Human health risk associated with heavy metals from consumption of Asiatic Clam, Corbicula fluminea, from Laguna de Bay, Philippines.

Laguna de Bay, the largest and nationally significant freshwater lake ecosystem in the Philippines, has been increasingly subjected to anthropogenic pressures over the years. Domestic, agricultural, and industrial activities in the surrounding areas have contributed directly and indirectly to the deterioration of the lake's overall ecological health and integrity. This study assessed the chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), and cadmium (Cd) contamination in Asiatic clam, Corbicula fluminea, using quadrupole inductively coupled plasma-mass spectrometry. Estimated daily consumption of Asiatic clam was determined through a social survey. The data from analytical analysis and social surveys were utilized to calculate the target hazard quotient (THQ) to determine the potential health risks of consuming heavy metal-enriched clams to fishing households. Results from the Knowledge, Attitude, and Practices (KAP) survey indicated that the majority of the respondents have an acceptable level of knowledge on the hazards posed by the intake of contaminated clams but disapproved the banning of its collection and consumption. Sampled households with high consumption rates in all municipalities except Victoria were also found to be exposed to imminent health risk due to the high toxicity level of As based on their THQ values. Overall, one-third of the fishing households exposed to elevated health risk based on their total target hazard quotient (TTHQ) values already warrant a concern. The potential human health risks validate the worsening condition of Laguna de Bay. Integrative and holistic management of the lake through collaborative efforts of various stakeholders and institutions is necessary, to restore the health of the ecosystem and safeguard the health of the public.

Toxocara (Nematoda: Ascaridida) and other soil-transmitted helminth eggs contaminating soils in selected urban and rural areas in the Philippines.

The extent of contamination of soils with soil transmitted helminthes (STH) eggs, particularly Toxocara, was determined in selected urban and rural towns of Laguna, Philippines. Soil samples were collected from public schools, house yards, and empty lots. Results revealed that, of the 1480 soil samples collected, 460 (31%) were positive for STH eggs. Toxocara sp. was the most prevalent (77%), followed by Ascaris sp. (11%), hookworms/strongyles/free-living nematodes (7%), and Trichuris sp. (5%). Some soil physicochemical parameters were also determined and associated with Toxocara eggs prevalence and density in soil. Results revealed that Toxocara sp. eggs were most prevalent in less acidic, relatively high temperature and high moisture soil conditions. They were also prevalent in sandy, silty, and loamy soil textures but less prevalent in clayey. No significant differences were found between depth 1 (0-5 cm) and depth 2 (6-10 cm). This study revealed that Toxocara sp. eggs are ubiquitous and the extent of contamination in soils from the selected towns of Laguna is relatively high. Hence, the data generated in this study can be used in promoting public awareness, particularly for pet owners and local health officials, for effective prevention and control of this parasitosis.