Comparative multi-generational bioassay on individual and mixture toxicity of silver and zinc oxide nanoparticles: effects on growth and reproduction in Artemia salina.

This research compared multigenerational toxicity of individual and combined silver and zinc oxide nanoparticles (AgNPs and ZnONPs) on Artemia Salina, focusing on mortality, growth (weight and length), and reproductive indices. Three consecutive generations (F0, F1, and F2) of Artemia were exposed to AgNPs (0.6 mg L-1), ZnONPs (0.25 and 0.5 mg L-1), and their combinations (AgNPs|ZnONPs). Higher mortality was recorded for F0 and F1 compared to F2 in individual ZnONPs treatments (F0 > F1 > F2); similarly, the highest mortality (62.5 %) occurred in F0, while the lowest (25 %) in F2 exposed to AgNPs|ZnONPs 0.25. Both individual and combined AgNPs and ZnONPs stunted weight growth across all generations. The greatest weight gain suppression (46 %) occurred in combinational treatments in F1, and the lowest (11.7 %) in individual ZnONPs in F2. Among all generations, the lowest length values were recorded for Artemia exposed to AgNPs|ZnONPs. Nearly all treatments delayed (up to 9 days) the emergence of ovary, especially in F2, with AgNPs|ZnONPs delaying the emergence in 60 %-100 % of surviving Artemia. Similarly, nauplius production delayed (1-6 days) across all generations, particularly in F2. The number of neonates also decreased in F0 (14.8 %-53.9 %), F1 (18.3 %-38.5 %), and F2 (28.8 %-61.6 %) following exposure to both individual and combined NPs. The findings indicate that adding AgNPs enhances the biological impact of ZnONPs (additive effect) and suggest transgenerational effects of the experimental NPs- greater growth impairment, longer delays in egg pouch emergence and first breeding time, and the lowest offspring numbers, all observed in F2.