Upholstered Furniture: Emitting Indoor Air Pollutants?

The average person spends 90% of their time indoors, where the air quality is often 2-5 times more polluted than outdoor air. This is due to a variety of factors, including building materials, household cleaners, and furnishings, which emit volatile organic compounds (VOCs) and other chemicals into the air. Upholstered furniture is one such example, as it often contains polyurethane foam (PUF) with flame retardants, which have been linked to adverse health effects. Additionally, upholstered furniture can absorb dust, dirt, pet dander, and pollen, becoming a breeding ground for bacteria, allergens, and mold over time. These hidden pollutants are released back into the air when we sit or lie down on the furniture, affecting the quality of the air we breathe and potentially causing respiratory issues and allergic reactions.

Flame retardants in foam cushions

Flame retardants are not chemically bonded to the foam, allowing them to escape into the surrounding environment. They can be released into the air and settle as dust, providing a major route of exposure for people, especially children, who may touch contaminated surfaces and ingest the chemicals. The National Toxicology Program is currently assessing specific flame retardants, such as PentaBDE, for their carcinogenicity.

To reduce exposure to flame retardants in foam cushions, it is recommended to inspect the cushioning for damage and ensure that cushion covers are intact. Exposed foam helps flame retardant chemicals escape more quickly. It is also suggested to use a vacuum cleaner with a HEPA filter, as they are more efficient at trapping small particles and removing contaminants.

Additionally, consider choosing furniture that does not contain flame retardants or opting for second-hand furniture, as off-gassing diminishes over time. You can also look for certifications that indicate low-emission furniture, such as Greenguard or SCS Global Services. Airing out new furniture outdoors before bringing it inside can also help reduce the initial exposure to flame retardant chemicals.

By taking these precautions and choosing safer alternatives, individuals can reduce their exposure to flame retardants in foam cushions and mitigate the potential health risks associated with these indoor air pollutants.

Formaldehyde in plywood frames

Formaldehyde is a colourless and pungent-smelling gas with the chemical formula CH2O. It is composed of carbon, hydrogen, and oxygen atoms. Due to its highly reactive nature, it easily combines with other substances. Formaldehyde is a naturally occurring volatile organic compound (VOC) found in the air, trees, plants, fruits, and vegetables. Interestingly, humans and animals also produce very small amounts of formaldehyde.

Formaldehyde is widely used in various industries, including the production of plywood frames and bed frames. In plywood manufacturing, formaldehyde is used as an adhesive to bond timber sheets together, creating a popular building material known as plywood. This adhesive is typically a chemical resin called urea-formaldehyde or phenol-formaldehyde, which provides high tensile strength to the plywood. However, off-gassing of formaldehyde occurs from these adhesives, releasing it into the air.

The rate of formaldehyde release into the air is influenced by heat and humidity. Newly manufactured plywood tends to have higher formaldehyde emissions, which gradually decrease over a few weeks. By the time it reaches the supplier, formaldehyde emissions become close to negligible. To further reduce emissions, manufacturers apply phenolic coatings to plywood.

Formaldehyde exposure has been associated with short-term and long-term health issues. Short-term exposure to high levels of formaldehyde can cause sore throats, coughing, scratchy eyes, and nosebleeds. Long-term exposure has been linked to cancer, respiratory issues such as asthma, and neurological and reproductive problems. The United States Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC) classify formaldehyde as a "probable human carcinogen" and "carcinogenic to humans," respectively.

To reduce exposure to formaldehyde in plywood frames, individuals can take several measures. When purchasing plywood, look for formaldehyde-free options or choose exterior-grade plywood, as it off-gasses at a lower level. Additionally, consider buying used furniture, as off-gassing diminishes over time. If you can smell chemicals or experience irritation, remove the source. Ensure proper ventilation by opening doors and windows regularly, especially when introducing new furniture or during renovations.

Glues, dyes, and fabric treatments

In a study of white emulsion adhesive and silicone adhesive samples, a total of 21 volatile pollutants were detected. Xylene was the most concentrated compound from white emulsion adhesives, accounting for 45.51% of the total concentrations, while butanone oxime was the most concentrated compound in silicone adhesives, accounting for 69.86% of the total concentrations.

Textile dyes also have a significant impact on water bodies. They compromise the aesthetic quality of the water, increase biochemical and chemical oxygen demand, impair photosynthesis, inhibit plant growth, enter the food chain, and may promote toxicity, mutagenicity, and carcinogenicity. However, bioremediation of textile dyes is possible through the transformation or mineralization of these contaminants by the enzymatic action of plants, bacteria, extremophiles, and fungi.

Upholstered furniture is often manufactured with polyurethane foam (PUF) containing flame retardants (FRs) to prevent fires and meet flammability regulations. However, exposure to certain FRs and other chemicals has been linked to adverse health effects. Organophosphate FRs added to PUF, for example, were found to be released into the surrounding air and as dust.

Technologies exist to protect upholstered furniture from fire and chemical pollutant exposure, such as the use of barrier textiles between the cover fabric and the foam.

Dust, dirt, and pet dander

Pet dander, in particular, can be a significant source of indoor air pollution, especially for individuals with allergies. Pet dander consists of dried skin cells from pets, which are so light that they can float in the air before settling on surfaces. Pet hair can also carry dander, as it often holds minute particles of skin that are released at random times. As a result, pets with more hair or higher shedding rates, such as dogs, are more likely to spread dander. Cat allergies are twice as common as dog allergies, possibly due to a protein called Fel d 1 found on cats' skin, which is particularly allergenic due to its small size and sticky nature.

To reduce indoor air pollution from dust, dirt, and pet dander, regular cleaning is essential. This includes dusting, vacuuming with a HEPA filter, and washing bedding in hot water. Additionally, maintaining a relative humidity level of 30-50% in the home can help minimize the growth of dust mites and other biological contaminants.

Air purifiers can also be beneficial in reducing allergies and improving indoor air quality. The Mod+ air purifier, for example, is designed to remove 99.4% of all particles, including allergens such as pet dander and mould spores. Furthermore, when purchasing new furniture, it is essential to consider its potential impact on indoor air quality. Upholstered furniture, in particular, may contain chemicals such as flame retardants and volatile organic compounds (VOCs) that can be released into the air, potentially causing various health issues. To mitigate this, individuals can opt for used furniture, as off-gassing diminishes over time, or choose furniture with low-emission certifications.

Volatile organic compounds (VOCs)

Upholstered furniture is one such source of VOCs. The polyurethane foam (PUF) used in upholstered furniture often contains flame retardants, which can be released into the surrounding air and dust. In addition, the fabrics used in upholstered furniture may be treated with chemicals such as formaldehyde, which is a known carcinogen. Formaldehyde is also commonly used in plywood frames and composite wood furniture. Other sources of VOCs in upholstered furniture include glues, dyes, and fabric stain treatments.

The health effects of VOC exposure vary depending on the specific VOC and the level and duration of exposure. Short-term exposure to VOCs can cause eye, nose, and throat irritation, headaches, and dizziness. Prolonged or repeated exposure to high levels of VOCs may contribute to more serious health problems, especially for individuals with existing lung diseases. People with asthma or chronic obstructive pulmonary disease (COPD) may experience worsened symptoms when exposed to VOCs. VOCs have also been linked to neurological and reproductive issues, cancer, respiratory ailments, and heart conditions.

To reduce exposure to VOCs from upholstered furniture, it is recommended to buy used furniture, as off-gassing diminishes over time. It is also suggested to unwrap new furniture outdoors and let it sit for at least a week to air out before bringing it inside. Increasing ventilation by opening doors and windows and using fans can also help reduce VOC concentrations indoors.

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