State Key Laboratory of Environmental Criteria and Risk Assessment, State Environmental Protection Key Laboratory of Ecological Effect and Risk Assessment of Chemicals, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Science, Beijing Normal University, Beijing 100875, China.
State Key Laboratory of Environmental Criteria and Risk Assessment, State Environmental Protection Key Laboratory of Ecological Effect and Risk Assessment of Chemicals, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Sci Total Environ. 2017 Jun 1;587-588:68-74. doi: 10.1016/j.scitotenv.2017.02.004. Epub 2017 Feb 27.
Arsenic (As) is a common trace element whose oxidation states mainly include four types (-3, 0, +3, and +5), and inorganic As(III) and As(V) are regarded as the most commonly existing forms in aqueous environments. Generally, As(III) has a higher toxicity than As(V) due to the different mechanisms in arsenic toxicity. However, there are few studies about the water quality criteria (WQC) of As(III) and As(V) respectively because of the deficiency of arsenic toxicity data coming from diverse taxonomic groups. In this research, eight native Chinese aquatic organisms were adopted to conduct toxicity tests for As(III) and As(V) to supplement the published toxicity data. The species sensitivity distribution (SSD) method on the basis of the Log-normal model which was the most optimal among eight models was applied to derive WQCs of As(III) and As(V). Results showed that crustaceans were the most sensitive to As(III) and As(V) among all tested species, thus they could be a biological indicator, and the influence of pH values on arsenic toxicity was complex and species-specific. Besides, the sensitivity differences between native and non-native species were observed. Finally, a criterion maximum concentration (CMC) of 167 and 384μg/L for As(III) and As(V), and a criterion continuous concentration (CCC) of 42 and 44μg/L for As(III) and As(V) were derived using native species, regardless of pH values. The WQCs were also verified by other two methods of ETX 2.0 and species sensitivity rank.
砷（As）是一种常见的微量元素，其氧化态主要包括四种类型（-3、0、+3 和+5），无机砷（As(III)）和砷（As(V)）被认为是水环境中最常见的存在形式。通常，由于砷毒性的不同机制，As(III)的毒性比 As(V)高。然而，由于来自不同分类群的砷毒性数据不足，分别针对 As(III)和 As(V)的水质标准（WQC）研究较少。在这项研究中，采用了 8 种本土中国水生生物进行 As(III)和 As(V)的毒性测试，以补充已发表的毒性数据。基于对数正态模型的物种敏感性分布（SSD）方法是 8 种模型中最优化的方法，用于推导 As(III)和 As(V)的 WQCs。结果表明，甲壳类动物对 As(III)和 As(V)最敏感，因此它们可以作为生物指标，而 pH 值对砷毒性的影响是复杂的和特定于物种的。此外，观察到本土和非本土物种之间的敏感性差异。最后，使用本土物种推导了 167μg/L 和 384μg/L 的砷（III）和砷（V）的准则最大浓度（CMC），以及 42μg/L 和 44μg/L 的砷（III）和砷（V）的准则连续浓度（CCC），无论 pH 值如何。还通过 ETX 2.0 和物种敏感性等级的另外两种方法验证了 WQCs。
