ABSTRACT
The mean lead levels in the maternal blood, cord blood, breast milk and placental tissue, were 0.63 mumol/L (13.2 micrograms/dL), 0.33 mumol/L (6.90 micrograms/dL), 4.74 micrograms/L and 0.86 mumol/kg (17.85 micrograms/100 g) respectively for 165 parturient women occupationally non-exposed to lead in 2 hospitals in Shanghai. No significant difference was found between maternal age groups for these indicators. However, the lead levels in the cord blood and breast milk increased with the lead level in the maternal blood, with coefficient of correlation of 0.714 (P < 0.0001) and 0.353 (P < 0.01) respectively. The mean concentration of lead in breast milk for 12 occupationally lead exposed women was 52.7 micrograms/L, which was almost 12 times higher than that for the occupationally non-exposed population. These results suggested that transfer of lead via placenta prenatally and breast milk postnatally were possible and might pose a potential health hazard to the fetuses and the neonates.
Subject(s)
Environmental Exposure , Environmental Pollutants/pharmacokinetics , Lead/pharmacokinetics , Milk, Human/chemistry , Adult , Female , Fetal Blood/chemistry , Humans , Maternal-Fetal Exchange , Placenta/chemistry , PregnancyABSTRACT
In epidemiological investigations, the validity and reliability of data under different ways of collection might not be consistent. In order to evaluate the consistency of data collected from cases themselves or from their surrogates (for example, the spouse) through answering the same questionnaire, at personal interview, was carried out among 50 cases of lung cancer and their surrogates respectively. Other than the item starting age of smoking by a paired-t test, the results showed that between the two groups of quantitative data sources, the overall consistent rate was 84.1% and the differences were not significant (P < 0.05). When Kappa consistency test was used to the count variables, an average consistent rate of 87.8% was noticed, but P values were less than 0.001 for all items. Results from this study were quite similar to those with have been published abroad and suggested that it is credible to collect data from surrogates when dead cases were selected as research subjects.
