same vicinities, quoted in the official report of environmental
authorities2.
Statistical methods
Statistical analysis was performed with Stata 8 (STATA
Corp., College Station, TX). All results were subject to a
general descriptive analysis. B-Pb values presented log
normal distributions and were log transformed to fit
normal distribution. Pearson correlations and ANOVA
between groups of demographic variables were performed
to evaluate their association or differences and
when needed, they were evaluated with linear regression
models.