Statistical investigations into the measured DALA--discharge in the urine of infants

Using a sample of the size 353 on day-nursery children, the authors show that the DALA-U increase, which is due to the absorption of lead and other substances, does not display any age or sex dependence. A dependence upon the day nursery's location is assumed. The authors elaborate on the statistical problems (normal distribution) and the boundary value problems associated with the various DALA-U values measured. Large sample sizes are required to find a final clarification of the relationships.