Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. 
Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. What was reviewed?
This narrative literature review examined the current state of knowledge regarding dietary nickel (Ni) exposure in infants and children, with a focus on both intake from food and measured Ni concentrations in various biological materials (blood, urine, hair, placenta, etc.). The review systematically searched major scientific databases for original, English-language studies published up to April 1, 2025, that evaluated Nickel in children’s food and/or biological Ni levels in children from birth to 18 years. The aim was to assess the risk of exceeding EFSA’s tolerable daily intake (TDI) for Ni, to identify dietary sources most relevant to children, and to summarize associated health effects, especially in the context of increasing food processing and environmental Ni exposure.
Who was reviewed?
The review included 21 studies that investigated infants and children aged 0–18 years from various countries and backgrounds. These studies encompassed a range of dietary habits and environmental exposures, including children living in both urban and industrialized regions, those with selective diets (such as vegetarian or soy-based diets), and subgroups with conditions like atopic dermatitis or anemia. Biological monitoring covered healthy children, neonates, and those with specific health conditions. Some studies also compared children from regions with notably high environmental Ni contamination to those in lower-exposure areas, thus capturing a spectrum of typical and elevated Ni exposures in childhood.
Most important findings
| Aspect | Details / Findings |
|---|---|
| Concern | Nickel in children’s food is rising, with high Ni content in certain foods and pediatric vulnerability. |
| Dietary Sources | Cocoa, chocolate (up to 17 mg/kg), nuts, legumes, soy products; soy-based infant formulas and some baby foods have higher Ni than breast milk. Ni varies by geography, soil, farming, and processing. |
| Exceeding Safe Limits | Children in polluted/industrial areas show elevated urine and hair Ni, associated with oxidative stress markers and sometimes lower birth weight. |
| Biological Evidence | Children in polluted/industrial areas show elevated urine and hair Ni; associated with oxidative stress markers and sometimes lower birth weight. |
| Health Implications | Excess Ni may impair growth, neurodevelopment, hematological status, increase oxidative stress, and exacerbate eczema; strong link between Ni allergy and dermatitis. |
| Gaps & Variability | Ni content varies across foods and between organic/conventional baby foods; no standardized regulatory limits for Ni in infant foods/formulas. |
| Recommendations | Limit processed/canned foods, moderate chocolate/cocoa intake, monitor Ni-rich foods, especially for selective eaters or children with skin conditions; improve labeling, ongoing monitoring, and set regulatory thresholds. |
Key implications
For heavy metal certification programs such as HTMC, this review highlights the urgent need for systematic monitoring and regulation of nickel in foods targeted at infants and children. The findings support the establishment of specific Ni thresholds in high-risk products (e.g., infant formula, ready-to-eat baby foods, chocolate-based products), mandatory reporting of Ni content, and the inclusion of Ni in routine heavy metal screening protocols. The evidence that current exposures can exceed health-based guidance values in a substantial portion of children, especially with modern dietary patterns, argues for proactive risk management, targeted consumer education, and stricter sourcing and manufacturing controls. Furthermore, the review identifies the necessity for more robust epidemiological studies and standardized analytical methods to better understand exposure-risk relationships, inform public health guidance, and refine certification criteria for Ni in children’s food products.
Citation
Dobrzyńska, M., Kaczmarek, K. A., Woźniak, D., Przysławski, J., & Drzymała-Czyż, S. (2025). Nickel exposure from food and levels in children’s blood and tissues: health implications – a narrative literature review. Acta Sci. Pol. Technol. Aliment., 24(3), 315–331. http://doi.org/10.17306/J.AFS.001332
Heavy metals are high-density elements that accumulate in the body and environment, disrupting biological processes. Lead, cadmium, arsenic, mercury, nickel, tin, aluminum, and chromium are of greatest concern due to persistence, bioaccumulation, and health risks, making them central to the HMTC program’s safety standards.
