The Britain University of London cytology expert said that the skin exposes under the ultraviolet ray, easy to create the cell deoxyribonucleic acid (dna) damage, causes the skin color nigrescence.

• 英国伦敦大学细胞学专家说，皮肤暴露在紫外线下，容易造成细胞脱氧核糖核酸(dna)损坏，导致肤色变黑。