Levels of mercury in Moroccan breast milk and the affecting factors: CONTAMILK study

This study aims to evaluate the level of mercury in the breast milk of Moroccan mothers and its association with several maternal parameters and habits, and to estimate the daily intake of the newborns. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the concentrations of mercury in 70 colostrum samples. Indeed, a structured questionnaire was administrated during milk collection to report data concerning the maternal socioeconomic and anthropometric parameters, as well as dietary habits and smoking habits in the family, etc. The median of mercury in breast milk was 3,56 μg/L (range 1.64-124 μg/L) and exceeded normal levels of 1.7 μg/l, suggested by the World health organization in 99% of milk samples. Significant associations were found between mercury levels and the occurrence of previous miscarriages, anemia before pregnancy and vitamin & mineral supplementation during pregnancy, as well the frequency of consumption of cereals and the use of lipstick. The estimated daily intake was higher than the tolerable daily intake of the World health organization and the European food safety authority in 30% of newborns. These results need to be confirmed by multicenter studies to investigate the levels of mercury in the breast milk of the Moroccan population.

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 μg/L (range 1.38-515,39 μg/L) and in 79 % of samples, levels were higher than the normal range reported by the World Health Organization (WHO) in BM (2-5 μg/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 μg/kg/day) for 39 babies and 6 babies according to the WHO (3.6 μg/kg/day).

Cadmium Contamination in Breast Milk of Moroccan Lactating Women and the Associated Factors: CONTAMILK Study

The objectives of this study were to assess levels of contamination of breast milk (BM) by cadmium (Cd) among lactating mothers from Rabat, Morocco, and to investigate its association with several maternal habits, parameters, and factors. In addition, to estimate the daily intake of the newborns. Cd concentrations were measured by inductively coupled plasma-mass spectrometry (ICP-MS) in 70 human milk samples collected between the 2nd and 5th day postpartum. Accuracy of the analysis was checked by various methods including the use of reference material. A structured questionnaire was filled during the collection of milk reporting data concerning anthropometric, sociodemographic parameters, dietary and cosmetic habits, etc. The median (range) of Cd in human milk was 0.49 μg/L (range 0.013-95.19 μg/L) respectively. In 21 (30%) of 70 samples, Cd levels were higher than the normal reported by the World Health Organization (WHO) in BM (< 1 μg/L). Indeed, several factors affect significantly Cd levels in BM of the mothers such as low maternal education level, preterm delivery, cesarean delivery, and area of residence. Also, the frequency of consumption of milk and dairy products as well dried fruits and wheat bread and the frequency of use of cosmetic powders. However, the daily intake of cadmium by the newborns was lower than tolerable daily intake of the WHO for 97% of them. Our results revealed low cadmium concentrations in human milk samples from Moroccan lactating mothers living in Rabat, also the association of some factors with the levels of contamination found in this population.