Breast Milk and Hair Testing to Detect Illegal Drugs, Nicotine, and Caffeine in Donors to a Human Milk Bank

Abstract

Background: The use of illegal drugs and tobacco is an exclusion criteria for accepting a nursing mother as a milk donor. The detection window for human milk testing is typically a few hours. Hair testing has been considered the gold standard to assess chronic exposure to these toxic substances. Objective: The aim of this study was to determine the levels of illegal drugs, nicotine, and caffeine in breast milk and hair samples from donors to assess whether these substances were being used during the donation period and the months leading up to it. Methods: Thirty-six samples of hair and breast milk were obtained from 36 donors. The tests performed identified nicotine, caffeine, morphine, cocaine, cannabis, amphetamines, codeine, methadone, and other substances derived therefrom. Results: No illegal drugs were found in any of the samples analyzed. Nicotine and cotinine were found in 33.3% (12/36) of all hair samples. Among these 12 samples, 10 had cotinine concentrations consistent with cutoff values for unexposed nonsmokers, 1 had concentrations consistent with cutoff values for passive smokers, and 1 had concentrations consistent with cutoff values for active smokers. Caffeine was found in 77.7% of the hair samples and in 50% of the donor milk samples. The correlation for caffeine between donor milk and hair samples was r = 0.288, P = .0881. Conclusion: Donors do not use illegal drugs during either the donation period or the months leading up to it. They are occasionally exposed to tobacco smoke and almost all of them consume caffeine.