Occurrence, human health, and ecotoxicological risk assessment of pesticides in surface waters of the River Nile’s Rosetta Branch, Egypt

In Egypt, the shortage of freshwater resources and their pollution constitutes a growing concern. Therefore, objectives this study were to (i) monitor occurrence spatiotemporal variations 100 pesticides in surface water samples collected monthly (from July 2018 June 2019) from El-Rahawy, Sabal, Tala sampling sites along Rosetta branch River Nile (ii) identify potential non-carcinogenic health risks for local people through lifetime consumption contaminated drinking water, (iii) perform an ecological risk assessment aquatic organisms upon exposure detected waters based on quotients (RQs) method. Of analyzed, 22 belonging 11 chemical families detected, 75.5% with one or more pesticide residues. The most frequently was malathion (57%), followed by chlorpyrifos (54%), atrazine (23%), carbendazim (20%). Spatial distribution showed that El-Rahawy site had highest load (38.47 ?g/L), Sabal lowest (16.29 ?g/L). Temporal revealed total concentrations summer (27.98 ?g/L) compared spring (23.16 winter (19.18 autumn (11.85 For target hazard quotient (THQ) values less than one. This implies there is no human at under study. However, 13 presented high-risk (RQ > 1), posing organisms.