrations of up to 40 μg L−1. A ferrous chloride dosing system was subsequently installed at an operational sewage treatment works that has produced an average final effluent chromium concentration of 2.4 μg L−1 (with a maximum of 4.2 μg L−1), despite influent spikes >300 μg L−1.

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Chromium speciation in human blood samples based on acetyl cysteine by dispersive liquid–liquid biomicroextraction and in-vitro evaluation of acetyl cysteine/cysteine for decreasing of hexavalent chromium concentration

Journal of Pharmaceutical and Biomedical Analysis ◽

10.1016/j.jpba.2015.10.018 ◽

2016 ◽

Vol 118 ◽

pp. 1-8 ◽

Cited By ~ 19

Author(s):

Hamid Shirkhanloo ◽

Mehri Ghazaghi ◽

Hassan Z. Mousavi

Keyword(s):

Hexavalent Chromium ◽

Human Blood ◽

Chromium Concentration ◽

Chromium Speciation ◽

Blood Samples ◽

In Vitro Evaluation ◽

Human Blood Samples ◽

Acetyl Cysteine

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Hexavalent chromium removal by using synthesis of polyaniline and polyvinyl alcohol

Water Science & Technology ◽

10.2166/wst.2016.412 ◽

2016 ◽

Vol 74 (10) ◽

pp. 2305-2313 ◽

Cited By ~ 6

Author(s):

Majid Riahi Samani ◽

Parisa Ebrahimbabaie ◽

Hamed Vafaei Molamahmood

Keyword(s):

Heavy Metals ◽

Polyvinyl Alcohol ◽

Hexavalent Chromium ◽

Removal Efficiency ◽

Chromium Concentration ◽

Chromium Removal ◽

Chromium Vi ◽

Pani Composite ◽

Stirring Time ◽

Textile Finishing

Over the past few years, heavy metals have been proved to be one of the most important contaminants in industrial wastewater. Chromium is one of these heavy metals, which is being utilized in several industries such as textile, finishing and leather industries. Since hexavalent chromium is highly toxic to human health, removal of it from the wastewater is essential for human safety. One of the techniques for removing chromium (VI) is the use of different adsorbents such as polyaniline. In this study, composites of polyaniline (PANi) were synthesized with various amounts of polyvinyl alcohol (PVA). The results showed that PANi/PVA removed around 76% of chromium at a pH of 6.5; the PVA has altered the morphology of the composites and increased the removal efficiency. Additionally, synthesis of 20 mg/L of PVA by PANi composite showed the best removal efficiency, and the optimal stirring time was calculated as 30 minutes. Moreover, the chromium removal efficiency was increased by decreasing the pH, initial chromium concentration and increasing stirring time.

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