Researchers at the Israel Institute of Technology have found that children’s mattresses may represent a health hazard as they emit some dangerous pollutants at concerning levels overnight.
On measuring the emission rates of volatile organic compounds (VOCs), the team found that under sleeping conditions, certain polyurethane mattresses emit the gaseous compounds at levels that may be worrisome for children and infants.
However, the study did not provide any evidence of adverse health effects and the researchers say more studies are needed. Avoiding exposure to VOCs is impossible since they are found in hundreds of household items, including furniture, candles, paint, carpets, electronics, vinyl flooring, cosmetics and hairsprays. During sleep, poor bedroom ventilation and the proximity of the nose and mouth to the mattress means people probably inhale more of the compounds during this time than during other times of the day.
Exposure at high levels can be toxic and has been associated with health risks such as headaches, nausea, nerve problems, kidney damage and even cancer.
Measuring the VOCs Emitted by Mattresses
Now, Yael Dubowski and team have used eight types of children’s polyurethane mattresses to test the levels of VOCs they release and compare them to known risk levels for the compounds. They also measured how temperature, humidity and carbon dioxide concentration – all of which increase under sleeping conditions – may influence the level of several VOCs emitted. The researchers point out that children spend up to half their time in a sleeping environment.
The researchers placed pieces of the mattresses into continuous-flow chambers and took samples of exiting air to analyse levels of 18 VOCs using gas chromatography-mass spectrometry. They found that the mattresses released similar amounts of the compounds, with the exception of a flame-retardant compound that only one infant mattress emitted.
As reported in ACS' Environmental Science & Technology, the mattresses emitted higher levels of VOCs once they were heated to body temperature. A temperature that matched body heat was a major contributor to elevated VOC emission, compared with humidity and carbon dioxide.
The Risk Associated with these Exposure Levels
Since the researchers suspected that people may breathe in worrying levels of the compounds when their faces are next to the mattresses, they estimated the doses inhaled by adults, infants and children. They found that in most cases, exposure levels were well below risk levels for cancer and non-cancer related health problems. However, among infants and young children, the inhalation of some compounds such as acetaldehyde, formaldehyde and benzene reached what could be worrisome levels.
Another compound that represented a potential health risk was butylated hydroxytoluene, levels of which varied greatly between the different mattresses. In recent years, some studies have raised concern over whether butylated hydroxytoluene may have the potential to be carcinogenic, although this study found that levels were well below reference levels for cancer and non-cancer risk.
What are the Possible Adverse Health Outcomes?
The study did not investigate the possible adverse health outcomes for exposure to the VOCs, but multiple previous studies have implicated them in the onset of childhood asthma and the worsening of asthma in adults. The inhalation of VOCs is also known to be a potential eye, nose and throat irritant. It can also cause breathing problems.
However, Alastair Lewis, from the National Centre for Atmospheric Science, University of York, who was not involved in the research, says that the majority of VOCs are not damaging to health, although some research suggests that levels are increasing in air tight homes due to being trapped through a lack of ventilation: “If air gets trapped in a home, then there is some potential for even safe VOCs to be oxidised to more harmful products. Furnishings, such as sofas, carpets, beds and so on, can take longer to outgas, since VOCs are buried deeper in the product.”
Lewis says the thick polyurethane mattress used in the study is probably a worst-case example for testing VOCs due to its sponge-like composition and slow release of the compounds, but that even these mattresses lose their VOCs eventually. He also suggests that if a parent is concerned, they could opt for a cotton-, wool- or spring-based mattress, which would contain less VCOs.
Dubowski and team conclude by saying: “Exposure levels estimated for sleeping child/infant indicate that SME [sleeping microenvironment] can be a significant contributor to VOC exposure, yielding concerning exposure levels for few compounds.” They say further studies are needed to assess the potential health impact of long-term, low-level exposure to VOCs.
More about VOCs
- VOCs are gaseous compounds that are released by certain solid and liquid materials
- They include a range of chemicals, some of which have been associated with both short- and long-term adverse health effects
- The levels of many VOCs are often higher inside the home than outdoors – sometimes up to ten times higher
- The chemicals are widely used ingredients in household items and are released by thousands of products
- Fuels are made up of VOCs
- All of these products and substances release VOCs while they are being used and, to a certain, extent whilst they are stored
- The risk of adverse health effects varies significantly from VOCs that are highly toxic to those that are harmless
- The severity and nature of the adverse health effects depend on multiple factors including time and level of exposure
- Examples of harmful effects include headaches, poor coordination, liver and kidney damage, central nervous system damage, and eye, nose and throat irritation.
- Some VOCs are known to cause cancer in animals and humans
Volatile Organic Compound Emissions from Polyurethane Mattresses under Variable Environmental Conditions. Sabach, Sara, Merav, Bareket, and Oz, Kira. ACS Publications, 2019. https://doi.org/10.1021/acs.est.9b01557