Lead concentrations in breast milk of Moroccan nursing mothers and associated factors of exposure: CONTAMILK STUDY

The aim of CONTAMILK study was to estimate levels of contamination of breast milk (BM) of Moroccan nursing mothers by some xenobiotics including, lead (Pb), to identify associated factors of exposure and to determine the daily intake of newborns. Lead concentrations were determined in 70 samples of colostrum by ICPMS and a structured questionnaire was filled during milk collection to report participants' data. The median lead concentration was 908 mu g/L (range 1.38-515,39 mu g/L) and in 79 % of samples, levels were higher than the normal range reported by the World Health Organization (WHO) in BM (2-5 mu g/L). Indeed, preterm delivery, frequency of use of cosmetic powders and lipsticks were significantly associated with the level of lead in BM. The estimated daily intake was greater than the tolerable daily intake (TDI) of the European food safety authority (0.5 mu g/kg/ day) for 39 babies and 6 babies according to the WHO (3.6 mu g/kg/day).

Automated summary

The CONTAMILK study aimed to estimate contamination levels of breast milk in Moroccan nursing mothers by lead and other xenobiotics, identify associated factors, and determine newborns' daily intake. Lead concentrations in colostrum samples were found to be higher than the normal range, with factors such as preterm delivery and cosmetic usage significantly influencing the levels. Some babies had daily intake levels exceeding the tolerable daily intake set by European food safety authority and WHO.