Drink from plastic bottles can raise the body’s levels of a controversial "gender-bending" chemical by more than two thirds, acc

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问题     Drink from plastic bottles can raise the body’s levels of a controversial "gender-bending" chemical by more than two thirds, according to tests.
    Experts have been concerned about the possible health effects of bisphenol A(BPA)—an everyday chemical used in many plastic food and drink containers and tins as well as clear baby bottles—which is officially classified as toxic in some countries.
    A study found that participants who drank for a week from polycarbonate(聚碳酸酯)bottles showed a 69 percent increase in their urine(尿液)of BPA.
    Researchers did not say how much liquid was drunk per day. Researchers from Harvard School of Public Health studied 77 students, who had first undergone a seven-day "washout" phase in which they drank all cold beverages(饮料)from stainless steel bottles in order to minimise BPA exposure.
    They were then given two polycarbonate bottles and asked to drink all cold beverages from them during the next week. Previous studies have suggested that high levels of BPA consumption are linked to birth defects, growth problems and an increased risk of heart disease. In particular there are fears that heating the bottles, as parents would do when warming their baby’s milk, causes the chemical to leak in potentially dangerous quantities into the liquid contained within.
    " If you heat those bottles, as is the case with baby bottles, we would expect the levels to be considerably higher. This would be of concern since infants may be particularly susceptible to BPA’s hormone gland-disrupting(扰乱腺体激素分泌)potential. " said the senior author of the latest study, Karin B. Michels.
    Most adults carry BPA in their bodies but expert opinion on the risks is divided. The European Food Safety Authority believes that people naturally convert the chemical into less harmful substances in the body.
    Previous studies had found that BPA could leach(渗出)from polycarbonate bottles into their contents, but this study is the first to show the size of the corresponding increase in urinary BPA concentrations in humans.
    Harvard researcher Jenny Carwile said, " While previous studies have demonstrated that BPA is linked to adverse health effects, this study fills in a missing piece of the puzzle—whether or not polycarbonate plastic bottles are an important contributor to the amount of BPA in the body. "
How do experts evaluate the hazard that can be caused by BPA?

选项 A、They think it is so common in bodies that it isn’t hazardous material.
B、Different groups hold different viewpoints on this issue.
C、They believe it will be transformed into other safe materials.
D、They consider the amount of BPA in bodies decides its harmfulness.

答案B

解析 事实细节题。由定位句可知,对于BPA这种物质的危害性,专家的看法有分歧,B)与之相符,故为答案。联系上下文可知,原文主要在论证BPA可能对人体健康造成的影响,故排除A);由后文The European Food Safety Authority believes that people naturally convert the chemical into less harmful substances in the body.可知,认为人体可将BPA自动转化为危害较小的物质的是欧洲食品安全局,并不是所有专家都持有这样的观点,故排除C);D)中的“BPA在人体内的含量决定它的危害性”原文没有提及,故排除。
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