Lead Over-absorption in a Population of Oxy-gas Burners

PLINY (AD 23-79) observed that in the second century BC the ancients painted their ships with native ceruse (white lead), that lead poisoning was known in his day and that the workers in lead products tied up their faces in loose bags lest they should inhale the pernicious dust1. In a survey of 228 men in nine shipbreaking yards in Scotland and NE England, McCallum2 focused attention on the health hazard resulting from burning lead-painted metal with a high temperature flame. He found 36% of the burners with a haemoglobin content less than 12.5 g per 100 ml of whole blood. In this operation, in which oxy-gas torches have been used at the work face, temperatures are in the region of 3,000–3,500° C. Iron melts at 1,535° C and is found in vapour form at 3,000° C. Lead melts at 328° C and boils at 1,740° C. This produces a risk of excessive exposure in compartments and between decks of ships, of which lead from paintwork is the principal risk3. In the breathing zone of the burner, with maximum concentrations of fume at torch level, may also be found zinc (zinc metal fume fever), copper from piping and cadmium from protective coatings4.