Recently, researchers from the University of the Philippines-Diliman College of Science Institute of Chemistry (UPD-CSIC) who have been studying the rivers of Mega Manila have discovered the presence of EDCs, or endocrine-disrupting compounds.
EDCs are mixes of chemicals that can mimic hormones and thus adversely affect hormone regulation in the human body. Long-term exposure to these compounds can lead to a number of endocrine-related health issues, such as respiratory and neurodevelopmental problems, infertility, diabetes, obesity, and even prostate or breast cancer. Because of this, EDCs are considered water contaminants of emerging concern (CEC).
The study of Dr. Maria Pythias Espino and research assistants Kate Galera and Katrina Sta. Ana is the first to report on the occurrence and concentrations of EDCs in the Marikina, Pasig, Angat, and Pampanga rivers. This has provided useful baseline data for the Department of Science and Technology’s ongoing research program on “Removal of Excess Nitrogen and Endocrine Disruptors from Wastewater” (Renew).
“In the Philippines, it is important to know the presence and concentrations of EDCs in aquatic systems because many Filipinos depend on aquaculture for livelihood and subsistence,” said the researchers in their paper.
E1, or estrone, is a hormone that can induce endocrine-disrupting effects even at low concentrations of long-term exposure, such as fertility issues in aquatic organisms. It had been the only hormone detected to date in this study of the rivers, and its presence was attributed to municipal wastewater since this type of hormone can come from human and animal waste.
Industrial chemicals bisphenol A, nonylphenol, and octylphenol were also detected in the rivers. The researchers surmised that this was due to their extensive use in manufacturing various products such as detergents, textiles, plastics, and many more, but clarified that the concentrations are still below international guideline values.
The United States, Canada, and the European Union have guidelines for some EDCs in their environmental waters. The Philippines, however, does not have guideline values yet for the regulation of these compounds, nor the wastewater treatment facilities that would ensure the mitigation of CECs. The research team hopes these findings will hasten the formulation of national guidelines for the monitoring and control of these contaminants.
“Even in nanogram-per-liter to microgram-per-liter concentrations, these contaminants of emerging concern may have harmful effects on aquatic organisms and humans. The findings are critical evidence of contamination because there are no regulatory guidelines yet on these contaminants in the waterways and water systems,” the researchers explained, pointing out how the risks of EDCs lie particularly in their bioaccumulation and persistence.
“More cleanup efforts, effective regulations in wastewater treatment, and sustainable water resource management policies are needed to improve the water quality of the rivers in Mega Manila,” they advised. The Marikina, Pasig, Angat, and Pampanga rivers all drain into Manila Bay, affecting one of the country’s major socioeconomically important bodies of water.
The UP research has been made under the DOST project “Post-Wastewater Treatment Determination of Endocrine Disrupting Compounds for Interventions.” Water samples from the four rivers were processed by solid-phase extraction and analyzed by liquid chromatography with tandem mass spectrometry, a method of separating and identifying compounds in ultra-trace concentrations. (Maria Alexandra Marmol, UPD-CS Science Communications)