The Animas River provides irrigation water in northwestern New Mexico and the Navajo Nation. Concerns regarding the river water quality arose on August 5, 2015, when approximately 11.35 million liters of heavy metal contaminated water was accidentally released from the Gold King Mine into the Animas River. This study sought to determine the total concentrations of 7 heavy metal(loid)s (As, Pb, and Zn as metals of concern and Fe, Mn, Ca, and Cu as metals of interest) using portable X-ray fluorescence (PXRF) in two agricultural fields and compare these values to Environmental Protection Agency (EPA) regional screening levels (RSL). Total concentrations of 6 out of 7 metals were below the RSL; only As exceeded the soil screening value of 7.07 mg kg⁻¹ at some locations in the agricultural fields. We also determined water-soluble (WS) and exchangeable fractions (Ex) of As that might be available for agricultural crop uptake using sequential extractions. The WS-As ranged from 0.014 to 0.074 mg kg⁻¹ and Ex-As ranged from 0.135 to 0.248 mg kg⁻¹ and thus were less than 1 and 3% of the total As concentration respectively (ranging from 5.62 to 14.79 mg kg⁻¹) and not considered a threat for plant tissue accumulation. While the concentrations of As observed in the agricultural fields may have exceeded screening levels, the As was not apparently plant available and its risk to crops was determined to be low.

阿尼马斯河为新墨西哥西北部和纳瓦霍民族提供灌溉用水。2015 年 8 月 5 日，约 1,135 万升受重金属污染的水从金王矿意外排放到阿尼马斯河中，引发了对河流水质的担忧。本研究旨在使用便携式 X 射线荧光 (PXRF) 确定 7 种重金属（类物质）（As、Pb 和 Zn 作为关注金属，Fe、Mn、Ca 和 Cu 作为关注金属）的总浓度两个农田，并将这些值与环境保护署 (EPA) 区域筛选水平 (RSL) 进行比较。7 种金属中有 6 种的总浓度低于 RSL；仅 As 超过土壤筛选值 7.07 mg kg ^-1在农田的一些地方。我们还确定了使用连续提取法可用于农作物吸收的砷的水溶性 (WS) 和可交换级分 (Ex)。WS-As 的范围为 0.014 至 0.074 mg kg ^-1，Ex-As 的范围为 0.135 至 0.248 mg kg ^-1，因此分别低于总砷浓度的 1% 和 3%（范围为 5.62 至 14.79 mg kg ^{-） 1} ) 并且不被视为对植物组织积累的威胁。虽然在农田中观察到的砷浓度可能已超过筛选水平，但砷显然不是植物可用的，并且确定其对作物的风险很低。