It is well known that water colours and poster colours are made of inorganic pigments that then contain metals such as Cr, Pb, Fe, Co, Cd, Hg etc.. Recently, promoting the culture of sentiments, children practice painting with their fingers using water colours and poster colours, that is called the finger-painting. It is possible that inorganic metals contained in water colours and poster colours are potentially hazardous to children who practice painting in a private school. Each of four colours of red, blue, yellow and green of water colours and poster colours was analyzed for Cr, Pb, Fe, Co, Cd and Hg. And urinary Pb and Cd were determined on twenty five children, ages 4 to 11 of a private school of the painting and five control children ages 3 to 11. The following results were obtained.
1) On the whole, water colours and poster colours contained a large quantity of Fe and Pb next to Fe. Especially yellow-2 of water colours contained a large quantity of Pb and showed 1, 012.5μg/g. The dissolved lead was found in water colours that were in lead tubes.
2) The average of urinary Pb of tested children was 6.07±6.67μg/l(n=15), and that of control children 2.20±2.59μg/l(n=5). There were not significant difference at levels of 5% between the mean of subjects and that of the control.
3) The average of urinary Cd of subjects was 0.68±0.94μg/l(n=25), and that of the control 0±0μg/l(n=5). There were not significant difference at levels of 5% between the mean of subjects and that of the control.
4) The coefficient of correlation between experimental length in years and urinary Pb was 0.98, its regression line being yPb=3.18x+2.17(±2.92) as yPb for urinary Pb and x for experimental length in years.
5) The coefficient of correlation between experimental length in years and urinary Cd showed 0.91, its regression line being yCd=0.23x+0.11(±0.25) as yCd for urinary Cd and x for experimental length in years.
6) The coefficient of correlation between ages and urinary Pb was 0.10, and that between ages and urinary Cd was 0.72. Urinary Cd was apt to increase in proportion to ages.
