Impacts of Petroleum Fuels on Fertilisation and Development of the Antarctic Sea Urchin Sterechinus neumayeri.

Antarctic marine environments are at risk from petroleum fuel spills as shipping activities in the Southern Ocean increase. Knowledge of the sensitivity of Antarctic species to fuels under environmentally realistic exposure conditions is lacking. In this study, the toxicity of three fuels, Special Antarctic Blend diesel (SAB), marine gas oil (MGO) and intermediate fuel oil (IFO 180) to a common Antarctic sea urchin Sterechinus neumayeri was determined. Sensitivity was estimated for early developmental stages from fertilisation to the early 4-arm pluteus in toxicity tests of up to 24 d duration. The effects of the water accommodated fractions (WAFs) of fuels were investigated under different exposure scenarios to determine the relative sensitivity of stages and of different exposure regimes. Sensitivity to fuel WAFs increased through development. MGO and IFO 180 were more toxic than SAB, with EC50 values for the most sensitive pluteus stage of 3.5, 6.5 and 252 µg/L THC respectively. Exposure to a single pulse during fertilisation and early embryonic development shows similar toxicity patterns to those observed from continuous exposure. This work shows that exposure to fuel WAFs during critical early life stages affects the subsequent viability of larvae, with consequent implications for reproductive success. The sensitivity estimates for S. neumayeri generated in this study can be utilised in risk assessments for the management of Antarctic marine ecosystems. This article is protected by copyright. All rights reserved.