Baby Mattresses Release Chemical Additives Into Sleeping Air

Chemical additives widely used in baby mattresses can enter the air immediately surrounding where young children sleep.

This exposure can build up over the many hours children spend resting, during a period in which their bodies are developing quickly.

Chemical additives in baby mattresses

New children’s mattresses available from major retailers contain chemical additives within both their foam cores and their outer covers.

Miriam L. Diamond, Ph.D., of the University of Toronto documented this pattern with her team, which tracked the release of these materials into nearby air in typical sleeping conditions.

The results indicate that exposure is not reliant on product damage, wear or age: newly purchased mattresses emit chemicals in normal use.

It is still unclear how far these subtle, recurring exposures add to overall risk. That makes it important to assess how emissions change when a child is lying on the mattress.

Heat and pressure increase emissions

Heat and body weight altered the way semi-volatile organic compounds - chemicals that can gradually escape products into air and dust - were released from mattresses.

Skin warmth of almost 37.8 degrees Celsius and pressure of roughly 7.7 kilograms raised emissions, as heat accelerated molecular movement while pressure forced trapped air outwards.

Under room conditions, researchers identified 12 target compounds; under simulated sleeping conditions, they detected 21 substances.

This rise is significant because families cannot detect these emissions by smell, and a lack of odour does not mean a product is cleaner.

A stationary sleeping microenvironment

A cot contains a small air pocket, and a child’s sleeping microenvironment - the air and surfaces directly nearby - remains particularly still.

Babies may spend as many as 18 hours daily on a mattress, while air just inches from the foam circulates more slowly than air elsewhere in the room.

The researchers compared air above the mattress with room air and found that elevated concentrations remained nearer to the bed.

Consequently, ventilating a room may not remove exposure during sleep, as the warmest air stays directly below the child.

Chemicals in mattress covers

Mattress covers contained several additives, including phthalates - plasticisers used to soften plastic in many consumer goods - alongside other chemical treatments.

As manufacturers do not chemically bind these ingredients into the material, they may transfer to dust and adhere to skin oils and textiles.

The researchers also identified UV filters, which are added to shield fabric dyes from sunlight, and one mattress exceeded a 0.1 percent regulatory limit.

Another five passed 0.1 percent thresholds applied to toys, illustrating how mattresses may fall outside regulations designed for smaller products.

Mattress foam and flame retardants

The foam also contained organophosphate esters, chemicals used as flame retardants or softeners, with some mattresses containing them at percentage levels.

Although these compounds can help foam resist smouldering, they may also leave the foam when heat and pressure compress its air pockets.

The team found tris(2-chloroethyl) phosphate in one mattress, despite Canada banning it in children’s foam products under Schedule 2.

This result indicates that prohibited additives may reach new products when manufacturers do not test and verify materials consistently.

How chemicals affect the body

The National Toxicology Program categorises di(2-ethylhexyl) phthalate as reasonably anticipated to be a human carcinogen.

Certain phthalates may disrupt the endocrine system, affecting hormones that direct growth and help determine developmental timing.

A 2013 review brought together evidence associating particular phthalate exposures with asthma, reproductive effects and changes in children’s behaviour.

These associations do not identify an individual mattress as the cause, but they reinforce calls to eliminate unnecessary additives.

Regulations lag behind products

In the United States, the Consumer Product Safety Commission limits several phthalates in children’s toys and child-care articles.

These limits centre on hand-to-mouth exposure because babies often mouth bedding and ingest dust that accumulates chemicals from soft materials.

Mattresses can nevertheless fall through regulatory gaps, as restrictions vary between product categories and manufacturers seldom reveal complete ingredient lists.

Where regulations fail to keep pace with design changes, enforcement becomes catch-up work that prioritises speed over safety.

The limitations of green labels

Buyers commonly seek green certifications, but the research found that comparable mattresses altered their formulations within only a few years.

If a company changes its cover material or foam supplier, its additive package can change too, even where the brand name does not.

In the study, six duplicate pairs purchased around two years apart had differing chemical profiles, occasionally in opposite directions.

Such turnover means that one-off testing and individual certifications are unreliable indicators, particularly for families purchasing on limited budgets.

Measures to reduce exposure

Parents cannot examine an absent ingredient label, but they can lower contact through dust management and the use of washable layers.

Regular wet cleaning, handwashing and laundering sheets may remove chemical-containing dust, because these substances adhere to particles.

“We were really shocked to find what was in the mattresses,” said Diamond. Shoppers are rarely given enough information to prevent that surprise.

What a safer baby mattress market requires

The results link mattress ingredients with the air children breathe while sleeping, where ordinary warmth and weight increase chemical emissions.

Stronger standards, more transparent labels and routine compliance tests would achieve more than consumer advice alone, particularly for lower-cost products.