ABSTRACT
OBJECTIVE: To identify exposure factors contributing to lead poisoning in school children from Mexico City. MATERIAL AND METHODS: Cross-sectional study of 340 children. A convenience sample of schools and a random sample of children were selected. A questionnaire was filled out and venous blood samples were taken. Lead levels were measured by atomic absorption spectrophotometry. Statistical analysis consisted of comparison of means using Student's t test and ANOVA. Multiple linear regression was used for multivariate analysis. Logarithmic transformation of lead blood levels were used to account for their non-normal distribution. RESULTS: Geometric means for private and public schools were: GM = 8.76 micrograms/dl, 95% CI = 9.1-10.5; GM = 11.5 micrograms/dl, 95% CI = 9.4-13.5. Lead levels were higher among children from public schools who are male, between 6 and 8 years of age, in first and second grade, whose mothers have a profession, who use glazed earthenware utensils, and who live near glazed earthenware shops or factories. CONCLUSIONS: Exposure predictors of lead blood levels are: being between 6 and 8 years of age, having a professional mother, using glazed earthenware utensils, living near glazed earthenware shops or factories, and studying the second grade of elementary school.
Subject(s)
Environmental Exposure , Lead/blood , Child , Cross-Sectional Studies , Female , Humans , Male , Mexico , Regression Analysis , Schools , Surveys and QuestionnairesABSTRACT
The Pelger-Huët anomaly (PHA) and the hereditary elliptocytosis (HE) are alterations affecting leukocytes and erythrocytes, respectively. Most of the affected individuals do not present clinic manifestations and are casually detected in the laboratory. The PHA and HE were described related to other hereditary and congenital conditions, but rarely have been found in the same individual. In this paper are reported discovery of the PHA and HE combined both in sister and brother, with global delay of development and peculiar physical characteristics. Blood smears of both showed an increase of bilobed neutrophils and elliptic erythrocytes. The family study showed two more members of the mother's branch affected with HE. The PHA could not be found in the parents, nor the other members of both branches. The early deaths or in uterus of three sibs of the propositus are appointed. The absence of the PHA in both parents of the affected individuals,--without discarding the illitimacy possibility--, can be explained by an incomplete genetic penetrance. The early or in uterus deaths of three sibs of the propositus seems possible that in some cases the combination of PHA and HE could be lethal. Possibly in Mexico this may be the first report of the presentation of the PHA and HE simultaneously in the same individual.
