Contaminated Seafood

Shellfish are just one example of seafood that present potential health risks. Illnesses associated with shellfish include hepatitis, cholera, and amnesic shellfish poisoning (ASP). ASP results from an accumulation of domoic acid, produced by algae in some harmful algal blooms (HABs). Domoic acid has been found in seaweed, crabs, mussels, clams, scallops, anchovies, sardines, albacore, halibut, and mackerel, with shellfish accumulating some of the highest levels (Bejarano et al., 2008). Although foodborne illness is hard to track and is often mistaken as the stomach flu, four million people a year contract hepatitis A and E from eating wastewater-contaminated seafood, with roughly 40,000 deaths and another 40,000 cases of long-term disability from chronic liver damage (Shuval, 2003). In a recent study along the coast of Myanmar, Littman and colleagues (2020) identified 5,459 bacterial pathogens in oyster tissue, marine sediments, and seawater, as well as 78 types of microdebris — mostly microplastics but also oils, polymers, and milk powder. They reported that 51% of the pathogens found in the oyster samples were known to be detrimental and of emerging concern to human health. In examining 150 contaminants of emerging concern (CECs) in the environment, a Puget Sound study found 81 CECs in effluent from wastewater treatment plants (treated effluent) and 42 CECs in the tissue of juvenile salmon and sculpin — concentrations high enough to adversely affect growth, reproduction, and behavior (Meador et al., 2016).