Safety of common skin whitener called into question

The Scientific Committee on Consumer Products (SCCP) investigated the ingredient at the request of one of the EU member states.

Kojic acid may pose risk to consumer health​

Their report concludes that kojic acid, at a maximum concentration of 1 per cent in skin care formulations, may pose a risk to the health of the consumer.

The ingredient is a fungal metabolite and works to inhibit tyrosinase – an enzyme that catalyzes the conversion of tyrosine to melanin.

By inhibiting tyrosinase, kojic acid decreases melanin synthesis therefore lightening skin colour.

The SCCP’s report looked at a number of scientific studies investigating, amongst other things, the dermal absorption, genotoxicity, carcinogenicity and reproductive toxicity of the compound.

According to the report, the ingredient is not genotoxic or carcinogenic to humans at likely exposures. Neither did the investigation show any reproductive toxicity of the compound in rats.

However, patch tests in human female volunteers compared the reaction to the ingredient of skin not usually exposed to kojic acid to skin regularly treated with the compound. This study concluded that skin regularly exposed to kojic acid became more sensitive to the compound, leading the SCCP to suggest it is a skin sensitizer in humans.

“Kojic acid has the potential to induce skin sensitisation,”​ concluded the SCCP.

Call for more data ​

Nevertheless, the report does state that if the industry were to submit more data the SCCP could refine this conclusion. In particular it calls for data on the kinetics of kojic acid after dermal application.

As kojic acid is one of the most common skin lightening ingredients it is likely that the industry will react quickly to this call for new data, in the hope that the new conclusion from the SCCP places the ingredient in a more favourable light.

A spokesperson from the UK trade body the CTPA confirmed that the industry is obviously confident of the safety of the widely used ingredient and that we can therefore expect a prompt reaction.

In addition, the SCCP has no regulatory power and it is the commission who decide whether or not to regulate regarding the SCCP opinions.

As the SCCP has called for more data the commission is unlikely to respond at this point, the CTPA explained.

The ingredient is not the only skin lightening compound whose safety has been questioned.

Hydroquinone was banned as a skin lightener in Europe, and its use limited to certain concentrations in the US, over fears that it could provoke severe skin irritation and patchy pigmentation.