Abstract

Background: Measurement of blood lead (BPb) is the usual method for biomonitoring of persons exposed to inorganic lead.

Aim: To explore the use of salivary lead (SPb) as an alternative.

Methods: BPb and SPb levels were measured in a group of 82 lead exposed adults.

Results: The mean BPb of the workers was 26.6 μg/dl (SD 8.6, range 10–48) and the mean SPb level 0.77 μg/dl, or 3% of the BPb level. As the SPb distribution was skewed, logarithmic transformation was performed to normalise the distribution. A bivariate scattergram of BPb and logSPb (r = 0.41, p = 0.00) had a line of best fit expressed as BPb = 29.7 + 8.95logSPb. The relation of logSPb and BPb was stronger among non-smokers (r = 0.42) compared to smokers (r = 0.3); and among those without a medical condition (r = 0.44). Multiple linear regression analysis (fitting smoking and medical condition into the model) yielded an R of 0.54, and an adjusted R² of 0.26.

Conclusion: The study findings do not support the use of SPb for biomonitoring at BPb levels ranging from 10 to 50 μg/dl.