Past research has found that the ingredient benzophenone mimics the female sex hormone oestrogen and has been linked to skin reactions.
But the new study, published in the journal Environmental Science and Technology, claimed that small amounts of the chemical can pass through the skin and be absorbed into the blood where they are linked with an increased risk of endometriosis.
The condition, in which uterine tissue grows outside the womb, affects 1,500,000 women of reproductive age in the UK alone.
"This study is a salutary warning about this ingredient," Prof Nick Lowe, a leading skin specialist, was quoted as saying by the Daily Express.
Dr Lowe, who works in London and California, added: "I wouldn