A few months ago, I got a package in the mail from a new CBD brand called Populum. When I opened the box, I was surprised to see that a product wasn’t the only thing inside—there was also a mega-lengthy list of lab results for the bottle of hemp oil I held in my hands. It looked exactly like the printout you get when you have bloodwork done at the doctor, except instead of, say, vitamin D and hormone levels, this one was testing for heavy metals, industrial chemicals, microbes and mold toxins, and even the levels of CBD and other cannabinoids in the product.

Until that point, I’d never actually thought about what was in the CBD products I’d been test-driving on a near daily basis. But as someone with an irrational fear of conventionally-grown kale, I was shook—are contaminants really that big of a problem on the CBD market?

According to Anna Symonds, director of education at Oregon cannabis farm East Fork Cultivars, there actually are several toxins that can potentially make their way into CBD products, starting on the farm. “All cannabis plants, including hemp, are bioaccumulators,” says Symonds, who runs East Fork Cultivars’ CBD Certified program. “That means they will pull any existing contaminants out of the soil and into the plant—things like heavy metals and pesticide and petrochemical residues. And if the grower is using pesticides, those can also remain in the plant.”

To be clear, the produce we eat can also contain heavy metals and chemical traces, and we’re exposed to plenty of toxins in the environment, too. But if you’re someone who prioritizes organic food from farms with good soil quality, it’s worth thinking about hemp in the same way you’d think about shopping for strawberries and spinach.

The manufacturing process, too, can involve some sketchy substances—and since the CBD industry is basically unregulated right now, some of these can slip through into the finished product. “Depending on the [method used to extract CBD from the hemp], traces of solvents can be left behind,” says Symonds. “These can include things like ethanol, also known as grain alcohol, or hydrocarbons like butane, propane, and hexane.”

Oh, and let’s not forget about of the things that manufacturers may add to the finished product, including artificial colorings and flavorings, preservatives, terpenes from non-cannabis sources, and thinning agents in vape cartridges that may turn into harmful compounds when heated, like propylene glycol (PG or PPG), polyethylene glycol (PEG) 400, vegetable glycerin, or even medium-chain triglycerides (MCT). “Product makers are not always required to disclose all of these things on their labels,” says Symonds. And, as such, they can sneak in unnoticed.

That has to be it, right? Sorry, but no. There’s also the fact that the amount of CBD within a product is sometimes mislabeled. Back in 2017, researchers tested 84 CBD products from 31 different companies, and found that 70 percent of them contained either more or less CBD than indicated on the packaging.

This continues to be an issue today, says Anthony Saniger, founder of CBD retailer Standard Dose. He’s seen it firsthand, since Standard Dose conducts its own third-party, independent lab tests for pesticides, heavy metals, and potency on every product it carries. “The first thing I look at on the lab tests is the percentage of CBD on the bottle and what the milligrams are per one ounce,” he says. “If a bottle says it has 150 mg of CBD in it, does that 150 mg mean per one-ounce bottle? Or is it per dose? Because the FDA isn’t telling CBD brands that they have to label their products a certain way, they can essentially put whatever they want on the packaging, and that can be confusing for consumers.”

Yikes. So how do I make sure I’m getting the cleanest, most legit CBD product possible?

First of all, don’t freak out. Many next-gen CBD brands are totally aware of the contaminants and potency issues that could potentially affect their products, and are committed to creating transparency around this issue.

Symonds recommends starting by seeking out CBD products that are made using American-grown, USDA-certified organic hemp. Why hemp that’s born in the USA? “It is very common for imported products made from industrial hemp to be contaminated, because there are currently no testing requirements for those kinds of products,” she says. “Over half of the world’s industrial hemp is grown in China, where there is little to no environmental regulation or consumer protection.”

That being said, she admits that it’s not always easy to find products made with certified-organic hemp at this early stage of the industry’s development. (Remember, the Farm Bill, which effectively legalized CBD, just passed at the end of 2018.) So, in the absence of that, you can ask for independent testing results from any brand you’re considering. “The maker should include plenty of information about where and how the source material was grown, and they should provide test results from a third-party accredited lab for levels of CBD and lack of contaminants” says Symonds. She adds that you should also look at the product’s ingredient list to see if any questionable additives are included.

Drew Todd, co-founder of new CBD brand Feals, recommends you also seek out intel on how a brand extracts its cannabinoids from hemp. (This information should be on their website.) “When it comes to extraction, look for a clean CO2 extraction process versus the use of harmful solvents,” he says. Todd adds that solvents are more common in products that contain CBD isolate, which are more refined, whereas full-spectrum CBD products are more likely to contain heavy metals and pesticides.

Yes, this is a lot of research that none of us have time for, which is why a growing number of brands, like Populum and Feals, are including certificates of analysis alongside the product when it’s shipped. Others are putting QR codes on the back of their packaging that lead you directly to their testing results, says Saniger. Look for three specific things when reading lab data, says Populum founder Gunhee Park. “First, check the cannabinoid profile: Does it show the correct amount of CBD per serving as the brand is claiming? Also, make sure there are no toxins or solvents, and the date of the lab test is fairly recent.”

Or you could buy your CBD from a retailer like Standard Dose, which does the work for you. “This is what we should be doing as retailers—ensuring the quality of the products that we’re selling—because there is no FDA regulation,” says Saniger. “I’m excited that big players want to jump into the space, but I’m seeing that some of them aren’t vetting their products at all. They’re looking at branding, packaging, and how the product feels, but I feel like we take that one step further.”

Ultimately, he says, CBD brands in general are becoming more open about what’s in their products, which should help separate the shady players from the ones who are doing it right. “Even since we first announced we were doing lab testing, I’ve already noticed a lot more brands not questioning why we’re doing that anymore. At the beginning, they’d kind of look at me like I was strange, but now they’re feeling more comfortable with it.”

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