Concentrations of polycyclic aromatic hydrocarbons (PAHs) in liver samples of green turtles Chelonia mydas stranded in the Potiguar Basin, northeastern Brazil

Polycyclic aromatic hydrocarbons in freshwater organisms from Hubei, Central China: health risk assessment and source identification

Polycyclic aromatic hydrocarbons (PAHs) can be absorbed and accumulated in aquatic organisms, posing a threat to human health through the food chain. However, the concentration, composition, potential source and health risks of PAHs in freshwater organisms remain largely unknown. This study aimed to investigate the presence of PAHs in freshwater organisms in Hubei, Central China. The levels of 16 PAHs in the studied freshwater organisms ranged from 4.31 to 49.60 ng g-1, with an average value of 38.40 ng g-1. Comprising 75-81% of the total, 3-4 ring PAHs were the primary components in freshwater organisms, with an average ratio of 77.3%. Molecular diagnostic ratios (MDR) and principal component analysis (PCA) successfully identified combustion-related contamination as the major source of PAHs in these organisms. The incremental lifetime cancer risk (ILCR) values associated with PAH exposure were higher for crabs and fishes and were greater for children than for adults, suggesting potential carcinogenic risks to humans via the consumption of freshwater organisms. A comparative analysis of PAH concentrations in marine and freshwater organisms showed that the levels of 16 PAHs in marine organisms were more than twice as high as those in freshwater organisms, indicating differing behaviors of PAHs in marine and freshwater environments. Overall, this study significantly enhances the understanding on PAH accumulation in freshwater organisms and provides valuable insights for preventing and controlling PAH pollution in freshwater aquatic products.

First insights into aliphatic and polycyclic aromatic hydrocarbons (PAHs) in hawksbill turtle (Eretmochelys imbricata) eggs from Persian Gulf, Iran

Petroleum pollution in marine ecosystems has raised great concern for both marine organisms and human health. The Persian Gulf, as a significant hotspot of petroleum pollution, is a crucial nesting area for hawksbill turtles (Eretmochelys imbricata) worldwide. In this work concentration level, source, and compositional profiles of polycyclic aromatic hydrocarbons (PAHs) and normal alkanes (n-alkanes) were analyzed in the yolk, albumen, and shell of hawksbill turtle eggs collected from 3 nests on the Persian Gulf coast of Iran. Twenty-eight PAHs and 19 n-alkanes were detected in samples. The highest levels of ƩPAHs and Ʃn-alkanes were found in yolk samples compared to the albumen and shell, possibly due to the high lipid content and lengthy duration of yolk formation. Comparable levels of pollutants were found in eggshells, indicating the potential for turtle eggshells to accumulate organic pollutants. The source of PAHs and n-alkanes in all samples primarily indicates petrogenic, suggesting extensive oil-producing activities and petroleum pollution in the Persian Gulf. Inter-nest variations in levels and profiles of PAHs and n-alkanes were observed in the eggs from the 3 nests, which might be related to the turtle's diets and migration patterns. Although this study provides the first monitoring data on organic pollutants for sea turtles in the Persian Gulf, more complementary researches are required in terms of monitoring petroleum biomarkers in foraging grounds, maternal blood, and their eggs in this region.

Trends in extraction techniques for the determination of organic micropollutants in liver tissues of vertebrates

Determining organic micropollutants in liver samples of apex species is of foremost importance for biomonitoring studies, as it can provide evidence of environmental pollution and exposure of living organisms to chemicals. This review aims to provide a 4-year overview and summarize the trends in the extraction methodologies to determine both polar and non-polar organic micropollutants in liver samples from organisms of higher trophic levels. The dominant extraction techniques including ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE), Soxhlet, and QuEChERS, as well as additional steps and/or modifications applied in the reviewed studies, are presented and critically discussed. The latest trends in these methods as well as a comparison between them considering elapsed time, robustness, cost, and environmental fingerprint are also provided.

Traces of oil in sea turtle feces

In 2019, an oil spill hit the Brazilian Northeast coast causing impact to several ecosystems, including sea turtles' breeding and feeding areas. This study aimed to investigate whether sea turtles were impacted by this oil disaster, correlating the oil found inside feces with a sandy-oiled sample collected on the beach some days after the accident. The fecal samples were collected in the upper mid-littoral reef areas during three consecutive days in February 2020. The results suggested that sea turtles consumed algae contaminated by petroleum. Hydrocarbons composition of oil inside feces was similar to the sandy-oiled sample, suggesting they were the same. Lighter aliphatic and polycyclic aromatic compounds were missing, indicating both sandy-oiled and oil inside the feces had experienced significant evaporation prior to collection. Although the long-term damage is still unknown, the data are novel and relevant to support future research and alert authorities about the risks to sea turtles.