ScienceDaily (Oct. 7, 2011) —
A Californian-based study has looked in detail at air quality and the
impact of traffic-related air pollution on premature birth. Published in
BioMed Central's open access journal Environmental
Health, results from this study show that traffic-related air
pollution, especially polycyclic aromatic hydrocarbons (PAH), is
associated with up to a 30% increase in premature births, and that
seasonal changes and vicinity to the coast affected concentration of
toxic pollutants in the air.
The study, based at the University of California, looked at 100,000
births, within a five mile radius of air quality monitoring stations.
The study evaluated births spanning a 22 month period from June 2004,
and used information provided by the California Department of Health
about the births and the mothers, in addition to air pollution
information from monitoring stations which measure concentrations of
airborne toxic pollutants.
The researchers were able to analyse and compare exposures using
three different information sources: government "criteria pollutant"
monitoring stations (including carbon monoxide, nitrogen dioxide, ozone,
and fine particulate matter), a traffic pollution model (Land Use
Regression), and data about toxic chemicals collected by the South Coast
Air Quality Management District. Once integrated, these data provided a
new level of detail about the concentrations and location of individual
pollutants. All statistical models were adjusted for maternal age,
race/ethnicity, education and parity.
Some pollutants were area specific, relating to industry and
urbanization. However, overall exposure to critical pollutants such as
polycyclic aromatic hydrocarbons (PAH) resulted in up to a 30% increase
in the risk of premature birth. Other toxic substances, such as benzene
and fine particulate matter from diesel fumes were associated with a 10%
increase, while ammonium nitrate fine particles were associated with a
21% increase in premature birth. Concentrations of these pollutants were
higher in winter and lower in coastal areas, indicating that local
weather patterns played an important part in the dispersal of
pollutants.
Dr Beate Ritz said, "Air pollution is known to be associated with low
birth weight and premature birth. Our results show that traffic-related
PAH are of special concern as pollutants, and that PAH sources besides
traffic contributed to premature birth. The increase in premature birth
risk due to ammonium nitrate particles suggests secondary pollutants are
also negatively impacting the health of unborn babies. To reduce the
effects of these pollutants on public health, it is important that
accurate modeling of local and regional spatial and temporal air
pollution be incorporated into pollution policies."
Story Source:
The above story is reprinted (with editorial adaptations by ScienceDaily staff)
from materials provided by BioMed
Central, via EurekAlert!,
a service of AAAS.
Journal Reference:
- Michelle Wilhelm, Jo Kay Ghosh, Jason Su, Myles Cockburn, Michael
Jerrett, Beate Ritz. Traffic-related
air toxics and preterm birth: a population-based case-control study in
Los Angeles County, California. Environmental
Health, 2011; 10: 89 DOI: 10.1186/1476-069X-10-89
