游泳时防晒霜或成毒药!
爱游泳的朋友们注意了,夏季外出游泳,不要再涂防晒霜了。最新研究表明,防晒霜中的化合物在与氯和紫外线发生反应时,会变成有毒物质。 Don't go swimming while wearing sunscreen - unless you want cancer. A compound used in the protective lotions turns toxic when it reacts with chlorine and ultraviolet rays, researchers found. Avobenzone is considered the most popular sun-blocker in the world due to its ability to absorb sunlight at different wave lengths - preventing skin damage. But Russian scientists suggest the UV-filtering compound forms cancer-causing toxins when exposed to a mixture of sun and chlorinated water. Aldehydes, phenols and chlorinated acetyl benzenes were created in experiments simulating swimmers wearing sunscreen. The latter two are considered extremely toxic and are strongly linked to deadly tumours and infertility, Lomonosov Moscow State University experts say. While a study earlier this year hinted that aldehydes can raise the risk of cancer as they interfere with the body's natural repair mechanism. 水中的转变 Lead author Dr Albert Lebedev said: 'On the basis of the experiments one could make a conclusion that a generally safe compound transforms in the water and forms more dangerous products. 'In spite of the fact that there are no precise toxicological profiles for the most established products, it's known that acetyl benzenes and phenols, especially chlorinated ones, are quite toxic. 'studying the products of transformation of any popular cosmetics is very important as very often they turn out to be much more toxic and dangerous than their predecessors. 'In principle, basing on such researches, one could obtain results, which could restrict or even put under a ban the usage of one or another product and preserve the health of millions of people.' 研究如何进行? The researchers used a scanning technique called chromatomass spectrometry to make their findings, published in Chemosphere. This technique, on laboratory cells, allows precise analysis of the most complex mixtures of chemical compounds. For the study, they simulated the real situation when a sunscreen, applied on the skin of a swimmer, comes into contact with pool water. The breakdown of avobenzone may take place right on the wet human skin, on which a sunscreen is spread. 数百万人使用 Sunscreen containing avobenzone are known to be applied by millions of people all over the world. Chemical UV filters like avobenzone absorb ultraviolet light due to the peculiarities of their structures. The substance in itself is safe. As well as being common in sunscreen, they are also used in some personal care products, such as makeup, moisturisers and lip balms. The researchers are now studying how avobenzone breaks down under conditions of chlorination and bromination of fresh and sea water. During chlorination or bromination of sea water the number of the breakdown products of avobenzone will be even wider. And if water contains copper salts - which are added into many swimming pools for getting nice light-blue colour - then bromoform is formed in large quantities. This substance could provoke dysfunctions of liver and kidneys - along with nervous system disorder, the experts implied. |