Environmental impacts of oil on the east coast of the Brazilian Northeast Coast: sediment toxicity on aquatic organisms and environmental risk

Abstract

Since August 2019, large amounts of oil have started to appear on the beaches of the Brazilian northeast coast, spreading along the coast, for thousands of kilometers and reaching beaches, coral reefs, estuaries, rocky shores and other environments. The arrival of small amounts of oil continues. One way to quantify the impacts caused by an oil spill is essential to know the toxic effects associated with its components in different environmental compartments, such as water and sediment. This project aims to determine the toxicity generated by the oil's arrival on the coast of some Brazilian states, considering sediment samples obtained in coastal environments of the Brazilian NE. It is also intended to assess whether there will be toxicity after the end of the event and carrying out cleaning actions, in order to determine possible long-term effects and the efficiency of cleaning actions. Samples obtained during the oil arrival event will be analyzed to determine the quantities of aliphatic and polycyclic aromatic hydrocarbons. In addition, another rate will be characterized for toxicity. With the aqueous fractions (elutriates or sediment-water interface), toxicity tests on embryonic development of sea urchin Echinometra lucunter will be carried out. Samples of integral sediment will be evaluated for toxicity on amphipod Tiburonella viscana and copepod Nitocra sp. In addition, chemical and ecotoxicological results will be integrated through multiple correlations and multivariate analyzes. The chemical and ecotoxicological results will be spatialized, through GIS maps, in order to determine the relationship between the arrival of the oil in each location and the levels of contamination and toxicity. The identification of the degree of contamination and toxicity of these oils will allow a more accurate assessment of the impact caused by the oil on the water column and on the sediments after the spill occurred on the Brazilian coast since August 2019. (AU)