Overview
Trujillo-Cruz and colleagues measured total mercury in 60 cans of tuna in oil from the three most widely sold brands in Quito, Ecuador, using a direct mercury analyzer, and estimated exposure and weekly intake limits. Brand means ranged from 0.22 to 0.63 mg/kg, and the middle-priced brand had individual cans up to 0.89 mg/kg, above the Ecuadorian limit of 0.50 mg/kg. Only mercury was measured. The PDF is the unedited Article in Press version.
Key numbers
- Brand A (lowest price): 0.22 ± 0.10 mg/kg, range 0.05 to 0.40 (Table 1, p. 21).
- Brand B (intermediate price): 0.63 ± 0.10 mg/kg, range 0.48 to 0.89 (Table 1, p. 21).
- Brand C (highest price): 0.36 ± 0.15 mg/kg, range 0.14 to 0.61 (Table 1, p. 21).
Methods (brief)
The packing oil was removed, the edible portion homogenized and freeze-dried, and about 40 mg analyzed by thermal decomposition and amalgamation AAS (DMA-80, EPA 7473). Blanks, replicates and DORM-4 reference material were run, and accuracy was reported as within AOAC limits without printing the values.
Evidence Fitness
Twenty cans per brand over a year with reference-material QA: good direct evidence for mercury in tinned-fish (canned tuna). The weight basis of the results is not stated even though samples were freeze-dried, and the manuscript is not yet the final edited version. Methylmercury was assumed, not measured.