Q: Is concrete sealer toxic?

A: Concrete sealers are available in three different forms: water based, solvent based and 100% actives/100% solids. The toxicity of a concrete sealer will depend on its chemical components. Generally speaking solvent based concrete sealers are going to be more toxic than water based concrete sealers. By viewing the SDS (Safety Data Sheet) you can view the hazardous statements and the precautionary statements associated with the product. Concrete sealers also contain volatile organic compounds (VOCs) which are emitted from liquid chemicals. Water based concrete sealers contain less VOC’s than solvent based sealers. VOC’s can be dangerous, have strong odors and result in adverse health effects.

That being said, solvent based concrete sealers tend to outperform and outlast water based concrete sealers. Water and solvents are used in concrete sealers to carry the active ingredients into the substrate and solvents are able to penetrate deeper and bond better. Solvent based concrete sealers can be more expensive than water based products. Now a days VOC regulations are set on a state level. Certain states are more strict with the amount of VOC’s allowed in a product for retail sale. For example certain areas of California have a VOC limit of 100 g/L. This makes it hard when shopping for a concrete sealer since manufacturers will not sell certain products to certain states. There are however, certain exempts solvents which are still allowed despite their VOC content.