ABSTRACT
Following birth, the fetal stage develops into the neonate or infant stage. Exposure to drugs and environmental agents can be either direct through inhalation, ingestion, etc. or indirectly via the mother’s milk. The importance and necessity of breast milk in the developing neonate have been clearly shown (Kacew, 1994; Berlin and Kacew, 1997). Box 10.1 lists some of the disease conditions where the frequency of occurrences of these disorders was clearly diminished in breast-fed infants. Breast-feeding has distinct advantages nutritionally, immunologically, and psychologically, and despite the presence of environmental toxins, should be encouraged. At present, it should be stressed that human milk remains the best nutrient source for the healthy term infant (Redel and Shulman, 1994). This is clearly evident from the emphasis both professionals and laypersons place on the promotion of breast-feeding. The incidence of breast-feeding in North America has varied over the years from 25% (1970) to 56% (1981), and some studies show that about 54% of women discharged from hospital to home are breast-feeding (Berlin, 1989; Lawrence, 1989; Buttar, 1994). The resurgence in the number of women breast-feeding will increase even further as the educational awareness of benefi ts of lactation is promoted amongst men of expectant mothers. Wilson et al. (1986) estimated that a fi gure of 70% of breast-feeding mothers in the United States was equivalent to approximately 2.5 million women. Even at 50%, in 1994, there were 4 million new mothers in the United States, so more than 2 million infants went home receiving breast milk. A health goal established by a workshop sponsored by Human Health Services was that, by the year 2000, 75% of newborns would be breast-fed and 50% would still be breast-fed by six months of age. Meta-analyses of long-term effects of breast-feeding also demonstrated that the prevalence of overweight/obesity/type-2 diabetes is lower in breast-fed subjects (Horta et al., 2007). In addition, women who had breastfed for a lifetime total of at least two years are associated with a 23% lower risk of coronary heart disease than those who had never breastfed (Stuebe et al., 2009). However, the breast-feeding mother is subjected to exposure from environmental contaminants
(e.g., heavy metals, xenoestrogens, pesticides, and solvents), and these pollutants may be present in human milk (Massart et al., 2005). In the majority of cases, it is still more benefi cial to breast-feed despite the presence of such contaminants. Recently, the use of plastic baby bottles containing a chemical, bisphenol A (BPA), was linked to the development of abnormal endocrine functions in animals. Although excessive concentrations of BPA produced these changes in non-human organisms, regulatory agencies in some countries banned the use of this chemical in baby bottles. In the case of breast feeding there was no exposure of lactating infants to BPA again pointing out an advantage for breast versus bottle feeding.
