Summary of statistics of population, number of deaths, hourly mean concentration of air pollutants, and hourly mean temperature and relative humidity in the 13 major urban areas studied
| Population in 1990 (in thousands) | Number of deaths, 1990–94 (65 years or older) | Mean concentration of air pollutants, temperature, and relative humidity in warmer months (April to September), 1990–94 | Mean concentration of air pollutants, temperature, and relative humidity in colder months (October to March), 1990–94 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All age | 65 years or older | ICH | IS | Temp | RH | PM7* | NO2 | Ox | Temp | RH | PM7* | NO2 | Ox | |
| ICD-9: 431 | ICD-9: 434 | °C | % | μg/m3 | ppb | ppb | °C | % | μg/m3 | ppb | ppb | |||
| *Defined under the Japanese Air Quality Standard as any particles collected with an upper 100% cut-off point of 10 μm aerodynamic diameter. The 50% cut-off diameter for the particles is assumed to be approximately 7 μm (PM7). | ||||||||||||||
| ICH, intracerebral haemorrhage; IS, ischaemic stroke; Temp, temperature; RH, relative humidity; Ox, photochemical oxidants. | ||||||||||||||
| Sapporo | 1672 | 152 | 595 | 2140 | 16.4 | 70.2 | 20.6 | 27.0 | 15.8 | 2.4 | 68.6 | 21.0 | 33.7 | – |
| Sendai | 918 | 80 | 421 | 1486 | 18.5 | 75.1 | 33.1 | 14.8 | 25.5 | 6.9 | 66.5 | 24.2 | 17.9 | 23.8 |
| Chiba | 829 | 61 | 384 | 983 | 21.5 | 74.3 | 41.9 | 16.9 | 22.3 | 10.4 | 63.1 | 54.5 | 27.4 | 14.4 |
| Tokyo | 8164 | 911 | 6337 | 16786 | 22.1 | 67.8 | 43.0 | 31.4 | 19.8 | 10.7 | 57.5 | 55.8 | 38.4 | 14.1 |
| Yokohama | 3220 | 278 | 1458 | 3856 | 21.5 | 74.4 | 44.1 | 36.9 | 13.3 | 10.4 | 62.5 | 51.5 | 44.6 | 10.7 |
| Kawasaki | 1174 | 94 | 1252 | 2854 | 21.5 | 74.4 | 57.4 | 31.9 | 18.3 | 10.4 | 62.5 | 62.2 | 40.5 | 12.3 |
| Nagoya | 2155 | 222 | 1600 | 4276 | 22.3 | 68.3 | 45.2 | 19.3 | 24.4 | 9.8 | 64.7 | 44.0 | 30.2 | 14.9 |
| Kyoto | 1461 | 185 | 965 | 2440 | 22.5 | 66.2 | 33.3 | 22.7 | 27.3 | 9.7 | 67.7 | 28.4 | 26.5 | 18.4 |
| Osaka | 2624 | 306 | 625 | 1686 | 23.3 | 65.1 | 46.4 | 30.5 | 21.4 | 11.0 | 62.2 | 41.9 | 35.9 | 13.9 |
| Kobe | 1477 | 169 | 1675 | 4494 | 22.3 | 70.6 | 38.3 | 20.1 | 29.5 | 10.3 | 65.1 | 29.8 | 20.3 | 24.7 |
| Hiroshima | 1086 | 107 | 648 | 1563 | 22.8 | 69.3 | 44.4 | 19.9 | 25.9 | 10.3 | 67.5 | 36.2 | 24.1 | 17.0 |
| Kitakyushu | 1026 | 130 | 753 | 2351 | 22.7 | 72.9 | 39.3 | 20.7 | 21.6 | 11.3 | 66.6 | 28.2 | 24.3 | 20.7 |
| Fukuoka | 1237 | 113 | 641 | 1455 | 22.7 | 72.9 | 37.5 | 25.6 | 19.8 | 11.3 | 66.6 | 33.9 | 30.4 | 19.3 |
| Total | 27043 | 2,808 | 17354 | 46370 | 21.5 | 70.4 | 40.3 | 24.4 | 21.9 | 9.4 | 64.7 | 39.4 | 30.3 | 17 |