Unravelling the suitability of Branchinecta gaini as a potential biomonitor of contaminants of emerging concern in the Antarctic Peninsula region

Abstract

The occurrence and impact of contaminants of emerging concerns (CECs) have been investigated in Antarctica much less than in other parts of the world. Although legacy anthropogenic pollutants can reach Antarctica via long-range transport, CECs mainly originate from local sources. Here, we investigated the ability of a freshwater crustacean, the Antarctic fairy shrimp Branchinecta gaini, to cope with nanoscale titanium dioxide (n-TiO2), a widely used pigment in consumer products (e.g. paintings), including those for personal care (e.g. sunscreens). An in vivo acute short-term exposure study (9 h, n-TiO2 concentration range 50–200 μg ml-1) was performed and the expression levels of several genes involved in stress response were evaluated. No effect on the expression of heat-shock protein chaperone genes was found, with the exception of Hsp70a, which was significantly upregulated at 200 μg ml-1 n-TiO2. Similarly, cytochrome P450 was upregulated at 100 and 200 μg ml-1 n-TiO2, while the expression levels of cathepsin L and of antioxidant genes such as superoxide dismutase and glutathione peroxidase were significantly reduced with increasing concentrations of n-TiO2. This study shows for the first time the responsiveness and sensitivity of an Antarctic freshwater crustacean to n-TiO2 exposure and supports its suitability as a biomonitor of CECs in Antarctica.

Transcriptomic Responses of Antarctic Clam Laternula Elliptica to Nanoparticles, at Single and Combined Exposures: Revealing Ecologically Relevant Biomarkers

“…The characterization analysis confirmed the agglomeration behaviour of n-TiO 2 in high ionic strength media, with an average hydrodynamic size of 872.9 ± 73.8 nm in NSW and a weak negatively surface charge (-11.7 ± 0.7 mV). We previously reported instability and large agglomeration of n-TiO 2 (25 nm, anatase, from Sigma-Aldrich) in Antarctic rock pool waters (González-aravena et al, 2022) and our results are in line with previous studies in seawaters for this NP (reviewed in Corsi et al, 2020Corsi et al, , 2021. For example, Della Torre et al ( 2015) reported the formation of micrometric agglomerates (~970 nm) in artificial sea water for the same n-TiO 2 (Aeroxide © P25) at 10 µg/mL.…”