Schaefer et al. 2020 — Cadmium: Mitigation strategies to reduce dietary exposure
This peer-reviewed concise review, authored by FDA/CFSAN scientists, synthesises the scientific basis for cadmium in the food supply and evaluates mitigation strategies across the full supply chain from agronomic production through processing to consumer preparation. Published in the Journal of Food Science (Vol. 85, Iss. 2, 2020), the paper draws on the 2011 JECFA review, the 2009 and 2011 EFSA scientific opinions, and the FDA Total Diet Study 2014–2016 to provide US-centric concentration data. Key findings: diet is the dominant cadmium exposure pathway (approximately 90% of non-occupational, non-smoking exposure); leafy vegetables, root crops, cereals, and grains are the primary dietary contributors; and the most impactful mitigation lever is reducing initial plant uptake through soil pH management, cultivar selection, and fertiliser choice, rather than downstream processing interventions. The paper explicitly identifies data gaps and recommends commodity-specific codes of practice.
Key numbers
FDA Total Diet Study 2014–2016 — top 10 foods by mean lower-bound Cd concentration (µg/kg wet weight):
- Sunflower seeds: 375 µg/kg
- Boiled spinach: 117 µg/kg
- Potato chips: 93 µg/kg
- Leaf lettuce: 62 µg/kg
- Iceberg lettuce: 54 µg/kg
- Peanut butter: 53 µg/kg
- Shredded wheat cereal: 51 µg/kg
- Dry roasted peanuts: 45 µg/kg
- French fries: 44 µg/kg
- Cooked liver: 38 µg/kg
JECFA 2011 — mean Cd concentrations in food categories (higher-Cd groups, mg/kg):
- Crustaceans, mollusks: 0.1–4.8 mg/kg
- Organ meats (liver, kidney): 0.1–4.8 mg/kg
- Vegetables, nuts and oilseeds, spices, coffee, tea, cocoa: 0.1–4.8 mg/kg (range covers all these categories together)
Dietary exposure estimates:
- Adults: diet accounts for approximately 90% of cadmium exposure (non-smokers)
- Children aged 1–6 years (US TDS 2014–2016): mean Cd exposure 0.38–0.44 µg/kg bw/day; grains, mixed dishes, and vegetables account for most exposure
- Children aged 0.5–12 years (JECFA 2011 global): mean Cd 2.7–12.9 µg/kg bw/month (AU, EU, US data)
- Vegetarians estimated to have threefold higher relative Cd intake than nonvegetarians
- Children estimated to have twofold higher relative Cd intake than adults (EFSA)
Cd absorption after dietary exposure: estimated 3–5% in adults; some studies report intestinal absorption up to 44%; further research needed especially for children
Cd biological half-life: estimated 10–33 years in humans
Non-polluted agricultural soils: Cd typically < 1 µg/g (range 0.06–1.1 mg/kg), average 0.27 mg/kg; polluted areas up to 800 µg/g
Methods (brief)
Concise review (not a systematic meta-analysis). Primary source synthesis from JECFA 2011, EFSA 2009/2011/2014, ATSDR 2012, and the FDA TDS 2014–2016 dataset (Spungen, 2019). No original measurements. Authors are FDA CFSAN staff; work supported through Oak Ridge/DOE-FDA interagency agreement. Published in a peer-reviewed journal (Wiley/IFT). Evidence tier elevated to A because (a) FDA-affiliated authorship with institutional review, (b) published peer-reviewed synthesis of primary government data, and (c) direct relevance to FDA Toxic Element Working Group efforts.
Implications
Certification: The FDA TDS data provide the most rigorous US-market Cd concentrations across common ingredients. Peanut butter at 53 µg/kg (53 ppb) and sunflower seeds at 375 µg/kg (375 ppb) are directly usable in contamination-profile updates for those ingredient pages. The review’s mitigation hierarchy (soil pH > cultivar selection > fertiliser management > processing > consumer diet) aligns directly with the wiki’s Mitigation options section ordering for ingredient pages.
Courses: The exposure hierarchy (soil → plant → human), the factors modulating bioavailability (iron/zinc/calcium deficiency amplifying absorption), and the population-specific risk (children, women of childbearing age, vegetarians) are core cadmium course content. The EFSA and JECFA TWI/PTWI benchmark comparisons provide regulatory context.
App: Concentration anchors from TDS 2014–2016 for Cd in sunflower seeds (375 ppb), spinach (117 ppb), peanut butter (53 ppb), lettuce (62 ppb dry-weight caveats may apply), shredded wheat (51 ppb), potatoes/fries (44–93 ppb), and peanuts (45 ppb). These are lower-bound estimates (non-detects set to zero), so actual means may be higher.