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Used cot mattresses as potential reservoirs of bacterial infection: nutrient availability within polyurethane foam
1School of Allied Health Sciences, De Montfort University, The Gateway, Leicester, UK.
Insights
Proteins accumulate in exposed polyurethane (PU) foam of used baby mattresses, promoting bacterial growth. Waterproof covers reduce protein buildup, potentially lowering SIDS risk.
Area of Science:
- Microbiology
- Materials Science
- Public Health
Background:
- Bacterial contamination of polyurethane (PU) foam in used infant mattresses is a concern.
- Understanding nutrient sources for bacterial growth is crucial for infant health.
Purpose of the Study:
- To identify nutrient sources within PU foam of used cot mattresses that contribute to bacterial population density.
- To investigate the impact of mattress type and usage factors on bacterial growth.
Main Methods:
- Analysis of 30 used infant mattresses for bacteria degrading PU and soluble chemical components.
- Evaluation of mattress type (waterproof vs. exposed PU foam), age, and prior use.
- Correlation of protein levels with bacterial populations and Staphylococcus aureus growth.
Main Results:
- Significantly higher protein levels were found in mattresses with exposed PU foam.
- Protein levels positively correlated with culturable bacteria and Staphylococcus aureus growth.
- No significant associations were found for other measured parameters or mattress factors.
Conclusions:
- Exposed PU foam in infant mattresses facilitates protein accumulation, supporting bacterial growth.
- This provides a mechanism for increased bacteria in exposed PU foam.
- Waterproof covers may reduce SIDS risk by preventing protein accumulation.
Aim:
To evaluate possible source of nutrients for bacterial growth within polyurethane (PU) foam of used cot mattresses as determinants of bacterial population density.
Methods And Results:
Used infant mattresses (n = 30) were analysed for bacteria capable of degrading colloidal PU and for aqueous soluble chemical components (aromatic amines, ammonium ions, phosphates and protein). Mattress type (waterproof cover vs exposed PU foam at the infant-head region), mattress age and previous use by another child were evaluated as factors that could influence the measured parameters. The levels of protein extracted from PU foam were (i) significantly (P = 0.0019) higher for mattresses lacking a waterproof cover at the infant-head region and (ii) positively correlated with both culturable bacterial population densities of the PU foams and extent of growth of Staphylococcus aureus on aqueous leachates. No statistically significant (P > 0.05) associations between other measured parameters and mattress type/use factors were identified.
Conclusions:
Infant use of cot mattresses with exposed PU foam leads to accumulation of proteins within the PU, which can promote bacterial growth.
Significance And Impact Of The Study:
The study provides a mechanistic explanation for increased levels of bacteria associated with exposed PU of cot mattresses. In the context of the common bacterial toxins hypothesis for the sudden infant death syndrome (SIDS), this could explain the lowered risk of SIDS associated with use of a waterproof cover above the mattress.
