Because the overuse of antibiotics can increase resistance to antibiotics and make them less effective for both humans and animals, the U.S. Food and Drug Administration has set limits on detectable levels of antibiotics in food.
Residues of at least one antibiotic were found in 60% of the conventional or non-organic milk samples collected from retail stores across the United States, while none were detected in any of the organic samples, according to a study published in Public Health Nutrition 2019.
Residues of several currently used pesticides were also detected in conventional (26-60%) but in none of the organic milk samples.
Bovine growth hormone residue levels were found to be 20 times higher in conventional than organic milk samples.
Pesticide and antibiotic levels were within federally allowed limits with a few important exceptions.
In this study, among the conventional samples, antibiotic residue levels exceeded federal limits for amoxicillin in one of the samples (3%), as well as sulfamethazine (37%) and sulfathiazole (26%) in multiple samples.
The authors of the study said more research is needed to understand the long-term health impact, if any, of exposure to these chemicals used by some milk producers.
Choosing to consume milk produced organically would minimize exposure and any possible risks. According to U.S. Department of Agriculture standards, dairy animals must be managed organically for at least 12 months for milk or dairy products to be sold, labeled or represented as organic.
In 2018, organic sales in the United States passed the $50 billion mark and hit a record $52 billion, up 6.3% from the previous year, according to a survey conducted for the Organic Trade Association.
Organic dairy is still the No. 2-selling category in the U.S. organic sector, even though growth slowed for the second straight year due largely to shifting diet trends. Shoppers, especially young families, increasingly are seeking products made from high-quality, simple ingredients from brands committed to sustainable agriculture and its environmental benefits. They turn to organic dairy as being free of antibiotics, synthetic hormones and chemicals.
“Organic is now considered mainstream, but the attitudes surrounding organic are anything but status quo,” said Laura Batcha, chief executive officer and executive director of OTA.
Consumers seeking organic milk should look for the “USDA Organic” seal in the supermarket.
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