Contribution of lead in wine to the total dietary intake of lead in humans with and without a meal: a pilot study

Several studies have suggested that intake of alcoholic beverages contributes significantly to the concentration of lead in blood. We have undertaken a pilot case-control study using high-precision lead isotopes to evaluate the contribution to blood lead when a normal quantity of wine is consumed with a meal and compared this with consumption under fasting conditions. White wine dosed with a 207 Pb tracer was consumed with a meal and under fasting conditions, and blood, urine and faeces were monitored for up to 4 months. Approximately equal proportions of unspiked red and white wine were consumed over the 4 months by the subject and a female subject residing in the same household. The blood lead concentration of the case subject was 4.1 μg dl -1 and 3.4 μg dl -1 in the control subject. No increase in the concentration of lead in blood for the wine consumed with a meal was detectable, but there was an approximately 6% increase in blood lead concentration for wine consumed under fasting conditions. When consumed with a meal, the percentage absorption at 24 h was only 2.3%, compared with approximately 34% under fasting conditions. For the consumption of wine with a meal, the half-life for uptake of lead from the wine was 8.6± 1.7 h with a rate constant of 0.081 ± 0.016/h and the clearance of lead from blood had a half-life of 23 days with a rate constant of 0.21/week. For consumption of wine under fasting conditions, the half-life was 5.4 ± 1.5 h with a rate constant of 0.13 ± 0.04/h. An additional control was possible because of marked difference in the ratios of the white wine compared with the prevailing Australian isotopic signature. Over the 4 months of the trial, there was no detectable change in the other isotopic ratios in both subject and control, confirming the minimal uptake of lead from wine when consumed with food.