Interrelationships between the concentration of magnesium, calcium, and strontium in the hair of Japanese school children.

Inductively coupled atomic emission spectrometry was used for the determination of magnesium, calcium and strontium in the hair of Japanese school children (7-15 years of age, 158 males and 184 females). Sex-related differences in the levels of the three alkaline earth metals were observed (T-test, p less than 0.001). Geometric means (SD) of the concentrations of magnesium, calcium and strontium were 30.40 (1.42), 326.3 (1.62) and 0.509 (2.04) micrograms g-1 for males and 61.21 (1.73), 643.4 (1.57) and 2.749 (2.14) micrograms g-1 for females. For both sexes, significant positive correlations were observed between all concentration pairs of the three elements. The concentration ratios between any two of the three elements were also determined. The geometric mean of the concentration ratio of calcium to magnesium for males [10.73 (1.54)] is not significantly different from that for females [10.51 (1.40)] (T-test, p greater than 0.05). On the other hand, concentration ratios of magnesium to strontium [59.71 (1.99)] and calcium to strontium [640.9 (1.74)] for males are significantly higher (T-test, p less than 0.01) than those for females [22.27 (1.60) and 235.9 (1.65)]. The logarithmic-transformed ratio of magnesium to strontium has a strong positive correlation with the transformed ratio of calcium to strontium [r = 0.9529 (p less than 0.001) for males and r = 0.7284 (p less than 0.001) for females].