Overview
Siddiqui and colleagues measured lead and cadmium by graphite furnace atomic absorption in 54 whole hen eggs (yolk and white mixed) from nine poultry farms around Karachi, collected between 2004 and 2007. Lead was high relative to other countries, with the highest values from Farm No. 3; cadmium was low.
Key numbers
- Lead, 54 eggs: mean 0.2830 µg/g (SD 0.2427), median 0.1827, range 0.0269 to 1.0557 µg/g (Table 5, p. 97).
- Cadmium, 54 eggs: mean 0.0032 µg/g (SD 0.0020), range 0.0010 to 0.0122 µg/g (Table 5, p. 97).
- Farm No. 3: lead 0.4701 to 1.0557 µg/g (Table 6, p. 97).
Methods (brief)
Each egg was homogenized, digested with nitric acid and hydrogen peroxide, and read by Zeeman graphite furnace AAS. Spike recoveries were 98 to 99 percent; no LOD is stated and the reference materials are not identified. The DOI is not printed in the PDF.
Evidence Fitness
Moderate sample from one region with recovery checks. Table 6 repeats the lead values in the farm 9 cadmium row, and the Table 3 summary cannot be reconciled with Table 5, so those were flagged or left out. Eggs are an ingredient proxy for custard, so that page is not linked.