Toxic 'time bomb' threatens Mekong river basin

CHIANG SAEN, Thailand — Thai fisherman Somdet Singthong steered his metal skiff across the brown waters of the Mekong river, resigned to the pollution that has put his health and lifelong source of livelihood at risk. Doctors have found elevated levels of toxic arsenic in his fingernails and urine, with the heavy metal also detected in the river which millions of people in Southeast Asia depend on. Testing suggests the contamination, which experts and campaigners trace back to illegal mini