The joint association of air pollution and noise from road traffic with cardiovascular mortality in a cohort study.
OBJECTIVE
Associations between cardiovascular mortality and air pollution and noise together were investigated.


METHODS
Data from the ongoing Netherlands Cohort Study on Diet and Cancer (120,852 subjects; follow-up 1987-1996) were used. Cox proportional hazard analyses were conducted for the association between cardiovascular mortality and exposure to black smoke, traffic intensity on the nearest road and road traffic noise at the home address.


RESULTS
The correlations between traffic noise and background black smoke, and traffic intensity on the nearest road were moderate at 0.24 and 0.30, respectively. Traffic intensity was associated with cardiovascular mortality, with highest relative risk (95% confidence interval) for ischaemic heart disease (IHD) mortality being 1.11 (1.03 to 1.20) (increment 10,000 motor vehicles/24 h). Relative risks for black smoke concentrations were elevated for cerebrovascular (1.39 (0.99 to 1.94)) and heart failure mortality (1.75 (1.00 to 3.05)) (increment 10 microg/m(3)). These associations were insensitive to adjustment for traffic noise. There was an excess of cardiovascular mortality in the highest noise category (>65 dB(A)), with elevated risks for IHD (1.15 (0.86 to 1.53)) and heart failure mortality (1.99 (1.05 to 3.79)). After adjustment for black smoke and traffic intensity, noise risk reduced to unity for IHD mortality and was slightly reduced for heart failure mortality.


CONCLUSIONS
Associations between black smoke concentrations and traffic intensity on the nearest road with specific cardiovascular causes of death were not explained by traffic noise in this study.
Beelen
R
R
Institute for Risk Assessment Sciences, Division of Environmental Epidemiology, Utrecht University, PO Box 80178, 3508 TD Utrecht, The Netherlands.
Hoek
G
G
Houthuijs
D
D
van den Brandt
P A
PA
Goldbohm
R A
RA
Fischer
P
P
Schouten
L J
LJ
Armstrong
B
B
Brunekreef
B
B
D000368:Aged; D000393:Air Pollutants / Q000032:analysis / Q000633:toxicity*; D000397:Air Pollution / Q000009:adverse effects* / Q000032:analysis; D001145:Arrhythmias, Cardiac / Q000401:mortality; D002318:Cardiovascular Diseases / Q000401:mortality*; D002561:Cerebrovascular Disorders / Q000401:mortality; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006333:Heart Failure / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D018986:Motor Vehicles / Q000706:statistics & numerical data*; D017202:Myocardial Ischemia / Q000401:mortality; D009426:Netherlands / Q000453:epidemiology; D009624:Noise, Transportation / Q000009:adverse effects*; D016016:Proportional Hazards Models; D001335:Vehicle Emissions / Q000032:analysis / Q000633:toxicity
D000393:Air Pollutants; D001335:Vehicle Emissions