Sunscreen ingredient Benzophenone, discovered to be linked to an increased risk of the painful gynaecological condition endometriosis.
Benzophenone is believed to mimic the female sex hormone oestrogen and has been linked to skin reactions in previous studies.
A new research published in the journal Environmental Science and Technology has stated that small amounts of ingredient can pass through the skin and be absorbed into the blood increasing the risk of endometriosis.
The condition, in which uterine tissue grows outside the womb, affects 1,500,000 women of reproductive age in Britain, or one in 10.
"This study is a salutary warning about this ingredient," the Daily Express quoted Professor Nick Lowe, a leading skin specialist, as saying.
"I wouldn't use this chemical on myself or my family and I am particularly worried about its use on children who are still developing," Dr Lowe, who works in London and California, added.
Professor John Hawk, a specialist on the effects of sunlight on the skin, at King's College London, said: "There are more modern and more reliable ingredients available, so I suggest it should be phased out.
US scientists analysed benzophenone levels in the urine of 625 women who had surgery for endometriosis.
They found high levels of a type of the chemical were linked with an increased risk of an endometriosis diagnosis.
Other research has shown that benzophenone, which is found in some cosmetics, can cause allergic reactions and absorbs through the skin in significant amounts.
Laboratory studies have linked it to adverse effects on the brain and nervous system, fertility and hormone problems.