Fish and other marine products consumption is the main route of heavy metal exposure to human which poses health risks if taken in high dosage. On the other hand, the nutritional benefits of fish are mainly due to the content of high-quality protein and high content of the two kinds of omega-3 polyunsaturated fatty acids (PUFA): eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The study aims to assess and compare the benefit-risk ratio for the consumption of commonly-consumed fish and products in Metro Manila. Fish and product samples were analyzed for moisture, crude fat, heavy metals (As, Cd, Pb) and fatty acid profile (saturated, mono-and polyunsaturated) including omega-3 fatty acids EPA and DHA. These findings generally indicate that the consumption of fish and products studied posed no risk to human health. Essential fatty acids EPA and DHA were highest for dried anchovy, Stolephorus indicus (1.5 and 7.3mg/g sample); mussel, Mytilus smaragdinus (1.5 and 1.0mg/g sample); round scad, Decapterus macrosoma (0.9 and 3.4mg/g sample); and skipjack tuna, Auxis thazard (1.1 and 3.9mg/g sample). The hazard quotients of essential fatty acids versus heavy metals were also less than 1 except for Cd in squid (1.8), In the case of dried sardine (19.9), squid (1.8), shrimp (3.4), and skipjack tuna (1.7), these foods should be monitored regularly. In conclusion, the target hazard quotients for most of the fish and products showed values less than 1, which suggest that health risks were insignificant.

This study determined the biosorption capacity of algal waste, obtained through agar extraction from Gracilaria tenuistipitata, a common red seaweed in the Philippines and potential biosorbent, on Zn2+ ions. Agar was extracted from the seaweed and characterized through Fourier-transform infrared spectroscopy (FT-IR). The algal waste was then subjected to a biosorption study involving various Zn2+ standards. Atomic absorption spectroscopy (AAS) and FT-IR were employed to evaluate sorption processes. Biosorption data was analyzed using Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherms which yielded  values of 0.9680, 0.8103, and 0.5254, respectively. The Langmuir ( ), Freundlich ( ), and D-R ( ) constants garnered were 0.0231 L/mg, 0.9829 mg/g, and 2.159  10-6 mol2 J-2 respectively, qualifying the adsorption of Zn2+ ions onto the algal waste as a favorable and physical process. FT-IR spectra analysis suggests that carboxylic acid and amide groups are involved in biosorption, possibly an ion-exchange process taking place for the uptake of Zn2+ ions. It was concluded that G. tenuistipitata waste is a promising biosorbent for Zn2+ ions. Performing the biosorption procedure in triplicates and the inclusion of kinetic studies are recommended to improve and ensure the accuracy in determining biosorption capacity and optimization in future studies.

Seaweeds like Caulerpa lentillifera and Kappaphycus alvarezii are used as main ingredients in Filipino delicacies. There is a need to investigate the mineral availability, dietary fiber contents, and short-chain fatty acid fermentation products of these Philippine seaweeds to assess its nutritional and health benefits. Results show that C. lentillifera contain higher levels of iron, zinc, and calcium (430.93 ± 1.46, 1.09 ± 0.19, and 988.44 ± 5.07 mg/100g, respectively) compared with K. alvarezii (11.34 ± 0.14, 0.29 ± 0.01, and 262.98 ± 2.83 mg/100g, respectively). The availability of calcium was shown to be higher in both seaweeds (94.10 - 96.45 %Ca) than iron and zinc availabilities. Both samples exhibited high amounts of dietary fibers. The soluble, insoluble, and total dietary fiber contents of K. alvarezii (16.73 ± 0.03, 42.24 ± 1.04, and 58.97 ± 1.01 g/100g, respectively) were higher than that of C. lentillifera (3.50 ± 0.41 g/100g for soluble, 27.17 ± 0.09 g/100g for insoluble, 30.67 ± 0.32 g/100g for total dietary fiber). In vitro fermentation using human fecal inoculum afforded short chain fatty acids (SCFA). The SCFA content analysis using HPLC showed that K. alvarezii produced propionate (35.53 ± 2.00 g/100g) and butyrate (3.19 ± 0.16 g/100g) SCFAs while C. lentillifera only produced propionate (15.92 ± 0.45 g/100g) SCFA suggesting the potential of these seaweeds for the prevention of some diseases.