Persistent Halogenated Organic Pollutants in Deep-Water-Deposited Particulates from South China Sea

Updated Mini-Review on Polychlorinated Diphenyl Ethers (PCDEs) in Food: Levels and Dietary Intake

Polychlorinated diphenyl ethers (PCDEs) are a class of chlorinated aromatic compounds with structural similarities to polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs). Due to their physicochemical properties, PCDEs are highly resistant to degradation and tend to accumulate in soils, sediments, and aquatic organisms, making them capable of entering and persisting in the food chain. As with other persistent organic pollutants (POPs), diet represents the primary route of human exposure to PCDEs. This mini-review focuses on recent studies evaluating the concentrations of PCDEs in foodstuffs. The most recent available dietary intake, estimated in 2008, was 51.6 ng/day, showing an increase from 41 ng/day (reported in 2004). In both cases, the highest concentrations of ΣPCDEs were observed in fish and seafood (1,094.7 ng/kg wet weight in 2008). Notably, studies indicate that ΣPCDE levels are lower in cooked food samples compared to their raw counterparts. However, the potential health risks associated with dietary exposure to PCDEs remain uncertain, as no tolerable daily intake (TDI) values have been established for these compounds. This gap is directly linked to the absence of assigned toxic equivalency factors (TEFs) for PCDE congeners. Establishing TDIs and TEFs for PCDEs is critical to comprehensively assess their health risks and to inform regulatory and public health interventions.

Occurrence of priority and emerging organic contaminants in cold-water corals and their habitat: A case study in La Herradura Bay (Spain)

Coastal ecosystems are heavily anthropized areas impacted by discharge of chemical pollutants. We present for the first time the occurrence of a wide number of such chemicals in surface water, sediment, suspended particulate matter, and corals from a protected Mediterranean setting, La Herradura Bay (Spain). A seasonal monitoring sampling campaign was conducted in 2021 (winter and summer). This bay is a marine biodiversity hot spot and home for endangered cold-water corals species (Astroides calycularis and Dendrophyllia ramea). Up to 94 target analytes were present in marine samples, with pharmaceuticals being the predominant compound class (up to 37 ng L-1 in seawater and 775 ng g-1 in sediments), especially during the winter season. Uncontrolled untreated wastewater discharges in combination with hydrodynamics dominating in the area seemed to be the major source of contaminants towards the coral colonies inhabiting the bay, which accumulate pharmaceuticals (up to 154 ng g-1), personal care products (UV filters and synthetic fragrances), polycyclic aromatic hydrocarbons, and organophosphate flame retardants, showing log BAFs up to 6.6. Such values were slightly higher in D. ramea than A. calycularis, but not statistically significant differences were observed (p-value >0.05). Further research is encouraged to assess possible damage to cold-water coral species exposed to multiple contaminants.

Toxicity of Metal Oxides, Dyes, and Dissolved Organic Matter in Water: Implications for the Environment and Human Health

This study delves into the critical issue of water pollution caused by the presence of metal oxides, synthetic dyes, and dissolved organic matter, shedding light on their potential ramifications for both the environment and human health. Metal oxides, ubiquitous in industrial processes and consumer products, are known to leach into water bodies, posing a significant threat to aquatic ecosystems. Additionally, synthetic dyes, extensively used in various industries, can persist in water systems and exhibit complex chemical behavior. This review provides a comprehensive examination of the toxicity associated with metal oxides, synthetic dyes, and dissolved organic matter in water systems. We delve into the sources and environmental fate of these contaminants, highlighting their prevalence in natural water bodies and wastewater effluents. The study highlights the multifaceted impacts of them on human health and aquatic ecosystems, encompassing effects on microbial communities, aquatic flora and fauna, and the overall ecological balance. The novelty of this review lies in its unique presentation, focusing on the toxicity of metal oxides, dyes, and dissolved organic matter. This approach aims to facilitate the accessibility of results for readers, providing a streamlined and clear understanding of the reported findings.