Two cases of poisoning by raw taro leaf and how a poison control centre, food safety inspectors, and a specialty supermarket chain found a solution

Abstract

Although the taro plant, Colocasia esculenta, is commonly consumed throughout Asia, Africa, the Pacific Islands, and the Caribbean, its consumption is less common in North America. Exposure to raw or improperly prepared taro is associated with oropharyngeal irritation and swelling and, rarely, airway obstruction. Although cases of toxicity in countries where taro is a staple have been reported, cases in North America have not been described. Here, two cases of oral irritation and swelling in BC residents who ate raw taro leaf, were reported to the British Columbia Drug and Poison Information Centre (BC DPIC) and triggered an investigation involving a regional health authority and the Canadian Food Inspection Agency. Investigators found that the vendor, a chain of ethnic supermarkets, offered no point of sale preparation instructions. The vendor responded initially by posting instructional signage and later by voluntary product withdrawal. Analysis of BC DPIC records between 1 November 2011 and 20 December 2013 identified 11 cases of symptomatic taro exposure, five to the leaf and six to the corm. The two index cases and subsequent investigation illustrate how new foods or foods in unfamiliar contexts may present as calls to a poison control centre and that prevention requires collaboration among public and corporate stakeholders.