Earlier this month, the Journal of Psychopharmacology published the study “Who is ‘Molly’? MDMA Adulterants by Product Name and the Impact of Harm-Reduction Services At Raves,” about MDMA purity and whether laced samples are less likely to be consumed. Researchers found that only 60 percent of the 529 samples collected contained any amount of MDMA in them. Seasoned drug users already know that purity is a crapshoot, but this is hard evidence that what’s being sold as MDMA simply is not—for the most part.

The study measured samples of drugs sold as molly or ecstasy at events throughout the country over a five-year period. It’s the first of its kind in the United States, and the findings are major: not only is MDMA often adulterated, but researchers from Johns Hopkins School of Medicine and Denver-based Healthy Nightlife found that on-site pill-testing has a deterrent effect. In other words, if a user finds their supposed-MDMA has been adulterated, they’re far less likely to use it and endanger themselves with the unknown contents of their pills or powders.

The study also dealt with the alleged differences between molly and ecstasy. Assumptions often float around rave and festival scenes, especially among less-experienced users, that molly is more pure than ecstasy. After all, molly refers to powder form while ecstasy is the street name for pressed pills. The name molly is rumored to have originated from “molecular,” so amateur users make the faulty connection that the powder is somehow more authentic than its pressed-pill counterpart. Of course, a scientific-sounding name does not indicate anything of the sort: researchers determined that samples sold as molly and ecstasy have similar rates of adulteration.

In the 40 percent of samples that were cut with another drug, the usual suspects were at play: methylone, cathinones (common in bath salts) and methamphetamine all turned up fairly often. These combinations aren’t all deadly––admittedly, some can be quite fun––but other studies, conducted on both rats and humans, have shown that the mixing of substances like MDMA and meth has great potential to increase the negative effects of both. When users are combining substances intentionally to create a better roll, that’s one thing. But the fact that they’re unaware of what their drug contains in the first place is another.

About 32 percent of samples contained only nominal amounts of MDMA, if any. Of those users, a low number––26 percent––expressed intent to use their drugs after finding out what was really in them.

Even when samples genuinely contained MDMA, only about half of the people getting their drugs tested reported that they intended to use their drugs. Although this strange response could have been the result of misunderstanding or human error, it’s more probable that an impediment to getting accurate results may be that drug users are reluctant to give truthful information, out of fear of consequences. With almost all drug use having been shrouded in secrecy for decades, it’s no wonder people are hesitant to hand over their drugs and allow scientists to test them. Harm reduction efforts are partially impeded by the long legacy of criminalization––but hopefully, pill-testing can become more routine in rave and festival environments to save lives.

Similar studies on purity in other countries have yielded comparably alarming results. A Brazilian study conducted in 2015 found only about 44 percent of samples seized by police were actually MDMA. Other studies, like one in the Netherlands, have examined MDMA content over time. The Dutch researchers looked at fluctuations in purity over a 15-year period. Such a large study hasn’t been done before in the United States, and it confirms what a lot of drug policy experts have been saying for a long time: drugs are often cut, and they’re most dangerous when they’re cut––especially when users don’t know what else is in them.

Hopefully, these new results will serve as a wake-up call to legislators that more information on drug purity can prevent overdoses and toxic drug mixing, and even deter use if testing is provided on-site.

The more likely outcome, however, is that Attorney General Jeff Sessions and the rest of the Department of Justice will stubbornly refuse to scale back the drug war despite mounting evidence that a pragmatic approach makes the most sense. Given that they’re thinking about re-instating the hilariously flawed D.A.R.E. program, where police officers in uniform would lecture kids on the danger of drugs, it seems unlikely they’ll choose to champion harm reduction techniques.

Until better drug policy is pursued, MDMA will keep being cut with other substances all the damn time, and consumed by people who have no idea what’s in their little neon Tesla pills or capsules of powder. Creating environments where pills can be tested will help us actually know something about what we’re putting into our bodies––and that’s the obvious first step. With more peace of mind, rolling will not only be safer, but also more fun.

Liz Wolfe is managing editor of Young Voices. She lives in Austin, Texas, where she writes about criminal justice and libertarianism. Follow her on Twitter: @lizzywol.