Abstract
(1) Inorganic sulphate content of human milk is subject to a very great fluctuation though the sulphate content will not show a very wide difference of figures in one and the same individual.
(2) The Arakawa-positive milk shows an average of 6.2mgrms. % and the Arakawa-negative an average 9.3mgrms. %, while all the cases show an average of 8.7mgrms. %. The average of the figures of Arakawa-negative milk is about one and half times as large as that of Arakawa-positive milk. The more remarkable the degree of negativity, the larger is the sulphate content.
(3) There is no difference of sulphate content of human milk on different sides of the breast, provided the comparison is made between samples of the same kind with respect to Arakawa's reaction. (4) Both Arakawa-positive and -negative milks show larger figures of sulphate, as the age of the mother becomes increased.
(5) Colostrum milk is particularly rich in sulphate. There is no marked difference of sulphate content between the early mature and the middle mature periods, but the sulphate seems to grow rather rapidly larger after one year.
(6) In winter the sulphate seems to be of the smallest value.
(7) Though there may be a difference of inorganic sulphate content of human milk according to ages of lactating mothers, to periods of lactation and to different seasons, such a difference will be markedly smaller as compared with that according to the different intensity of Arakawa's reaction.
