Plastic is everywhere because plastic is an extremely useful material. It is cheap, strong and lightweight. What’s more, it can take on nearly any form or shape, from soft and stretchy (有弹性的) to hard and glasslike. Plastic, however, is far from perfect. It may even be bad for us. Studies now suggest that poisonous chemicals can get out of some types of plastic, get into our bodies, and cause a variety of health problems, including cancer, birth defects and attention deficit hyperactivity disorder (注意缺陷障碍). Two types of chemicals in particular have raised special concern lately. They are called phthalates (邻苯二甲酸盐) and Bisphenol-A (二酚基丙烷), BPA for short. Not all plastic products contain them. But the ones that do are surrounded by controversy (争议). That’s because experts disagree on how dangerous these chemicals are. Plastic is a single word, but plastic isn’t just one thing. What all plastics share in common are plasticizers -- special chemicals that allow the material to be changed into nearly any shape or texture. Plasticizers (塑化剂) are added to plastic during the manufacturing process. Phthalates and BPA are two types of plasticizers that work in different ways. Phthalates add softness to things like shampoo bottles, raincoats and rubber. They are also used in perfumes and makeup. BPA, on the other hand, gives a hard, clear, almost glasslike feel to products such as infant bottles. BPA also appears in food and soda cans, DVDs and other unexpected places. How do these chemicals get into us? When plastic is heated in the microwave or dishwasher, chewed on or scratched, the chemicals can seep (渗透) out of the plastic. Even though we can’t see them, we eat them, drink them and breathe them in. Scientists and parents are especially worried about young children, who tend to chew on everything, including plastic. Dozens of countries, including the European Union, Japan, Canada and Mexico have already banned phthalates from products made for children younger than three. California and Washington have done the same. And a number of other states are considering similar rules. As for BPA, Canada became the first country to ban the chemical from baby bottles. A dozen states are considering it. 小题1:What can we know about the plastic from the first paragraph?
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