Acute and chronic dietary exposure to domoic acid in recreational harvesters: A survey of shellfish consumption behavior Environment International

Domoic acid (DA) is a neurotoxin that is naturally produced by phytoplankton and accumulates in seafood during harmful algal blooms. As the prevalence of DA increases in the marine environment, there is a critical need to identify seafood consumers at risk of DA poisoning. DA exposure was estimated in recreational razor clam (Siliqua patula) harvesters to determine if exposures above current regulatory guidelines occur and/or if harvesters are chronically exposed to low levels of DA. Human consumption rates of razor clams were determined by distributing 1523 surveys to recreational razor clam harvesters in spring 2015 and winter 2016, in Washington, USA. These consumption rate data were combined with DA measurements in razor clams, collected by a state monitoring program, to estimate human DA exposure. Approximately 7% of total acute exposures calculated (including the same individuals at different times) exceeded the current regulatory reference dose (0.075 mg DA·kg bodyweight− 1·d− 1) due to higher than previously reported consumption rates, lower bodyweights, and/or by consumption of clams at the upper range of legal DA levels (maximum 20 mg·kg− 1 wet weight for whole tissue). Three percent of survey respondents were potentially at risk of chronic DA exposure by consuming a minimum of 15 clams per month for at 12 consecutive months. These insights into DA consumption will provide an additional tool for razor clam fishery management.

软骨藻酸（Domoic Acid, DA）是一种由浮游植物自然产生的神经毒素，在有害藻华期间会在海产品中富集。随着海洋环境中DA污染水平的升高，亟需识别存在软骨藻酸中毒风险的海产品消费者。本研究针对休闲采捕太平洋竹蛏（Siliqua patula）的捕捞者开展DA暴露评估，以判断是否存在超出当前监管标准的暴露情况，以及捕捞者是否长期处于低水平DA暴露环境中。2015年春季与2016年冬季，研究团队向美国华盛顿州的休闲竹蛏捕捞者发放了1523份调查问卷，以此确定竹蛏的人类食用率。研究将该食用率数据与华盛顿州官方监测项目采集的竹蛏体内DA含量检测结果相结合，以此估算人类的DA暴露量。经计算，约7%的急性暴露总量（包含不同时段的同一受试者）超过了当前监管参考剂量（0.075 mg DA·kg体重⁻¹·d⁻¹），该情况源于食用率高于既往报道、个体体重更低，以及/或食用了DA含量处于法定上限区间的竹蛏（整组织湿重最大允许值为20 mg·kg⁻¹）。3%的调查问卷受访者存在慢性DA暴露的潜在风险——他们每月至少食用15只竹蛏，且持续食用时长至少为12个月。本次关于竹蛏食用与DA暴露的研究结果，将为竹蛏渔业管理提供新的辅助工具。