Abstract and Introduction
In their raw state, enzymes of bacterial/fungal origin cause allergic reactions in the lung. Proteolytic enzymes also cause irritation to skin, eyes and the respiratory tract. For 40years, encapsulated enzymes have been used worldwide in detergent products, especially laundry formulations, and have increasing importance due to biodegradability and functionality at low temperatures, offering environmental benefits. Uniquely to the U.K., for years it has been suggested that the inclusion of enzymes in such products leads to adverse skin reactions, including erythema, pruritus and exacerbation of eczema. In this review, we look at the facts, asking whether there is evidence that the hazards identified for enzymes translate into any risk for consumer health. By considering the actual exposures in consumer use and exaggerated product usage, it is concluded that the irritating and allergenic hazards of enzyme raw materials do not translate into a risk of skin reactions, either irritant or allergic. Investigations of numerous individuals with skin complaints attributed to laundry products demonstrate convincingly that enzymes were not responsible. Indeed, enzyme-containing laundry products have an extensive history of safe use. Thus, the supposed adverse effects of enzymes on skin seem to be a consequence of a mythology. The important practical lesson is that when primary or secondary care practitioners are presented with a skin complaint, it should not be dismissed as a result of using an enzyme-containing laundry product as the diagnosis will certainly lie elsewhere. Education for healthcare professionals could usefully be enhanced to take this on board.
Processes for the cleaning of clothes (laundry) have been with mankind for millennia, but the use of soaps and detergents represents only a relatively recent step. 'Sunlight' soap (a surfactant made by alkaline saponification of long-chain fats), usually recognized as one of the first to be subject to large-scale production and marketing, was first manufactured in the 1880s, and heralded the new way to wash laundry, first in the U.K. and then over the next decades, in many countries in the world. True soaps were then superseded by synthetic detergents (a range of types of surfactant often made from petrochemicals) during the mid-decades of the 20th century. However, the next big step change in cleaning came in the second half of that century with the introduction of proteolytic enzymes into laundry detergent products. Once the large-scale manufacture of enzymes which were stable in alkaline wash solutions and which were also resistant to the combination of relatively high temperature, the presence of oxidation systems and surfactants had been developed, this permitted the removal of a variety of stubborn stains at increasingly low temperatures. In the most recent decades, other enzymes classes have been incorporated, notably amylases and lipases, which further enhanced cleaning ability.
The manufacturers of these enzyme-containing laundry detergents contend that their products are safe for the consumer; indeed, they should not place them on the market if this were not the case. However, it has long been recognized that the enzymes used in these products have the potential to produce respiratory allergy during manufacture, thus requiring very strict exposure control for the workforce.[4,5,6] Additionally, proteolytic enzymes, the type most commonly used, have also been known to produce skin irritation, again occupationally. This is consistent with the observation of skin reactions to enzymes in other occupational settings, although some of these skin reactions may be urticarial as well as irritant. In the early period of marketing, some respiratory reactions were very occasionally seen in consumers. Particularly in the U.K., this background awareness of questions about allergy and irritation has translated into concern among some consumers and consumer groups that enzyme-containing detergents may be related to a variety of consumer skin complaints. Anecdotally at least, a similar view appears to be held by a variety of healthcare professionals. The purpose of this review is to investigate whether there is any truth behind these concerns. Are they factually based, or are they just fantasy?
The British Journal of Dermatology. 2008;158(6):1177-1181. © 2008 Blackwell Publishing
Cite this: Enzymes, Detergents and Skin: Facts and Fantasies - Medscape - Jun 01, 2008.