In total, 45 adult women in Manila, the Philippines, volunteered to participate in the study by offering peripheral blood samples and 24-h total food duplicate samples.

In addition, they offered raw (uncooked) rice as well as wheat flour and maize starch from the kitchen.

Lead (Pb) and cadmium (Cd) in food duplicates and blood samples were measured by inductively coupled plasma mass spectrometry after homogenization (when necessary) and wet-ashing.

The consumption of rice, wheat and maize was calculated by weighing each food item in the duplicates taking advantage of the food composition tables.

The dietary exposure level of the women was 11 mug Pb/day and 14 mug Cd/day, and the levels of Pb and Cd in their blood were 37 ng Pb/ml and 0.47 ng Cd/ml.

There is a subtle age-dependent increase in the dietary burden of Pb and Cd and also in blood levels of Pb and Cd.

Rice accounted for 18 and 21% of dietary Pb and Cd intake, respectively and cereals (i.e. rice, wheat and maize in combination) accounted for 24% both for Pb and Cd.

The calculation from the published data on air quality in Manila suggested that another and yet a greater source of Pb burden was Pb in atmospheric air which may account for 85% of total Pb uptake, whereas the amount of Cd in air was quite small (i.e.<10% of the total uptake).