Mycotoxins are a never-ending reality and threat to pet food safety, and each year brings a spate of pet food recalls related to mycotoxin contamination, especially from aflatoxin. That’s a chief reason that testing for the contaminants, starting with sampling and testing incoming raw materials, is so important.
The other reason? Because there is no way to mitigate mycotoxins once they’re in pet food products or even raw materials, according to experts Christy Swoboda, technical services director with Romer Labs, and Randy Ford, chief scientific officer with Red Collar Pet Foods.
Swoboda and Ford answered questions from pet food professionals about mycotoxins during an Ask the Pet Food Pro Zoom chat on December 16, 2021. The chat was sponsored by Romer Labs.
Mycotoxin mitigation is essentially a myth
Once mycotoxins are present in raw materials or end up in finished pet food products, they are there to stay, the experts stressed, even if they’re at safe levels. “Mitigation is about the upstream knowledge, because your testing doesn’t mitigate,” said Ford, referring to learning about the risk and prevalence of certain mycotoxins in your production area or where the ingredients are grown. “The only tool we have at the factory is testing, and that’s not mitigating. So, you have to do your homework, you have to get these predictive models, talk to your test kit suppliers because they’ll have a knowledge base and so on. The one mitigation for mycotoxins is, don’t buy contaminated grains.”
In terms of predictive models and mycotoxin reports, Swoboda offered several sources, though many are post harvest for corn and grain crops. “Several [test kit] manufacturers put out a kind of mycotoxin crop blast on predefined schedules as we move through crop harvest,” she said. “So we’ll get some information, either what we’re hearing from our customers or what we’re seeing internally, analytically. But for me, some of the best information about the crop comes out after the harvest is complete.”
She added that Romer and some of its competitors then look back at samples they’ve analyzed, perhaps up to 1,500, and do a deep dive into the data, including a state-by-state analysis, to create reports for their customers and others in the industry.
“FDA has a summary report that comes out every year after it as well, so there is information available, even if it’s not applicable in real time because it’s always post harvest,” Swoboda said. “At least it can be used as a guide to what’s expected. They’ve been doing a study since 2011. So at least you have a year-over-year starting point, a regionalized approach to start with, from the data.”
Storage conditions are also key
Swoboda and Ford explained that mycotoxins may be present at such low levels that they pose absolutely no safety risk—and, you can possibly eradicate and mitigate mold or any other fungi developing from the mycotoxins (though that can be a tough thing to do). But the mycotoxin organisms themselves remain.
That’s why storage conditions for both raw materials and finished pet food products are crucial. As long as they are stored properly, with no exposure and low moisture, the mycotoxins themselves won’t increase in number or present a threat if they were originally at very low levels, below thresholds that could cause harm to pets. “Definitely below 15% [moisture] for grain going into storage,” Swoboda explained in terms of safe storage levels. “In some cases, you need to go even further than that, below, say, 12%. So yes, making sure that it’s harvested when dry and then stored dry” is crucial, she added, and continued dry conditions are critical to slow the threat of mold developing from mycotoxins. “You know, it’s hard to stop it. But it will greatly slow it.”
References: Mycotoxin levels, sampling, testing protocols
Regarding safe levels of mycotoxins, of the six types most frequently affecting common pet food ingredients like grains and corn—aflatoxin, DON (vomitoxin), zealarone, fumonisin, ochratoxin and T2/HT2 (both are types of tricothecene)—only aflatoxin has a limit for pet food regulated by the Food and Drug Administration (FDA). That is 20 parts per billion.
“If you put something out there in commerce that’s over 20 parts per billion, then it’s against the law,” Ford stressed. “If you put something out there that’s at 50 or 100 parts per billion, your phone’s going to start ringing because you’re going to be harming pets.”
The 20 parts per billion is known as an FDA action limit, he explained; other mycotoxins may have advisory and guidance levels of severity as defined by FDA. He and Swoboda referred listeners to the Mycotoxin Handbook from the U.S. Department of Agriculture (USDA), which includes safe levels for mycotoxins, plus a complementary USDA handbook that includes information and guidance on proper sampling and testing techniques. “Everybody on this call should have both of these references in their library before they go one more day,” Ford stressed.
