Statement on tolerable weekly intake for cadmium
The Panel on Contaminants in the Food Chain of the European Food Safety Authority (CONTAM Panel) was asked by the European Commission to confirm whether the current tolerable weekly intake (TWI) of 2.5 µg/kg body weight (b.w.) for cadmium is still considered appropriate or whether any modifications are needed in view of the provisional tolerable monthly intake (PTMI) of 25 µg/kg b.w. established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 2010. Both assessments used the same epidemiological dataset and have two primary components, a concentration-effect model that relates the concentration of cadmium in urine to that of beta-2-microglobulin (B2M), a biomarker of renal tubular effects, and a toxicokinetic model that relates urinary cadmium concentration to dietary cadmium intake. The following methodological differences were identified: i) the identification of the reference point on the basis of the urinary cadmium and the B2M concentration data; ii) the statistical approach to account for the variability and uncertainty of the biomarker of exposure (urinary cadmium concentration) and the biomarker of response (B2M concentration) in the concentration-effect model; and iii) the methodology for transforming urinary cadmium concentrations into dietary intake values.
Following an evaluation of the two approaches, the CONTAM Panel concluded that the approach adopted for its previous opinion on cadmium in food was appropriate and hence the current TWI for cadmium of 2.5 µg/kg b.w. was maintained.