Ryoji Sakai
University of Tokyo
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Social Science & Medicine | 2004
Akiko Otsu; Shunichi Araki; Ryoji Sakai; Kazuhito Yokoyama; A.Scott Voorhees
The relationships between male or female age-adjusted suicide mortality and social life factors for all 47 Japanese prefectures in 1980, 1985 and 1990 were investigated by stepwise multiple regression analysis after classification of 20 social life indicators by factor analysis. During this period, Japan experienced the second economic crisis (the so-called secondary oil crisis) in 1980-1983 and economic prosperity (bubble economy) in 1986-1990. In all the three years, male suicide mortality was significantly related inversely to the urbanization and economic development factor, the result of which was consistent with the data in our previous study for the years 1970 and 1975. Similarly, the male mortality was positively related to the factor of migration of workers in the three years. No factor significantly related to female mortality for all the three years was found. It is suggested that (1) urbanization was a major determinant which prevented male suicide mortality during the past 20 years (1970-1990) in Japan; (2) migration of workers became an important factor for male suicide mortality during these 10 years; and (3) female suicide mortality was less vulnerable to social life factors for these 20 years than the male mortality.
Archives of Environmental Health | 1983
Shunichi Araki; Katsuyuki Murata; Koichi Ushio; Ryoji Sakai
The dose response relationship between tobacco consumption and melanin pigmentation in the attached gingiva was examined on two occasions 4 years apart in a group of Japanese lead workers with blood lead concentrations below 2.0 mu mol/kg (40 micrograms/100 g). In the two examinations, 12% and 18% of the total group of workers and 17% and 24% of the smokers had melanin pigmentation. The prevalence of pigmentation was significantly higher in smokers who inhaled more than 10 cigarettes per day (17% and 25%) than in nonsmokers (0% and 2%), and tended to increase significantly with tobacco consumption. Lead absorption was not associated with melanin pigmentation.
Industrial Health | 2008
Shunichi Araki; Ryoji Sakai; Kazuhito Yokoyama; A. Scott Voorhees
Effects of nine social life indicators on age-adjusted and age-specific annual suicide mortality of male and female Japanese population in the years 1953-96 were investigated by multiple regression analysis on time series data. Unemployment rate was significantly related to the age-adjusted mortality in both males and females. Also, female labour force participation was positively related to the male mortality; persons and 65 and above was inversely related to the male mortality. Results on the age-specific mortality indicated that: during the 44 yr, (1) unemployment significantly related with the mortality of young, middle-aged and elderly males and young females; (2) female labour force participation significantly related with the mortality of young and elderly males and young females; aged population significantly related with the mortality of middle-aged and elderly males; (4) young population significantly related with the mortality of young and middle-aged males and females; (5) divorce significantly related with the mortality of middle-aged and elderly males and young males and females; (6) persons employed in primary industries significantly related with the mortality in middle-aged males and young males and females; and (7) population density significantly related with the mortality of middle-aged males and young females.
Journal of The Air & Waste Management Association | 2000
Voorhees As; Shunichi Araki; Ryoji Sakai; Hajime Sato
ABSTRACT The benefits and costs of past nitrogen dioxide (NO2) control policies were calculated for Tokyo, Japan, using environmental, economic, political, demographic, and medical data from 1973 to 1994. The benefits of NO2 control were estimated as medical expenses and lost work time due to hypothetical no-control air concentrations of NO2. Direct costs were calculated as annualized capital expenditures and 1 years operating costs for regulated industries plus governmental agency expenses. The major findings were as follows: (1) Using Tokyos average medical cost of pollution-related illness, the best net estimate of the avoided medical costs due to incidence of phlegm and sputum in adults was 730 billion yen (
Environmental Health and Preventive Medicine | 2001
S. Scott Voorhees; Ryoji Sakai; Shunichi Araki; Hajime Sato; Akiko Otsu
6.08 billion; 1 U.S. dollar = 120 yen). (2) The best net estimate of the avoided medical costs due to incidence of lower respiratory illness in children was 93 billion yen (
Cancer | 1984
Wataru Mori; Ryoji Sakai
775 million). (3) Using Tokyos average duration of pollution-related illness and average wages, the best net estimate of the avoided costs of lost wages in workers was 760 billion yen (
Journal of Environmental Planning and Management | 2001
A.Scott Voorhees; Ryoji Sakai; Shunichi Araki; Hajime Sato; Akiko Otsu
6.33 billion). (4) The best net estimate of the avoided costs of lost wages in mothers caring for their sick children was 100 billion yen (
Environmental Research | 2002
Ryoji Sakai; H. C. Siegmann; Hajime Sato; A.Scott Voorhees
833 million). (5) Using Tokyo-specific data, the best net costs were estimated as 280 billion yen (
Japanese journal of public health | 1999
Shunichi Araki; Tadashi Sakai; Hajime Sato; Tetsuya Kaneko; Ryoji Sakai; Kazuhito Yokoyama
2.33 billion). (6) Using human health and productivity benefits, and annualized capital cost and operating cost estimates, the best net benefits-to-costs ratio was 6:1 (upper limit 44:1; lower limit 0.3:1). Benefit calculations were sensitive to assumptions of mobile source emissions and certain health impacts that were not included. Cost calculations were highly dependent on assumptions of flue gas volume and fuel use. For comparative purposes, we identified other studies for air pollution-related illness. Assumptions that formed the basis for most of the inputs in the present study, such as duration of illness, medical treatment costs, per person illness in children, and lost wages for working mothers, were similar to those recommended in the literature. Lost wages in sick workers and per capita illness incidence in adults were higher than numbers reported elsewhere. Further advances in cost-benefit analysis (CBA) procedures to evaluate the economic effectiveness of NO2 controls in Tokyo are recommended to estimate impacts and values for additional human health benefits, ecosystem health and productivity effects, and nonliving system effects, as well as benefits of ancillary reductions in other pollutants. The present study suggests that Tokyos past NO2 control policies in total were economically quite effective.
Industrial Health | 1991
Hui-Qing Jin; Shunichi Araki; Xi-ke Wu; Y. W. Zhang; Lu-Ling Duan; Ryoji Sakai
The most common method of evaluating beneficial impacts of environmental policies is cost-benefit analysis (CBA). In the present review, CBA methods for air pollution impacts are reviewed. Three types of air pollution effects are identified, including health, productivity, and amenity. Market valuation, stated preference methods, and revealed preference methods are identified for valuing benefits. Three types of costs are deseribed, including private sector costs, societal costs, and governmental regulatory costs. A benefits valuation approach based on Freemans principals is described. A costs valuation approach based on U.S. Environmental Protection Agency and Dixon et al. principals is deseribed. Limitations associated with estimates of benefits and costs are summarized. Input assumptions and results are compared for several existing air pollution control analyses. The importance of CBA in environmental policy studies is discussed. Our conceptual approaches should be useful in analyses of urban air pollution impacts and air pollution prevention policies.