Spatial Distribution and Fuzzy Health Risk Assessment of Trace Elements in Surface Water from Honghu Lake.

Chaoyang Liu,Zhenzhen Qiu,Minsi Xiao,Fei Li,Jingdong Zhang,Ying Cai

doi:10.3390/ijerph14091011

Abstract

Previous studies revealed that Honghu Lake was polluted by trace elements due to anthropogenic activities. This study investigated the spatial distribution of trace elements in Honghu Lake, and identified the major pollutants and control areas based on the fuzzy health risk assessment at screening level. The mean total content of trace elements in surface water decreased in the order of Zn (18.04 μg/L) > Pb (3.42 μg/L) > Cu (3.09 μg/L) > Cr (1.63 μg/L) > As (0.99 μg/L) > Cd (0.14 μg/L), within limits of Drinking Water Guidelines. The results of fuzzy health risk assessment indicated that there was no obvious non-carcinogenic risk to human health, while carcinogenic risk was observed in descending order of As > Cr > Cd > Pb. As was regarded to have the highest carcinogenic risk among selected trace elements because it generally accounted for 64% of integrated carcinogenic risk. Potential carcinogenic risk of trace elements in each sampling site was approximately at medium risk level (10−5 to 10−4). The areas in the south (S4, S13, and S16) and northeast (S8, S18, and S19) of Honghu Lake were regarded as the risk priority control areas. However, the corresponding maximum memberships of integrated carcinogenic risk in S1, S3, S10–S13, S15, and S18 were of relatively low credibility (50–60%), and may mislead the decision-makers in identifying the risk priority areas. Results of fuzzy assessment presented the subordinate grade and corresponding reliability of risk, and provided more full-scale results for decision-makers, which made up for the deficiency of certainty assessment to a certain extent.

Highlights

Surface waters are important sources of domestic water for humans, but they are more sensitive and vulnerable to contaminants due to the extensive area and accessibility to wastewater
The pH, dissolved oxygen (DO), electrical conductivity (EC), and total amount of trace element in surface water from Honghu Lake are shown as Table 3 and Figure 2
There is no direct regulation on the conductivity of surface water and drinking water in China, so the conductivity has to been roughly estimated through the limits of total dissolved solids (TDS) and total hardness [42]

Summary

Introduction

Surface waters are important sources of domestic water for humans, but they are more sensitive and vulnerable to contaminants due to the extensive area and accessibility to wastewater. Surface waters have been polluted owing to wide acceptance of domestic sewage, industry wastewater and agricultural wastewater in China. Trace elements have been confirmed to have potential biological risk, ecological risk, and health risk [1,2,3,4]. The pollution of trace elements in surface water has drawn particular attention globally, and has been widely studied with respect to migration mechanisms [5], toxicity [6], accumulation mechanism [7], ecological hazards [8] and the impact on human health [9,10]. Public Health 2017, 14, 1011; doi:10.3390/ijerph14091011 www.mdpi.com/journal/ijerph

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