title: Age dependence of metals in hair in a selected U.S. population.
abstract: Concentrations of 28 metals were determined in hair samples from 199 children (age less than or equal to 12 years) and 322 adults (age 13-73) years. Levels of calcium, barium, magnesium zinc, and strontium all show a similar age-dependent increase up to about 12-14 years; levels of aluminum show a decrease with age. Relationships of elemental concentrations with age were examined by using correlation, linear regression, t tests, and discriminant analysis. Statistically significant differences in mean concentration values between children and adults were shown for these metals. Discriminant analysis gave about 95% accuracy in classifying a test data set into the categories of children and adults. A hypothesis suggested by the data is that there is an age-dependent excretion in hair of alkali metals during skeletal growth and development. The observed decrease in aluminum is largely unexplained at this time.
authors.affiliation: Division of Environmental Health Laboratory Sciences, Centers for Disease Control, Atlanta, Georgia 30333.
authors.forename: D C
authors.initials: DC
authors.lastname: Paschal
authors.forename: E S
authors.initials: ES
authors.lastname: DiPietro
authors.forename: D L
authors.initials: DL
authors.lastname: Phillips
authors.forename: E W
authors.initials: EW
authors.lastname: Gunter
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006197:Hair / Q000032:analysis*; D006801:Humans; D007223:Infant; D008297:Male; D008670:Metals / Q000032:analysis*; D008875:Middle Aged
chemical_list: D008670:Metals