By Ellalun de Vera-Ruiz
The Pasig River Rehabilitation Commission (PRRC) has warned the public against eating fish caught in Pasig River due to high levels of pollutants in the waterbody.
This was PRRC’s disclosure after it conducted tests and tissue analysis on three-kilogram tilapia (Oreochromis niloticus), which had a length of 20.5 inches, that was caught in Estero de San Miguel last month.
It was found that the fish had high level of toxic heavy metal chromium, low concentration of fecal coliform, arsenic, cadmium, mercury, and lead.
“Since the tilapia caught in Estero de San Miguel at San Rafael Bridge is estimated to be more than two years old based on its length and weight, it is assumed to have accumulated relative amounts of contaminants depending on the existing conditions and water quality,” it said.
“Due to the presence of contaminants in the fishes collected, the PRRC would like to inform the public that deliberate and large consumption of the fishes in the Pasig River System may pose health risks in due time,” PRRC warned.
“It is highly advisable to prevent any conduct of contact recreational activities and consumption of freshwater organisms until further notice once sufficient and comprehensive scientific research has been made,” it added.
In February 2019, PRRC, through its Environmental Management Division, conducted a fish sampling collection and tissue analysis in four different areas based on reported abundance of fish caught in Pasig River.
The species of fish that were collected using fish nets were kanduli (Manila sea catfish), tilapia (Nile tilapia), banak (mullet), and bugaong (grunter). These were collected in Napindan Channel, Guadalupe Ferry Station, Santa Ana Ferry Station, and near Manila Bay.
Based on the tissue analysis results, the samples caught in all four stations have exceeded the permissible limit of fecal coliform.
PRRC pointed out that the widespread discharge of animal and/or human feces through runoff or ineffective sanitary facilities could be the cause of the elevated amounts in Guadalupe Ferry, while the presence of duck poultry in portions of Napindan Channel could have contributed to its high fecal coliform level.
Meanwhile, the fish samples in Guadalupe Ferry Station and Santa Ana Ferry Station have significant levels of lead at 0.8129 mg/kg and 0.664 mg/kg, respectively. The allowable lead content is only 0.2 mg/kg to 0.4 mg/kg, respectively.
In addition, the fish samples in Santa Ana Ferry Station manifested substantial mercury content at 0.65 mg/kg as compared to the standard 0.5 mg/kg to 1.00 mg/kg.
Meanwhile, the samples in all four stations passed the standard parameters for arsenic, cadmium, and hexavalent chromium.
The presence of fish in the Pasig River System has been verified by the 2009 study “Biodiversity Assessment of Pasig River and its Tributaries:Ecosystems Approach” by the Department of Environment and Natural Resources-Ecosystems Research and Development Bureau.
The study found that eight species of fish have already returned after a decade of rehabilitation efforts.
PRRC Executive Director Jose Antonio Goitia nevertheless said the return of fish in Pasig River was a positive development.
“We in the PRRC, are thankful to see the return of fishes, other aquatic life, and biodiversity in our beloved Pasig River. Their presence is a sign that the river has indeed improved after it was declared biologically dead in the 1990s,” Goitia said.
However, the agency reminded the public to “take utmost care in the consumption of fish caught in the Pasig River to avoid any negative effects on human health.”