According to research due to be released in the British Journal of Dermatology, biowashing detergents are no more harmful to people with eczema than their nonbio counterparts, despite a popular belief to the contrary.
Biological (bio) laundry detergents differ from nonbiological (nonbio) products in that they contain enzymes, which were first added to assist stain removal. In addition, their efficiency at low temperatures and their biodegradability offer environmental benefits.
However, for years it has been suggested that bio laundry detergents can trigger skin reactions, and that they should be avoided by people with eczema, as the enzymes might worsen the disorder. Interestingly, this line of thought is unique to the UK.
A team of researchers from Nottingham and London conducted a review of evidence, looking at both the actual exposures through use of the product, and at exaggerated levels that would not normally occur through normal use.
The researchers concluded that the possible irritant and allergic reactions that could be caused by enzyme raw materials do not translate into a risk of skin reactions when used in washing powders.
Dr Sarah Wakelin, Dermatologist at St Mary's Hospital in London and one of the researchers, said: "In terms of allergy, the evidence is consistent with what we know of the physiology of skin allergy.
"Substances must penetrate the outer skin barrier to reach the lower layers and do so in a sufficient quantity to activate the immune system in such a manner as to lead to an allergic response. By virtue of their size, enzymes are unlikely to penetrate the skin to any great degree. Also, enzymes in laundry products are encapsulated in robust, inert barrier. This means that actual skin exposure will be extremely low.
"Thus, the only occasions when there is likely to be some degree of exposure is either to the wash solution (when the enzyme encapsulate has dissolved) or from any enzyme residues on fabrics. As shown by various studies, contact with wash solutions does not lead either to irritation or to allergy, and residues on fabrics are also trivially low and do not give rise to any skin effects."
Dr Colin Holden, President of the British Association of Dermatologists said: "This study highlights that flare-ups of eczema should not just be written of as caused by washing powder. This serves as a reminder to medical professionals that an expert dermatologist should explore all the other potential causes, as bio detergents may well not be the culprit."