Angler exposure to domoic acid via consumption of contaminated fishes

Abstract

Domoic acid (DA) is a neurotoxin that causes amnesic shellfish poisoning, and fish are recog- nized vectors of DA to marine fauna. However, the exposure of anglers through consumption of DA- contaminated fish is unknown. We measured DA in 11 fish species targeted by Santa Cruz Wharf (SCW) anglers in Monterey Bay, California, USA, and sur- veyed anglers regarding their fish consumption pat- terns. In addition, we used California mussel Mytilus californianus DA data provided by the state of Califor- nia and our measurements of DA in seawater to exam- ine the associations between DA in fish viscera versus in mussels and seawater. DA was detected in the vis- cera of 7 fish species commonly consumed by anglers, and toxin uptake in fishes varied according to their diet. DA was almost entirely in the viscera, with low DA concentrations detected in muscle tissue. The majority of anglers (58% of 565) reported consuming their catch, with a small fraction ingesting the viscera. Total DA concentrations in fish decreased significantly after 11 mo storage at -20°C. DA concentration in sea- water and California mussels was correlated with DA in the viscera of some but not all fish groups. We con- clude that SCW anglers who consume their catch are exposed to asymptomatic DA doses, and that exposure is a function of the species and parts consumed, as well as storage methods and DA levels in the seawater when the fish are caught.