Over the last decade, bisphenol A (BPA) has become a chemical of concern in the marine environment. There is little data on BPA levels in the eastern Adriatic Sea, Croatian waters. This study provides concentrations of BPA in marine sediments and suspended matter sampled from the Kaštela Bay (the central part of the Adriatic Sea) for two years. The results obtained show that BPA in sediment samples ranged from 1.05 to 46.31 µg kg⁻¹, while they were higher in the suspended matter, ranging from 1.84 to 81.39 µg kg⁻¹. To demonstrate a possible correlation between BPA concentrations and other parameters in sediment and suspended matter, the granulometric composition and organic matter content were determined. There was no correlation between BPA and investigated sediment characteristics. To assess the possible effects of BPA on marine biota, its possible estrogenic effect was also investigated by calculating estradiol equivalent concentration (EEQ, µg kg⁻¹), the maximum value of which, in this study, was 0.0181 µg kg⁻¹ in the sediment samples and 0.0317 µg kg⁻¹ in suspended matter samples. Based on the presented results, it is unlikely that BPA could cause significant endocrine disruption to marine life in the study area.

Pufferfishes are among the best-known marine organisms that accumulate marine biotoxins such as Tetrodotoxin (TTX). In the Mediterranean Sea, the silver-cheeked toadfish Lagocephalus sceleratus is the most reported TTX-bearer, causing many fatal and non-fatal cases. In Lebanon, no previous studies have measured TTX levels although the possibility of TTX-poisoning is high since L. sceleratus is caught in different sizes and can be mistaken with other small fishes. Hence, this study reports TTX and its analogue 4,9-anhydro TTX in L. sceleratus collected from Lebanese waters in the Eastern Mediterranean Sea. The results show that TTX concentrations in fish tissues varied between 0.10 and 252.97 µg/g, while those of 4,9-anhydro TTX oscillated between 0.01 and 43.01 µg/g. Internal organs of L. sceleratus were the most toxic parts of its body, with the highest TTX levels found in gonads (mainly ovaries) and liver, followed by the muscles and skin with concentrations always exceeding the safety level. Toxicity fluctuations of L. sceleratus, its expansion, ecological and economic effects were also elucidated. Based on the present findings, it has been confirmed that L. sceleratus constitutes a health, ecological and economic risks, and therefore its trade in seafood markets should be banned to avoid any potential intoxication.

The marine diatoms Pseudo-nitzschia spp. are globally distributed primary producers, with certain species capable of producing neurotoxin domoic acid (DA), causing amnesic shellfish poisoning (ASP). This study investigates the toxicity and growth rates of Pseudo-nitzschia species isolated from aquaculture areas in the Central Adriatic Sea. A total of 54 strains from eight species were analysed, with strains originating from four different study sites. Growth rates and toxin production were examined across different growth phases in other species and strains. Most species, including P. allochrona, P. calliantha, P. delicatissima, P. fraudulenta, P. galaxiae, P. mannii, and P. multistriata, did not produce DA at any growth phase. The only species that showed toxin production, at 18 °C was P. pseudodelicatissima (0.0007–0.0250 pg cell⁻¹). Notably, the majority of P. pseudodelicatissima strains were toxic in the decay phase and some strains showed continuous toxin production throughout all growth phases. The highest growth rates for the analysed species were recorded in strains of P. delicatissima, which also exhibited the highest cell abundance (8.19 × 10⁵ cell mL⁻¹), followed by the species P. allochrona, P. mannii and P. pseudodelicatissima.