Polycyclic aromatic hydrocarbons in sediments and shellfish from Todos os Santos bay, Brazil.

The present study evaluated the occurrence of 24 Polycyclic Aromatic Hydrocarbons (PAHs) in sediments and shellfish (Anomalocardia flexuosa, Crassostrea rhizophorae, and Mytella guyanensis) of Todos os Santos bay (BTS, Brazil). Total PAHs levels ranged from 89 to 921 ng g-1 dry weight (d.w.) in sediments, and from 66 to 505 ng g-1 d.w. in shellfish, signalizing that BTS was moderately contaminated by PAHs, mostly from pyrogenic activities. The bioaccumulation factor (BAF) of total PAHs ranged from 0.20 to 2.9 and did not show a clear trend among the studied species. BAFs of high molecular weight compounds were higher for A. flexuosa (specie found buried in fine sediment), while those of low molecular weight compounds were higher for C. rhizophorae (specie found in the roots of mangrove trees). High concentrations of PAHs, especially benzo[a]pyrene and dibenzo[a,h]anthracene, suggest that contamination compromises shellfish quality and raise concern about seafood consumption safety.

The barnacle Chthamalus bisinuatus is the only sessile invertebrate colonizing oil patches on beachrocks one year after a massive oil spill on the Northeastern Brazilian coast.

A large-scale oil spill has reached over 3000 km of the NE Brazilian coast since August 2019. The cause and origin of this spill remain mysterious, and the impacts on coastal ecosystems have not been clearly understood so far. Despite the efforts to remove the oil (mainly from local communities), oil stains are still present in beaches, mangroves, and beachrocks. In this short report, we describe the occurrence of the barnacle Chthamalus bisinuatus Pilsbry, 1916 colonizing oil spill stains on intertidal surfaces of beachrocks one year after the first oil records. We quickly assessed oil stains across three different reefs located at the Conde municipality, Bahia (NE Brazil), where the species was identified and its density on oil stains calculated. The occurrence of barnacles in oil stains was restricted to zones in the wake of the reefs. Their densities varied from 0 to 238 ind./dm2, with an average of 34 ± 68 ind./dm2. If we account for dead individuals (empty barnacle plates), they correspond to 25.9% of the sampled population. The presence of oil possibly affected barnacle survival rates but did not seem to prevent barnacle individuals from reaching adult sizes. We also found individuals of the snail Echinolittorina lineolata (d'Orbigny, 1840) crawling on these barnacles, indicating that the barnacle assemblages on oil stains are stable enough to provide refuge for these snails. It is not clear if the presence of barnacles on oil reflects the resistance of these crustaceans to the oil toxicity or is just a result of a low substrate selectivity by the cypris larvae.

Persistent organic pollutants (POPs) and personal care products (PCPs) in the surface sediments of a large tropical bay (Todos os Santos Bay, Brazil).

The occurrence and spatial distribution of persistent organic pollutants (POPs) and personal care products (PCPs) were investigated in surface sediments of Todos os Santos Bay. Samples were Soxhlet-extracted and analyzed by gas chromatography coupled with tandem mass spectrometry. Quantification limits (QL) ranged from 0.0025 ng g-1 for POPs to 0.25 ng g-1 for PCPs. Of the POPs studied, only PCBs and DDTs were detectable, with concentrations ranging from