Materials

Materials

Different building products and materials present a range of chemical hazards, some of which are explored below. 

Flooring

Flooring encompasses a wide range of product types – such as solid wood, laminate, carpet, ceramic tile, cork, linoleum, vinyl and concrete. 

These can present different chemical hazards.  For example, vinyl flooring can contain certain phthalates which are subject to concern regarding their endocrine-disrupting properties.  Whilst increased regulation is being seen in some regions for phthalates such as DEHP, DBP and BBP, this is not in place in all countries.

Chemicals in carpets have also seen increased scrutiny.  The Healthy Buildings Network published a 2017 report identifying 44 toxic substances, such as those in stain repellents and antimicrobials, that may be found in carpets.  

Paints and coatings

Some indoor and outdoor paints, preservatives and coatings have associated chemical hazards, affecting human health and causing environmental pollution:

Volatile Organic Compounds (VOCs) can cause respiratory problems for building occupants and painters. Some alkylphenol ethoxylates (APE) used as an emulsifier have been found to have endocrine disrupting effects.  Some wood preservatives designed for outdoor use are highly chemically intensive, from substances used to provide waterproofing and pesticidal functions. 

Concerns have been raised on the effects of preservative compounds such as pentachlorophenol and chromated copper arsenate (CCA), which are phased out in some global regions, but not all.

Materials and technologies for safer paints are now widely available, but these are not mainstream in every region, and regulation varies globally, resulting in chemically intensive and hazardous products remaining on some markets.

Resources provide further background on the main hotspots for paints, and showcases best practice products and policies.

• Paints may also contain phthalates for a plasticising effect, and PFAS may be added in some products to improve the flow and spread or waterproofing properties.
• Microplastic release from paints is the largest source of microplastic leakage into the ocean and waterways, estimated at 1.9 Mt/year, and ahead of sources such as textiles fibres and tyre dust.
• Lead in paint remains an issue in many regions - as of December 2021, still less than half of countries globally have lead paint laws.

Building plastics

A wide range of plastics are used in building and construction in piping, drainage, sheet and cladding, as well as in packaging. Plastics provide many useful functions in building, but they have become overused and have associated chemical hazards.

Plastics carry a range of environmental hotspots across their full lifecycle.  Hazards may be encountered in production from use of toxic precursor substances (such as the vinyl chloride monomer used in PVC production, a known carcinogen).  Some phthalates will endocrine-disrupting risks are still present in PVC materials, as well as stabilisers, some of which contain heavy metal compounds.

Hotspots also occur at end of life where this process is not effectively managed: chemical contamination may be passed on to recycled feedstock, and where not collected, plastics exhibit high persistence and low biodegradability in the environment.

Adhesives and sealants

These speciality building chemicals use a range of ingredients, with varying chemical safety profiles.

Adhesive types include epoxy, which can include alkylphenols and bisphenol-A, carrying endocrine disrupting hazards. Polyurethane-based adhesives, sealants and waterproofing are associated with risks from organotin compounds and the presence of isocyanates, which may cause respiratory problems.

Other sealants may emit high levels of VOCs, and phthalates may also be present in some products. PFAS chemicals, used to provide resistance to dirt, water and oil, have also been found in each of the above product types and are highly persistent and bioaccumulative.

Roofing

Roofing materials such as coatings and membranes are used to protect metal, tiled or asphalt, and are often required to resist weathering, repel dirt and provide durability. Some materials have been found to contain highly persistent PFAS, and some polymer-based membranes have been found to contain persistent, bioaccumulative and toxic halogenated flame retardants.

Other plastic based roofing materials (such as PVC and polycarbonate) may contain phthalates and bisphenol chemicals that carry endocrine disrupting risks, and have hazards in production from precursor substances (for example the vinyl chloride monomer used to make PVC is a known carcinogen).

Insulation

Insulation plays a vital role in improving the energy efficiency of buildings, but chemical hazards may be present in a variety of product types.

Whilst brominated flame retardants such as HBCD have been phased out by the Stockholm Convention, these compounds are still found in the environment due to their persistence, and in existing buildings such as those with older polystyrene insulation.

Spray foam insulation may contain isocyanates, and exposure through inhalation during curing can result in development of respiratory problems and illnesses. This may affect installers or DIY users working without proper personal protective equipment. 

Health and environmental hotspots may be encountered in both new materials as well as legacy insulation products, which may contain known hazardous materials such as asbestos.

Interior furniture and fittings

Wood-based interior furniture may use binders and glues that contain formaldehyde, which is linked to cancer in humans. Market development towards no-added formaldehyde glues is being seen, and many products now carry declarations and ecolabels to indicate that formaldehyde emissions from them are at a low level.

Fabric interior furniture may include flame retardants, which may not be communicated to the occupant. If furniture is not disposed of correctly at the end of life, release to the environment may take place, either from leaching in landfills, or emissions to air from incineration.