Linda Birnbaum used to have a set of nonstick pans. Not anymore. She got rid of them.

Why？ Because Birnbaum—former director of the U.S. government’s National Institute of Environmental Health Science—became increasingly uncomfortable with an essential fact about that oh-so-easy-to-clean cookware： It’s very often made with PFAS， per- and polyfluoroalkyl（多氟烷基） substances， used to treat an array of products to make them resistant to heat， oil， stains， grease and water.

That’s pretty useful. But PFAS also belong to the set of human-made compounds known as “forever chemicals” that can linger endlessly in the environment and human body， sometimes with toxic（有毒的） effects. They can be found everywhBlylJmDx/sB2oLXew+9x+ZIVqbkkzFq/vqf8BNRreGY=ere—on the receipts from your drugstore， on your stain-resistant couch， in firefighting foams， in the water supply and， yes， in your kitchen.

That’s why Birnbaum’s pans went out the door.

“This huge class of chemicals is everywhere， in everything and in all of us，” she says. “I don’t use them anymore because I don’t want to be exposed to this stuff.”

PFAS and another forever chemical， BPA， have increasingly been the focus of concern among researchers and consumers in recent years. What are they？ What are the effects？

PFAS are a “huge family of chemicals，” says Tasha Stoiber， senior scientist for the Environmental Working Group. How huge？ Nobody seems to know—estimates range as high as 15，000 different compounds or more. Each contains a fluorine-carbon bond “that gives them unique properties of being stain-resistant， grease-resistant， water-resistant，” Stoiber says.

Officially， the U.S. Centers for Disease Control and Prevention says the human health effects of PFAS exposure are “uncertain” and require more research. But the agency also acknowledges that existing animal studies indicate the chemicals “may affect reproduction， thyroid（甲狀腺） function， the immune system and injure the liver.”

（材料來自Science網站，有刪改）

1. Why does the article start with Birnbaum’s story？

A. To strike a chord with readers.

B. To lead to the topic of the article.

C. To warn readers of nonstick pans.

D. To help her gain sympathy of readers.

2. What is the main idea of the third paragraph？

A. Where PFAS hide.

B. How PFAS affect people.

C. Why PFAS function well.

D. What benefits PFAS bring to us.

3. The benefits of using nonstick pans with PFAS should exclude _______.

A. no worry about water penetration

B. anti-high temperature protection

C. strong resistence to oil stains

D. the potential of health damage

4. According to the text， it has been proved that ________.

A. human health effects of PFAS exposure are certain

B. people in the future will quit the use of nonstick pans

C. the potential benefits of nonstick pans far exceed their dangers

D. uses of non-stick pans with PFAS run the risk of poisoning

1. B。解析：推理判斷題。材料第二段到最后一段反復提到PFAS——不粘鍋等廚具中含有的化學物質，以及其可能造成的傷害，由此推斷作者在第一段中提到關于扔掉不粘鍋的故事，是為了引出材料的話題，故選B。

2. A。解析：主旨大意題。材料第三段共有三句話，其中第二句中提到“PFAS屬于一組被稱為‘永久化學物質’的人造化合物，它們可以在環(huán)境和人體中長期殘留”，第三句中提到“它們無處不在”，由此A選項“PFAS藏在哪里”與材料內容相符，故選A。

3. D。解析：細節(jié)理解題。材料最后一段的最后一句中提到“現(xiàn)有的動物研究表明，這些化學物質‘可能影響生殖、甲狀腺功能和免疫系統(tǒng)，并損害肝臟’”，由此D選項“潛在的健康損害”與材料內容相符，故選D。

4. D。解析：細節(jié)理解題。材料第三段的第二句中提到“PFAS屬于一組被稱為‘永久化學物質’的人造化合物，它們可以在環(huán)境和人體中長期殘留，有時具有毒性作用”；材料最后一段提到“美國疾病控制和預防中心官方表示，接觸PFAS對人體健康的影響是‘不確定的’，需要更多的研究。但該機構也承認，現(xiàn)有的動物研究表明，這些化學物質‘可能影響生殖、甲狀腺功能和免疫系統(tǒng)，并損害肝臟’”。D選項“含有PFAS的不粘鍋的使用者要承擔中毒的風險”與材料內容相符，故選D。