Overview
Batool and colleagues compared the proximate composition and the calcium, iron, zinc, copper, lead, nickel and cadmium content of four fresh animal milks (cow, buffalo, camel, goat) and six tetra pack branded milks bought in Faisalabad, Pakistan. Metals were measured by flame AAS after nitric and perchloric acid digestion. Each product is a single sample with duplicate determinations.
Key numbers
- Fresh camel milk (S3): lead “0.667±0.28” ppm, the lowest detected lead among the milks; nickel and cadmium not detected (Table 3).
- Fresh cow milk (S1): lead “3.17±0.38” ppm; fresh goat milk (S4) “3.167±0.41” ppm; fresh buffalo milk (S2) “2.184±0.29” ppm (Table 3).
- Tetra pack milks: lead not detected to “2.33±0.34” ppm; nickel and cadmium not detected in any milk (Table 3).
- Camel milk zinc “11.16±0.4” ppm and iron “15.33±0.29” ppm (Table 3).
Methods (brief)
One mL of milk was digested with concentrated nitric acid and then perchloric acid, diluted to 20 mL and read by flame AAS (Hitachi Z-8200) under AOAC conditions. Values are mean ± SEM of duplicate determinations, in ppm without a stated mass or volume basis. No detection limit, certified reference material or recovery is reported.
Evidence Fitness
Weak. There is one sample per milk type, no detection limit and no accuracy check, and the lead values (0.667 to 3.17 ppm) are far higher than typical milk values, which suggests an analytical problem with flame AAS at these levels. The paper quotes two conflicting lead limits (1000 ppb in the introduction, 0.02 ppm in the Table 3 reference row). It measures camel milk directly, but a single market sample cannot represent camel milk in Pakistan.