Marilou M. Saong, ChE, MSMath, PhD Irene B. Rodriguez,BSChem, MSChem, PhD Riza A. Magbitang, BSChem
Breast milk is the primary source of nutrition for infants and the practice of breastfeeding is highly promoted all over the world. But this important source of nutrients may also be the pathway of exposure for infants to unwanted contaminants like arsenic (As), cadmium (Cd) and lead (Pb) due to maternal excretion. Analyses of the trace contaminants in the breast milk samples from volunteer mothers in Baguio City, Philippines was done using an optimized method based on microwave digestion as the mineralization step prior to metal-selective detection by inductively coupled plasma mass spectrometry (ICPMS). The method was validated against a certified reference material (spiked skim milk powder) and by standard addition. The breast milk samples analyzed showed a range of concentration for As: from below method detection limit (MDL) to 12.02 µg L-1 (mean value of 3.04 µg L-1); for Cd: from below MDL to 0.70 µg L-1 (mean value of 0.11 µg L-1); and for Pb: from below MDL to 20.04 µg L-1 (mean value of 1.93 µg L-1). These concentrations, except the determined As values, were below the reported values in other countries and the reported values by the World Health Organization. Correlation analysis showed that there was a moderate but significant correlation between levels of Cd and Pb indicating that lactating mothers with high levels of Cd also had high levels of Pb. Although the levels of As, Cd and Pb in breast milk samples from volunteer mothers are low compared to reported levels from other parts of the world, the presence of these elements in the samples indicates that there is a need for a wider study to ascertain which may be possible sources for these contaminants, especially in lactating women.
Key words: Breast milk, metal contamination, arsenic, cadmium, lead, ICPMS
June 17, 2014
UB RJ Vol. XXXVII, No. 1 2013