A man uses machinery as cleaning operation continues at Ao Prao Beach on Koh Samet, Rayong July 31, 2013. An oil spill that has blackened beaches at a Thai holiday island was having an extreme impact on tourism and could spread to the coast of the mainland and affect the fishing industry, officials and an environmental group said on Tuesday. REUTERS/Athit Perawongmetha (THAILAND - Tags: ENVIRONMENT DISASTER)