Toxicity and trophic transfer of P25 TiO NPs from Dunaliella salina to Artemia salina: Effect of dietary and waterborne exposure.

The recent increase in nanoparticle (P25 TiO NPs) usage has led to concerns regarding their potential implications on environment and human health. The food chain is the central pathway for nanoparticle transfer from lower to high trophic level organisms. The current study relies on the investigation of toxicity and trophic transfer potential of TiO NPs from marine algae Dunaliella salina to marine crustacean Artemia salina. Toxicity was measured in two different modes of exposure such as waterborne (exposure of TiO NPs to Artemia) and dietary exposure (NP-accumulated algal cells are used to feed the Artemia). The toxicity and accumulation of TiO NPs in marine algae D. salina were also studied. Artemia was found to be more sensitive to TiO NPs (48h LC of 4.21mgL) as compared to marine algae, D. salina (48h LC of 11.35mgL). The toxicity, uptake, and accumulation of TiO NPs were observed to be more in waterborne exposure as compared to dietary exposure. Waterborne exposure seemed to cause higher ROS production and antioxidant enzyme (SOD and CAT) activity as compared to dietary exposure of TiO NPs in Artemia. There were no observed biomagnification (BMF) and trophic transfer from algae to Artemia through dietary exposure. Histopathological studies confirmed the morphological and internal damages in Artemia. This study reiterates the possible effects of the different modes of exposure on trophic transfer potential of TiO NPs and eventually the consequences on aquatic environment.