Tests for the adulteration of human milk.

The necessity for testing human milk destined for milk banks in order to eliminate specimens which have been adulterated with water or cow's milk has been widely recognized since the introduction of such banks in 1910 (Mackintosh, 1947). In some centres, however, no tests for adulteration seem to be used, in spite of the fact that the mothers providing milk for these banks are not supervised between the time they express the milk and deliver it to the milk bank or milk bank official. Various tests have been used to detect adulteration, and there is to this day no agreement on which are most reliable. The selection of tests in the past has depended partly on the efficiency of a test but also on other factors such as the speed and ease with which a test can be performed, the simplicity of the apparatus, the ease with whih reagents and sera can be obtained, and financial considerations. It would appear therefore that the ideal test or combination of tests used in the detection of adulteration of human milk with water or cow's milk should be quick and easy to perform and preferably should not involve compliated or expensive apparatus. The test must be reliable and able to detect minor degrees of adulteration. With these criteria in mind the many tests recommended for the detection of adulteration have been reviewed and those which best fulfil the conditions selected for discussion. In addition an investigation has been made into the freezing point of women's milk; the value of assessing the freezing point or the elctrical conductivity of women's milk for the detection of adulteration of the milk has been explored.