Biomimetic Chromatography as a High-Throughput Tool for Screening Bioaccumulation and Acute Aquatic Toxicity of Pesticides.

Modern pesticide risk assessment relies on data on bioaccumulation and acute aquatic toxicity, yet generating such data is labour-intensive and animal-demanding. This study evaluated whether phospholipid affinity of pesticides, quantified by the chromatographic hydrophobicity index CHIIAM obtained from high-throughput gradient biomimetic chromatography, can serve as a surrogate descriptor of these endpoints. Nineteen pesticides representing different chemical and functional classes were analyzed on IAM.PC.DD2 columns, and CHIIAM values were determined. Bioconcentration factors (BCF) in fish and acute toxicity data (96 h LC50 for fish, 48 h EC50 for Daphnia magna) were retrieved from the Pesticide Properties DataBase. CHIIAM ranged from -12.1 to 54.8 and correlated strongly with log10BCF (r = 0.84) and log10LC50 in fish (r = -0.84), and moderately with log10EC50 for Daphnia (r = 0.76). Highly lipophilic pesticides with high CHIIAM showed elevated BCF and low LC50/EC50 values, whereas polar compounds with low CHIIAM exhibited negligible bioconcentration and low acute toxicity. Deviations from these trends, for compounds with specific modes of action, highlighted the contribution of mechanisms beyond membrane toxicity. Overall, CHIIAM measured under high-throughput conditions retains prognostic value for ecotoxicological assessment and may serve as a rapid experimental descriptor to support preliminary screening.