Red tide has remained in two bays in Samar provinces this week, largely due to changing weather patterns, the Bureau of Fisheries and Aquatic Resources (BFAR) said Friday. The BFAR regional office said in its latest advisory that the phenomenon persists in San Pedro Bay in Samar and Matarinao Bay in Eastern Samar. 'The presence of toxic red tide is beyond the regulatory limit. All types of shellfish and alamang gathered from these areas are not safe for human consumption,' the BFAR said. The fisheries bureau has stepped up its monitoring of these coastal waters and reactivated its information drive system to alert the public and inform affected local government units (LGUs). The BFAR requested LGUs in these bays to also heighten their watch against the gathering, trading and consumption of shellfish to prevent paralytic shellfish poisoning (PSP). PSP occurs after ingesting bivalve shellfish, such as mussels, oysters, and clams, which contain toxins. Symptoms include tingling of the lips and tongue, whi ch may begin within minutes of eating toxic shellfish or may take an hour or two to develop. This may progress to tingling of the fingers and toes and then loss of control of the arms and legs, followed by difficulty in breathing. Fish, squid, shrimp and crabs harvested in these areas are safe to eat 'provided that they are fresh and washed thoroughly and internal organs, such as gills and intestines, are removed before cooking.' (PNA) Source: Philippines News Agency