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 comprehensive review, focusing on heavy metal exposure in young children, critically appraises the current state of knowledge regarding dietary intake of toxic elements, specifically arsenic, lead, cadmium, and mercury, and their health impacts on early childhood. The review synthesizes findings from global epidemiological studies, food monitoring programs, and laboratory analyses to assess the magnitude, sources, and consequences of dietary exposure to these toxic elements. It also examines the methodologies used for dietary assessment, biomarker evaluation, and exposure modeling, highlighting the challenges in accurately quantifying toxicant intake and linking it to health outcomes. The review emphasizes the variability in contamination across foods, regions, and preparation methods, and underscores the urgent need for standardized, up-to-date, and comprehensive data to inform risk assessments and regulatory actions. It further identifies critical gaps in monitoring practices, analytical techniques, and causal inference models that hinder the ability of regulatory programs, such as heavy metal certification, to effectively protect child health.
Who was reviewed?
The review encompasses a wide array of global populations, with a focus on infants and young children who are uniquely vulnerable to heavy metal exposure due to higher per-body-weight intake and immature detoxification mechanisms. It includes data from national surveys (e.g., NHANES in the United States, ENSANUT in Mexico), targeted cohort studies in countries like Bangladesh, Spain, and China, and food contamination reports from regulatory agencies and independent organizations. Both breastfed and formula-fed infants, as well as children consuming commercial and homemade foods, are considered. The review also highlights special population groups, such as pregnant women, children with allergies or restricted diets, and those in regions with heightened environmental contamination. By synthesizing findings across diverse geographical, cultural, and socioeconomic contexts, the review provides a holistic picture of the heavy metal exposure landscape in early childhood.
Most important findings
| Critical Points | Details |
|---|---|
| Prevalence and Sources of Exposure | Toxic elements—arsenic, lead, cadmium, and mercury—are frequently detected in infant foods globally, with commercial products and homemade foods both contributing to intake. Contamination arises during crop cultivation, food processing, packaging, and preparation. Water, breast milk, and formula are additional sources. |
| Health Impact Evidence | Even low-level exposures to toxic elements in early childhood can affect neurodevelopment, growth, and cognitive function, with societal costs being substantial. Dietary exposure is linked to increased biomarker levels and adverse outcomes, but causal links remain under-researched due to methodological limitations. |
| Data Gaps and Methodological Challenges | Existing food contaminant databases are outdated and incomplete, especially for infant foods and diverse diets. Dietary assessment methods vary in accuracy, with single recalls insufficient for individual risk assessment. Biomarker data are rarely collected in very young children, limiting exposure-health linkage studies. |
| Analytical and Monitoring Limitations | Inductively coupled plasma mass spectrometry (ICP-MS) is considered the gold standard for measuring trace elements, but its adoption is inconsistent worldwide. Inadequate detection limits and lack of standardized laboratory protocols impede data comparability and integration. |
| Exposure Modeling and Causal Inference | Deterministic models often underestimate exposure due to database mismatches. Probabilistic models are more accurate but resource-intensive. Mixture effects—combined exposures to multiple toxicants—are rarely modeled, though they may amplify health risks. Nutritional status can modify toxicant absorption and risk. |
| Regulatory and Policy Implications | Current regulatory actions, such as the US FDA’s Closer to Zero initiative, are progressing slowly and may not prompt timely interventions. Systematic monitoring and harmonized methodologies are lacking, hindering effective heavy metal certification and public protection. |
Key implications
For heavy metal certification programs, this review demonstrates the necessity of regular, comprehensive monitoring of both commercial and homemade foods, including water and supplements. It highlights the need for up-to-date contaminant databases, adoption of gold-standard analytical methods like ICP-MS, and the development of probabilistic, mixture-focused exposure models. The review underscores that regulatory timelines must accelerate, and multi-sectoral collaboration is essential for protecting vulnerable populations, especially young children.
Citation
Kordas, K., Cantoral, A., Desai, G., Halabicky, O., Signes-Pastor, A.J., Tellez-Rojo, M.M., Peterson, K.E., & Karagas, M.R. (2022). Dietary Exposure to Toxic Elements and the Health of Young Children: Methodological Considerations and Data Needs. The Journal of Nutrition, 152(10), 2572–2581. https://doi.org/10.1093/jn/nxac185
Arsenic is a naturally occurring metalloid that ranks first on the ATSDR toxic substances list. Inorganic arsenic contaminates water, rice and consumer products, and exposure is linked to cardiovascular disease, cognitive deficits, low birth weight and cancer. HMTC’s stringent certification applies ALARA principles to protect vulnerable populations.
Lead is a neurotoxic heavy metal with no safe exposure level. It contaminates food, consumer goods and drinking water, causing cognitive deficits, birth defects and cardiovascular disease. HMTC’s rigorous lead testing applies ALARA principles to protect infants and consumers and to prepare brands for tightening regulations.
Cadmium is a persistent heavy metal that accumulates in kidneys and bones. Dietary sources include cereals, cocoa, shellfish and vegetables, while smokers and industrial workers receive higher exposures. Studies link cadmium to kidney dysfunction, bone fractures and cancer.
Cadmium is a persistent heavy metal that accumulates in kidneys and bones. Dietary sources include cereals, cocoa, shellfish and vegetables, while smokers and industrial workers receive higher exposures. Studies link cadmium to kidney dysfunction, bone fractures and cancer.
