Personal carbon monoxide exposures of preschool children in Helsinki, Finland: levels and determinants

Personal CO exposures of 194 preschool children were measured with personal exposure monitors during a 24 week sampling period from fall 1990 to spring 1991 in Helsinki, Finland. Arithmetic mean of the maximum 1 and 8 h exposure levels were 6.0 and 3.3 mg m−3. The then Finnish ambient air quality guideline values for 1/8 h maximum CO level (30/10 mg m−3) were exceeded in 2/4% of the childrenʹs daily maximum 1/8 h exposure levels. Gas stove at home, parents, especially mother, smoking in the home, and living in high rise buildings — reflecting higher local population and traffic density — increased the childrenʹs CO exposures. The presence of a fireplace in the home was associated with decreased CO exposures. Fatherʹs high education reduced the childrenʹs CO exposure while motherʹs education level had no significant effect. The peak (15 min) exposure levels of the children commuting to day care center by car or bus were higher than those of the children who walked or came by bike.