Pesticides can help farmers increase food production, reduce high losses to crops, and even prevent the spread of insect-borne diseases, but since these chemicals may also eventually enter human food, ensuring its safety is essential. For a commonly used pesticide called glyphosate, people are worried about how safe the food is and how safe one of its by-products is called AMPA. Researchers at the National Institute of Standards and Technology (NIST) are developing reference materials to advance the accurate measurement of glyphosate and AMPA, which are often found in oat foods.
The Environmental Protection Agency (EPA) sets tolerances for pesticide levels in foods that are still considered safe to eat. Food manufacturers test their products to ensure they comply with EPA regulations. However, in order to ensure the accuracy of the measurement results, they need to use a reference substance (RM) with a known glyphosate content to compare with their products.
In oatmeal or oatmeal-based products that use a lot of pesticides, there is no reference material that can be used to measure glyphosate (the active ingredient in the commercial product Roundup). However, a small amount of food-based RM can be used to measure other pesticides. To develop a glyphosate and meet the immediate needs of manufacturers, NIST researchers optimized a test method to analyze glyphosate in 13 commercially available oat-based food samples to identify candidate reference substances. They detected glyphosate in all samples, and AMPA (short for amino methyl phosphonic acid) was found in three of them.
For decades, glyphosate has been one of the most important pesticides in the United States and the world. According to a 2016 study, in 2014 alone, 125,384 metric tons of glyphosate were used in the United States. It is a herbicide, an insecticide, used to destroy weeds or harmful plants that are harmful to crops.
Sometimes, the amount of pesticide residues in food is very small. As far as glyphosate is concerned, it can also be broken down into AMPA, and it can also be left on fruits, vegetables and grains. The potential impact of AMPA on human health is not well understood and is still an active area of ​​research. Glyphosate is also widely used in other grains and grains, such as barley and wheat, but oats are a special case.
NIST researcher Jacolin Murray said: “Oats are as unique as grains.” “We chose oats as the first material because food producers use glyphosate as a desiccant to dry crops before harvesting. Oats often contain a lot of glyphosate. Phosphine.” Dry crops can make harvesting earlier and improve crop uniformity. According to co-author Justine Cruz (Justine Cruz), due to the wide range of uses of glyphosate, glyphosate is usually found to be higher in levels than other pesticides.
The 13 oatmeal samples in the study included oatmeal, small to highly processed oatmeal breakfast cereals, and oat flour from conventional and organic farming methods.
The researchers used an improved method of extracting glyphosate from solid foods, combined with standard techniques called liquid chromatography and mass spectrometry, to analyze the glyphosate and AMPA in the samples. In the first method, a solid sample is dissolved in a liquid mixture and then glyphosate is removed from the food. Next, in liquid chromatography, the glyphosate and AMPA in the extract sample are separated from the other components in the sample. Finally, the mass spectrometer measures the mass-to-charge ratio of the ions to identify different compounds in the sample.
Their results showed that the organic breakfast cereal samples (26 ng per gram) and organic oat flour samples (11 ng per gram) had the lowest levels of glyphosate. The highest level of glyphosate (1,100 ng per gram) was detected in a conventional instant oatmeal sample. The AMPA content in organic and conventional oatmeal and oat-based samples are far lower than the glyphosate content.
The contents of all glyphosate and AMPA in oatmeal and oat-based grains are far below the EPA tolerance of 30 μg/g. Murray said: “The highest glyphosate level we measured was 30 times lower than the regulatory limit.”
Based on the results of this study and preliminary discussions with stakeholders interested in using RM for oatmeal and oat grains, the researchers found that developing low levels of RM (50 ng per gram) and high levels of RM may be beneficial. One (500 nanograms per gram). These RMs are beneficial to agricultural and food testing laboratories and food manufacturers, who need to test the pesticide residues in their raw materials and need an accurate standard to compare with them.