Beta-myrcene is generally safe at the small amounts found in foods, beverages, and flavoring products. It holds GRAS (Generally Recognized as Safe) status from the FDA as a flavoring agent, and the European Food Safety Authority has concluded it raises no safety concerns at estimated dietary intake levels. The picture gets more complicated, though, when you look at high-dose animal studies, which found tumor growth in rats and mice given large quantities over two years.
Where You Already Encounter It
Beta-myrcene is one of the most common terpenes in nature. It’s the compound behind the earthy, slightly fruity aroma in hops, mangoes, lemongrass, bay leaves, and cannabis. Hops contain the highest concentrations of any well-studied source, reaching up to 10 grams per kilogram of dry weight. If you drink beer, eat mangoes, or cook with bay leaves, you’re already consuming small amounts of myrcene regularly.
In the food industry, it’s used as a flavoring agent and assigned FEMA number 2762, a designation confirming its safety for that purpose. The amounts used in flavoring are tiny fractions of a gram, far below levels that raise concern in toxicology studies.
What Rodent Studies Found at High Doses
The most significant safety data comes from a two-year study by the National Toxicology Program, which gave rats and mice daily oral doses of beta-myrcene ranging from 0.25 to 1 gram per kilogram of body weight. For context, that’s an enormous dose. Scaled to a 70-kilogram person, the lowest dose tested would be roughly 17.5 grams per day, thousands of times more than anyone would get from food or flavoring.
In male rats, the study found “clear evidence of carcinogenic activity” based on increased kidney tumors, including both benign and malignant growths. Female rats showed weaker evidence, with only a slight increase in kidney tumors. Kidney damage short of cancer, including tissue degeneration and mineral buildup, was widespread across nearly all dosed groups of both sexes.
In mice, the pattern shifted to the liver. Male mice showed clear evidence of liver cancer, including hepatocellular carcinoma and a rare tumor type called hepatoblastoma. Female mice had a marginal increase in liver tumors, classified as equivocal evidence. Liver cell enlargement was also common at the higher doses.
These findings sound alarming, but they need context. Rodent gavage studies deliver concentrated doses directly into the stomach daily for two years. This method is designed to stress-test a substance and identify hazards, not to replicate real-world human exposure. Many compounds that are safe at normal dietary levels produce tumors in rodents at extreme doses. The NTP results triggered further review but did not lead regulators to pull myrcene from approved food use.
What Regulators Have Concluded
The FDA continues to list beta-myrcene as a permitted flavoring substance. The European Food Safety Authority reviewed toxicity data on myrcene as part of a broader flavoring group evaluation in 2015 and concluded that none of the substances in the group, myrcene included, showed genotoxic potential, meaning they don’t directly damage DNA. EFSA determined that all 29 substances in the evaluation “do not give rise to safety concerns at their levels of dietary intake.”
The key phrase is “at their levels of dietary intake.” Regulators draw a clear line between the trace amounts people consume through food and flavoring versus the massive doses used in animal toxicology experiments. Safety conclusions are tied to realistic exposure levels, not worst-case laboratory scenarios.
Acute Toxicity Is Very Low
Beta-myrcene has an oral LD50 (the dose that would be lethal to half of test animals) greater than 5,000 milligrams per kilogram in rats. The same threshold holds for skin exposure in rabbits. In toxicology, anything above 5,000 mg/kg is classified in the lowest toxicity category. For practical purposes, beta-myrcene is very difficult to poison yourself with in a single exposure.
Skin and Allergy Reactions
Skin sensitization from myrcene is rare. A clinical study across six European centers patch-tested 1,511 consecutive dermatology patients and found just one positive reaction, and that was to oxidized myrcene rather than fresh myrcene. Oxidation matters here: like many terpenes, myrcene can break down when exposed to air and light over time, and these degradation products are more likely to irritate skin than the original compound. If you use essential oils or products containing myrcene, storing them properly (sealed, away from heat and light) reduces even that small risk.
The Supplement and Cannabis Question
Most people searching about myrcene safety are encountering it through cannabis products or terpene supplements, not through mango slices. This matters because concentrated terpene products can deliver much higher amounts than food sources. A few drops of pure myrcene isolate contain far more than you’d get from an entire meal seasoned with bay leaves and lemongrass.
One small pilot study examined beta-myrcene’s effects on driving performance and divided attention in humans but did not collect data on subjective side effects like drowsiness, so the clinical evidence on how people actually feel after taking isolated myrcene remains thin. Myrcene is widely described as having sedative properties in cannabis culture, but controlled human data supporting that claim is limited.
If you’re using terpene-enriched products, the dose matters more than the substance itself. The safety profile that regulators have endorsed applies to flavoring-level exposures, not to concentrated supplementation. Without established human dosing guidelines for isolated myrcene supplements, there’s a gap between what’s known to be safe and what some products deliver.