At the request of the Hellenic Food Authority, the European Food Safety Authority’s (EFSA’s) Panel on Contaminants in the Food Chain (CONTAM Panel) has issued a scientific opinion on the public health risks associated with the presence of nickel (Ni) in food—especially vegetables—and drinking water. Citing the established tolerable daily intake (TDI) of 2.8 µg Ni/kg body weight (bw) per day, the CONTAM Panel concluded that chronic dietary exposure to nickel represents a concern for the general population and that consumers already sensitized to nickel through dermal contact may develop eczematous flare-up skin reactions at the current levels of acute dietary exposure levels.

The CONTAM Panel relied on a total of 18,885 food samples and 25,700 drinking water samples to estimate dietary exposure to nickel, finding that the following food groups were the main contributors across age categories: (i) grain and grain-based products; (ii) non-alcohol beverages (except milk-based beverages); (iii) sugar and confectionary; (iv) legumes, nuts and oilseeds; and (v) vegetable and vegetable products—with milk and dairy products an additional contributor in young populations. In particular, the panelists reported that “the relatively high consumption of chocolate and chocolate-based products made ‘sugar and confectionary’ one of the main contributors” of dietary nickel for adolescents and other children, while the consumption of cocoa beverages and coffee made “non-alcoholic beverages” a main contributor for young and adult populations, respectively.

Toddlers and other children reportedly showed the highest chronic and acute dietary exposure to nickel. According to the panel, which reported that mean acute dietary exposure in the young population ranged from 3.4 to 14.3 µg Ni/kg bw per day, “[t]he mean chronic dietary exposure to Ni across the different dietary surveys and age classes, ranging from 2.0 (minimum LB, ‘Elderly’) to 13.1 µg Ni/kg bw per day (maximum UB, ‘Toddlers’) is close to the TDI or above it particularly when considering the young age groups (‘Infants,’ ‘Other Children,’ ‘Toddlers,’ and ‘Adolescents’).” In addition, EFSA noted that “[t] he 95 percentile dietary exposure ranging from 3.6 (minimum LB, ‘Elderly’) to 20.1 µg Ni/kg bw per day (maximum UB, ‘Toddlers’) is above the TDI for all age groups.”

“The CONTAM Panel concluded that the exposure via the diet likely represents the most important contribution to the overall exposure to Ni in the general population,” states the scientific opinion. “The CONTAM Panel noted the need for mechanistic studies to assess the human relevance of the effects on reproduction and development observed in experimental animals and for additional studies on human absorption of Ni from food, for example in combination with duplicate diet studies.”