SummaryBackground Long-term exposure to particulate matter air pollution has been associated with increased cardiopulmonary mortality in the USA. We aimed to assess the relation between traffic-related air pollution and mortality in participants of the Netherlands Cohort study on Diet and Cancer (NLCS), an ongoing study. MethodsWe investigated a random sample of 5000 people from the full cohort of the NLCS study (age 55-69 years) from 1986 to 1994. Long-term exposure to traffic-related air pollutants (black smoke and nitrogen dioxide) was estimated for the 1986 home address. Exposure was characterised with the measured regional and urban background concentration and an indicator variable for living near major roads. The association between exposure to air pollution and (cause specific) mortality was assessed with Cox's proportional hazards models, with adjustment for potential confounders.Findings 489 (11%) of 4492 people with data died during the follow-up period. Cardiopulmonary mortality was associated with living near a major road (relative risk 1·95, 95% CI 1·09-3·52) and, less consistently, with the estimated ambient background concentration (1·34, 0·68-2·64). The relative risk for living near a major road was 1·41 (0·94-2·12) for total deaths. Non-cardiopulmonary, non-lung cancer deaths were unrelated to air pollution (1·03, 0·54-1·96 for living near a major road).Interpretation Long-term exposure to traffic-related air pollution may shorten life expectancy.

Background: Current air quality standards for particulate matter (PM) use the PM mass concentration [PM with aerodynamic diameters ≤ 10 μm (PM10) or ≤ 2.5 μm (PM2.5)] as a metric. It has been suggested that particles from combustion sources are more relevant to human health than are particles from other sources, but the impact of policies directed at reducing PM from combustion processes is usually relatively small when effects are estimated for a reduction in the total mass concentration.Objectives: We evaluated the value of black carbon particles (BCP) as an additional indicator in air quality management.Methods: We performed a systematic review and meta-analysis of health effects of BCP compared with PM mass based on data from time-series studies and cohort studies that measured both exposures. We compared the potential health benefits of a hypothetical traffic abatement measure, using near-roadway concentration increments of BCP and PM2.5 based on data from prior studies.Results: Estimated health effects of a 1-μg/m3 increase in exposure were greater for BCP than for PM10 or PM2.5, but estimated effects of an interquartile range increase were similar. Two-pollutant models in time-series studies suggested that the effect of BCP was more robust than the effect of PM mass. The estimated increase in life expectancy associated with a hypothetical traffic abatement measure was four to nine times higher when expressed in BCP compared with an equivalent change in PM2.5 mass.Conclusion: BCP is a valuable additional air quality indicator to evaluate the health risks of air quality dominated by primary combustion particles.

Studies have suggested that children living close to busy roads may have impaired respiratory health. This study was designed to test the hypothesis that exposure to exhaust from heavy traffic in particular is related to childhood respiratory health. Children attending 24 schools located within 400 m from busy motorways were investigated. The motorways carried between 5,190 and 22,326 trucks per weekday and between 30,399 and 155,656 cars per day. Locations were chosen so that the correlation between truck and car traffic counts was low. Air pollution measurements were performed at the schools for 1 year. Respiratory symptoms were collected by parent-completed questionnaire. Sensitization to common allergens was measured by serum immunoglobulin E and skin prick tests. Bronchial hyperresponsiveness (BHR) was measured with a hypertonic saline challenge. Respiratory symptoms were increased near motorways with high truck but not high car traffic counts. They were also related to air pollutants that increased near motorways with high truck traffic counts. Lung function and BHR were not related to pollution. Sensitization to pollen increased in relation to truck but not car traffic counts. The relation between symptoms and measures of exposure to (truck) traffic-related air pollution were almost entirely restricted to children with BHR and/or sensitization to common allergens, indicating that these are a sensitive subgroup among all children for these effects.

As part of an international collaborative study on the impact of TrafficRelated Air Pollution on Childhood Asthma (TRAPCA), the health effects associated with long-term exposure to particles with a 50% cut-off aerodynamic diameter of 2.5 mm (PM2.5), PM2.5 absorbance, and nitrogen dioxide (NO 2 ) were analysed.The German part of the TRAPCA study used data from subpopulations of two ongoing birth cohort studies (German Infant Nutrition Intervention Programme (GINI) and Influences of Lifestyle Related Factors on the Human Immune System and Development of Allergies in Children (LISA)) based in the city of Munich. Geographic information systems (GIS)-based exposure modelling was used to estimate trafficrelated air pollutants at the birth addresses of 1,756 infants. Logistic regression was used to analyse possible health effects and potential confounding factors were adjusted for.The ranges in estimated exposures to PM2.5, PM2.5 absorbance, and NO 2 were 11.9-21.9 mg?m -3 , 1.38-4.39610 -5 m -1 , and 19.5-66.9 mg?m 3 , respectively. Significant associations between these pollutants and cough without infection (odds ratio (OR) (95% confidence interval (CI)): 1.34 (1.11-1.61), 1.32 (1.10-1.59), and 1.40 (1.12-1.75), respectively) and dry cough at night (OR (95% CI): 1.31 (1.07-1.60), 1.27 (1.04-1.55), and 1.36 (1.07-1.74), respectively) in the first year of life were found. In the second year of life, these effects were attenuated.There was some indication of an association between traffic-related air pollution and symptoms of cough. Due to the very young age of the infants, it was too early to draw definitive conclusions from this for the development of asthma.

We found evidence for an association of exposure to black smoke and traffic with lung cancer incidence in people who had never smoked. No associations were found for the full cohort, or for other categories of smoking.

Our objectives were to investigate the utility of the Hachinski Ischemic Score (HIS) in differentiating patients with pathologically verified Alzheimer's disease (AD), multi-infarct dementia (MID), and "mixed" (AD plus cerebrovascular disease) dementia, and to identify the specific items of the HIS that best discriminate those dementia subtypes. Investigators from six sites participated in a meta-analysis by contributing original clinical data, HIS, and pathologic diagnoses on 312 patients with dementia (AD, 191; MID, 80; and mixed, 41). Sensitivity and specificity of the HIS were calculated based on varied cutoffs using receiver-operator characteristic curves. Logistic regression analyses were performed to compare each pair of diagnostic groups to obtain the odds ratio (OR) for each HIS item. The mean HIS (+/- SD) was 5.4 +/- 4.5 and differed significantly among the groups (AD, 3.1 +/- 2.5; MID, 10.5 +/- 4.1; mixed, 7.7 +/- 4.3). Receiver-operator characteristic curves showed that the best cutoff was < or = 4 for AD and > or = 7 for MID, as originally proposed, with a sensitivity of 89.0% and a specificity of 89.3%. For the comparison of MID versus mixed the sensitivity was 93.1% and the specificity was 17.2%, whereas for AD versus mixed the sensitivity was 83.8% and the specificity was 29.4%. HIS items distinguishing MID from AD were stepwise deterioration (OR, 6.06), fluctuating course (OR, 7.60), hypertension (OR, 4.30), history of stroke (OR, 4.30), and focal neurologic symptoms (OR, 4.40). Only stepwise deterioration (OR, 3.97) and emotional incontinence (OR, 3.39) distinguished MID from mixed, and only fluctuating course (OR, 0.20) and history of stroke (OR, 0.08) distinguished AD from mixed. Our findings suggest that the HIS performed well in the differentiation between AD and MID, the purpose for which it was originally designed, but that the clinical diagnosis of mixed dementia remains difficult. Further prospective studies of the HIS should include additional clinical and neuroimaging variables to permit objective refinement of the scale and improve its ability to identify patients with mixed dementia.

Here we compare PM 2.5 (particles with aerodynamic diameter less than 2.5 mm) mass and filter absorbance measurements with elemental carbon (EC) concentrations measured in parallel at the same site as well as collocated PM 2.5 and PM 10 (particles with aerodynamic diameter less than 10 mm) mass and absorbance measurements. The data were collected within the Traffic-Related Air Pollution on Childhood Asthma (TRAPCA) study in Germany, The Netherlands and Sweden. The study was designed to assess the health impact of spatial contrasts in long-term average concentrations. The measurement sites were distributed between background and traffic locations. Annual EC and PM 2.5 absorbance measurements were at traffic sites on average 43-84% and 26-76% higher, respectively, compared to urban background sites. The contrast for PM 2.5 mass measurements was lower (8-35%). The smaller contrast observed for PM 2.5 mass in comparison with PM 2.5 absorbance and EC documents that PM 2.5 mass underestimates exposure contrasts related to motorized traffic emissions. The correlation between PM 10 and PM 2.5 was high, documenting that most of the spatial variation of PM 10 was because of PM 2.5 . The measurement of PM 2.5 absorbance was highly correlated with EC measurements and suggests that absorbance can be used as a simple, inexpensive and non-destructive method to estimate motorized traffic-related particulate air pollution. The EC/absorbance relation differed between countries and site type (background/traffic), supporting the need for site-specific calibrations of the simple absorbance method. While the ratio between PM 2.5 and PM 10 mass ranged from 0.54 to 0.68, the ratio of PM 2.5 absorbance and PM 10 absorbance was 0.96-0.97, indicating that PM 2.5 absorbance captures nearly all of the particle absorbance.

In a time series study, air pollution was associated with specific cardiovascular causes of death. Deaths due to heart failure (ICD-9 428), arrhythmia (ICD-9 427), cerebrovascular causes (ICD-9 430-436), and thrombocytic causes (ICD-9 415.1, 433-4, 444, 452-3) were more strongly associated with air pollution than cardiovascular deaths (ICD-9 390-448) in general. Excess relative risks were 2.5 to 4 times larger for these categories than for total cardiovascular disease mortality. Heart failure deaths, which made up 10% of all cardiovascular deaths, were found to be responsible for about 30% of the cardiovascular deaths related to particulate matter, SO2, CO, and NO2.