کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
576132 1453074 2015 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of dissolved humic acid on the Pb bioavailability in soil solution and its consequence on ecological risk
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بهداشت و امنیت شیمی
پیش نمایش صفحه اول مقاله
Effect of dissolved humic acid on the Pb bioavailability in soil solution and its consequence on ecological risk
چکیده انگلیسی
Current risk characterization in ecological risk assessment does not consider bioavailability of heavy metals, which highly depends on physicochemical properties of environmental media. This study was set to investigate the effect of humic acid (HA), used as a surrogate of organic matter, on Pb toxicity and the subsequent effect on risk characterization in ecological risk assessment. Pb toxicity was assessed using Microtox® in the presence and absence of two different forms of HA, particulate HA (pHA) and dissolved HA (dHA). With increasing contact time, the EC10 values increased (i.e., the toxic effects decreased) and the dissolved Pb concentrations of the filtrates decreased. The high correlation (R = 0.88, p < 0.001) between toxic effects determined using both the mixture and its filtrate as exposure media leads us to conclude that the Pb toxicity highly depends on the soluble fraction. Also, reduced Pb toxicity with increasing dHA concentrations, probably due to formation of Pb-dHA complexes, indicated that Pb toxicity largely comes from free Pb ions. Overall, this study shows the effect of HA on metal toxicity alleviation, and emphasizes the need for incorporating the bioavailable heavy metal concentrations in environmental media as a point of exposure in ecological risk assessment.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Hazardous Materials - Volume 286, 9 April 2015, Pages 236-241
نویسندگان
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