The Bureau of Fisheries and Aquatic Resources (BFAR) in Eastern Visayas has warned the public against gathering, selling, and eating shellfish from several coastal areas after seawater samples tested positive for a red tide organism.
BFAR is referring to Pyrodinium bahamense, a microorganism associated with red tide and toxins that can cause paralytic shellfish poisoning.
In an advisory issued Wednesday, BFAR said seawater samples from Irong-Irong Bay in Catbalogan City, Samar, and Carigara Bay, covering the waters of Babatngon, San Miguel, Capoocan, Barugo and Carigara in Leyte, tested positive for Pyrodinium bahamense.
BFAR also reiterated the existing shellfish ban in Matarinao Bay in Eastern Samar, covering the municipalities of General MacArthur, Quinapondan, Hernani and Salcedo, after shellfish meat samples collected from the area tested positive for red tide toxins.
The ban remains in effect under Shellfish Bulletin No. 23.
Red tide refers to the high concentration or bloom of certain microscopic algae and other microorganisms in seawater. Some species produce toxins that accumulate in shellfish such as mussels, oysters, clams, and other bivalves.
Water may sometimes appear reddish or discolored during an algal bloom, although a harmful algal bloom does not always visibly turn the water red. This is why laboratory testing is necessary to determine whether seafood harvested from affected waters is safe for consumption.
Pyrodinium bahamense is an organism known to produce paralytic shellfish toxins. Shellfish can accumulate these toxins as they filter-feed in contaminated waters without necessarily becoming visibly spoiled.
BFAR advised the public to refrain from gathering, selling, and eating all types of shellfish and Acetes species, or alamang, harvested from the affected areas.
BFAR clarified that fish, squid, shrimp, and crab from the affected waters may still be consumed, provided they are fresh and properly prepared.
The agency advised consumers to remove the internal organs, including the intestines and gills, and thoroughly wash these seafood products before cooking.
BFAR stressed that the shellfish ban should be observed while the affected waters remain positive for red tide toxins because cooking does not destroy the toxins accumulated by contaminated shellfish.
The agency continues to monitor the affected coastal areas through regular water and shellfish sampling. The public is advised to await further BFAR advisories before resuming the gathering and consumption of shellfish from areas covered by the ban.