Do worker's chronically exposed to lead have leukocytosis?

In the following study, we examined the possible relationship between acute and chronic measures of lead exposure and total white cell blood counts in 94 workers in a lead-battery plant who were followed-up from 1980 to 1993. Acute measures of lead exposure included blood lead (PbB), and zinc protoporphyrin levels (ZPP) measured concomitantly with the total white blood count, and a measure of chronic exposure was represented by average blood lead levels over the follow-up period. Of the 947 white blood cell counts, leukocytosis was found in 92 (9.7%), but there was no higher proportion of leukocytosis in the groups with higher PbB or ZPP results. Of those where a smoking history was recorded, none of the 188 non-smokers had leukocytosis, compared to 78 of 590 smokers (0 vs. 13.2%, respectively, P < 0.05). The white count was not significantly correlated with ZPP, PbB or the average PbB of the workers. We conclude that lead exposure does not influence the white blood cell count in battery workers, and that the cause of an elevated white count in such worker's is probably due entirely to a history of smoking. Further studies are warranted to substantiate our findings.