When we select raw ingredients for WEST SYSTEM epoxy products, we search for a balance between desired physical properties and lowest human and environmental health risks. Epoxy resins and hardeners are comprised of a number of chemical ingredients, of varying proportion and toxicity. Fortunately, they contain only a very small proportion of the more hazardous ingredients.
There is a safe exposure level for most substances. The more toxic the substance, the lower that level will be. Overexposure occurs when the safe exposure level is exceeded. When this happens, the substance can cause health problems.
Hazardous substances enter the body by skin absorption, inhalation or ingestion. The route for a particular substance depends on its physical characteristics and how it is normally used.
Epoxy Resins and Hardeners
The risk of exposure to resin, hardener, and mixed epoxy is greatest when they are liquid. As epoxy cures, the chemical ingredients react to form a non-hazardous solid. As it solidifies, epoxy and its components are less likely to enter the body.
Skin contact is the most common route of exposure to resins and hardeners. Even minor skin contact, if repeated often enough, can cause chronic health problems. In rare cases, with prolonged or repeated contact, the skin can absorb harmful epoxy ingredients.
Exposure by inhaling vapors is unlikely because epoxy products evaporate slowly. However, the risk increases when ventilation is inadequate or when the products are heated.
People rarely ingest epoxy, but it can happen when resin, hardener or mixed epoxy contaminates food, beverages or eating surfaces, and when good hygiene and clean-up practices are not followed.
Partially Cured Epoxy Dust
Sanding partially cured epoxy produces airborne dust, which increases your risk of exposure by skin contact, inhaling or ingesting. Although epoxy is firm enough to sand within two hours, it may not cure completely for up to two weeks. Until then, the dust can contain unreacted hazardous components. Do not overlook or underestimate this hazard.