The Consumer Council on Monday warned that some makeup bases can affect hormone levels, and people who are pregnant or are breastfeeding should avoid such products.

Among the 37 primers it reviewed, 17 of them that claimed to offer protection against ultraviolet rays contained potential endocrine disruptors.

The watchdog pointed out that aside from pregnant women and those who are breastfeeding, adolescents and children should also avoid using these products.

"[Potential endocrine disruptors] will affect your hormone levels, your sex hormones, maybe possibly it will impair your fertility," the council’s chief executive Gilly Wong said.

"And also for newborns, it may [cause] genital malformation; for the young adolescents, possibly premature puberty as well."

The watchdog found that only products that protect users from the sun made by Guerlain, Hourglass, and MAC are free from potential endocrine disruptors.

The council also noted that 15 products it examined contained BHT, a type of antioxidant that helps to improve product stability.

It said the substance could potentially lead to skin and eye irritation, according to studies conducted on animals.

Separately, the watchdog called on the public to be aware of alcohol concentrations and fragrance allergens in cosmetics, as they could lead to dryness and irritation.

Users should test products by applying them on the inner wrist, it added.