Neurochemical effect of lead exposure: a study on catecholamine metabolism

In an attempt to examine the neurochemical changes of lead exposure, a study was conducted on 106 lead workers and a control group of 25 nonexposed workers. The urinary excretion of major catecholamine metabolites, homovanillic acid (HVA), and vanillylmandellic acid (VMA) were measured. Workers exposed to lead had a mean blood lead concentration of 43.2 micrograms/100 ml, whereas the concentration for workers not exposed to lead was 12.7 micrograms/100 ml. Urinary HVA was significantly elevated in the exposed group when compared with controls (p less than 0.01). HVA was also found to be associated with an increase of lead in blood. Although not statistically significant, the VMA excretion was also noted to be moderately elevated; however, it is recognized that the present study was unable to establish a highly significant dose-response relationship between lead exposure and HVA excretion, as has been reported earlier in lead-poisoned children.