The Six Chemical Classes Series: Flame Retardants

Types of Flame Retardants

A diverse range of flame retardants exists, encompassing numerous classes with varying chemical properties. Since the 1970s, one of these classes, organic retardants, particularly brominated varieties (BFRs), has been commonplace. Yet, due to emerging safety concerns, many of these ‘legacy’ BFRs are now banned or restricted, although they persist in the environment. Today, concerns about the environmental and health impacts have led to the introduction of new BFRs and the shift toward alternative retardants like organophosphorus and chlorinated compounds. A few examples include:

Brominated Flame Retardants (BFRs):

• Found in: Electronics, furniture and building materials.
• Health impacts: Linked to endocrine disruption and thyroid dysfunction. Despite replacements for older compounds, new versions also exhibit toxic effects on the endocrine system.

Hexabromocyclododecane (HBCD):

• Found in: Polystyrene foam building materials, primarily.
• Health impacts: Can alter immune and reproductive systems, has neurotoxic effects, and disrupts the endocrine system. It enters the environment during production and leaches from products, eventually entering the food supply.

Organophosphate Flame Retardants (OPFRs):

• Found in: Textiles, electronics and industrial materials.
• Health impacts: Studies suggest risks to bone and brain health, indicating potential widespread health concerns.

Polybrominated Diphenyl Ethers (PBDEs):

• Found in: Furniture and easily released into air and dust.
• Health impacts: Despite phaseouts beginning in 2004, PBDEs can persist in the environment for a long time without breaking down and have been linked to neurodevelopmental disorders in humans. Their continued presence in products means that exposure to them remains a concern.

Tetrabromobisphenol A (TBBPA):

• Found in: Plastic paints, synthetic textiles and electronic devices. It is also used as an additive in other flame retardants.
• Health impacts: Found to cause cancer in rats and mice, raising significant concerns about its safety for humans.

Common Routes of Exposure

Flame retardants are incorporated into a myriad of household and home decoration items to reduce flammability and adhere to safety standards. These substances are found in furniture and upholstery, such as sofas, headboards and mattresses as well as in home decor, including paints, wallpapers, drapery fabrics, carpets and blinds. Electronics and appliances, ranging from TVs and computers to kitchen gadgets, are also routes of exposure. Building materials such as insulation also contain flame retardants as do children’s products, including car seats, high chairs and toys, which are treated for added safety.

However, during normal usage, as well as throughout production, disposal, recycling and in the event of fires, these flame retardants may be released into our living environment. For instance, sitting on a treated sofa may expel air filled with chemical particles. Since they are not chemically bound to the materials to which they're added, they can easily migrate out of products, which then settle into household dust. This dust can escape outdoors or enter water and food systems. Many flame retardants, which are bioaccumulative and persistent, pose toxicity risks to wildlife and humans alike. Ongoing exposure occurs through skin contact with treated materials, inhalation of dust-borne particles and ingestion via the food chain. Legacy flame retardants – banned in many places but still found in the environment – continue to be detected at concerning levels, emphasizing the persistent nature of these substances and their long-term public health risks.

Health Concerns

In recent years, the potential health effects associated with the ubiquitous use of flame retardants in household items have become a hot topic. While retardants have been in use for decades, the long-term health implications of chronic exposure are still under investigation. Researchers are exploring potential links to various health issues, including disruptions in hormonal balance, reduced cognitive abilities and cancer.

Children are particularly vulnerable with their developing physiology and frequent interaction with flame-retardant-treated items such as toys and furniture. Research indicates that exposure during critical developmental stages may have lasting effects, prompting questions about the long-term impact on their health.

Environmental Impact

The environmental impact of flame retardants is a subject of ongoing research and has raised concerns. These substances can leach into water sources and soil, affecting not only human health but also aquatic ecosystems and wildlife. In response to these concerns, researchers and manufacturers are actively pursuing eco-friendly alternatives to traditional flame retardants. These alternatives are designed to provide effective fire protection while minimizing environmental harm. Promising developments include the use of bio-based materials, non-toxic chemicals and innovative technologies that degrade more easily in the environment.

What can you do in your home?

There are a number of things you can do to minimize your exposure to potentially harmful chemicals.

• Choose products with lower or non-toxic flame retardants when possible. For instance, when buying upholstered furniture look for a TB117-2013 label, stating the item does not contain flame retardants.
• Select natural fiber upholstery and textiles, such as wool, which is inherently flame-resistant and can pass domestic fire safety tests without the need for added chemicals.
• If possible, avoid buying furniture and baby products filled with polyurethane foam. Instead, opt for upholstery-fill alternatives such as sheep's wool, coir and jute, which are naturally fire-resistant and free from chemical flame retardants.
• Keep living spaces well-ventilated to reduce indoor air concentrations of flame retardants.
• Dust and clean regularly to minimize the accumulation of particles containing flame retardants. To reduce indoor dust levels vacuum with a HEPA filter, use a wet mop and dust with a damp cloth.
• Wash your hands before eating since hand-to-mouth contact can lead to flame retardant exposure – an especially important tip for children.

Regulatory Initiatives

Regulatory measures in various regions have been implemented to address the health and environmental impacts of flame retardants. These measures include restrictions on specific chemicals, updated testing standards and efforts to promote the use of safer alternatives.

At a policy level in the US there have been a number of bans on specific flame retardants. For example, polybrominated diphenyl ethers (PBDEs), which were commonly used in furniture and electronics, have faced restrictions in several countries, including the US, due to their persistence in the environment and potential health risks. Furthermore, the US updated its Toxic Substances Control Act in 2016, bringing about reforms that allow the Environmental Protection Agency (EPA) to evaluate and regulate chemicals, including flame retardants, more effectively. This includes conducting risk evaluations and taking necessary actions to mitigate unreasonable risks.

New Frontiers

Newer, less toxic flame retardant alternatives are being developed to meet safety standards without harmful chemicals. Innovations in eco-friendly fire resistance are advancing, indicating promising changes ahead. Although the subject may seem daunting, the concerted efforts of researchers, regulators and manufacturers toward safer options are reassuring. As consumers we can make a difference by choosing certified safe products, advocating for responsible chemical use and voicing our preferences to influence industry practices.

Photographer: Yennie/Adobe