Countertops Product Guidance - Informed (2024)

Countertops considered in this guidance include porcelain slabs, quartz, cultured marble, solid surface, plastic laminate, natural stone, and ceramic tiles. Hazardous chemicals are common in many of these countertop materials and their required accessory products.

Hazards of accessory products such as substrates, adhesives, sealers, mortar, and grout should be factored into product selection. Some accessory products are required for use of the countertop materials, such as substrates for laminate counters. These substrates (e.g. particleboard, medium density fiberboard) commonly rely on formaldehyde-based binders that release formaldehyde, a carcinogen and asthmagen, into interior spaces over time.[1] If possible, specify laminate countertops with substrates made with a no added formaldehyde (NAF) resin.

Other accessory products that introduce additional hazards include natural stone sealers. Our research indicates that per- and polyfluorinated alkyl substances (PFAS) are common in stone sealers and that many natural stone products require sealing and resealing over time depending on stone porosity. PFAS are a class of chemicals that are a high priority to avoid because they can be toxic, persist in the environment, and build up in body tissues.[2] Certain grout sealers, such as those marketed as oil repelling, may also contain PFAS. Due to this, specifying countertops like ceramic tile that require grout and grout sealer is not recommended. See below for more complete guidance on hazards commonly present in countertop materials and accessory products as well as how to select healthier options.

In addition to hazards present during use, the production of countertop materials can have significant impacts on workers, nearby communities, and the broader environment through the release of hazardous chemicals. These impacts can occur at the facilities that make the countertops as well as those farther back in the supply chain. For example, if adequate controls are not in place, natural and engineered stone countertop fabrication and installation can expose workers to high levels of crystalline silica, which can cause silicosis (a lung disease).[3] Additionally, some countertop materials are made using plastic or other petroleum-derived materials. Oil and gas extraction and processing have significant impacts on surrounding communities.[4]

Here is some general guidance to use when choosing countertop materials:

• Specify mineral- or stone-based countertops that do not need to be sealed after installation. Good options include porcelain slabs, quartz, and some natural stone. Countertop sealers commonly contain PFAS, a class of chemicals, sometimes called “forever chemicals,” that are a high priority to avoid because they can be toxic, persist in the environment, and build up in body tissues.[2]
• Avoid countertops that are largely plastic. Examples such as cultured marble and solid surface are made from mineral fillers and plastic resins. Fossil fuel feedstocks are required for plastic production, and extraction and processing of these feedstocks have significant impacts on surrounding communities.[4]
• Avoid countertops that introduce formaldehyde, like laminate. If using laminate countertops, specify that the substrate be made with a no added formaldehyde (NAF) resin. Formaldehyde-based binders and adhesives can release formaldehyde, a carcinogen and asthmagen, into surrounding air after installation.[1] See the substrate guidance for additional details. Additionally, CDPH-certified laminate materials are preferred. CDPH emissions testing imposes limits on 35 specific VOCs, including formaldehyde. [5]
• Avoid countertops that may introduce lead. Ceramic glazes may contain lead compounds; tiles made in the USA typically avoid such lead glazes. Additionally, old cathode ray tubes (CRTs), which contain high concentrations of lead, may be incorporated as recycled content. Avoid countertops with non-specific post-consumer recycled content and ceramics that include CRT content. You can use this information request template to ask manufacturers about the origins and screening processes for recycled content.
• Avoid products marketed as antimicrobial. There remains no evidence that antimicrobial additives protect human health, and credible organizations such as the Centers for Disease Control and Prevention and Food and Drug Administration dissuade even hospitals from using products impregnated with antimicrobials.[6] Healthy Building Network advises that products advertised as antimicrobial be avoided whenever possible.[7]

Natural stone countertops that do not require sealing present few health hazards. The primary health hazard associated with natural stone, such as granite, is the sealer they typically require. Granite and other stone countertops may be sealed during their manufacture or after installation, and many manufacturers suggest that this sealer be re-applied periodically over the life of the countertop.

Sealer products are commonly based on fluoropolymer chemistry. Perfluorinated alkyl compounds (PFAS), which are persistent and bioaccumulate in the environment and have reproductive and developmental hazards, are the basis of this chemistry and are present as residuals in the sealer products.

Natural stone that is denser and/or less porous, such as soapstone and certain kinds of granite, may not require sealing.[8] Work with suppliers to ensure products do not require sealing and that they have not been factory-sealed. Sealing may take place at various points in the life of the product including manufacture, installation, and use. It is important to ensure that stone products remain unsealed, and therefore a healthy material option, throughout their lifecycle.

As with quartz countertops, dust generated from the fabrication and cutting of stone countertops can contain respirable crystalline silica, a carcinogen. If adequate controls are not in place, stone countertop fabrication and installation can expose workers to high levels of crystalline silica, which can cause silicosis (a lung disease).[3]

Porcelain is a ceramic material made primarily of natural components including clay, feldspar, and sand. Porcelain tiles are fired at higher temperatures for longer times than non-porcelain ceramic. As a result, they are denser and have lower water absorption. In recent years, several manufactures have begun offering large format porcelain slabs or panels that can be used for countertop applications. Their large size, up to roughly 10 feet in length, allows for fewer seams and therefore less grout and grout sealer.

Porcelain materials made without toxic glazes can be relatively low-impact materials for a countertop installation. Those made in the USA are typically free of lead compounds in their glazes.[9] Look for product literature that identifies where the porcelain slabs are made and what they are made of, including frits, glazes, and pigments.

Avoid products with non-specific post-consumer recycled content. These contents may be old cathode ray tubes (CRTs) from TV sets and computer monitors, which contain high concentrations of lead.

Porcelain slabs are further preferred within ceramic materials because they avoid grout lines and therefore avoid the need for sealing the grout, which can introduce hazardous “forever chemicals” or per- and polyfluorinated alkyl substances (PFAS).

Quartz or engineered stone countertops are made by combining granules of particulates - often quartz-containing rocks and minerals, but also glass, seashells, or other materials - with a small amount of polyester resin (a petroleum-based plastic) and pressing the mixture into a slab using a vacuum and high heat.

Polyester resins can contain trace amounts of cobalt, a carcinogen and reproductive toxicant. The chemical reaction of the polyester resin in countertop manufacturing uses styrene, a carcinogen and asthmagen.

Dust generated from the fabrication and cutting of quartz countertops can contain respirable crystalline silica, a carcinogen. If adequate controls are not in place, quartz countertop fabrication and installation can expose workers to high levels of crystalline silica, which can cause silicosis (a lung disease).[3]

Even when considering the hazards noted above, when compared to other countertop materials and the hazards associated with those materials throughout their life cycle, quartz countertops remain a relatively better choice.

Quartz countertops are non-porous so resist staining without requiring a sealer, which can introduce additional hazards.

Ceramic tiles are less preferred than porcelain slabs because they require grout and grout sealer, some of which can introduce hazardous “forever chemicals” or per- and polyfluorinated alkyl substances (PFAS). Ceramic tile countertops that do not use PFAS-based sealers are ranked yellow. Those using PFAS-based sealers are ranked red. Confirm sealing products do not contain PFAS.

Ceramic glazes may contain lead compounds; tiles made in the USA typically avoid such lead glazes. Look for tile product literature that identifies where the tiles are made and what they are made of, including frits, glazes, and pigments.

Avoid products with non-specific post-consumer recycled content. These contents may be old cathode ray tubes (CRTs) from TV sets and computer monitors, which contain high concentrations of lead.

Similar to quartz countertops, cultured marble is made from ground limestone and polyester resin. Cultured marble, however, typically contains more polyester resin (a petroleum-based plastic) and is cast into a mold of the desired shape. Pigments are swirled into the resin when it is wet to simulate the look of natural marble.

Polyester resins can contain trace amounts of cobalt, a carcinogen and reproductive toxicant. The chemical reaction of the polyester resin in countertop manufacturing uses styrene, a carcinogen and asthmagen.

Cultured marble countertops are non-porous and therefore do not require sealing. Sealers may introduce additional hazards.

Solid surface countertops are made from a slab of plastic, typically polymethylmethacrylate (PMMA). The countertops can be cut or formed into many different shapes and layouts, and if necessary, joined with a special adhesive to achieve a "seamless" look.

Manufacture of PMMA plastic releases methyl methacrylate, which is considered a respiratory sensitizer.

Because solid surface countertops are nonporous, they are stain-resistant and do not require sealing. Sealers may introduce additional hazards.

Laminates are composite products made from layers of paper impregnated with various formaldehyde-based resins, pressed together into a rigid sheet. Because it has no structural support, the sheet then needs to be adhered to a substrate, typically particle board or medium density fiberboard, to create the countertop surface.

These substrates commonly rely on formaldehyde-based binders that can release formaldehyde, a carcinogen and asthmagen, into interior spaces over time. If possible, specify laminate countertop substrates made with NAF (no added formaldehyde) resins.

Because the adhesive used to attach the laminate to the substrate can contain hazardous solvents, it is best to specify that P-Lam products be manufactured in the factory where exposure controls are more likely to be present rather than on-site. To help protect workers and those living near manufacturing facilities, specify that water-based laminating adhesives be used.

The primary health hazard associated with natural stone, such as granite, is the sealer they typically require. Granite and other stone countertops may be sealed during their manufacture or after installation Many manufacturers also suggest that this sealer be re-applied periodically over the life of the countertop.

Sealer products are commonly based on fluoropolymer chemistry. Perfluorinated alkyl compounds (PFAS), which are persistent and bioaccumulate in the environment and have reproductive and developmental hazards, are the basis of this chemistry and are present as residuals in the sealer products.

If granite or other natural stone is necessary for a building project, be sure to talk to suppliers about stone options that do not require sealing at any point.

As with quartz countertops, dust generated from the fabrication and cutting of stone countertops can contain respirable crystalline silica, a carcinogen. If adequate controls are not in place, stone countertop fabrication and installation can expose workers to high levels of crystalline silica, which can cause silicosis (a lung disease).[3]

While US manufacturers have eliminated toxic lead compounds from ceramic tile glazes, manufacturers outside the US continue to use them. Eighty percent of tiles sold in the US are imported, mainly from Europe and Asia, where leaded glazing remains common. Unless manufacturers specifically state otherwise, you should assume that glazed tiles not made in the USA contain lead, a PBT with cancer, developmental, and reproductive hazards. In addition, tiles with post-consumer recycled content from cathode ray tubes (CRTs) also contain lead from this recycled material.

When the location of manufacture can not be determined, the safest tile choices are unglazed tiles, or glazed tiles that are rated high for traffic abrasion (an abrasion resistance rating of IV or V according to ASTM C1027/ANSI A137.1, sometimes referred to as a PEI rating). The glazes of these tiles are less likely to wear down over time and introduce any lead that might be present into the living space.

Ceramic tiles require grout and grout sealer, some of which can introduce hazardous “forever chemicals” or per- and polyfluorinated alkyl substances (PFAS) into buildings. Ceramic tile countertops that do not use PFAS-based sealers are ranked yellow. Those using PFAS-based sealers are ranked red.