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Updated: Aug 1, 2026
04:55
Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children
Published on: September 11, 2018
Heavy metal exposure from foods
Environmental Health Perspectives
|December 1, 1975
Summary
The US FDA monitors heavy metals in foods like lead and cadmium. Levels remain stable and below safe limits, indicating consistent food safety.
Area of Science:
- Food safety and toxicology
- Environmental health
- Nutritional science
Background:
- The US Food and Drug Administration (FDA) conducts ongoing surveillance of essential minerals and toxic heavy metals in the food supply.
- Monitoring aims to identify trends in element concentrations and assess dietary exposure.
- Key elements monitored include lead, cadmium, mercury, zinc, arsenic, and selenium.
Purpose of the Study:
- To assess trends in the levels of six elements (lead, cadmium, mercury, zinc, arsenic, selenium) in the American food supply.
- To determine if concentrations of these elements are increasing or decreasing over time.
- To evaluate average dietary intakes of these elements in comparison to established safe levels.
Main Methods:
- Utilized the Total Diet Study (TDS) protocol for food monitoring.
- Collected "market baskets" of typical foods and beverages consumed by 15- to 20-year-old American males.
- Foods were collected seasonally from diverse geographical locations, composited by food class, and analyzed for elemental content.
Main Results:
- Cadmium exhibited the most widespread distribution, while mercury was the most limited among the monitored heavy metals.
- Analytical data indicated that lead levels might be underestimated due to methodological limitations, which did not affect other elements.
- Yearly tabulations revealed no significant year-to-year variations in the levels of these elements in foods.
- Average intakes of lead, cadmium, and mercury were found to be below the tolerable intake levels set by the World Health Organization/Food and Agriculture Organization (WHO/FAO) for adults.
Conclusions:
- Current levels of lead, cadmium, and mercury in the food supply are generally within safe limits for adult consumption.
- The stability of element concentrations suggests consistent food safety regarding these contaminants.
- While tolerable intakes for arsenic and selenium have not been established, any increase in their concentrations would be considered undesirable.
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