Lung function growth in children with long-term exposure to air pollutants in Mexico City.
BACKGROUND
Although short-term exposure to air pollution has been associated with acute, reversible lung function decrements, the impact of long-term exposure has not been well established.


OBJECTIVE
To evaluate the association between long-term exposure to ozone (O(3)), particulate matter less than 10 mum in diameter (PM(10)), and nitrogen dioxide (NO(2)) and lung function growth in Mexico City schoolchildren.


METHODS
A dynamic cohort of 3,170 children aged 8 years at baseline was followed from April 23, 1996, through May 19, 1999. The children attended 39 randomly selected elementary schools located near 10 air quality monitoring stations and were visited every 6 months. Statistical analyses were performed using general linear mixed models.


RESULTS
After adjusting for acute exposure and other potential confounding factors, deficits in FVC and FEV(1) growth over the 3-year follow-up period were significantly associated with exposure to O(3), PM(10), and NO(2). In multipollutant models, an interquartile range (IQR) increase in mean O(3) concentration (IQR, 11.3 ppb) was associated with an annual deficit in FEV(1) of 12 ml in girls and 4 ml in boys, an IQR range (IQR, 36.4 microg/m(3)) increase in PM(10) with an annual deficit in FEV(1) of 11 ml in girls and 15 ml in boys, and an IQR range (IQR, 12.0 ppb) increase in NO(2) with an annual deficit in FEV(1) of 30 ml in girls and 25 ml in boys.


CONCLUSIONS
We conclude that long-term exposure to O(3), PM(10), and NO(2) is associated with a deficit in FVC and FEV(1) growth among schoolchildren living in Mexico City.
Rojas-Martinez
Rosalba
R
Instituto Nacional de Salud Publica, 655 Avenida Universidad, Col. Santa Maria Ahuacatitlán, Cuernavaca, Morelos 62508, México.
Perez-Padilla
Rogelio
R
Olaiz-Fernandez
Gustavo
G
Mendoza-Alvarado
Laura
L
Moreno-Macias
Hortensia
H
Fortoul
Teresa
T
McDonnell
William
W
Loomis
Dana
D
Romieu
Isabelle
I
D000393:Air Pollutants / Q000009:adverse effects / Q000737:chemistry; D000397:Air Pollution / Q000009:adverse effects*; D002648:Child; D004781:Environmental Exposure / Q000009:adverse effects*; D004784:Environmental Monitoring; D005260:Female; D005500:Follow-Up Studies; D005540:Forced Expiratory Flow Rates / Q000502:physiology*; D005541:Forced Expiratory Volume / Q000502:physiology*; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008800:Mexico; D009585:Nitrogen Dioxide / Q000009:adverse effects / Q000032:analysis; D010126:Ozone / Q000009:adverse effects / Q000032:analysis; D010316:Particle Size; D011446:Prospective Studies
D000393:Air Pollutants; D010126:Ozone; D009585:Nitrogen Dioxide