Polycarbonate water bottles have received plenty of bad press for releasing potentially toxic compounds into unsuspecting drinkers, but there may be another culprit: everyday plastic packaging.
A German study of commercially-available bottled water found contamination by chemicals that mimic natural sex hormones. When the researchers raised snails in the water, they bred with extreme rapidity — a warning sign that the chemicals were active. Contamination levels were twice as high in brands packaged in plastic instead of glass, suggesting that plastic was the culprit.
Many additives used to make plastic more durable and elastic are known to have endocrine-disrupting effects in laboratory tests, and the average developed-world body is suffused with these so-called xenohormone residues. Research suggests that the consequences, though not fully understood, are real: fetal xenohormone exposures have been linked to reduced virility in boys and the early onset of puberty in girls. The effects may even linger in subsequent generations.
It wasn't known, however, whether xenohormones entered human bodies from food-packaging plastics in addition to other already-established sources, including polluted air, personal care products and food additives. The latest findings, published recently in Environmental Science and Pollution Research, suggest that packaging is at least partly responsible.
"Our findings provide first evidence for a broad contamination of mineral water with xenoestrogens," write the researchers. "We may have identified just the tip of the iceberg."
大量報道反映聚碳酸酯水瓶有可能釋放有毒化合物而消費者卻不知情。日常塑料包裝也可能是一大罪魁禍首。
德國的一項研究發現:市場上銷售的瓶裝水中含有類似天然性激素的化學污染物。研究人員在水中養蝸牛時發現蝸牛的繁殖速度極快——這是一個警告信號:該化學物質很活躍。 塑料瓶裝水中污染物的含量是玻璃瓶的兩倍,這表明塑料是罪魁禍首。
為了使塑料彈性更大、更耐久人們用了多種添加劑。測試表明,這些添加劑有干擾內分泌的效應。發達國家的人們體內充斥著這些被稱作是xenohormone激素的殘留物。 研究表明該殘留物造成的后果目前還不清楚,但實實在在存在:男孩陽萎增多和女孩青春期提前與胎兒感染xenohormone激素有關。該影響甚至會傳給后的。
然而,xenohormone激素除了經已有途徑(如空氣污染、個人保健品和食品添加劑)進入人體外是否經由食品包裝塑料進入人體,以前人們并不清楚。 最新發現表明塑料包裝要至少負部分責任。該研究報告發表在最近一期的《環境科學與污染研究》上。
研究人員說:礦泉水中普遍含有xenoestrogen激素殘留物,我們的發現為此提供了第一證據。我們發現的也許只是冰山的一角。”