Wildlife workers in Sri Lanka say two elephants were recently found dead after eating plastic waste in an open landfill.The problem is not new in the country.Conservationists and those who treat wildlife said about 20 elephants have died in the last eight years after eating plastic waste.The incidents happened at a landfill near a village in the Ampara District, about 210 kilometers east of the capital, Colombo.Nihal Pushpakumara is a veterinarian, a doctor for animals.He told The Associated Press that examinations of the dead animals showed they had swallowed large amounts of plastic that is not biodegradable.Biodegradable means a material can break down naturally in the environment.Different kinds of plastics were discovered inside the elephants along with other substances the animals could not digest, Pushpakumara said.Elephants are deeply respected in Sri Lanka.