Food Safety Focus (62nd Issue, September 2011) – Food Incident Highlight

Red Tide and Food Safety

In mid-August, a number of algal blooms, commonly known as red tides , were reported in western and southern waters of Hong Kong. According to the Agriculture, Fisheries and Conservation Department (AFCD), the red tides spotted were formed by Protopolykrikos distortus, which is a non-toxic red tide causative species.

In general, dense concentrations of phytoplankton can clog fish gills and cause suffocation. When toxic algae are involved, the concentration of toxin in shellfish in the affected waters may increase. These toxins cause little effect on the shellfish, but are toxic to human.

The government has established the Red Tide/Harmful Algal Bloom (HAB) Management Framework in 1998, with the AFCD as the coordinator, to provide coordination, monitoring and responses to red tide incidents. To ensure food safety, further to samples taken under the routine surveillance, the Centre for Food Safety (CFS) will step up sampling in accordance to the action plan. The CFS will take samples at retail outlets along the possible distribution chains of the affected areas if there is presence of potentially harmful species of algae.