Perceptions of seafood safety are a known driver of seafood demand, and misinformation about seafood safety has generated documented welfare losses in seafood markets. Welfare losses known as avoidance costs can occur when consumers respond to imperfect information about a contamination event, perceiving a health risk from seafood consumption where one does not exist. Furthermore, contamination events can enable other indirect economic impacts in the form of welfare transfers within the seafood supply chain. Here we explore the indirect economic impacts generated by the prolonged 2015 harmful algal bloom event in California. During this event, harmful algae produced high levels of domoic acid (a neurotoxin), resulting in closures for all commercial Dungeness crab fisheries in California that lasted roughly four and a half months. To estimate the impacts of the event, we investigate whether Dungeness crab prices, both at the ex-vessel and consumer levels, were negatively impacted by the event after the closures were lifted and the crab was declared safe to eat. We find ex-vessel prices fell by at least 9.6% while consumer prices were not impacted. We put forth three competing theories to explain these outcomes and discuss the efficiency and distributional implications of each alternative.

中文翻译：

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有毒藻类事件的市场影响：加利福尼亚大堡礁案例

对海产品安全的看法是海产品需求的已知驱动因素，有关海产品安全的错误信息已导致海产品市场的福利损失。当消费者对有关污染事件的不完整信息做出反应时，就会发生被称为避免成本的福利损失，认为海鲜消费存在健康风险而不存在健康风险。此外，污染事件可以在海产品供应链中以福利转移的形式产生其他间接经济影响。在这里，我们探讨了 2015 年加州长期有害藻华事件产生的间接经济影响。在这次事件中，有害藻类产生了高水平的软骨藻酸（一种神经毒素），导致加利福尼亚州所有商业邓杰内斯蟹渔业关闭，持续了大约四个半月。为了估计该事件的影响，我们调查了在取消关闭并宣布螃蟹可以安全食用后，Dungeness 螃蟹价格（无论是在船外还是消费者层面）是否受到该事件的负面影响。我们发现出厂价至少下降了 9.6%，而消费者价格没有受到影响。我们提出了三个相互竞争的理论来解释这些结果并讨论每个替代方案的效率和分配影响。