塑料的角色 在人类的健康方面的塑料不保健的使用和处理和它的效果已经变得关心的一个物质。当他们的色素包含高度有毒的重金属的时候 , 彩塑料是有害的。一些在塑料中被发现的有害金属是铜，领引，铬，钴，硒和镉。在大部分方面使塑料已经被法律上禁止的国家，彩色工业...

塑料 plastics 角色

The Problems of Plastic Bags 【参考范文】 Plastic bags have found their way into a wide area of everyday life. They are applied in big supermarkets, ordinary shops, small stores and street markets. People put in plastic bags everything they buy. They...

问题 They 塑料 bags plastic