The burden of disease related to indoor air in the Netherlands: do different methods lead to different results?

BACKGROUND: Dutch policy makers needed a knowledge base for prioritising control of different indoor air pollutants. Several burden of disease (BoD) estimates were available, but it was not known if they could be applied to The Netherlands. OBJECTIVES: To quantify the BoD related to indoor air in The Netherlands, and to compare the outcomes with a previous study (EnVIE), which used a different BoD methodology. RESULTS: The largest BoD was attributable to environmental tobacco smoke. The next most important indoor air pollutants were radon and thoron from soils and building materials, followed by dampness and carbon monoxide (CO). Formaldehyde exposure did not contribute to the total BoD, according to our estimates. The EnVIE estimate was three times higher, and the most important indoor air pollutants by BoD were combustion products from outdoor sources, bioaerosols due to dampness and by outdoor sources, volatile organic compounds, radon from soils, pathogens and CO. The differences in estimates were primarily caused by the different selection or definition of substances in indoor air, rather than the differing BoD methodology. CONCLUSIONS: Indoor air exposure is associated with a considerable BoD in The Netherlands; approximately 1500 healthy life years per 1 million inhabitants are lost due to 1 year of exposure. The results from the different BoD studies examined here are difficult to compare--even the relative order of most important pollutants depends on choices and assumptions in the assessment. A careful evaluation of BoD estimates is required before they can be used in policy making.

Trends in aircraft noise annoyance: the role of study and sample characteristics.

Recently, it has been suggested that the annoyance of residents at a given aircraft noise exposure level increases over the years. The objective of the present study was to verify the hypothesized trend and to identify its possible causes. To this end, the large database used to establish earlier exposure-response relationships on aircraft noise was updated with original data from several recent surveys, yielding a database with data from 34 separate airports. Multilevel grouped regression was used to determine the annoyance response per airport, after which meta-regression was used to investigate whether study characteristics could explain the heterogeneity in annoyance response between airports. A significant increase over the years was observed in annoyance at a given level of aircraft noise exposure. Furthermore, the type of annoyance scale, the type of contact, and the response percentage were found to be sources of heterogeneity. Of these, only the scale factor could statistically account for the trend, although other findings rule it out as a satisfactory explanation. No evidence was found for increased self-reported noise sensitivity. The results are of importance to the applicability of current exposure-annoyance relationships for aircraft noise and provide a basis for decisions on whether these need to be updated.

Children's annoyance reactions to aircraft and road traffic noise.

Since annoyance reactions of children to environmental noise have rarely been investigated, no source specific exposure-response relations are available. The aim of this paper is to investigate children's reactions to aircraft and road traffic noise and to derive exposure-response relations. To this end, children's annoyance reactions to aircraft and road traffic noise in both the home and the school setting were investigated using the data gathered in a cross-sectional multicenter study, carried out among 2844 children (age 9-11 years) attending 89 primary schools around three European airports. An exposure-response relation was demonstrated between exposure to aircraft noise at school (L(Aeq,7-23 h)) and severe annoyance in children: after adjustment for confounders, the percentage severely annoyed children was predicted to increase from about 5.1% at 50 dB to about 12.1% at 60 dB. The findings were consistent across the three samples. Aircraft noise at home (L(Aeq,7-23 h)) demonstrated a similar relation with severe annoyance. Children attending schools with higher road traffic noise (L(Aeq,7-23 h)) were more annoyed. Although children were less annoyed at levels above 55 dB, the shapes of the exposure-response relations found among children were comparable to those found in their parents.

The association between noise exposure and blood pressure and ischemic heart disease: a meta-analysis.

It has been suggested that noise exposure is associated with blood pressure changes and ischemic heart disease risk, but epidemiologic evidence is still limited. Furthermore, most reviews investigating these relations were not carried out in a systematic way, which makes them more prone to bias. We conducted a meta-analysis of 43 epidemiologic studies published between 1970 and 1999 that investigate the relation between noise exposure (both occupational and community) and blood pressure and/or ischemic heart disease (International Classification of Diseases, Ninth Revision, codes 410-414). We studied a wide range of effects, from blood pressure changes to a myocardial infarction. With respect to the association between noise exposure and blood pressure, small blood pressure differences were evident. Our meta-analysis showed a significant association for both occupational noise exposure and air traffic noise exposure and hypertension: We estimated relative risks per 5 dB(A) noise increase of 1.14 (1.01-1.29) and 1.26 (1.14-1.39), respectively. Air traffic noise exposure was positively associated with the consultation of a general practitioner or specialist, the use of cardiovascular medicines, and angina pectoris. In cross-sectional studies, road traffic noise exposure increases the risk of myocardial infarction and total ischemic heart disease. Although we can conclude that noise exposure can contribute to the prevalence of cardiovascular disease, the evidence for a relation between noise exposure and ischemic heart disease is still inconclusive because of the limitations in exposure characterization, adjustment for important confounders, and the occurrence of publication bias.