Exposure of juvenile Danio rerio to aged TiO2 nanomaterial from sunscreen

Abstract

The toxicity of dietary exposure to artificially aged TiO₂ nanomaterial (T-Lite) used in sunscreen cream was studied on Danio rerio. Embryolarval assays were conducted to assess the effects of TiO₂ residues of nanomaterial (RNM) on fish early life stages. Juvenile fishes were exposed by the trophic route in two experiments. During the first experiment, juvenile fishes were exposed to TiO₂ RNM for 14 days by adding RNM to commercial fish food. The second one consisted in producing a trophic food chain. Pseudokirchneriella subcapitata algae, previously contaminated with TiO₂ RNM in growth medium, was used to feed Daphnia magna neonates over a 48-h period. Daphnia were used next to feed juvenile fishes for 7 days. Accumulation of Ti, life traits (survival and growth) and biochemical parameters such as energy reserves, digestive (trypsin, esterase, cellulose and amylase) and antioxidant (superoxide dismutase and catalase) enzyme activity were measured at the end of exposures. As expected in the receiving aquatic system, TiO2 RNM at low concentrations caused a low impact on juvenile zebrafish. A slight impact on the early life stage of zebrafish with premature hatching was observed, and this effect appeared mainly indirect, due to possible embryo hypoxia. When juvenile fish are exposed to contaminated food, digestive enzyme activity indicated a negative effect of TiO₂ RNM. Digestive physiology was altered after 14 days of exposure and seemed to be an indirect target of TiO₂ RNM when provided by food.

Toxicity of Oxidatively Degraded Quantum Dots to Developing Zebrafish (Danio rerio)

“…21 As a further example, exposure to an aged TiO 2 nanocomposite (T-Lite™) used in sunscreens has a small effect on developing zebrafish ( Danio rerio ). 22 To our knowledge, aside from this latter example, effects of weathered eNPs on aquatic vertebrates have not been reported.…”

Morphometric characteristics and time to hatch as efficacious indicators for potential nanotoxicity assay in zebrafish

“…Live embryos were collected at approximately 2 h postfertilization (hpf; blastula stage; Fouqueray et al 2013). Two males and 3 females were transferred to mating tanks (FH-101, Guangdong Boyu Aquarium Industries) late in the afternoon the day before spawning.…”

“…Methylene blue (0.5 mg/ L) was added to the embryo rearing medium to prevent fungal growth. Live embryos were collected at approximately 2 h postfertilization (hpf; blastula stage; Fouqueray et al 2013).…”

“…The impact of nTiO 2 exposure on zebrafish hatching events has been investigated and reported as premature hatching (Kovri znych et al 2013;Ma and Diamond 2013;Fouqueray et al 2013;Samaee et al 2015) or delayed hatching (Yeo and Jo 2007;Xu et al 2012). There are also other studies (e.g., Clemente et al 2014;Wang et al 2014;Yan et al 2014;Jovanovi c et al 2015) in which viability parameters (e.g., hatching events and/or survivability) have been considered to characterize nTiO 2 -induced toxicity.…”

Evidence for TiO2 nanoparticle transfer in a hard-rock aquifer

“…TiO 2 NPs, however, have been classified as potentially cancerous for humans by the International Agency for Research on Cancer (IARC, 2006), so where groundwater is widely used for drinking water, any contamination could have an adverse impact on human health. The adverse impact of these NPs has already been shown on bacteria (Santaella et al, 2014), crustaceans (Fouqueray et al, 2013), mice Ma et al, 2009), plants and human lymphocytes (Ghosh et al, 2010). Consequently, the potential exposure of TiO 2 NPs through groundwater contamination needs to be studied and assessed.…”