Intra- and Inter-Day Element Variability in Human Breast Milk: Pilot Study.

Kenta Iwai,Shoji F Nakayama,Miyuki Iwai-Shimada,Yayoi Kobayashi,Nozomi Tatsuta,Kunihiko Nakai,Kaname Asato

doi:10.3390/toxics10030109

Kenta Iwai, Shoji F Nakayama + Show 5 more

Open Access

https://doi.org/10.3390/toxics10030109

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Abstract

For infants in the first months of life, breast milk is a complete source of nutrition; however, it can also contain elements that are harmful to the infant. It is therefore critical for infant health to characterize breast milk. The aim of this study was to determine the intra- and inter-day variation of elements in breast milk, for which there is currently limited information, as a pilot study for a larger study. Firstly, we developed a simple and robust analytical method for the determination of multiple elements in breast milk. It was accurate (accuracy ranged from 98% to 107%) for measurement of 26 elements in breast milk by quadrupole inductively coupled plasma-mass spectrometry. Intra- and inter-day variation of elements, protein, and fat in breast milk was determined by analyzing breast milk collected from 11 women at 12 sampling points over three days and calculating intraclass correlation coefficients. Intraclass correlation coefficients showed that while some elements were consistent across time points (e.g., Sr, Ca, and Cu), others showed very high variability (e.g., As, Cd, and Ni). Correlation analyses between elements in breast milk showed strong relationships between those including Fe and Mo, Ca and Sr, and Cd and Fe.

Highlights

IntroductionBreast milk is a complete source of infant nutrition in the first few months of life
Breast milk is a complete source of infant nutrition in the first few months of life.It is a complex biological matrix consisting of nutrients [1], and other important components, including antibodies, enzymes, growth factors, hormones, cytokines, exosomes, and stem cells [2,3]
Persistent organic pollutants, polychlorinated biphenyls and poly- and perfluoroalkyl substances [4,5], pharmaceuticals [6], [7], and toxic elements [8,9] have been detected in breast milk

Summary

Introduction

Breast milk is a complete source of infant nutrition in the first few months of life. It is a complex biological matrix consisting of nutrients (proteins, fats, carbohydrates, minerals, and vitamins) [1], and other important components, including antibodies, enzymes, growth factors, hormones, cytokines, exosomes, and stem cells [2,3]. Breast milk may contain potentially harmful components, since some chemicals taken in by the mother (ingested, inhaled, transdermal, and injected) pass into breast milk. Persistent organic pollutants, polychlorinated biphenyls and poly- and perfluoroalkyl substances [4,5], pharmaceuticals [6], [7], and toxic elements [8,9] have been detected in breast milk. There are concerns about the potential impact of these chemicals and toxic elements on infants, these effects have not been fully elucidated. Since infancy is a period of rapid development and growth, and infants have an immature digestive system and blood-brain barrier, they are as susceptible to adverse toxin responses as fetuses

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