RESUMO
As part of a cohort study of the effects of chronic exposure to lead on pregnancy outcome and child development, lead concentrations in the umbilical cord and placental tissues (body and membranes) from 9 late fetal deaths, 23 preterm births, and 18 births associated with premature rupture of the amniotic membranes were compared with the lead concentrations in the tissues obtained at 22 normal births. Modest elevations in lead concentration were found in the placental body of late fetal deaths (stillbirths) and preterm births as well as in the cord tissue associated with preterm births and premature rupture of membranes. The geometric mean lead concentration in the membranes from late fetal deaths was 2.73 micrograms/g of dry tissue (95% confidence limits 0.69-10.8), which was 3.5 times higher than the mean found in normal births (0.78 micrograms/g, 95% confidence limits 0.61-1.00). The concentration in the membranes of preterm births was also significantly high, being 1.24 micrograms/G (0.91-1.67). Low correlations of membrane and antenatal blood lead concentrations suggest that other factors in addition to exposure to environmental lead may influence the amount of lead accumulated in the placental membranes.
Assuntos
Indústria Química , Membranas Extraembrionárias/metabolismo , Intoxicação por Chumbo/metabolismo , Placenta/metabolismo , Resultado da Gravidez , Cordão Umbilical/metabolismo , Estudos de Coortes , Exposição Ambiental , Feminino , Morte Fetal/metabolismo , Ruptura Prematura de Membranas Fetais/metabolismo , Humanos , Trabalho de Parto Prematuro/metabolismo , Gravidez , Controle de QualidadeRESUMO
Capillary blood lead levels were investigated in a sample of 513 children of preschool age who were drawn from an industrial working-class region of Adelaide. The geometric mean lead level was 16.3 micrograms/dL. Fourteen children (2.7%) had a blood lead level of at least 30 micrograms/dL, which is designated by the National Health and Medical Research Council as "the level of concern". Boys tended to have higher lead levels than did girls, and children who lived closer to the inner city generally had higher levels than did those who lived further away. Compared with most other Australian findings, the blood lead levels in this study tended to be high. We suspect that the age groups that were studied, and the industrial urban quality of the region that was included, would have had an important bearing on this finding. However, the proportion of children with elevated lead levels in this study did not seem high when compared with US data for children in a comparable age range.
Assuntos
Chumbo/sangue , Austrália , Capilares , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fatores Socioeconômicos , População UrbanaRESUMO
The magnesium content of duodenal mucosa was estimated in biopsy specimens from 50 patients, 43 of which had normal mucosal histopathology. There was no significant difference in the mean mucosal magnesium content of those speciments with normal and abnormal histopathology and overall the mean value was 30.9 mmol/kg dry weight of tissue, but there was a wide spread of values. The concentration of magnesium in plasma and duodenal fluid was also determined. There was no significant correlation between duodenal mucosal magnesium content and plasma magnesium concentration. However, there was a weak but statistically significant correlation between magnesium content in duodenal fluid and duodenal mucosa (r = 0.54, p less than 0.001).
