Karen Pendergrass is a researcher specializing microbial metallomics and microbiome signatures, with a focus on bridging research and clinical practice. She is the co-founder of several initiatives, including Microbiome Signatures and the Heavy Metal Tested & Certified program, which translate complex science into actionable standards. 
Karen Pendergrass is a researcher specializing microbial metallomics and microbiome signatures, with a focus on bridging research and clinical practice. She is the co-founder of several initiatives, including Microbiome Signatures and the Heavy Metal Tested & Certified program, which translate complex science into actionable standards. What was reviewed?
This review covers the EFSA 2020 update on nickel in food and drinking water, hereafter the EFSA 2020 nickel risk assessment, focusing on toxicity, exposure, and risk characterization using updated benchmark dose guidance and a greatly expanded EU occurrence dataset. The document revises chronic and acute reference points, quantifies dietary exposure across age groups, and proposes risk thresholds relevant to regulatory programs and standards development. It emphasizes a tolerable daily intake of 13 µg/kg bw from a BMDL10 of 1.3 mg/kg bw per day based on increased post-implantation loss in rats, and an acute oral LOAEL of 4.3 µg/kg bw for elicitation of systemic contact dermatitis in nickel-sensitized humans, to be interpreted through a Margin-of-Exposure (MOE) framework, where MOE ≥ 30 indicates low health concern.
Who was reviewed?
EFSA synthesized toxicology, epidemiology, exposure, and occurrence data from EU member states and the peer-reviewed literature. The exposure assessment integrates more than 47,000 analytical results from 24 countries and food consumption surveys spanning infants to very elderly adults. Acute effect characterization relies on controlled human provocation studies in nickel-sensitized volunteers, while chronic endpoints derive from standardized multi-generation rodent studies and benchmark dose modeling.
Most important findings
EFSA set a TDI of 13 µg/kg bw using a BMDL10 of 1.3 mg/kg bw per day for increased post-implantation loss, applying a 100-fold uncertainty factor. Acute effects are dominated by eczematous flare-ups in sensitized individuals; a BMDL could not be robustly derived, so EFSA selected a human LOAEL of 4.3 µg/kg bw and required MOE evaluation, with MOE ≥ 30 regarded as low concern. Mean chronic exposure generally falls at or below the TDI for adolescents and adults, but the 95th percentile exceeds the TDI in many infant, toddler, and other-children surveys, driven largely by grains and grain-based products, complemented by legumes, nuts and oilseeds, vegetables, and chocolate products. Acute high-percentile exposure is often linked to beans, coffee, ready-to-eat soups, chocolate, and breakfast cereals. A specific empty-stomach water scenario produced low acute concern (MOE 120 for tap; 55 for bottled). EFSA highlighted higher oral bioavailability in fasted conditions and substantial inter-individual variability. Overall, EFSA concluded that acute dietary nickel raises concern for typical high-end intakes and that chronic exposure may be of concern for young children at the upper tail of intake distributions.
Key implications
For an industry certification scheme, the EFSA 2020 nickel risk assessment provides actionable anchors. First, HMTC should adopt EFSA’s TDI of 13 µg/kg bw as the chronic health-based benchmark and use MOE-based screening for acute risk, flagging food categories where realistic acute MOEs for sensitized consumers fall below 30. Second, prioritization should focus on major exposure contributors: grains and grain-based products, legumes and nuts, selected vegetables, cocoa and chocolate, and certain beverages. Product standards and supplier controls should be calibrated to lower distribution tails of product nickel content, not just means, since the 95th percentile dietary exposure drives exceedances in toddlers and other children. Third, communication and labeling can mitigate acute risks in nickel-sensitized populations, especially for high-nickel products that are often consumed on an empty stomach. Finally, given EFSA’s uncertainty analysis, HMTC should encourage data generation on nickel bioavailability under fed conditions, monitor migration from food contact materials where quality is variable, and consider advisory limits for category-specific maximum levels and for vulnerable groups, aligning with MOE criteria for acute risk management.
Citation
EFSA Panel on Contaminants in the Food Chain (CONTAM). Update of the risk assessment of nickel in food and drinking water.EFSA Journal. 2020;18(11):6268. doi:10.2903/j.efsa.2020.6268.
Nickel is a widely used transition metal found in alloys, batteries, and consumer products that also contaminates food and water. High exposure is linked to allergic contact dermatitis, organ toxicity, and developmental effects, with children often exceeding EFSA’s tolerable daily intake of 3 μg/kg bw. Emerging evidence shows nickel crosses the placenta, elevating risks of preterm birth and congenital heart defects, underscoring HMTC’s stricter limits to safeguard vulnerable populations.
Nickel is a widely used transition metal found in alloys, batteries, and consumer products that also contaminates food and water. High exposure is linked to allergic contact dermatitis, organ toxicity, and developmental effects, with children often exceeding EFSA’s tolerable daily intake of 3 μg/kg bw. Emerging evidence shows nickel crosses the placenta, elevating risks of preterm birth and congenital heart defects, underscoring HMTC’s stricter limits to safeguard vulnerable populations.
Nickel is a widely used transition metal found in alloys, batteries, and consumer products that also contaminates food and water. High exposure is linked to allergic contact dermatitis, organ toxicity, and developmental effects, with children often exceeding EFSA’s tolerable daily intake of 3 μg/kg bw. Emerging evidence shows nickel crosses the placenta, elevating risks of preterm birth and congenital heart defects, underscoring HMTC’s stricter limits to safeguard vulnerable populations.
Nickel is a widely used transition metal found in alloys, batteries, and consumer products that also contaminates food and water. High exposure is linked to allergic contact dermatitis, organ toxicity, and developmental effects, with children often exceeding EFSA’s tolerable daily intake of 3 μg/kg bw. Emerging evidence shows nickel crosses the placenta, elevating risks of preterm birth and congenital heart defects, underscoring HMTC’s stricter limits to safeguard vulnerable populations.
