[20160811]IF10451_微珠：新出现的水质问题.pdf

https:/crsreports.congress.gov August 11, 2016Microbeads: An Emerging Water Quality IssueFor decades, water quality professionals have faced the challenge of controlling a variety of conventional and nonconventional pollutants (e.g., nutrients and suspended solids; oil and grease) and toxic chemical compounds that can harm aquatic life in lakes, streams, and coastal waters, as well as public health. Microplastics, plastic fragments that measure less than 5 millimeters (mm) in size (0.2 inches), are contaminants of recent and growing concern. Microplastic is ubiquitous and persistent in the environment. It has been reported in marine and coastal waters and many freshwater lakes and rivers worldwide, as well as on beaches and in sediments: a 2014 study estimated that 5.25 trillion plastic particles weighing nearly 270,000 tons are floating on seas globally. One source of microplastic pollution has received attention: microbeads, which are a subset of the contamination problem (probably less than 10% by volume). A number of companies are voluntarily removing microbeads from their consumer products, and nine states passed laws to ban manufacture and sale of products with microbeads. I