The Pollution Control Department has warned the public against eating fish caught in Song and Rangsit canals in Pathum Thani province and advised people to avoid contact with the canal water.
Large numbers of dead fish have been found floating in the two canals. The rotting fish have been emitting a foul smell, disturbing residents living nearby.
Surin Worakijthamrong, director-general of the Pollution Control Department, said today that officials collected water samples yesterday from five locations along Song Canal, near the Prueksa 44 housing estate, where large numbers of dead fish were found.
Tests showed that the water had a pH level of 7.17 and a dissolved oxygen (DO) level of 0 milligrams per litre (mg/L), indicating a complete lack of dissolved oxygen that could explain the fish deaths.
In Rangsit Canal, samples were collected from four locations. Tests showed pH levels ranging from 6.97 to 7.02 and DO levels ranging from 1.41 to 2.61 mg/L.
Laboratory tests are being conducted to analyse organic substances, bacteria, ammonia, nutrients and eight heavy metals.
Surin said, however, that no arsenic had been detected in the samples tested so far.
