But the researchers found extra ROS are generated only when the UV filters have penetrated into the skin and, at the same time, sunscreen has not been reapplied to prevent ultraviolet radiation from reaching these filters.

• 但研究者们发现，只有当遮光剂渗入皮下的同时，防晒霜并没起到阻挡紫外线进入的作用，并产生了额外的ros反应。