Concentrations of lead in maternal blood, cord blood, and breast milk.

Abstract

SUMMARY Lead concentrations in maternal blood, umbilical cord blood, and breast milk from 114 women who were not occupationally exposed to lead were determined by graphite atomic absorption spectrophotometry. The mean concentrations of lead in maternal blood, umbilical cord blood and breast milk were 0O7, 0-55, and 0-23 iimol/l, respectively. A significant correlation was observed between maternal and umbilical cord blood (r=063). A lower correlation was noted between maternal blood and breast milk (r=0.29). These results suggest that lead freely crosses the placental barrier from mother to fetus and the transfer of this heavy metal from maternal tissues to breast milk is possible, but the metabolic mechanisms are more complicated. In addition, a longitudinal study was conducted of concentrations of lead in breast milk in nine lactating women. Results suggested no significant change in the content of lead in breast milk during early lactation.The toxicology of lead has been well studied. The contention that excessive absorption of lead in pregnant women may pose a danger to the fetus has also been examined. ' Infants and children are particularly susceptible to the toxicity of lead because of their developing central nervous system, small body size, higher rate of absorption, and tendency to put objects into their mouths.2 Lead also has a higher affinity for fetal haemoglobin.3

Determination of cadmium and lead in human milk

“…The results of lead concentration in milk are between the low levels found in Sweden (Palminger Hallen et al, 1995), Australia (Gulson et al, 2001), China (Li et al, 2000) and Austria (Gundacker et al, 2000) and high levels found in Italy (Guidi et al, 1992), Mexico (Namihiria et al, 1993) and Singapore (Ong et al, 1985). The differences found between different studies conducted in different countries might also be due to different assays employed.…”

Lead in bone: implications for toxicology during pregnancy and lactation.

“…Alternatively, nulliparous women may be more at risk for postmenopausal bone demineralization, although epidemiological studies of postmenopausal osteoporosis have not clearly shown this (18 Lead is also secreted in breastmilk in a range from 0.24 to 35 mcg/dL. External exposures influence breastmilk lead levels, as expected, such that urban populations in general have higher levels than rural populations (19). Lead is found in concentrations higher than those found in plasma at the same time (20).…”

Evaluation of Low Blood Lead Levels and Its Association with Oxidative Stress in Pregnant Anemic Women: A Comparative Prospective Study

“…Pb absorbed by the pregnant mother is readily transferred to the developing fetus [7,8]. There is evidence from animal studies that intrauterine exposure to Pb may disrupt endocrine balance during pregnancy [9,10], and lead to abnormalities of renal structure and function [11], abnormalities of the reproductive system [12], and neurodevelopmental toxicity [13] in offspring.…”