Episode Details

The average liter of bottled water has nearly a quarter million invisible pieces of very small plastic known as nanoplastics, a recent study says. 

最近的一项研究表明，每升瓶装水中平均含有近 25 万个看不见的非常小的塑料，即纳米塑料。 

Researchers found the nanoplastics with a microscope using dual lasers. 

研究人员用双激光显微镜发现了纳米塑料。 

Scientists long figured there were lots of these very small plastic pieces. But until researchers at Columbia and Rutgers universities did their calculations, they never knew how many or what kind. 

科学家们长期以来一直认为有很多这样的非常小的塑料碎片。 但在哥伦比亚大学和罗格斯大学的研究人员进行计算之前，他们永远不知道有多少或是什么种类。 

Looking at five samples each of three common bottled water brands, researchers found particle levels ranged from 110,000 to 400,000 per liter. The average was around 240,000, the study said. The research appeared recently in the publication Proceedings of the National Academy of Sciences. 

研究人员对三个常见瓶装水品牌各五个样本进行了观察，发现颗粒物含量在每升 110,000 至 400,000 个之间。 研究称，平均人数约为 240,000 人。 这项研究最近发表在《美国国家科学院院刊》上。 

Nanoparticles are particles that are less than a micron in size. In comparison, a human hair is about 83 microns wide. 

纳米颗粒是尺寸小于一微米的颗粒。 相比之下，人类头发的宽度约为 83 微米。 

Previous studies have looked at slightly bigger microplastics that range from 5 millimeters, which could be seen by human eyes, to one micron. About 10 to 100 times more nanoplastics than microplastics were discovered in bottled water, the study found. 

之前的研究关注的是稍大的微塑料，范围从人眼可见的 5 毫米到 1 微米。 研究发现，瓶装水中发现的纳米塑料比微塑料多约 10 至 100 倍。

Much of the plastic seems to be coming from the bottle and the filtration system to