Persistent organic pollutants in sediments, intertidal crabs, and the threatened Olrog's gull in a northern Patagonia salt marsh, Argentina

Highlights: • POP levels in sediments, crabs, and Olrog's gull chicks and eggs were relatively low. • α-Endosulfan, PCB-153, and BDE-47 were the most represented compounds. • POP levels in Bahía San Blas environments suggest their use in recent years. • Bioaccumulation in crabs suggests a risk to upper trophic level predators. - Abstract: Persistent organic pollutants (POPs) are of great concern for the environment. In this study we (a) determine levels and distribution of OCPs, PCBs, and PBDEs in sediments and two crab species (Neohelice granulata and Cyrtograpsus altimanus), (b) assess bioaccumulation in crabs, and (c) explore the occurrence of POPs in the Near Threatened Olrog's gull (Larus atlanticus) chicks and eggs in one of the most important salt marsh environments in the South West Atlantic. Sediments, crabs, and gull chicks and eggs showed POPs presence at low levels; being α-endosulfan, PCB-153, and BDE-47 the most represented compounds. In sediments, pollutant concentrations were lower than those reported in Canadian guidelines for the protection of the aquatic life. POP bioaccumulation was recorded in crabs, suggesting a risk to upper trophic level predators. Further studies are needed to understand the trophic effects of POPs in San Blas bay, particularly on the threatened Olrog's gull.