Elementos inorgánicos y compuestos perfluorados en leche materna de mujeres residentes en zona industrial/minera y en zona agrícola de la región de murcia

Abstract

ABSTRACT Introduction Breast milk is the ideal food for infants, who should be exclusively breastfed for the first six months of life. After that, they should start receiving other foods in addition to breast milk. There are countless benefits for the infants as well as for both the mothers and the environment. However, breast milk may also pass on toxic chemicals to the infants. The characteristics and history of the mining and industrial area of Cartagena and its environs evidence high contamination levels, with figures exceeding those allowed by the WHO, with increased morbidity and mortality based on different studies. The general purpose of this paper is to assess the different inorganic constituents and perfluorinated compounds in the breast milk of women who live in an industrial/mining area and in an agricultural area in the Murcia region. Material and methods Prospective double-blind cross-sectional study. We took 77 samples of breast milk from mothers living in the two areas: mining/industrial and agricultural. We surveyed all the participants, asking them about the characteristics of the child and mother, their food and their maternal habits. The samples of the inorganic constituents were analysed after being cooled using inductively coupled plasma mass spectrometry (ICP-MS) and the perfluorinated compounds using high-performance liquid chromatography coupled with electrospray ionisation tandem mass spectrometry (HPLC-MS). The toxic inorganic constituents chosen were lead, cadmium, mercury, arsenic, zinc, copper, aluminium, chrome, nickel, manganese, iron and selenium, while the perfluorinated compounds were PFOA, PFNA, PFDA, PFDoDA and PFUnDA. Results In all the cases and in variable proportions depending on the compound, the levels obtained were higher than those recommended by the international agencies such as the WHO (World Health Organization), except for the perfluorinated compounds (PFCs). Several correlations stood out: the maternal age had a positive correlation with the aluminium levels in milk; the years spent living in an industrial/mining area had a positive correlation with the nickel levels but a negative one with the zinc levels. The infant's age had a negative correlation with the zinc and cadmium levels in breast milk; the newborn's weight had a negative correlation with the arsenic levels; and the infant's current weight had a negative correlation with the cadmium and copper levels in breast milk. Vegetarian mothers had higher levels of lead, arsenic, cadmium and manganese in breast milk.. Smoking was associated with higher cadmium levels in breast milk. In other correlations, the number of months that the mother breastfed, including the months breastfeeding other previous children, had a negative correlation with the PFOA levels and the PFUnDA levels were significantly higher among vegetarians than among non-vegetarians. The consumption of white fish by mothers had a positive correlation with the PFOA levels in breast milk. Conclusions The medium and/or maximum levels of the various inorganic constituents analysed in the breast milk addressed by this paper exceeded, in all cases, the concentrations recommended by the World Health Organization and other international agencies, and may constitute a high risk for the population, especially expectant mothers and their children. We detected levels of the various perfluorinated compounds (PFCs) in the milk of the mothers addressed by the paper, where the perfluorooctanoic acid (PFOA) level was lower than the maximum tolerable concentrations issued by the European Food Safety Authority (EFSA).