POTENTIAL ALUMINUM TOXICITY IN INFANTS FED SPECIAL INFANT FORMULA

Aluminium was measured in samples of plasma and samples of feed obtain ed from 74 infants with normal renal function established on various f eeds (breast, whey-based, fortified whey-based, preterm, soy, and case in hydrolysate). All infants were bolus fed, and blood samples were co llected midway between feeds. Aluminium was measured using electrother mal atomization and atomic absorption spectrometry. Mean aluminium con centrations in milks were as follows: breast, 9.2 mu g/L [95% confiden ce interval (CI), 5.6-12.7]; whey-based, 165 mu g/L (95% CI, 151-180); fortified, 161 mu g/L (95% CI, 143-180); preterm, 300 mu g/L (95% CI, 272-328); soy, 534 mu g/L (95% CI, 470-598); casein hydrolysate, 773 mu g/L (95% CI, 632-914). Mean plasma aluminium concentrations in infa nts receiving different milks were as follows: breast, 8.6 mu g/L (95% CI, 5.6-10.6); whey-based, 9.2 mu g/L (95% CI, 7.4-11.0); fortified, 10.3 mu g/L (95% CI, 8.3-12.3); preterm, 9.7 mu g/L (95% CI, 5.3-17.1) ; soy, 12.5 mu g/L (95% CI, 5.0-20.0); casein hydrolysate, 15.2 mu g/L (95% CI, 10.7-19.8). Mean plasma aluminium concentration was signific antly different in infants fed casein hydrolysate formulae than in tho se fed breast milk (difference, 6.7 mu g/L; 95% CI, 2.8-10.5; p = 0.02 8). We conclude that infants may be at risk from aluminium toxicity wh en consuming formula containing >300 mu g/L-in particular, casein hydr olysate formulae. We speculate that the aluminium compounds found in b reast milk are more bioavailable than those found in other milks and t hat some constituents of infant formula affect aluminium absorption fr om the gut lumen.