The influence of dietary citrate on the absorption and retention of orally ingested lead.

The influence of dietary citrate on the toxicity of orally ingested lead was investigated in male weanling mice. Twenty-four animals were divided into three equal groups. Group 1 served as controls, groups 2 and 3 were given 20 micrograms lead (as lead acetate) per g/diet, group 3 also received 4% sodium citrate in the diet. After 5 weeks, blood and tissue lead levels were measured. All mice given lead-supplemented diets had higher concentrations of lead in blood, liver, kidney, brain and bone than the control group, but the increase was significantly greater in the group given 4% sodium citrate in the diet. This work demonstrated that dietary citrate at levels which can be present in food significantly increases lead toxicity.