The Study On Water Quality Criteria Of Heavy Metals Chromium And Nickel In China

Water quality criteria which reflects scientifically the ecological effects ofpollutants is the scientific basis for water quality standards development andenvironmental management. Based on the summarizations of the water quality criteriasystems from different countries, this paper built water quality criteria system ofChina in combination with biota features in China for the protection of freshwateraquatic organisms. The freshwater quality criteria values of chromium and nickelwere derived respectively using water quality criteria system built in this study.Chromium and nickel are ubiquitous heavy metal pollutants in waterenvironment which could cause adverse effects on aquatic life. The toxicologicaldatabase of chromium and nickel in China was establishes through the processes ofliterature research, species selection, quality screening, and data standardization.Their criteria values were derived by different derivation methods. The results asfollowing:（1） The acute and chronic criteria values of Cr⁶⁺for protection of freshwateraquatic life by Toxicity Percentile Rank Method were63.05μg/L and36.00μg/Lrespectively, and those of Cr³⁺were1153.98μg/L and55.16μg/L respectively. Theacute and chronic criteria values of nickel were187.08μg/L and3.50μg/L,respectively.（2） The acute and chronic criteria values of Cr⁶⁺for protection offreshwater aquatic life by Species sensitivity distribution method were56.43μg/L and25.48μg/L respectively, and those of Cr³⁺were1211.65μg/L and28.96μg/Lrespectively. The acute and chronic criteria values of nickel were164.48μg/L and4.32μg/L, respectively. The Biotic Ligand Model（BLM） was incorporated into thewater quality criteria derivation process of nickel for standardization of nickel toxicitydata. The freshwater quality criteria values of heavy metal chromium and nickel werefinally obtained after audit on the criteria derived.Water quality criteria systems of China was built tentatively in this research andthe freshwater quality criteria values of heavy metal chromium and nickel werestudied separately. It promoted the development of water quality criteria in China andprovided the scientific basis for the development of water quality standards ofchromium and nickel in China.