Epidemiologic studies on health effects of air pollution in

Masayuki Shima 島正之

Hyogo College of Medicine, Japan 兵庫医科大学

Outlines

 Air pollution and its health effects in the past  Pollution control and its effects on human health  Present status of air pollution in Japan  Traffic-related air pollution and its health effects  Epidemiologic study in Chiba Prefecture  Ongoing study by the Ministry of Environment (the SORA projects) Air Pollution in the past in Japan

Asthma

 Air pollution in the 1960s, due to complex in Yokkaichi, Japan

 Prevalence of bronchial asthma and chronic bronchitis increased among people living in the vicinity of the complex.

 In Japan, from around 1960, the concentrations of air pollutants increased in many industrial cities, and health effects of air pollution had became a major concern in the cities, including Tokyo, Kawasaki, Chiba, Fuji, , Amagasaki, Kobe.

Areas with high levels of air pollution in the 1960s and 1970s in Japan

Kurashiki, Tamano Bizen Kobe Amagasaki

Kita-Kyushu Omuta Tokyo Chiba Yokohama, Kawasaki Fuji Tokai, Nagoya Yokkaichi Osaka Concentrations of in Yokkaichi

Polluted area Non-polluted area

Petrochemical plant Concentrations of sulfur Yokkaichi dioxide（1964.11.24-27）

(Yoshida, et al. Arch Environ Health 13: 763-768, 1966)

Prevalence of chronic bronchitis and COPD among adults in Yokkaichi

Polluted area Non-polluted area

Chronic Bronchitis COPD Prevalence (%)

Isozu Shiohama Shiohama Yogo Tomisuhara Sakura (north) (south) Sulfur oxides (mg/day) Dust fall (ton/month) (Yoshida, et al. J Jpn Hyg, 22: 323-335, 1967) Asthma and sulfur dioxide in Yokkaichi

Relation between SO2 and Relation between asthma yearly accumulated prevalence attack and weekly average of asthma in 13 districts concentration of SO2

r = 0.88

Age group over 50 yr; At Isozu 13 patients April 1963 – March 1964 January to March 1963 (Yoshida, et al. Arch Environ Health 13: 763-768, 1966)

Concentrations of sulfur oxides in Fuji （1972）

Suruga Bay (Tani, et al. J Jpn Public Health, 22: 431-438, 1975） Chronic bronchitis and sulfur dioxide

Adjusted prevalence of chronic bronchitis among adults aged ≥ 40 years Prevalence (%) BMRC questionnaire

(Tani, et al. J Jpn Public Health, 22: 431-438, 1975） Sulfur oxides

Concentrations of sulfur oxides in Chiba 2 By PbO2 method, mg/100cm /day（1972）

Steel mill (Tokyo Bay) (Motomiya, et al. J Jpn Public Health, 22: 397-402, 1975） Relationship between prevalence of asthma and sulfur oxides Boys in 12 elementary schools（1972）

1971 1972 1971+1972 Prevalence of asthma Prevalence of asthma Prevalence of asthma

Sulfur oxides Sulfur oxides Sulfur oxides

(Motomiya, et al. J Jpn Public Health, 22: 397-402, 1975）

Change in concentrations of sulfur oxides in Yokkaichi Annual average concentrations measured by the PbO2 method

(Imai, et al. Arch Environ Health 41: 29-35, 1986) Sulfur oxides levels and mortality due to respiratory diseases in Yokkaichi

Age-adjusted mortality Top：Bronchial asthma Middle：Chronic bronchitis Bottom：Annual average concentration of sulfur oxides

(Imai, et al. Arch Environ Health 41: 29-35, 1986)

Concentrations of Sulfur Dioxide in Japan

(ppm) Annual average concentrations 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 1965 1970 1975 1980 1985 1990 1995 2000 2005 General environment Roadside Concentrations of Nitrogen Dioxide in Japan Annual average concentrations (ppm) 0.06

0.05

0.04

0.03

0.02

0.01

0 1970 1975 1980 1985 1990 1995 2000 2005

General environment Roadside

Concentrations of Suspended Particulate Matter (≤10m in diameter) in Japan

(mg/m3) Annual average concentrations 0.10

0.08

0.06

0.04

0.02

0.00 1975 1980 1985 1990 1995 2000 2005 General environment Roadside Changes in Automobile Ownership

(10,000 Vehicles) (Number of Vehicles)

Others (Buses, etc)

Trucks

Passenger Automobiles

(Fiscal Year)

Changes in the problems of Air Pollution

 Industrial air pollution (factories, etc.) → Urban/Domestic air pollution（vehicles, etc.）

 Gaseous pollutants → Particulate matters

 Fine particles, Diesel exhaust particles, etc.

 Uncontrolled toxic air pollutants

 High concentrations → Relatively low concentrations

 Wide areas around factories → Regional areas adjacent to major roads Prevalence of bronchial asthma among Japanese children (%) 5.0

4.0

3.0

2.0

1.0

0.0 1987 1990 1993 1996 1999 2002 2005 2008 Preschool Elementary school Junior high school High school (School Health Survey in Japan)

Health effects of automobile exhaust Epidemiologic study in Chiba Prefecture (1985～2000)

 Study subjects  Children in 10 elementary schools (about 6,000) ● ○●

● Schools are located in urban areas, ● and their school districts are ●● intersected by major trunk roads. ●○ Schools are in rural areas, without ●● major roads or factories.  Questionnaire for respiratory symptoms ●○ ○●  Pulmonary function tests  Blood sampling for allergic and inflammatory tests ○●  Measurements of indoor environments Prevalence of asthma

12

p = 0.026 p = 0.022† p = 0.043† 10

8

6

Prevalence (%) 4

2

0 1992 1993 1994 1995 1992 1993 1994 1995 Males Females

0-49 m ≥ 50 m Rural areas (Shima, et al. J Epidemiol, 13: 108-119, 2003)

Incidence of asthma 1992～1995

p = 0.013† 0-49 m 8 ≥ 50 m Rural areas

6 p = 0.158†

4 Incidence (%) Incidence 2

0 Males Females (Shima, et al. J Epidemiol, 13: 108-119, 2003) Prevalence and incidence of wheeze

Prevalence of wheeze Incidence of wheeze

12 8 0-49 m p = 0.347† 0-49 m p = 0.038† ≥ 50 m ≥ 50 m 10 Rural areas Rural areas 6 8

6 4 p = 0.893 Prevalence (%)

4 (%) Incidence

2 2

0 1992 1995 1992 1995 0 Males Females Males Females ³ (Shima, et al. J Epidemiol, 13: 108-119, 2003)

Odds ratios for various factors on the incidence of asthma Adjusted for all variables using logistic regression model Males Females Areas 0-50 m 3.77 4.03 > 50 m 1.99 1.74 Rural areas 1.00 1.00 School grade, 1 grade increase 1.13 0.94 History of allergic diseases 2.95 6.03 Respiratory diseases before 2 yr 1.85 2.08 Breast feeding in infancy 1.42 0.60 Parental history of allergic diseases 2.82 1.20 Maternal smoking habits 1.74 2.15 House of steel or reinforced concrete 0.92 0.40 Use of unvented heaters in winter 1.47 0.77 (Shima, et al. J Epidemiol, 13: 108-119, 2003) Incidence of asthma by school grade Follow-up from 1st grade to 6th grade 12

10 Ichikawa 8 Chiba Urban Funabashi districts Kashiwa 6 Kisarazu Ichihara Rural 4 Tateyama districts Mobara 2 Cumulative Incidence of Asthma (%) 0 1st 2nd 3rd 4th 5th 6th (Shima, et al. Arch Environ Health, 57: 529-535, 2002)

Incidence of asthma and outdoor nitrogen dioxide concentrations (1992～1994) 4.0 r 2 = 0.783 3.0 p = 0.008

2.0

1.0

Incidence of asthma (%) asthma of Incidence 0.0 0 10203040 3-yr average outdoor nitrogen dioxide (ppb) (Shima, et al. Int J Epidemiol, 29: 862-870, 2000) Associations between incidence of asthma and concentrations of NO2 and SPM 12 12 )

) 10 10

8 8

6 6

4 4 Incidence (% of asthma 2 Incidence of asthma (% 2

0 0 0 10203040 0204060 Nitrogen Dioxide (ppb) Suspended Particulate Matter (g/m3) (Shima, et al. Arch Environ Health, 57: 529-535, 2002)

Measurement of Indoor nitrogen dioxide concentrations

 The concentrations of indoor NO2 over 24 hours were measured in both the heating and non-heating periods in homes of pupils.

 The badge type passive samplers (Advantec, Tokyo, Japan) were used.

 Information on factors that could influence indoor environments was collected by questionnaire. Indoor nitrogen dioxide concentrations

(Shima, et al. Occup Environ Med, 55: 428-433, 1998)

Odds ratios (OR) for various factors on the incidence of asthma Adjusted for all variables using logistic regression model OR

Outdoor NO2 concentration, 0.01 ppm increase 2.10

Indoor NO2 concentration, 0.01 ppm increase 0.87 History of allergic diseases 7.96 Respiratory diseases before 2 yr 2.86 Breastfeeding in infancy 0.60 Parental history of allergic diseases 1.02 Maternal smoking habits 0.51 Use of unvented heaters in winter 1.26

(Shima, et al. Int J Epidemiol, 29: 862-870, 2000) Summary of epidemiologic study in Chiba, Japan

 The prevalence and incidence of asthma increased among children living near major roads relative to rural areas.

 The incidence rates of asthma were significantly increased

with increases of outdoor NO2 concentrations.  Multiple logistic regression analysis showed that 10 ppb

increase of outdoor NO2 concentrations was associated with an increased incidence of asthma (OR = 2.10).

 These findings suggest that traffic-related air pollution may be of particular importance in the development of asthma among children living near major roads with heavy traffic.

Epidemiologic study on traffic- related air pollution in Japan Background  Many epidemiologic studies have shown associations between traffic density and asthma prevalence or morbidity. However a few studies examine the relationship between asthma incidence and traffic-related exposures.  Well-designed studies are needed to assess the association between exposure to traffic-related air pollution and the onset of asthma and chronic respiratory diseases.  In view of this situation, the Japanese Ministry of the Environment has decided to launch the SORA projects (Study Of Respiratory diseases and Automobile exhaust). Study On Respiratory disease and Automobile exhaust (SORA project) “SORA” means sky in Japanese. ① Cohort study of school children（2005～） ② Nested case control study of pre-school children （2006～） ③ Survey of respiratory symptoms and pulmonary function among adults（2007～） These studies are conducted to estimate the health effects of traffic-related air pollution in adjacent to major trunk roads in Japan. ＊http://www.env.go.jp/chemi/sora/

Cohort study among schoolchildren living along trunk roads

 A school-based prospective cohort study have been conducted in the three metropolitan areas in Japan.

 In fall 2005, we enrolled 16,300 children (grades 1-3) in 57 primary schools.

 Of these schools, 49 schools are located in the districts with heavy traffic density (about 30,000-120,000 vehicles/day), and the other 8 schools are in the districts that were distant from major roads. Schema of the study districts

Study subjects（）: 1st to 3rd schoolchildren (about 16,300) Major road Study area Distant Neighboring districts districts Major roads with

School heavy traffic density (about 30,000-120,000 Exhaust vehicles/day

School School

Schedule of the study

Year 2005 2006 2007 2008 2009 Fall Fall Fall Fall Fall Questionnaire survey (grades (grades (grades (grades (grades 1-3) 2-4) 3-5) 4-6) 5-6) Fall or Blood sampling winter Mite allergen test Fall Continuous air monitoring

Indoor and outdoor four monitoring seasons

Personal exposure four monitoring* seasons *a part of subjects Data analysis will be performed before March, 2011. Schematic outline of the study

Health Effect Exposure Assessment The long-term average exposure Assessment of air pollutants (EC and NOx) is Questionnaire estimated by simulation model at the residence and the school. Blood sampling Verification Factors related to asthma Air pollution monitoring of Mite allergen test EC and NOx Questionnaire Measurements of personal exposure to NOx

Evaluation of the association between exposure to traffic- related air pollutants and the onset of asthma among children

Provisional results of continuous air monitoring

 The concentrations of PM2.5, black carbon (BC), and NOx have been continuously measured at 4 sites (0m, 20m, 50m, 100m) near each of 10 major roads and 7 sites distant from major roads.

BC concentrations in March, 2006 NOx concentrations in March, 2006 6 0.12 5 0.10 ) 3 4 0.08 g/m 3 μ ppm)

（ 0.06 （ 2 BC 0.04 NOx 1 0.02 0 0.00 0ｍ 20ｍ 50ｍ 100ｍ distant place 0ｍ 20ｍ 50ｍ 100ｍ distant place Distance from the roadside Distance from the roadside Conclusions

 Various efforts during the past several decades have improved industrial air pollution.  The problems of traffic-related air pollution have been rising in response to the increase of automobiles.  Some studies suggest the health effects of traffic- related air pollution. However, the relationship between the incidence of asthma and traffic-related exposures should be further evaluated.  Further studies are also needed to clarify the health effects of fine particles in relation to automobile traffic.

谢谢！

Thank you very much for your attention.

(Outlook from Mt. Rokko, Hyogo)