Maine cannabis regulators have issued a new medical marijuana patient advisory after laboratory testing found unsafe levels of mold, yeast and several types of bacteria in flower and pre-rolls produced and sold by The B Maine, formerly known as Dr. Melo’s, in Lebanon. The October 14 warning covers six cannabis strains and follows a state investigation that began after regulators received a complaint about conditions at the company’s cultivation facility in mid-September.
The Maine Office of Cannabis Policy, initially tested Florida Oranges flower grown at the facility and detected microbial contamination exceeding the standards used for the state’s regulated adult-use cannabis market. Investigators then tested additional products and discovered similar problems in another flower strain and four pre-roll varieties. The findings have renewed scrutiny of one of Maine’s most controversial cannabis policies: unlike recreational marijuana sold through the adult-use system, medical cannabis is not required to undergo mandatory contaminant testing before reaching patients.
Important Patient Alert: Six Affected Cannabis Products
Patients should immediately check whether they possess any of the following medical cannabis products produced and sold by The B Maine, formerly Dr. Melo’s, in Lebanon, Maine:
Affected Flower
- Florida Oranges
- Skunk Hero
Affected 1-Gram Pre-Rolls
- Bad Apple
- Cherry AK
- Head Candy
- Tropsicles
No affected batch numbers were published by Maine regulators. Unlike Maine’s adult-use cannabis system, the Medical Use of Cannabis Program does not require the same mandatory inventory tracking and batch identification system. As a result, the Office of Cannabis Policy said it cannot provide the level of batch-specific information normally included in an adult-use marijuana recall.
Patients should therefore not assume a product is safe simply because its packaging does not contain a batch number matching a recall notice. Anyone possessing Florida Oranges, Skunk Hero, Bad Apple, Cherry AK, Head Candy or Tropsicles produced and sold by The B Maine should stop using the affected product. The B Maine voluntarily surrendered contaminated products to state regulators for destruction. Patients who consumed the products and develop symptoms or adverse reactions should contact a healthcare provider, while a medical emergency warrants calling 911.
Some Contamination Levels Were Far Above Adult-Use Limits
Laboratory results released by state regulators show that several samples did not merely exceed adult-use cannabis thresholds by a small margin. One Florida Oranges flower sample contained more than 30,000 colony-forming units per gram of coliform bacteria when the adult-use limit is 1,000. Enterobacteriaceae were also measured above 30,000 CFU per gram against the same 1,000-CFU threshold, while yeast and mold exceeded 30,000 CFU per gram compared with an adult-use maximum of 10,000.
A second Florida Oranges sample produced even more striking results. Aerobic bacteria and Enterobacteriaceae both exceeded 490,000 CFU per gram, and yeast and mold were reported as too numerous to count. Skunk Hero flower likewise contained more than 490,000 CFU per gram of aerobic bacteria and Enterobacteriaceae, along with 31,000 CFU per gram of yeast and mold. These levels would have caused the products to fail the microbiological testing required in Maine’s adult-use cannabis market.
Several Pre-Rolls Also Showed Heavy Microbial Growth
The four affected pre-roll strains showed varying contamination patterns. Bad Apple contained 5,700 CFU per gram of Enterobacteriaceae and 24,000 CFU per gram of yeast and mold, both exceeding adult-use thresholds. Cherry AK contained more than 490,000 CFU per gram of aerobic bacteria and Enterobacteriaceae, while yeast and mold were reported as too numerous to count.
Head Candy contained more than 490,000 CFU per gram of both aerobic bacteria and Enterobacteriaceae, 20,000 CFU per gram of coliforms and 34,000 CFU per gram of yeast and mold. Tropsicles showed similarly elevated results, including more than 490,000 CFU per gram of aerobic bacteria and Enterobacteriaceae and 44,000 CFU per gram of yeast and mold. The widespread failures across several products indicate that regulators were dealing with more than a single isolated contaminated package.
Why Mold in Cannabis Can Be a Medical Concern
Cannabis flower is an agricultural product and naturally comes into contact with microorganisms during cultivation, drying, curing, trimming, storage and packaging. Warm temperatures and high humidity can create ideal conditions for mold and yeast to multiply, particularly inside dense cannabis flowers where moisture can remain trapped. Common fungal genera associated with cannabis include Aspergillus, Penicillium and Fusarium, some of which include species capable of producing toxins or causing opportunistic infections.
Research has documented these concerns for decades. A 1983 study published in the Journal of Allergy and Clinical Immunology examined marijuana samples and found fungi in 13 of 14 specimens, including Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger and Penicillium species. Researchers also demonstrated that Aspergillus fumigatus could pass through a burning marijuana cigarette, showing that smoking contaminated cannabis does not necessarily eliminate exposure to viable fungal material.
Immunocompromised Patients Face the Greatest Potential Risk
The clinical danger of contaminated cannabis is not equal for everyone. A healthy adult may inhale fungal material without developing a serious infection, while a person whose immune system is suppressed by cancer treatment, organ transplantation, immune-modifying medications or another medical condition can be substantially more vulnerable to invasive fungal disease. This is especially important in a medical cannabis program because some patients use marijuana while undergoing treatment for serious illnesses.
A well-known case report in the journal Chest described a bone marrow transplant recipient who developed fatal pulmonary aspergillosis after smoking marijuana. Investigators cultured Aspergillus fumigatus from the patient’s cannabis and identified the same organism in lung tissue. Other medical reports have described pulmonary fungal infections associated with cannabis exposure, including mucormycosis and chronic pulmonary aspergillosis. Individual cases cannot determine how frequently contaminated marijuana causes infection, but they establish that serious illness is biologically possible.
Larger Studies Also Suggest an Association With Fungal Infection
Population-level research has found a similar signal. A study published in Emerging Infectious Diseases examined commercially insured Americans and compared fungal infection diagnoses between people with documented cannabis use and those without it. Fungal infections remained uncommon overall, but people identified as cannabis users had higher odds of receiving a fungal infection diagnosis even after researchers accounted for factors including age and immune-compromising conditions.
The study could not prove that cannabis caused individual infections, nor could researchers determine whether marijuana exposure was the source of a specific organism. Cannabis users can differ from nonusers in numerous ways that affect health. Still, when those findings are considered alongside laboratory evidence showing fungal contamination of cannabis and clinical reports linking marijuana with opportunistic infections, they reinforce the need for particular caution among medically vulnerable patients.
Bacteria Can Signal Problems With Cultivation and Handling
Maine regulators also detected aerobic bacteria, coliforms and Enterobacteriaceae in the affected products. These measurements do not mean every organism in the cannabis was necessarily a dangerous human pathogen. Total aerobic bacterial counts broadly measure microbial load, while coliform and Enterobacteriaceae testing can act as indicators of poor sanitation or contamination during cultivation, processing and handling.
Extremely high counts remain concerning because they indicate that conditions allowed substantial microbial growth. Excess moisture, contaminated water, soil, equipment, worker handling, poor drying practices or inadequate storage can all contribute. Adult-use microbiological thresholds are designed to prevent cannabis with excessive microbial loads from reaching consumers even when laboratories have not identified the exact bacterial species responsible.
Maine Medical Marijuana Is Not Required to Pass Contaminant Testing
The most significant policy issue exposed by the advisory is that the affected products could legally be sold without first passing contaminant testing. Maine’s medical cannabis program does not require every batch of marijuana to be screened for mold, microbes, pesticides, heavy metals or other hazards before sale. Some caregivers and dispensaries voluntarily conduct laboratory testing, but testing is not universally mandatory.
Maine regulators specifically said none of the affected products sold by The B Maine were required to undergo contaminant testing before sale, and none had been tested. The problem came to regulators’ attention after a complaint about conditions at the Lebanon cultivation facility prompted an investigation and state-directed testing.
The adult-use market operates under a substantially different system. Recreational cannabis must satisfy mandatory testing standards before it can legally be sold, including standards for microbiological contaminants. Adult-use packages also include batch identifiers and are subject to formal recall procedures. Those differences explain why Maine can publish highly specific batch numbers for recreational recalls but could not do so for the latest medical cannabis patient advisory.
Maine Regulators Cannot Issue the Same Recall Used for Adult-Use Cannabis
Another major distinction involves enforcement authority. The Office of Cannabis Policy can order recalls within Maine’s Adult Use Cannabis Program when testing or investigations uncover unsafe products. State law does not grant the agency the same recall authority within the Medical Use of Cannabis Program.
That limitation means regulators issued a patient advisory rather than a conventional mandatory recall. The B Maine voluntarily agreed to surrender the contaminated products to OCP for destruction, but the state’s ability to track every potentially affected medical package is more limited because the program lacks the mandatory inventory-tracking structure used for recreational cannabis.
The absence of batch information therefore does not mean regulators found only one unidentified batch. It reflects a structural difference in Maine’s medical cannabis regulatory system. Patients must rely primarily on the product strain, producer and source information provided in the advisory.
Maine Previously Found Contaminants in 42 Percent of Medical Samples
The concern is not new. In 2023, the Office of Cannabis Policy conducted one of the most significant examinations of Maine’s medical cannabis supply by collecting and testing 120 samples. Fifty samples—approximately 42 percent—contained at least one contaminant that would have caused the cannabis to fail under the safety standards applied to recreational marijuana.
The audit recorded 30 failures involving yeast and mold, 26 involving pesticides, four involving heavy metals and one involving filth or foreign material. Some products failed in multiple categories. The findings became a central part of the debate over whether Maine should require medical cannabis testing, particularly because patients purchasing marijuana through a state-recognized medical program may reasonably expect that products have been screened for basic health hazards.
Recent Research Continues to Find Microbes on Cannabis
Scientific interest in cannabis contamination has expanded with legalization. Researchers examining marijuana flower have identified fungi capable of producing mycotoxins, including species within the Aspergillus, Penicillium and Fusarium genera. Studies evaluating cannabis decontamination have found that treatments such as gamma irradiation can dramatically reduce microbial populations, although no remediation method necessarily eliminates every possible organism or contaminant.
Recent reviews of medical cannabis sanitation have discussed approaches including irradiation, electron-beam treatment, ozone and newer non-thermal systems. Producers face the challenge of reducing microbial contamination without excessively altering cannabinoids, terpenes, appearance or other characteristics of the plant. Whatever method is chosen, independent laboratory testing remains the most direct method of confirming that a finished batch meets established microbial safety standards.
Maine Has Issued Multiple Cannabis Contamination Warnings
The B Maine advisory follows several other cannabis safety actions within the state. Earlier in 2026, Maine issued medical patient advisories involving pesticide-contaminated cannabis concentrates, contaminated flower and excessive butane in cannabis products. The adult-use market has also experienced recalls involving mold, yeast and other microbial contaminants.
In June, regulators recalled Drip Burger flower produced by Green Trap after audit testing identified unsafe levels of yeast and mold. Other adult-use recalls have involved products that entered retail stores before later state audit testing revealed contamination. These incidents demonstrate that mandatory testing cannot prevent every problem, but it gives regulators additional tools for tracing products by batch and removing affected inventory when safety issues emerge.
Medical Cannabis Creates a Unique Safety Responsibility
Microbial contamination carries particular significance when marijuana is being used therapeutically. Some medical patients have cancer, chronic inflammatory disease, organ transplants or other conditions that compromise immune defenses. Others may take corticosteroids, chemotherapy medications or biological therapies that increase susceptibility to infection. For these patients, the microbial quality of inhaled cannabis can matter considerably more than it does for many healthy recreational users.
Medical literature examining cannabis use among immunocompromised patients has repeatedly warned that plant material can harbor microorganisms capable of producing opportunistic respiratory infections. Researchers have encouraged physicians to consider marijuana exposure when evaluating unexplained fungal infections and to discuss potential contamination risks with vulnerable patients who use inhaled medical cannabis.
What Maine Patients Can Do to Reduce Their Risk
Patients who possess Florida Oranges, Skunk Hero, Bad Apple, Cherry AK, Head Candy or Tropsicles from The B Maine should stop using those products. Visible mold is not required for cannabis to be contaminated, and flower that appears or smells normal can still contain microbial levels far above accepted health standards. Removing a visibly moldy portion also does not guarantee that fungal spores or bacteria have not spread throughout the product.
Patients purchasing medical cannabis in Maine can ask whether a product has undergone independent laboratory testing and request a Certificate of Analysis. The certificate should correspond to the exact product or production lot being purchased and should indicate which tests were actually performed. A potency test showing THC and CBD content does not demonstrate that a sample passed tests for mold, microbes, pesticides or heavy metals.
Immunocompromised patients and people with chronic respiratory diseases may have additional reasons to avoid untested inhaled cannabis. Anyone in a medically vulnerable group should consider discussing cannabis use and route of administration with a healthcare professional familiar with their condition.
The Advisory Reopens Maine’s Medical Cannabis Testing Debate
The October warning places Maine’s two cannabis systems in sharp contrast. Products producing the microbial results found during The B Maine investigation would have failed the state’s adult-use testing standards. In the medical system, however, routine contaminant testing was not mandatory, and the products were sold before a complaint triggered regulatory testing.
Supporters of Maine’s existing medical model have historically argued that mandatory testing and other recreational-style regulations could impose substantial costs on small caregivers and reduce patient access. Patient-safety advocates counter that cannabis sold for medical use should not receive weaker contaminant oversight than recreational marijuana, particularly when many medical patients may be especially vulnerable to infection.
The absence of batch numbers in this advisory may add another dimension to that debate. Mandatory tracking does more than help regulators monitor inventory—it allows patients to identify precisely which package or production lot is involved when contamination is discovered.
A Warning With Implications Beyond One Cannabis Business
The immediate warning concerns six products produced and sold by The B Maine: Florida Oranges and Skunk Hero flower, along with Bad Apple, Cherry AK, Head Candy and Tropsicles pre-rolls. Laboratory testing found bacteria, yeast and mold at levels that in several samples exceeded adult-use safety limits by enormous margins, including multiple results above the laboratory’s upper measurable range.
For patients, the safest course is straightforward: affected products should no longer be consumed, even though Maine regulators could not publish batch-specific identifiers. Symptoms following exposure should be taken seriously, particularly among people with weakened immune systems or respiratory disease.
For Maine policymakers, the findings create a broader question about the future of medical cannabis oversight. The state operates a medical marijuana market where contaminant testing and batch tracking remain less rigorous than in the recreational system, despite previous state sampling finding that approximately four in ten medical cannabis products tested would have failed adult-use safety standards. The latest contamination warning ensures that mandatory testing, product tracking and patient protection will remain central issues in Maine’s cannabis policy debate.
