SINGAPORE, Oct 27 — The effectiveness of a product's claims surely must be a good thing for the consumer, right?

For a woman in Singapore who became suspicious after her whitening cream for her underarms worked a little too well — it wasn't.

The cream produced effective results almost instantly and she alerted the Health Sciences Authority (HSA) about her concerns leading to the discovery various alarming ingredients in the cream, including mercury, a potent steroid, and a preservative banned from cosmetic skin creams.

After having bought the Q-nic Care Whitening Underarm Cream touted to help reduce body odour, whiten, and smoothen one's skin tone online, it was discovered that the product marketed as "safe, natural, non-toxic and harmless to your skin” was anything but as it was deemed unsafe, unnatural, toxic, and harmful to the skin.

Listings featuring the cream have been taken down from online retail platforms such as Carousell, Shopee, and Lazada, reported Mothership.

The cream was also found on the shelves of a shop at Lucky Plaza, which have been seized by HSA, while two sellers have been roped in to assist investigations.

Mercury is a forbidden ingredient in cosmetic products, as it may give rise to symptoms such as skin irritation and numbness.

Prolonged use of products containing mercury can also cause toxic effects to the kidneys and digestive and nervous systems, leading to organ damage.

Potent steroid found in the cream — betamethasone valerate — is typically prescribed for inflammatory conditions and should only be used under medical supervision.

Long-term, unsupervised use could cause hypersensitivity, skin thinning, and steroid withdrawal syndrome and may also bring about a host of major health problems like high blood pressure, cataracts, and muscular and bone disorders.