Dissolved organic matter mitigates the toxicity of silver nanoparticles to freshwater algae: Effects on oxidative stress and membrane function.

The mechanisms underlying the destruction of cell membranes by silver nanoparticles (AgNPs) in the presence of dissolved organic matter (DOM) remain unclear despite extensive studies on the toxicity of AgNPs to the cell membranes of aquatic organisms. This study investigated the impact of dissolved humic acid (DHA) on the toxicity of AgNPs and silver ions (Ag) to Chlorella vulgaris cell membranes. Specifically, this research examined the alterations in membrane lipid peroxidation, cell membrane permeability, fatty acid (FA) profiles, membrane fluidity, and ultrastructural changes in algal cells resulting from Ag and AgNPs, both in the absence and the presence of DHA, as well as the potential cytoprotective effect of DHA.