Plastic debris in the oceans is a major and growing problem in global environmental pollution. In this study, we conducted experiments to evaluate the toxicity of leachates from two single-use polyethylene plastic bags (PB1 and PB2) with the embryo and larvae of the commercial clam Meretrix meretrix.We speculate that compounds leaching from plastic bags are responsible for the observed toxicity.Therefore, leaching toxicity from plastic debris should be considered when assessing the risks of plastic pollution in the oceans.