Preservatives in water-based paints can cause allergies and severe eczema with swelling, blisters and itching. An extensive study has shown that almost all water-based paints contain harmful preservatives.
In the 1970s and 1980s there were serious health problems associated with paint containing organic solvents. This led to a transition to water-based products, which were supposedly less harmful. In recent years, however, it has become clear these paints may also be harmful to health. An EU research study, in which Sweden also participated, was published in 2015 and showed that water-based paints contain large quantities of strongly or extremely strongly allergenic preservatives. A follow-up study in 2017 confirmed that finding. Of 60 water-based paints investigated, 94% contained harmful preservatives – and that was only isothiazolinones, one group of allergenic substances. Allergies caused by exposure to preservatives often take the form of eczema with swollen, red, rough skin. Eczema may sound like a relatively harmless complaint, but those affected by it will remain over-sensitive for the rest of their lives.
“If a person develops a contact allergy to these substances, the only way to avoid eczema is to stop exposure to the products,” says Marie-Louise Lind, an occupational hygienist at the skin allergy clinic at the Centre for Occupational and Environmental Medicine, Karolinska Institutet. She often meets patients with different types of contact allergies.
But avoiding these preservatives is easier said than done. In addition to paint, they are also used in a wide range of common hygiene products such as liquid soap, shampoo, skin cream and washing-up liquid. For those who have developed an allergy, extremely small quantities of the preservatives can cause the eczema to reappear.
Use protective gloves
Water-based paint is particularly harmful if it comes into direct contact with the skin, so gloves should always be worn when painting, preferably gauntlet models with a long wrist cover. There are also sleeves and aprons that protect the body against splashes.
“Plastic and rubber gloves resist water-based paint quite well and there are many different models to choose from,” says Marie-Louise Lind.
Exposure to harmful substances in water-based paint may take place through the air, either in the form of vapours from preservatives evaporating from a freshly painted surface which may continue over several weeks, or as dust created when a painted surface is sanded. How harmful a paint is depends on what kind of preservatives it contains, their concentration and how much exposure the skin receives. It can be difficult to see what the paint contains using safety data sheets, however. The list contents is rarely complete and as a user it is difficult to know with any real certainty what a product contains.
“If the amount of preservatives is below a certain level, the manufacturers are not obliged to declare the substance in the safety data sheet – but that does not mean that the paint is harmless, particularly for those who are sensitive to it,” says Marie-Louise Lind. Preservatives are added to water-based paint to increase its shelf life and prevent the growth of mould and bacteria.
Work Environment Authority calls for caution
Since the risks of water-based paints have become known, the Work Environment Authority, in cooperation with the Paint Industry, the Painters’ Union and the Paint and Adhesive Companies, has appealed to users of these products to protect their skin when they are painting.
The Work Environment Authority recommends a complete protective suit and access to eyewash when working with water-based paint. A long-sleeved shirt, long trousers and protective goggles or a visor should be used. Gloves should always be used, preferably those that are non-permeable to the paint. Disposable nitrile gloves or plastic gloves over cotton gloves work well. If any paint splashes on the skin, it is important to wash it away as soon as possible. If you try to wipe with a rag, there is a large risk that the chemicals will be rubbed into the skin.