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Do you know why does our skin gets tan after swimming in a pool?
Vidunenahawula Website (National Institute of Fundamental Studies)

Do you know why does our skin gets tan after swimming in a pool? Chlorine is a very strong chemical that can break down your skin’s protective barrier. When your skin is directly exposed to the sun, it triggers the production rate of melanin and exposure increases its rate of synthesis, which causes skin darkening. As chlorine water breaks your skin barrier you get irritated, tight and dry skin. This leads to sun burns and extreme tanning.