Dissolved arsenic, copper, and lead concentrations in surface water within the Klamath Basin (ver. 3.0, October 2022)

Arsenic (As) toxicity is a global environmental and health problem. There are both natural (eg volcanic activity) and anthropogenic sources of As (eg lead arsenate and copper arsenate were commonly used pesticides in the 1900's). Aqueous levels of arsenic in the Klamath Basin (CA, OR), which has a volcanic origin, can exceed at some locations both the Oregon Department of Environmental Quality human health water quality criteria (2.1 ug/L) (Sturdevant, 2011) and the US EPA drinking water limit (10 ug/L) (US EPA., 2001). In this study, dissolved concentrations of As, copper (Cu) and lead (Pb) were measured in more than 30 sites within the Klamath Basin between May and October. Results from samples collected between 2018 and 2022 are reported in this data release. References: Sturdevant, Debra., 2011. Water Quality Standards Review and Recommendations: Arsenic (Draft Report). State of Oregon Department of Environmental Quality. https://www.oregon.gov/deq/FilterDocs/AppEArsenicIssuePaper.pdf US EPA., 2001. Drinking Water Standard for Arsenic (Report No. EPA 815-F-00-015). United States Environmental Protection Agency. https://www.epa.gov/dwreginfo/chemical-contaminant-rules

砷（Arsenic, As）污染毒性是全球性的环境与健康难题。砷的来源可分为天然来源（如火山活动）与人为来源：20世纪时期，砷酸铅与砷酸铜曾作为主流农药被广泛使用。
地处加利福尼亚州与俄勒冈州的克拉马斯盆地（Klamath Basin，地质起源为火山活动），其部分点位的水体砷浓度，同时超出了俄勒冈州环境质量局制定的人体健康水质基准（2.1 μg/L，Sturdevant, 2011）以及美国环境保护署（US EPA）的饮用水限值（10 μg/L，US EPA, 2001）。
本研究于2018至2022年的5月至10月期间，在克拉马斯盆地内30余个采样点位，测定了砷、铜（Cu）、铅（Pb）的溶解态浓度；本次数据发布即包含上述采样的全部结果。
参考文献：
1. Sturdevant, Debra, 2011. 《水质标准评审与建议：砷（草案报告）》. 俄勒冈州环境质量局. https://www.oregon.gov/deq/FilterDocs/AppEArsenicIssuePaper.pdf
2. 美国环境保护署（US EPA）, 2001. 《砷饮用水标准（报告编号：EPA 815-F-00-015）》. 美国环境保护署. https://www.epa.gov/dwreginfo/chemical-contaminant-rules