科学美国人 | 你知道我们每年会摄入多少塑料颗粒吗？

You Contain Multitudes of Microplastics 你的体内含有大量微塑料 Plastic is lightweight,malleable, durable. But it has also become so widespread that it’s ending up in a lot of unwanted places—including our own bodies. That’s according to a new study, which found that humans are consuming a shocking amount of so-called "microplastics." 塑料具有重量轻、可塑性强、经久耐用的特点。但它也因此变得特别普遍，总是出现在一些不该出现的地方——包括我们自己的体内。据一项新的研究显示，人类正在摄入大量所谓的“微塑料”。 "Microplastics, the kind of current working definition, is plastic less than five millimeters. So people commonly equate that to something like a grain of rice or asesameseed and down in terms of size class. I will say that most of the microplastics that people are interacting with are quite a bit smaller than the sesame seed size, which I think always kinds of shocks people when we start talking about the numbers because the kind of, you know, they can’t see a lot of these things, at least with the naked eye."Kieran Cox, a PhD candidate in marine biology at the University of Victoria in Canada and one of the authors of the study, which is in the journal Environmental Science & Technology. 该研究的作者之一、加拿大维多利亚大学海洋生物学博士基兰·考克斯说“根据当前的定义，微塑料指的是粒径小于5毫米的塑料。所以在大小上，人们通常把它等同于一粒米或一颗芝麻，甚至是比它们还要小的东西。而我要说的是，人类正在接触的大多数微塑料要比芝麻粒小得多。在我看来，当我们开始讨论这些数字时，人们常常会感到很震惊，因为很多这一类的东西人们是看不到的，至少用肉眼是看不到的。”这项研究被发表在《环境科学与技术》杂志上。 Microplastics come from numerous sources. They can be pieces shed from larger plastics or they may have been designed small to begin with. 微塑料的来源众多。它们可以是从较大的塑料上脱落下的碎片，也可以是一开始就被设计得很小的微粒。 For their study, Cox and his team pulled together past scientific literature that calculated the number of microplastics in things we commonly consume, such as in tap and bottled water, sugars, seafood—even in the air that we breathe. 在他们的研究中，考克斯和他的团队查阅了过去的科学文献，这些文献计算了我们常接触的物质中含有的微塑料数量，例如自来水、瓶装水、糖、海鲜，甚至是我们呼吸的空气。 This analysis helped them figure out the baseline amount of microplastics that people are consuming every year. They couldn’t include common foods like beef, poultry, vegetables and dairy in their analysis because data on them doesn’t exist yet. In fact, their study could only account for15 percent of people’scaloricintake. 这项分析帮助他们计算出了人们每年吸收的微塑料的基准数量。他们的分析无法将牛肉，家禽、蔬菜和乳制品等常见食品纳入其中，因为目前还没有这些产品的有关数据。事实上，他们的研究只囊括了人体热量摄入占比15％的物质。 Even missing the majority of what people swallow, the research revealed that—at the very least—humans appear to consume somewhere between 74,000 and 121,000 microplastic particles every year. 即使没有考虑到人们摄入的大部分物质，研究显示，人们每年至少摄入了7.4万到12.1万个微塑料颗粒。 That number goes up for people drinking bottled water rather than tap water. Now, is all this plastic ingestion safe? Scientists simply don’t know yet. 而且，对于饮用瓶装水而非自来水的人来说，摄入量将更大。那么，将这么多塑料摄入体内是否安全？科学家们尚不清楚。 This is kind of the first estimate of dose, you could say, right? So if you’re thinking in terms of toxicology and ecotoxicology, dose is a very important factor to think about, and so this kind of presents the first estimate, but it is very much anunderestimatebecause of what we don’t know. 你可以说，这只是对剂量的初步估计，对吧？因此，如果你从毒理学和生态毒理学的角度去考虑的话，剂量是一个非常重要的考虑因素，因此这只是初步估计，但是由于还有很多是我们不知道的，这个数字可能被严重低估了。 (全文共396个词，标红单词为考研重难点词汇) 重难点词汇：malleable['mælɪəbl] adj. 可锻的；可塑的；有延展性的；易适应的sesame['sɛsəmi] n. 芝麻，胡麻；通行证underestimate[ʌndərˈestɪmeɪt] vt. 低估；看轻 n. 低估