Contaminant concentrations and risks associated with the Pacific oyster in the highly urbanized San Diego Bay.

Contaminant concentrations in filter-feeding shellfish may indicate the health of coastal waters and consumption risks. Widespread expansion of the Pacific oyster (Crassostrea gigas) and its popularity as food make it a useful sentinel. We surveyed intertidal Pacific oysters in San Diego Bay, California for contaminants during summer 2018 and winter 2019.

Persistent organic pollutants in green sea turtles (Chelonia mydas) inhabiting two urbanized Southern California habitats.

Within Southern California, east Pacific green sea turtles (Chelonia mydas) forage year-round, taking advantage of diverse food resources, including seagrass, marine algae, and invertebrates. Assessing persistent organic pollutants (POP) in green turtle aggregations in the Seal Beach National Wildlife Refuge (SBNWR, n = 17) and San Diego Bay (SDB, n = 25) can help quantify contamination risks for these populations. Blood plasma was analyzed for polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs).

Trace metals in green sea turtles (Chelonia mydas) inhabiting two southern California coastal estuaries.

Foraging aggregations of east Pacific green sea turtles (Chelonia mydas) inhabit the Seal Beach National Wildlife Refuge (SBNWR) and San Diego Bay (SDB), two habitats in southern California, USA, located near urbanized areas. Both juvenile and adult green turtles forage in these areas and exhibit high site fidelity, which potentially exposes green turtles to anthropogenic contaminants. We assessed 21 trace metals (TM) bioaccumulated in green turtle scute and red blood cell (RBC) samples collected from SBNWR (n = 16 turtles) and SDB (n = 20 turtles) using acid digestion and inductively coupled plasma mass spectrometry.

Application of sediment toxicity identification evaluation techniques to a site with multiple contaminants.

Sediment toxicity identification evaluations (TIEs) are conducted to determine causes of adverse effects observed in whole-sediment toxicity tests. However, in multiple contaminant scenarios, it is problematic to partition contributions of individual contaminants to overall toxicity. Using data from a site with multiple inputs and contaminants of concern, the authors describe a quantitative approach for the TIE process by tracking toxicity units to determine whether all toxicity is accounted for.