An assessment of the laboratory tests used to monitor the exposure of lead workers

Abstract

Hæger-Aronsen, Birgitta (1971). Brit. J. industr. Med., 28, 52-58. An assessment of the laboratory tests used to monitor the exposure of lead workers. In order to ascertain which laboratory tests are valuable for the monitoring of lead workers, 168 men exposed to lead at eight factories were examined for lead (Pb), protoporphyrin (PP), haemoglobin (Hb), and basophilic stippling of red cells (BSC) in the blood and for δ-aminolevulinic acid (ALA) and coproporphyrin (CP) in the urine.

The counting of BSC and the determination of PP in the blood are both complicated and time-consuming procedures. As they do not offer any particular advantages in the detection or evaluation of lead poisoning they are considered as less suitable.

The concentration of Pb in the blood reflects the absorption of the lead but not its effect. This is certainly a disadvantage.

A highly significant, negative correlation was found between Hb in the blood and ALA in the urine.

The concentrations of ALA and CP in the urine are both good indicators of the degree of lead poisoning. The former is more specific and more sensitive and is therefore considered the most suitable test for the biochemical monitoring of lead workers. A simple, safe, and quick method is recommended.

Determinations of Hb and Pb in the blood may be useful as supplementary methods in the evaluation of lead poisoning but are, in our experience, only seldom needed.