Inquinamento atmosferico e salute dei bambini

1. Inquinamento atmosferico e salute dei bambini Claudia Galassi

2. Inquinamento atmosferico e salute dei bambini Di cosa parliamo…. • Le conoscenze sugli effetti sulla salute dell’inquinamento atmosferico da traffico veicolare • Aspetti metodologici • Disegno degli studi • Esposizione • Outcomes

3. Inquinamento atmosferico e salute dei bambini Di cosa non parliamo…. • Effetti di alcune specifiche esposizioni (es. Piombo, Mercurio, inquinanti indoor) • Politiche per la salute e sviluppo sostenibile

4. From http://www.epa.gov/oar/oaqps/eog/course422/ap3.html

6. Particulate matter - definitions A complex mixture of airborne solid and liquid particles, including soot, organic material, sulfates, nitrates, other salts, metals, biological materials. • PM 10 -- inhalable particles • PM2.5 -- fine particles • PM10-PM2.5 -- coarse particles • PM 0.1 -- ultrafine particles

8. ACUTE health effects (e.g. asthma attacks, myocardial infarction, acute bronchitis, death..) • CHRONIC health effects (e.g. chronic bronchitis, lung cancer, anticipation of death...)

10. Aspetti metodologici

13. Weaknesses of experimental studies • a small number of, usually healthy, adult volunteer subjects (generalisability of results to the general population may be difficult) • “mix” of pollutants difficult to reproduce • chronic effects (ex. cancer) cannot be addressed

14. Types of studies for air pollution • Animal studies • Human studies • Experimental (chamber studies) • Epidemiological (or observational) • Cross-sectional • Case-control • Panel studies • Cohort • Time series

15. PM and progression of atherosclerosis • (rabbits model) Volume fraction of BrdU-positive AS nuclei in vessels (X10-2 %) n=9 n=5 n=9 n=6 Coronary arteries Aorta Suwa et al, 2002

16. Ambient Air Pollution and Atherosclerosis in Los AngelesKunzli et al, EHP 2005 (free access) carotid intima-media thickness (CIMT), a measure of subclinical atherosclerosis

17. Exposure Assessment • Individual exposure monitoring extremely expensive and complex

18. From: cleanairinitiative.org/portal/system/files/presentations/72526_apph.pdf

19. Exposure Assessment • Individual exposure monitoring extremely expensive and complex • Proxy of exposure (ex. Questionnaires)

21. Exposure Assessment 2. Generally from fixed site ambient monitors; the best options when large numbers exposed • Recent modelling techniques: LUR Models, Dispersion Models, both based on GIS

22. Types of studies for air pollution • Animal studies • Human studies • Experimental (chamber studies) • Epidemiological (or observational) • Cross-sectional • Case-control • Panel studies • Cohort • Time series

23. Med J Aust. 1998 Nov 2;169(9):459-63. Outdoor air pollution and children's respiratory symptoms in the steel cities of New South Wales. Lewis PR, Hensley MJ, Wlodarczyk J, Toneguzzi RC, Westley-Wise VJ, Dunn T, Calvert D. Open access

24. Objective: To investigate the relationship between outdoor air pollution and the respiratory health of children aged 8 to 10 years Methods: A cross-sectional survey (between October 1993 and December 1993) of children's health and home environment. Summary measures of particulate pollution [PM10] and SO2 were estimated for each area (using air quality monitoring station data from July 1993 to June 1994). Nine areas included.

25. Types of studies for air pollution • Animal studies • Human studies • Experimental (chamber studies) • Epidemiological (or observational) • Cross-sectional • Case-control • Panel studies • Cohort • Time series

26. Types of studies for air pollution • Animal studies • Human studies • Experimental (chamber studies) • Epidemiological (or observational) • Cross-sectional • Case-control • Panel studies • Cohort • Time series

27. Panel studies • Panel of subjects keeping daily diaries (ex. asthma diaries) (‘diary studies’) • Exposures • measured at the ecological level • measured individually • Outcomes • measured at the individual level (not necessarily with diaries)

28. Types of studies for air pollution • Animal studies • Human studies • Experimental (chamber studies) • Epidemiological (or observational) • Cross-sectional • Case-control • Panel studies • Cohort • Time series

29. Time Series Studies • Recently proposed (late 1980s) • Availability of advances in statistical techniques and in computing technology • Useful to investigate short term/acute effects of air pollution • Outcome and exposure are aggregated over 1 day

30. Mortality O3 November 17 2004

31. Time series studies • Uses routinely collected data for both exposure and outcome • Outcomes studied can be: mortality, hospitalisations, emergency department admissions, GP visits • Both exposure and outcome measured at the ecological level • Confounding: seasonal trends

33. Types of studies for air pollution • Animal studies • Human studies • Experimental (chamber studies) • Epidemiological (or observational) • Cross-sectional • Case-control • Panel studies • Cohort • Time series

34. Long-term health effects Chronic exposure studies evaluate health end pointsacross communities or neighborhoods with different levels of average pollution over longer time periods (usually 1 year or more). Pope CA, Environ Health Perspect 108(suppl 4):713-723 (2000).

35. Figure 3. Estimated Adjusted Mortality-Rate Ratios and Pollution Levels in the Six Cities. Mean values are shown for the measures of air pollution. P denotes Portage, Wisconsin; T Topeka, Kansas; W Watertown, Massachusetts; L St. Louis; H Harriman, Tennessee; and S Steubenville, Ohio.

36. Lung Cancer, Cardiopulmonary Mortality, and Long-term Exposure to Fine Particulate Air PollutionC. Arden Pope III, PhD; Richard T. Burnett, PhD; Michael J. Thun, MD; Eugenia E. Calle, PhD; Daniel Krewski, PhD; Kazuhiko Ito, PhD; George D. Thurston, ScD JAMA. 2002;287:1132-1141.

37. Methods • 500,000 subjects, as Part of Cancer Prevention II Study, enrolled in 1982 • Study population from 157 cities throughout the USA (157 data points of exposure) • Baseline questionnaire collected individual information (age, sex, weight, height, smoking history, etc) • Subjects’ risk factors linked to air pollution data and cause of death through to 1998

38. Birth cohorts https://www.progettoninfea.it/

39. Criteria for assessing causality of associations Hill (1965), Rothman (1986, 1998).

40. Effetti sulla salute dell’inquinamento atmosferico da traffico nei bambini

41. Effetti studiati: • Patologie respiratorie • Infezioni (alte /basse vie respiratorie) • Asma (aggravamento/insorgenza) • Esiti riproduttivi (nascite pre-termine) • Tumori infantili • Mortalità neonatale/infantile

42. Effetti respiratori acuti

45. Association of Low-Level Ozone and Fine Particles With Respiratory Symptoms in Children With Asthma JAMA. 2003;290(14):1859-1867. Design, Setting, and Participants  Daily respiratory symptoms and medication use were examined prospectively for 271 children younger than 12 years with physician-diagnosed, active asthma residing in southern New England. Main Outcome Measures  Respiratory symptoms and rescue medication use recorded on calendars by subjects' mothers. Results  Mean (SD) levels were 59 (19) ppb (1-hour average) and 51 (16) ppb (8-hour average) for ozone and 13 (8) µg/m3 for PM2.5. In copollutant models, ozone level but not PM2.5 was significantly associated with respiratory symptoms and rescue medication use among children using maintenance medication; a 50-ppb increase in 1-hour ozone was associated with increased likelihood of wheeze (by 35%) and chest tightness (by 47%). The highest levels of ozone (1-hour or 8-hour averages) were associated with increased shortness of breath and rescue medication use. No significant, exposure-dependent associations were observed for any outcome by any pollutant among children who did not use maintenance medication. Conclusion  Asthmatic children using maintenance medication are particularly vulnerable to ozone, controlling for exposure to fine particles, at levels below EPA standards.

49. Acta Paediatrica 2010

50. 2007 Associations are expressed as a percentage change (95% confidence interval) in the number of ER visits for an increase of 10 ug/m3 in NO2, at different lags (0–5),