Short-term effects of acrylamide exposure towards fatty acids' composition and histological features of the rayed trough-shell Mactra stultorum' branchial tissues.

Acrylamide (ACR) is a broad-spectrum water-soluble monomer used in polymer production. Through assorted pathways, such as wastewater offload, industrial effluents, and leaching from polyacrylamide grouting materials, ACR can reach aquatic environments and readily influence common organisms in coastal areas near urban or industrial zones, notably edible clams. The current study evaluated the ACR impact on the fatty acids (FA) composition in the rayed trough-shell Mactra stultorum gills. Bivalves were exposed to ACR-graded concentrations (5,10, and 20 mg/L) for 5 days. At the end of the trial, the gills' ACR burden exhibited significant increases reflecting its harmful influence. Our results showed that ACR promoted oxidative imbalance, highlighted by increased hydrogen peroxide (H₂O₂) levels. A considerable decrease in saturated fatty acids (SFA) in ACR-treated clams was recorded. In terms of n-6 (Omega 6) and n-3 (Omega 3) polyunsaturated fatty acids series, we noted a high induction in arachidonic (ARA, C20:4n-6) (and its precursor linoleic acid (LA, C18:2n-6)), eicosapentaenoic (EPA, C20:5n-3), and docosahexaenoic (DHA, C22:6n-3) acids level. The results showed a significant increase in the dienoic non-methylene-interrupted fatty acid (NMID, C22 :2) amounts in ACR-treated clams. While our findings revealed that this electrophile produced pronounced effects on the lipid fraction of M. stultorum gills, these results were further confirmed by the harmful histological anomalies. Our research outlines the urgency of further investigations into ACR-induced metabolic impacts to fully assess its long-term outcomes on aquatic ecosystems.