Study suggests harmful properties of aluminium in sunscreens

The research, conducted by scientists at Keele University in the UK, measured the aluminium content of seven sunscreens, three of which listed aluminium as an ingredient.

All seven products were found to contain aluminium, although the quantity was higher in those where it was listed as an ingredient, which, in addition, highlights a secondary issue regarding reliable labelling of such products.

The study argues that if an individual was to follow WHO guidelines by applying 35 ml of product per sun screen application, a single application of one of the three sunscreens with aluminium as a listed ingredient would result in approximately 200 mg of aluminium being applied to the skin.

If the individual was to reapply sunscreen every two hours, as suggested by the WHO, a day at the beach would result in up to 1 g of aluminium salt being applied to the skin surface, the researchers claim.

The scientists, led by Dr Exley, cite previous studies concentrating on aluminium containing antiperspirants that suggest that aluminium salts do permeate the skin.

In addition, stating that "it is highly likely that the everyday use of sunscreens/sunblocks is a hitherto unrecognized contributor to the human body burden of this nonessential metal."

Exley suggests that the most immediate danger of an accumulation of aluminium in the skin is its pro-oxidant qualities - its ability to produce reactive oxygen species that may cause oxidative damage in the skin such as wrinkles, skin ageing and even cancer.

Recent research has suggested that some of the UV filters present in sunscreen can cause oxidative stress, particularly when the filter has remained in contact with the skin for more than an hour, and Exley speculates over the danger of having additional pro-oxidant compounds, such as aluminium salts, that could further exacerbate the problem.

This is not the first time that concerns have been raised over the possible negative consequences of regularly applying sunscreens to the skin.

The EWG has recently published a report claiming that 84 per cent of sunscreens either did not provide adequate protection against the sun's harmful rays or contained potentially harmful chemicals.

However many disagree strongly with these claims, suggesting that assertions over the danger of sunscreens are not scientifically reliable and may lead to consumers preferring to go unprotected - especially dangerous as skin cancer rates are still rising.

Earlier this week a leading US dermatologist, Marta VanBeek, disputed such claims pointing to the fact that groups suffering from skin conditions such a lupus or xeroderma pigmentosa, that have been using particularly large amounts of sunscreen over long periods of time, have not reported any significant side effects.