ABSTRACT

Agricultural soils were collected from Mocorito river basin, to determine potentially toxic elements (PTEs) subtotal concentrations and geochemical fractionation, and evaluate their environmental and health risks. All sites showed low As and Cr concentrations. Subtotal concentrations (mg/kg) ranged between 6.8 and 25.6 for As, 1.9 and 2.5 for Cd and 22.5 and 55.1 for Cr. These values were classified as moderately contaminated for As, while a considerable contamination was presented for Cd and Cr. Geochemical partitioning revealed that PTEs are strongly linked with residual phase. Arsenic was associated with amorphous Fe-oxyhydroxides. Ecotoxicological indices showed from low (As and Cr) to considerable (Cd) potential ecological risk factors; potential non-carcinogenic risks by As, Cd and Cr, and potential carcinogenic risks by As and Cr. Lithogenic and anthropogenic sources were identified. Arsenic and Cr showed lithogenic influence, while Cd increased, caused by nearby activities, representing an environmental and health risk.

摘要

从 Mocorito 河流域收集农业土壤，以确定潜在有毒元素 (PTE) 的小计浓度和地球化学分馏，并评估其环境和健康风险。所有站点都显示出低 As 和 Cr 浓度。As 的小计浓度 (mg/kg) 介于 6.8 和 25.6 之间，Cd 介于 1.9 和 2.5 之间，Cr 介于 22.5 和 55.1 之间。这些值被归类为 As 中度污染，而 Cd 和 Cr 则被归类为严重污染。地球化学分配显示 PTE 与残留相密切相关。砷与无定形的 Fe-羟基氧化物有关。生态毒理学指标显示从低（As 和 Cr）到相当大（Cd）的潜在生态风险因素；As、Cd 和 Cr 的潜在非致癌风险，以及 As 和 Cr 的潜在致癌风险。确定了岩源和人为源。砷和铬显示出岩性影响，而镉增加，由附近的活动引起，代表环境和健康风险。