Rivelino Martins Cavalcante

Oil spills along the northeast coast of Brazil have the potential to cause catastrophic contamination of coastal environments and their associated biota. Beyond the direct contamination processes occurring on beaches, oil can also be transported inland by tides through estuaries. In addition, wind-driven transport of oil was observed in nearly all sections studied along the coast. Therefore, this study evaluated the potential of wind to transport oil fragments inland using both direct and indirect methods, including field observations and GIS-based mapping tools. The results identified and quantified oil fragmentation processes and wind-driven transport over relatively large distances (hundreds of meters). The presence of exhumed beachrock, combined with the absence or low elevation of foredunes and the high potential for wind transport, plays a crucial role in trapping oil on the beach surface. These factors further facilitate the fragmentation and inland dispersal of oil particles, allowing them to penetrate deeper into the coastal environment. The findings underscore the importance of assessing the contamination risks posed by oil fragments as they become incorporated into aeolian and other interconnected inland systems.

The introduction of organic pollutants into the Poti River through anthropogenic activities poses a substantial threat to water quality, aquatic ecosystems and the health of communities reliant on local fish consumption. The accumulation of persistent organic pollutants (POPs) and permitted pesticides along the food chain may contribute to increased cancer incidence, placing additional burdens on public health systems. In this context, the present study evaluated the occurrence of these contaminants in fish, estimated daily exposure and assessed the potential health risks associated with their consumption. Pyrethroid pesticides (PPs) were the predominant contaminants in fish muscle, followed by organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). The district of Ibiapaba, exhibited the highest concentrations, suggesting stronger influence from urban and agricultural sources. The species most affected were curimatã and bodó, both characterised by feeding behaviour near the floodplain. In Oiticica, pesticide levels were similar across species, indicating possible agricultural runoff and inadequate waste disposal. Several samples presented carcinogenic risk values above acceptable thresholds, indicating potential harm from fish consumption. The carcinogenic risk assessment indicated that the ingestion of contaminated fish may pose a significant risk to human health due to recognized hazardous contaminants such as PCBs and OCPs. Additionally, detected compounds including pyrethroids, organophosphates, triazines, PBDEs, and organochlorines are associated with endocrine, neurotoxic, and immunotoxic effects. Continuous exposure to these compounds may contribute not only to cancer development but also to other adverse effects, including endocrine and neurological disorders.