The Medical Sciences Department and Chiang Rai provincial administration have given an assurance that tap water and fish caught in the Kok, Sai and Ruak rivers, as well as vegetables grown in this northern province, are safe for consumption.
Chiang Rai Governor Charin Thongsuk told the media on Saturday that officials conducted tests on samples of water taken from the three rivers, tap water and fish in April and May and found the levels of arsenic to be lower within the acceptable standard.
The first test was conducted on April 8th. Samples of tap water taken from six districts of Chiang Rai were laboratory tested. The amount of arsenic they contained ranged between 0.001-0.009mg/litre, which is below the maximum safe level of 0.01mg/litre. Other heavy metals, such as lead, cadmium and manganese, were also below health-threatening levels.
The second test was conducted on May 2nd in Mae Sai and Chiang Saen districts and the amount of arsenic was still 0.001mg/litre.
Regular testing will be conducted until August, according to Dr. Watcharapong Kamla, deputy director-general of Medical Sciences Department.
He assured that the department’s methods for testing water and wastewater, using Atomic Absorption Spectroscopy (AAS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) techniques, which are internationally accepted, are extremely accurate, so the public can be sure that it is safe toconsume water, fish and vegetables.
Arsenic and other heavy metals discharged into rivers byunregulated gold mining operations in Shan state of Myanmar have been blamed for the contamination of the Kok and Sai rivers and other tributaries. Some fish caught in the rivers have been found to exhibit abnormalities.
