Sensitivity of Alabama Freshwater Gastropod Species to Nickel Exposure.

This article focuses on assessing the acute toxicity of nickel (Ni) on three endemic freshwater snail species from Alabama—Somatogyrus georgianus, Elimia cahawbensis, and Elimia spp.—and their capacity to accumulate Ni and essential mineral elements. Laboratory exposures over 96 hours revealed species-specific sensitivity, with E. cahawbensis being the most sensitive (96-h LC50 of 88.88 µg/L Ni) and Elimia spp. the least sensitive (96-h LC50 of 328.47 µg/L Ni). Ni accumulation in snail tissues varied by species and was linked to disruptions in uptake of calcium, magnesium, potassium, and sodium, indicating competitive interactions affecting homeostasis. The study highlights the importance of these endemic snails as bioindicators for localized environmental contamination and suggests that water-quality criteria for Ni should consider species-specific bioavailability and toxicity to better protect aquatic life.