January 17, 2014 00:00 By Janjira Pongrai
But levels in soil, water samples not high enough to kill animals, experts say
TEST RESULTS on soil and water samples from Prachuap Khiri Khan’s Kui Buri National Park, where 22 gaurs have died since December, showed higher-than-normal amounts of arsenic, but the levels were too mild to have caused the sudden deaths of the wild cattle, experts said.
Park officials now fear for the safety of a herd of 90 gaurs currently foraging in the north end of the park’s Kunchorn reforestation project, as two of its members are apparently sick. Ahead of today’s official announcement of the initial probe results, Pollution Control Department (PCD) director general Wichien Jungrungruang said yesterday that since December 26 the department had collected six soil samples, 15 silt samples and 10 water samples from around the Kunchorn project area.
It had also collected samples of other plants the cattle graze upon to determine the cause of the gaur deaths. The initial test results showed beyond-standard levels of arsenic in three samples.
A soil sample from a spot near where the first gaur was found showed an arsenic level of 29 milligrams per kilogram – compared with the safe level of 27mg/kg – while a water sample and a silt sample from a grass plot near the 17th gaur carcass also had slightly higher-than-standard arsenic levels, Wichien said. More details would be announced at a press conference today, he added.
However, the presence of arsenic near the carcasses couldn’t be confirmed as the cause of death, because soil naturally contains mild levels of the chemical. As a result, officials might have to collect more samples for clarity. Wichien said such slightly higher-than-standard levels of arsenic couldn’t suddenly kill gaurs – the level would have to be over 1,000mg/kg to be deadly. As some might argue the deaths could result from a prolonged exposure to the chemical, he said officials would have to collect blood samples from live gaurs for further testing.
Theerapat Prayoonsit, deputy director-general of the National Parks, Wildlife and Plant Conservation Department, said the two additional gaur carcasses found on Wednesday were a male over 15 years old and a skeleton with complete skull and horns. The latter animal was suspected to have died of natural causes two months ago.
Theerapat said caretaker Agriculture and Cooperatives Minister Yukol Limlaemthong had urged Livestock Development Department chief Tristsadee Chaosuancharoen to speed up test results and to send officials and veterinarians to help the park monitor wild cattle. One carcass was found in the north of the Kunchorn project area, where some 90 gaurs are now foraging for food, so officials would keep an eye on them, as two members were sick.