pollution in the United States, have suggested an association with neonatal mortality.
A number of large-scale British studies have evaluated the effects of air pollution on the health of children. Colley and Reid (1970) surveyed respiratory disease prevalence in 1966 in over 10,000 children 6–10 years old in England and Wales with a questionnaire and measured peak expiratory flow rates. A social-class gradient was observed for chest disease, but a pronounced increase in prevalence was observed in each social class in association with greater pollution. This was particularly true in the children of unskilled and semiskilled workers. An unexplained excess in prevalence in Wales may represent an ethnic difference. Small differences in peak expiratory flow rate were found when the results were calculated independently for those with and without a history of respiratory disease or symptoms. The authors point out that differences may have been obscured by difficulties in standardizing the observers and the 70 peak flow meters used in the study.
Another British study of over 10,000 children was performed at about the same time by Holland et al. (1969) in different areas of Kent. They observed independent and additive effects of social class, family size, history of significant respiratory disease, and area of residence on pulmonary function, as measured by peak expiratory flow rate. Residential area appeared to have the greatest influence on pulmonary function; this suggested an effect of air pollution. However, the authors note that all four factors together accounted for only about 10–15 percent of the total variation; other determinants, possibly including host factors, are probably also important. Only minimal pollutant monitoring data are presented that describe the monthly average smoke concentrations in three of the four areas studied for November 1966 to March 1967. In the most polluted area, which had the lowest peak expiratory flow rates, the highest recorded monthly average smoke shade was 96 ug/m3.
A study by Douglas and Waller (1966) evaluated over 3,000 children 15 years old who