A study involving 22 brands of lipstick found that 55per cent contained trace amounts of lead.
Underwriters Laboratories revealed that 12 of the lip products sampled tested positive for the toxic substance with the highest levels at 3.22 parts per million.
Commenting on the findings Dr Sean Palfrey, medical director for the Boston Lead Poisoning Prevention Program, warned that even low-level lead exposure poses a serious health risk and could affect mental health.
He told GMA, which commissioned the study: ‘What we know now is that even the lowest levels of lead can harm your IQ, your behavior, your ability to learn.’
Many anti-lead activists also stress the need to shield children and pregnant women.
Dr Halyna Breslawec, chief scientist for the Personal Care Products Council, added: ‘If you were serious about the public health aspects of lead poisoning you would not be looking at lipstick.
‘You would be looking at locations where children live. Do they live near hazardous waste dumps – are they chewing lead-containing paint fragments?’
Currently there are no standards set by the Food and Drug Administration limiting levels in lipstick and it is up to manufacturers to decide on the safety tests performed.
GMA declined to comment on which lipstick brands had been tested, but said that it had selected a range of colours from department stores and drugstores in the U.S.
Lead is not intentionally put in lipstick but many color additives are mineral-based and contain trace levels of lead naturally found in soil, water and air.
Janet Nudelman of the Campaign for Safe Cosmetics, highlighted: ‘Clearly the concerning part is that more than half of the lipsticks do contain lead, but half of them don’t, proving that it’s possible to manufacture a lipstick without lead.’
However the recent findings demonstrate that progress is being made.
A 2010 study by the FDA found the highest lead level in lipstick was 7 parts per million.
And another conducted earlier this year revealed that 400 shades of popular lipstick contained trace amounts of lead.
Lipsticks made by L’Oreal, Maybelline,Cover Girl, NARS and Stargazer landed in the top ten, prompting the FDA to evaluate whether it should recommend an upper limit.