Relationship between blood lead concentrations and dietary lead intake in infants: the Glasgow Duplicate Diet Study 1979-1980.

In 1979-1980 a duplicate diet study of 131 infants was carried out in Glasgow where the water was plumbosolvent and water lead levels were known to be often above 100 micrograms/l. The main aim of the study was to establish the form of the relationship between water lead, dietary lead and blood lead in infants. The study was designed so that there was a balanced number of measurements over a wide range of lead intakes. Blood lead concentrations of the mothers were measured as well as those of the infants. Results from the study showed that high values of lead in water, diet and blood were closely associated with each other. Blood lead concentrations appeared to have non-linear (cube root) relationships with water lead concentrations and dietary intakes of lead, with steadily smaller increases in blood lead as amounts or concentrations of ingested lead increased. However, infants who were wholly breast fed showed a much weaker effect of water lead on blood lead. Some diets had much higher lead concentrations than the water lead concentration would have suggested because they had been made up with water from the hot tap (rather than the kitchen cold water tap).