Testing Food and Drugs for Heavy Metals
Some heavy metals are toxic at extremely low levels, and new elemental analyzers improve testing
Scientists apply elemental analyzers in a wide range of fields, including testing for contaminants in water, food, drugs, and nutritional supplements. Most important, elemental analysis applies to “things consumed by humans, mainly for safety reasons,” says Haihan Chen, product manager for elemental spectroscopy at Shimadzu Scientific Instruments.
In particular, heavy elements—such as arsenic, cadmium, lead, and mercury—are toxic to humans. “Those elements need to be monitored and controlled to ensure human health,” says Chen.
Infants face some of the most extreme dangers from heavy metals. “Infants and young children are especially vulnerable to these toxic effects due to their immature development and high ‘food intake/body weight’ ratio,”1 wrote Emily Bair, then a pediatric dietitian at Michigan Medicine and now an independent consultant. For example, just 50 micrograms of lead per liter of blood is toxic in young children. As a result, the U.S. Food and Drug Administration launched its Closer to Zero program to reduce contaminants, including heavy metals, in the diets of babies and young children.
Given the grave health concerns surrounding low levels of heavy metals, scientists need sensitive tools to track these substances, and that’s one job of elemental analyzers.
Tracking the toxicity
Elemental analyzers provide versatility in testing. “The primary benefit is the ability to quantify elements present in various matrices,” says Chen. “This plays a crucial role in ensuring compliance with regulations.”
To measure heavy metals in samples, scientists can select from various approaches. Some of the most commonly used technologies include atomic absorption spectroscopy, inductively coupled plasma optical emission spectroscopy, inductively coupled plasma mass spectrometry, and energy dispersive X-ray fluorescence (EDXRF) spectroscopy.
“Each technique has its pros and cons,” says Chen. “The right instrument will depend on several factors, including required sample throughput, budget, number of target analytes, and operator experience.”
Although regulatory compliance provides a key reason to use elemental analyzers, it also creates a challenge. “The increasingly strict regulations for compliance require elemental analyzers that can measure extremely low levels of heavy elements at a relatively high speed and with easy sample preparation,” she says. “This has driven the development of elemental analyzers.”
Technologies moving ahead
When thinking of examples of such technological development, Chen mentions modern EDXRF spectrometers: “Trends are for development and optimization of high-resolution detectors that can be operated at room temperature.”
Other trends in elemental analyzers reflect the ongoing direction of advances in other analytical technologies. These include “the need for instruments that are smaller, yet still offer the same functionality as larger instruments, and are easy to operate with user-friendly software,” she says.
Almost any advance in elemental analysis can be used to improve health around the world. As more devices become portable and easier to use, even more benefits will accrue.
1. “A Narrative Review of Toxic Heavy Metal Content of Infant and Toddler Foods and Evaluation of United States Policy.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9271943/.