Air pollution and sudden infant death syndrome.
BACKGROUND
Sudden infant death syndrome (SIDS) affects approximately 1 in 1000 live births and is the most common cause of infant death after the perinatal period.


OBJECTIVE
To determine the influence of air pollution on the incidence of SIDS.


METHODS
Time-series analyses were performed to compare the daily mortality rates for SIDS and the daily air pollution concentrations in each of 12 Canadian cities during the period of 1984-1999. Serial autocorrelation was controlled for by city, and then the city-specific estimates were pooled. Increased daily rates of SIDS were associated with increases, on the previous day, in the levels of sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide but not ozone or fine particles measured every sixth day. Effects persisted despite adjustments for season alone or the combination of daily mean temperature, relative humidity, and changes in barometric pressure for NO2 and SO2 but not carbon monoxide.


RESULTS
Increases in both SO2 and NO2, equivalent to their interquartile ranges, were associated with a 17.72% increase in SIDS incidence.


CONCLUSIONS
Ambient SO2 and NO2 may be important risk factors for SIDS.
Dales
Robert
R
Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada.
Burnett
Richard T
RT
Smith-Doiron
Marc
M
Stieb
David M
DM
Brook
Jeffrey R
JR
D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D000397:Air Pollution / Q000009:adverse effects*; D002170:Canada / Q000453:epidemiology; D002248:Carbon Monoxide / Q000009:adverse effects / Q000032:analysis; D006801:Humans; D015994:Incidence; D007223:Infant; D009585:Nitrogen Dioxide / Q000009:adverse effects* / Q000032:analysis; D010126:Ozone / Q000009:adverse effects / Q000032:analysis; D012959:Socioeconomic Factors; D013398:Sudden Infant Death / Q000453:epidemiology / Q000209:etiology*; D013458:Sulfur Dioxide / Q000009:adverse effects* / Q000032:analysis
D000393:Air Pollutants; D013458:Sulfur Dioxide; D010126:Ozone; D002248:Carbon Monoxide; D009585:Nitrogen Dioxide