Question

    Microplastics are everywhere in our environment. It's hardly surprising that the tiny fragments have also been found in humans. A new study shows that Americans are consuming as many as 121,000 particles each year.

Measuring 50 to 500 microns in length, microplastics come from a variety of sources, including large plastics that break down into smaller and smaller pieces. Therefore, much remains unknown about the common existence of these materials within the human body, as well as their impact on human health.

Hoping to fill in some of these gaps, a research team led by Kieran Cox, a PhD candidate at the University of Victoria, looked at 26 papers assessing the amount of microplastics in commonly consumed food items, among which are seafood, sugars, salts, honey, alcohol and water. The team also evaluated the potential consumption of microplastics through inhalation （吸入）using previously reported data on microplastic concentrations in the air and the Environmental Protection Agency's reported respiration rates. Based on these data, the researchers calculated that our annual consumption of microplastics via food and drink ranges from 39,000 to 52,000 particles. When microplastics taken in through inhalation are taken into account, the range jumps to between 74,000 and 121,000 particles per year.

The authors of the study found that people who drink exclusively from plastic water bottles absorb an additional 90,000 microplastics each year, compared to 4,000 among those who only consume tap water. "This shows that small decisions, over the course of a year, really matter and have an impact." Cox says. The new study, according to its authors, was the first to investigate "the accumulative human exposure" to microplastics. But in all likelihood, the research tells only a small part of the entire story. Collectively, the food and drink that the researchers analyzed represent 15 percent of Americans' caloric intake. The team could not account for food groups like fruits, vegetables and grains because there simply is not enough data on their microplastic content.

For those worried about microplastic consumption, cutting down bottled water is a good place to start. But to the heart of the problem, we have to stop producing and using so much plastic.

1.What makes it difficult to know microplastics commonly exist in the human body?

A.The quality. B.The quantity.

C.The shape. D.The size.

2.How did Kieran Cox's team calculate the potential consumption of microplastics?

A.By studying papers. B.By comparing the impacts.

C.By analyzing the data. D.By conducting experiments.

3.Which of the following is true according to the text?

A.Drinking less plastic bottled water helps to take in fewer microplastics.

B.The study is among the earliest to investigate human exposure to microplastics.

C.Cox's team gained comprehensive information of microplastics taken in by humans.

D.People consume 74,000 to 121,000 particles of microplastics per year from food and drink.

4.What is the best title for the text?

A.The Potential Problems of Microplastics

B.Microplastics Coming From Various Sources

C.Microplastics Found Within Human Bodies

D.The Impact of Microplastics on Human Health

Answer

1.D

2.C

3.A

4.C

【解析】

本文是一篇说明文，介绍了研究发现人体内含有大量的微塑料颗粒。

1.细节理解题。根据第二段中的“Measuring 50 to 500 microns in length, microplastics come from a variety of sources, including large plastics that break down into smaller and smaller pieces. Therefore, much remains unknown about the common existence of these materials within the human body”可知，微塑料颗粒的长度在50到500微米之间，有多种来源，包括可以分解成越来越小的碎片的较大塑料，因此，关于这些物质在人体的普遍存在还有很多未知之处，由此可知，微塑料颗粒的大小让我们很难知道它们普遍存在于人体中，故D项正确。

2.推理判断题。根据第三段中的“The team also evaluated the potential consumption of microplastics through inhalation （吸入）using previously reported data on microplastic concentrations in the air and the Environmental Protection Agency's reported respiration rates. Based on these data, the researchers calculated that our annual consumption of microplastics via food and drink ranges from 39,000 to 52,000 particles.”可知，基兰·考克斯的研究小组还利用先前报告的空气中微塑性物质浓度数据和环境保护署报告的呼吸速率，评估了吸入过程中微塑料的潜在消耗量，根据这些数据，研究人员计算出，我们通过食品和饮料每年消耗的微塑料颗粒从39000到52000不等，由此可知，基兰·考克斯的研究小组是通过分析数据来计算微塑料的潜在消耗量的，故C项正确。

3.细节理解题。根据第四段中的“The authors of the study found that people who drink exclusively from plastic water bottles absorb an additional 90,000 microplastics each year, compared to 4,000 among those who only consume tap water.”可知，这项研究的作者发现，那些只喝塑料瓶装水的人每年会摄入90000个微塑料颗粒，而那些只喝自来水的人每年摄入4000个微塑料颗粒，由此可知，少喝塑料瓶装水有助于减少微塑料的摄入，故A项正确。

4.主旨大意题。通读全文，特别是根据第一段“Microplastics are everywhere in our environment. It's hardly surprising that the tiny fragments have also been found in humans. A new study shows that Americans are consuming as many as 121,000 particles each year.”可知，微塑料在我们的环境中无处不在，在人类身上也发现这些微小的碎片并不奇怪，一项新的研究表明，美国人每年消耗的微塑料颗粒多达12.1万个，由此可知，本文主要介绍的是研究发现人体内含有大量的微塑料颗粒，故C项正确。