The common carp can help in detecting the magnitude of wastes in waterways, according to a study by a researcher at the University of the Philippines Los Baños (UPLB).
In a study conducted by Dr. Michelle Grace Paraso of the UPLB College of Veterinary Medicine, carp was found to have a potential use as a biomarker in detecting the level of pollutants in the country’s water resources.
The study evaluated carp as fish biomarker in determining the contamination of Laguna de Bay in four sites at Sta. Cruz and Paete, Laguna (East Bay) and Taguig City and Muntinlupa City (West Bay).
A biomarker is an organism with a particular substance or physical feature that may serve as indicator of some natural phenomenon like pollution and various biological pressures like infection and disease.
Paraso found that majority of the male carps in study site have shrunken testes compared with that of the normal male carp. Shrunken testes of a male carp indicate that the fish has been feminized. Such feminization shows that the carp was exposed to certain type of pollutant known as estrogen, among others.
According to the study, changes in the reproductive conditions of carp are influenced by several factors, such as food availability, water quality, and temperature.
Estrogenic contaminant or pollutant is estrogen produced through unnatural means. The contaminants developed from chemical components obtained in an environment and they cause reproductive impairment in water organisms such as fish.
Paraso is an expert from the Veterinary Medicine Division of the National Research Council of the Philippines of the Department of Science and Technology (NRCP-DOST), which funded the study. The study is relevant at this time when the government is pushing for a cleaner environment, especially in the coastal areas where many people live and obtain their livelihood, Paraso noted in her introduction to the study.