Half of the 21 products put to the test by UFC Que-choisir were discovered to have potentially harmful ingredients, including lip balms from large cosmetic brands Garnier, La Roche Posay, Carmex, and Le Petit Marseillais.
The consumer group warned consumers to stay away from the balms which were found to have carcinogenic substances.
Others contained Mosh - mineral oil saturated hydrocarbons - which if swallowed, can make their way into the lymph nodes and liver and inflame them.
“The level of Mosh (mineral oil saturated hydrocarbons) in these lip balms is extremely undesirable, on account of their toxicity when they are ingested,” the report said.
But there is good news for anyone with chapped lips - the safest, most effective, and hydrating lip balm was found to the cheapest.
Lidl's “Cien” branded balm was the cheapest of the bunch priced at just 75 centimes.
“The enormous price differences aren't reflected in the results,” said representatives from UFC Que Choisir.
The lip balms consumers were urged to avoid were:
Macadamia lip balm from Yves Rocher
Trésors de miel nourishing lip balm from Garnier Ultra Doux
Original classic care from Labello
Classic moisturising lip balm from Carmex
Nultric transforming balm for dry lips from La Roche Posay
Homéostick from Boiron
Cold cream nourishing balm from Avène
Nutrition balm for dry lips from Le petit Marseillais
Hydrating lip balm from Aptonia
Hydrating lip balm from Uriage
Earlier this year, French authorities promised to investigate 1,000 cosmetic products found to contain illegal and undesirable substances after the consumer group published a similar report.
By Anna Schaverien