Ciguatera Fish Poisoning (CFP) is primarily caused by ingesting reef fishes contaminated with ciguatoxins (CTX) produced by the Gambierdiscus species. The unpredictability of this type of food poisoning poses risks to public health and adversely affecting the fish trade industry. This study aimed to provide useful information on ciguatera in the Philippines. Different reef fish species and host-macroalgae for benthic dinoflagellates were collected in Visayan and Sibuyan Seas. Ciguatoxins were extracted from reef fish samples, and toxicity was determined qualitatively using mouse bioassay. Meanwhile, cell density estimation of toxic benthic dinoflagellates isolated from the host-macroalgae was done through microscopy. It was observed that 4.46% of the total reef fish samples were positive with ciguatoxins. Spatially, Carles, Iloilo in Visayan sea had the highest number of toxic specimens belonging to Epinephelus merra, Lethrinus lentjan, Lutjanus campechanus, Scarus quoyi, Siganus guttatus, and Sphyraena barracuda. Based on data gathered from three sampling sites, fish toxin occurrence is observed to be site-specific. Geographical conditions affect the frequency of toxic samples. Moreover, fish weight is not a good predictor of fish toxicity. For toxic benthic dinoflagellates, Gambierdiscus spp. were observed to have the lowest cell density count among other dinoflagellates averaging 7-115 cells per 100 g macroalgae. On the other hand, Ostreopsis spp. had the highest average cell density of 118-1,455 cells per 100 g macroalgae, followed by Prorocentrum spp. (207-594 cells per 100 g macroalgae). Fish toxicity is directly proportional to the occurrence of benthic dinoflagellates in areas as seen during dry season. Monitoring and management of CFP on identified reef fish vectors and its causative benthic dinoflagellates in the area are necessary to promote food safety and fair trade practice.

The Philippines is an archipelagic country that belongs to the biologically diverse Pacific Coral Triangle, rich in marine resources, including corals, reef fishes, and algae. This explains the continuous sustenance of the Filipinos on fish as a major protein source. Despite their contribution to human consumption, some commercially important coral reef fishes are a threat to food safety, compromising public health. Currently, ciguatera fish poisoning (CFP) has been focused on by scientists since it is the most frequently reported seafood-toxin illness in the world acquired from contaminated coral reef fishes. The present study investigates the contamination of reef fishes in the West Philippine and Sulu Seas using animal assay. Ciguatoxins (CTX) are present in commercially important reef fishes such as barracuda (Sphyraena barracuda), parrotfish (Scarus quoyi), rabbitfish (Siganus guttatus), grouper (Plectropomus leopardus), moray eel (Gymnothorax melanospilos), and snapper (Lutjanus campechanus). Scarus quoyi had the highest toxicity of 0.65 ± 0.55 ppb and 0.48 ± 0.36 ppb found in flesh and viscera, respectively. Although higher toxicities were observed from fish viscera, toxicities between fish parts did not vary greatly (p > 0.05). Positive samples exceeded the 0.01 ppb guideline established by the US Food and Drug Administration and the Philippines’ regulatory limit set by the Bureau of Fisheries and Aquatic Resources. Symptoms of mice showing the presence of Pacific CTX-1 were noted. Since mouse bioassay was used in screening reef fishes that pose non-specificity and insensitivity problems, the researchers suggest that analytical methods must be used in characterizing and quantifying these types of toxins. Establishing the methodologies in detecting CTX would greatly help monitor and manage CFP in commercially identified reef fishes in the country.

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Bivalves such as scallop Bractechlamys vexillum are considered an essential resource for livelihood and revenues in the Visayan Sea, central Philippines. To date, there are several reports that the local marine ecosystems are contaminated with heavy metals like cadmium; hence, these species are also susceptible to bioaccumulation of cadmium because they feed mainly by filtering particles from contaminated water. In recent studies, scallops are suggested to be a potential bioindicator for cadmium contamination due to their ability to accumulate and tolerate the metal. This research aims to examine the anatomical distribution of cadmium in B. vexillum and measure the relationship between shell weight and cadmium concentration. The sites for this study include Carles, Iloilo, Madridejos, Cebu, and Cawayan, Masbate. Five organs were analyzed: adductor muscle, digestive gland, gonad, gill, and mantle. The analysis for quantification of cadmium in the different scallop parts was carried out by Inductively Coupled Plasma – Optical Emission Spectrometry (ICP-OES Model ICPE-9820, Shimadzu, Kyoto, Japan). Results showed that cadmium preferentially accumulates in the digestive gland, accounting for 76.39% of the total metal concentration. Moreover, a significant positive correlation (r = 0.798, p < 0.01) between the cadmium content in the whole digestive gland and shell weight were observed. Thus, this tissue tends to have a potential marker of metal contamination in the environment.

Manila Bay contributes significantly to the Philippines’ economy through industry, trade, tourism, and agriculture. However, microbiological contamination in the bay is putting it at risk in the present. Pathogen contamination of the water poses a serious threat to food safety, implicating public health. To address these concerns, the present study examined the prevalence of Salmonella in six different aquaculture commodities, Perna viridis (mussel), Crassostrea iridalei (oyster), Scylla serrata (crab), Penaeus spp. (shrimp), Oreochromis niloticus (tilapia), and Chanos chanos (milkfish), as well as in environmental water from growing areas. A tandem approach of culture-based and real-time PCR methods for the isolation and identification of Salmonella was carried out. To accurately identify the isolates, a real-time PCR Taqman assay based on the invA gene was used. Among the fishery resources examined, no positive samples were observed from C. chanos and O. niloticus. In addition, Salmonella was found in twenty (20) samples, representing 16.26% of all aquaculture commodities collected. Furthermore, Salmonella was found in 13.58% of the 81 environmental water samples examined. P. viridis had the highest prevalence of 55.55% out of 18 samples examined. Samples contaminated with Salmonella failed to meet the regulatory limits set by BFAR FAO 210 series 2001 and EC No. 2073/2005. In addition, it was observed that the sample matrix had a significant impact on the presence of Salmonella (p < 0.05). However, the spatial and temporal distribution of Salmonella did not vary greatly (p > 0.05). This study underscores the importance of imposing strict policies by regulatory bodies to prevent diseases, thus avoiding severe health implications.