Some experts have found the chemicals used to deactivate UV rays (most commonly cinnamates, benzophenones and amino benzoic acid) react adversely with sunlight when they are absorbed, possibly causing DNA damage.

专家们发现，一些用于抵抗UV射线的化学物质（最常见的为肉桂酸、苯甲酮以及邻氨基苯甲酸）被皮肤吸收后，与日光产生不良反应，这很可能会造成DNA损伤。

Research by the University of California suggested that chemical filters in popular suncreams can trigger the kind of free-radical damage that could pre-empt skin cancer. The adverse effects seemed to happen only when UV rays hit sunscreen that had penetrated the skin.

加州大学的一项研究显示，时下大卖的防晒品中含有的化学过滤剂能够引起某种自由基伤害，大大增加了皮肤癌的发生几率。似乎只有当UV射线接触渗入皮肤的防晒剂时，才会引起这些不良反应。

Concern has also been raised about the chemical preservatives used in sunscreens, and other ingredients, seeping through the top layer of the skin.

防晒品中的化学防腐剂及一些渗入表皮层的其他成分也使得人们忧心忡忡。

A Swedish study found benzophenone-3 (or B-3), a popular suncream ingredient, in the urine of people who had applied no more than the recommended dose of suncream up to 48 hours before.

在瑞典的一项研究中，人们涂抹了少于推荐使用量的防晒品，而在48小时后研究者在参与者的尿液中发现了二苯甲酮-3，这是一种被普遍使用的防晒成分。

Should we be worried about such chemical infiltration of our bodies? 'Even if molecules are detected in urine, the levels are so low that they are not going to cause harm,' says Professor Brian Diffey, a leading expert in sun-protection research.

我们是否要担心这些化学成分在我们体内的沉积？防晒研究领域首席专家布莱恩•迪菲伊教授说：“尽管在参与者的尿液中发现了小分子的二苯甲酮-3，但剂量相当低不会对人体造成损害。”

What is less clear is whether the trend for using nanotechnology in sun products is bad news. In recent years, manufacturers have developed techniques that shrink particles of physical sunblock ingredients, such as titanium oxide and zinc, to a thousandth of the size of a human hair.

在防晒品中应用纳米技术，这种趋势是好还是坏？目前还尚无定论。近些年来，生产商们已研发出相应技术，将氧化钛以及氧化锌这些物理防晒成分的颗粒缩小到只有头发的千分之一。