Potentially Toxic Elements in Water, Soil, and Plants from an Agroecosystem with Hydrothermal Mud Pools

Mud pools are chemically similar to volcanism and are considered a pollution risk to ecosystems. The mud pools of Los Negritos, Michoacan, Mexico, additionally present untreated semi-urban wastewater discharges, livestock, and agricultural activities. This study aimed to identify sources, interaction, accumulation, spatial distribution, and mobilization of potentially toxic elements in water, soil, and plants of this site. The water is mainly alkaline (pH 7-8.45) with positive Eh values and T in the 17 to 63 degrees C range. The hydrothermal mud pools are the primary source of As found in water (1506 mg L-1), soil (153 mg kg-1), Agrostis sp. (108 mg kg-1), and Zea mays (115 mg kg-1). The potentially toxic elements seem immobilized in soil; even so, they are susceptible to being released when environmental conditions change, which represents a possible threat to the health of consumers by ingestion and bioaccumulation of As from water and corn.