How Scientists Keep Babies Safe
A scientific detective story unfolding in laboratories worldwide
Infant formula provides essential nutrition for millions of babies who aren't exclusively breastfed, serving as their sole source of nourishment during critical development periods. Yet few parents realize that this vital product could inadvertently contain potentially harmful chemicals formed during manufacturing. This is the story of how food chemists are using sophisticated technology to detect and monitor these contaminants, ensuring the safety of our most vulnerable population.
The story begins with refined vegetable oils—particularly palm oil—which are added to infant formula to provide essential fats necessary for infant growth and development. When these oils undergo high-temperature processing to remove unwanted tastes, colors, and odors, they can form unexpected chemical compounds called fatty acid esters of 3-monochloropropanediol (3-MCPD) and 2-monochloropropanediol (2-MCPD)5 .
During digestion, these esters break down into their "free" forms—3-MCPD, 2-MCPD, and glycidol—which have raised concerns in toxicological studies5 . Research in rodents has shown that 3-MCPD can cause adverse effects on kidneys and male reproductive organs, while both 3-MCPD and glycidol have demonstrated cancer-causing potential in animal studies5 .
What makes this issue particularly pressing is that infants are considered a vulnerable population—not only because of their developing bodies and organ systems but also because formula may be their exclusive food source for months5 . This means any contaminants in formula become their constant nutritional companions during a period of rapid growth and development.
3-MCPD (3-monochloropropane-1,2-diol)
2-MCPD (2-monochloropropane-1,3-diol)
Glycidol (2,3-epoxy-1-propanol)
How do scientists find these minute chemical needles in the haystack of complex infant formula? The answer lies in a sophisticated analytical technique called gas chromatography-tandem mass spectrometry (GC-MS/MS).
Gas chromatography (GC) works by separating the various components in a sample mixture. The sample is vaporized and carried by an inert gas through a specially coated capillary column. Different compounds travel through this column at different speeds based on their boiling points and chemical properties, emerging at characteristic "retention times"2 4 .
As compounds exit the GC column, they enter the mass spectrometer (MS), which bombards them with electrons, causing them to break into charged fragments. This process, called electron ionization, creates a distinctive fragmentation pattern that serves as a chemical "fingerprint" for each compound4 6 .
In traditional GC-MS, this is where the analysis would end. But GC-MS/MS adds another layer of precision. The first quadrupole (Q1) selects specific precursor ions, which are then fragmented in a collision cell (Q2), and the resulting product ions are analyzed in a third quadrupole (Q3). This two-stage mass filtration provides exceptional selectivity and sensitivity, enabling scientists to detect trace-level contaminants even in complex matrices like infant formula6 .
A groundbreaking 2015 study published in Food Additives & Contaminants exemplifies how scientists apply this technology to monitor infant formula safety1 . The research team faced a significant challenge: developing a method sensitive enough to detect these esters at potentially harmful levels in the complex matrix of infant formula.
The researchers used accelerated solvent extraction (ASE) to isolate the fat fraction containing the MCPD and glycidyl esters from the infant formula matrix. This technique uses high temperature and pressure to efficiently extract target compounds1 .
The extracted fats underwent a series of chemical reactions. Glycidyl esters were first converted to 3-monobromopropanediol (3-MBPD) esters. Then, both MCPD and 3-MBPD esters were hydrolyzed to release their free forms—3-MCPD, 2-MCPD, and 3-MBPD (from glycidyl esters)1 8 .
The free forms were chemically derivatized using phenylboronic acid, making them more volatile and suitable for GC-MS/MS analysis8 .
The derivatized samples were injected into the GC-MS/MS. The gas chromatograph separated the compounds, which were then ionized and fragmented in the mass spectrometer. The instrument operated in selected reaction monitoring (SRM) mode, monitoring specific fragment ions for each compound with high sensitivity6 .
The study analyzed 70 samples across seven different infant formula products, with dramatic results1 :
| Contaminant | Detection Frequency |
|---|---|
| 3-MCPD esters | Detected in all samples |
| Glycidyl esters | Detected in all samples |
| 2-MCPD esters | First systematic investigation |
Concentrations of 2-MCPD esters were approximately 50% of 3-MCPD ester levels.
Perhaps most importantly, the research revealed that concentration levels for both 3-MCPD and glycidyl esters were lower than those found in earlier investigations, suggesting that manufacturing improvements might already be making a difference1 .
In response to findings like these, regulatory agencies have sprung into action. The U.S. Food and Drug Administration (FDA) conducted extensive surveys of infant formula between 2013-2016, finding that average exposures to 3-MCPD esters for infants (0-6 months) ranged between 7-10 µg/kg body weight/day—exceeding the provisional maximum tolerable daily intake of 4 µg/kg body weight/day established by the Joint FAO/WHO Expert Committee on Food Additives5 .
The FDA engaged with infant formula manufacturers to share concerns and mitigation strategies. Subsequent testing revealed remarkable progress:
98 samples analyzed showed 3-MCPDE exposures exceeded JECFA recommended levels.
222 samples analyzed revealed three major manufacturers successfully reduced contaminant levels.
206 samples analyzed confirmed all four major manufacturers achieved reduced levels consistent with international norms.
This success story demonstrates how scientific monitoring coupled with industry engagement can drive meaningful improvements in food safety5 .
What does it take to run these sophisticated analyses? Here are some of the essential tools that food chemists use:
The core instrument that separates and detects the contaminants with exceptional sensitivity and selectivity6 .
Uses high temperature and pressure to efficiently extract fat from infant formula samples1 .
A derivatization reagent that reacts with the free forms of MCPDs to make them more volatile for GC analysis8 .
Chemically identical to target compounds but labeled with stable heavy isotopes for precise quantification8 .
The story of MCPD and glycidyl ester monitoring in infant formula represents a triumph of analytical chemistry serving public health. Through the sophisticated application of GC-MS/MS technology, regular monitoring, and collaboration between regulators and industry, significant progress has been made in reducing these contaminants in infant formula.
While the 2015 study marked an important step forward, the work continues. Scientists are still refining methods, establishing new regulations, and developing even better mitigation strategies—all in service of ensuring that infant formula remains as safe as possible for its most important consumers.
As research continues and methods improve, this scientific detective story will continue unfolding in laboratories around the world, providing parents with greater confidence in the products that nourish their babies during this critical period of life.