carcinogenicity comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-08-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
Cardarine is explicitly prohibited by the World Anti-Doping Agency under the class of PPARδ agonists. Its presence in urine or blood samples can be detected using mass spectrometry-based methods, often liquid chromatography-tandem mass spectrometry. Athletes who test positive may face sanctions, including bans from competition. The compound is also regulated as a prescription-only or unapproved drug in many countries. Enforcement varies by jurisdiction, and some regions treat it as a controlled substance. Online sales may occur despite these restrictions, creating quality and legal risks.
| Property | Value | Notes |
|---|---|---|
| IUPAC name | {4-[({4-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-thiazol-5-yl}methyl)sulfanyl]phenoxy}acetic acid | Systematic name for GW501516 |
| CAS Registry Number | 317318-70-0 | Unique identifier for the parent compound |
| Molecular formula | C21H18F3NO3S2 | Includes carbon, hydrogen, fluorine, nitrogen, oxygen, and sulfur |
| Molecular weight | 453.5 g/mol | Approximate value for the neutral form |
| Appearance | White to off-white powder | Typical description for purified laboratory material |
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
The international nature of the high seas, means they have limited policing capabilities, which makes the oceans particularly vulnerable to the illicit drug trade. Excluding the 12 - 24 nautical miles surrounding each of the littoral states, the oceans are generally not owned by any particular country. Except for in their territorial waters, law enforcement ships can do very little in terms of policing unless a vessel is registered to their own country. These problems are heightened by a lack of international agreement and cooperation, resulting in an absence of sufficient legal infrastructure to handle the problem. This problem has been overcome previously, as laws have been implemented to enable the boarding of ships in relation to other maritime crimes, such as piracy, but this has not yet been effectively implemented in regards to drug trafficking. In practice, this has meant that vessels suspected of trafficking these illegal substances cannot be boarded by law enforcement, and thus face no legal consequences. Traffickers have taken advantage of this, and are increasingly capitalising on illicit trade through maritime routes. Of the 400 million containers shipped worldwide in 2009, only 2% of these were inspected.
== Professional activities == After earning a Ph.D. degree in biochemistry, a medical degree, and completing a research postdoctoral fellowship at the University of Wisconsin–Madison, Holick completed a residency in medicine at the Massachusetts General Hospital in Boston. He has been practicing adult and pediatric endocrinology since 1978 and is professor of medicine, physiology and biophysics and director of the Bone Health Care Clinic and the Heliotherapy, Light, and Skin Research Center at Boston University Medical Center. It provides extensive evaluation and treatment programs for children and adults with various metabolic bone diseases including osteoporosis, osteomalacia, stress fractures in young athletic women and men, and minimum trauma and nontraumatic fractures in infants, children and adults with hypermobility syndromes, osteogenesis imperfecta, and Ehlers–Danlos syndrome. He has been director of the General Clinical Research Unit at Boston University for several years. Holick serves as chair of NASA's "Human Health Countermeasures Element" Standing Review Panel, chair of the Endocrine Practice Guidelines Committee for Vitamin D, and editor-in-chief of the medical journal Clinical Laboratory.
=== Deaths === Combined consumption of U-47700 with fentanyl and flubromazepam caused one fatality each in Belgium and Germany, respectively. One death was reported in Ireland and another one in Italy. 17 opioid overdoses and several deaths in the United States had initially been associated with U-47700 in April 2016. As of September 2016 at least 15 fatalities were confirmed. By December 2017, at least 46 fatalities had been associated with the use of U-47700. U-47700 was found in combination with fentanyl during the autopsy of the American artist Prince in 2016.
== Side Effects == There are no significant adverse side-effects of Prajmaline when taken alone and with a proper dosage. Patients who are taking other treatments for their symptoms (e.g. beta blockers and nifedipine) have developed minor transient conduction defects when given Prajmaline.
Sources: en.wikipedia.org
The discovery of nuclear fission occurred in 1938 in the buildings of the Kaiser Wilhelm Society for Chemistry, today part of the Free University of Berlin, following over four decades of work on the science of radioactivity and the elaboration of new nuclear physics that described the components of atoms. In 1911, Ernest Rutherford proposed a model of the atom in which a very small, dense and positively charged nucleus of protons was surrounded by orbiting, negatively charged electrons (the Rutherford model). Niels Bohr improved upon this in 1913 by reconciling the quantum behavior of electrons (the Bohr model). In 1928, George Gamow proposed the liquid-drop model, which became essential to understanding the physics of fission. In 1896, Henri Becquerel had found, and Marie Curie named, radioactivity. In 1900, Rutherford and Frederick Soddy, investigating the radioactive gas emanating from thorium, "conveyed the tremendous and inevitable conclusion that the element thorium was slowly and spontaneously transmuting itself into argon gas!" In 1919, following up on an earlier anomaly Ernest Marsden noted in 1915, Rutherford attempted to "break up the atom." Rutherford was able to accomplish the first artificial transmutation of nitrogen into oxygen, using alpha particles directed at nitrogen 14N + α → 17O + p. Rutherford stated, "...we must conclude that the nitrogen atom is disintegrated," while the newspapers stated he had split the atom.
== Chemistry == Chemically, dipipanone belongs to the class of opioids called the 4,4-diphenylheptane-3-ones. It closely resembles methadone, the only structural difference being the N,N-dimethyl moiety of methadone being replaced with a piperidine ring. Other related compounds with equivalent activity where the piperidine ring has been replaced by other groups, include the morpholine derivative phenadoxone, as well as the corresponding pyrrolidine derivative dipyanone. The synthesis is the same as for phenadoxone, with the exception that piperidine is used in lieu of morpholine. Related compounds with an isoquinuclidine ring such as nufenoxole are also known.
Clocks, watches, and instruments dating from the first half of the 20th century, often in military applications, may have been painted with radioactive luminous paint. They are usually no longer luminous; this is not due to radioactive decay of the radium (which has a half-life of 1600 years) but to the fluorescence of the zinc sulfide fluorescent medium being worn out by the radiation from the radium. Originally appearing as white, most radium paint from before the 1960s has tarnished to yellow over time. The radiation dose from an intact device is usually only a hazard when many devices are grouped together or if the device is disassembled or tampered with.
Khat is a flowering plant native to the Horn of Africa and the Arabian Peninsula. Khat contains a monoamine alkaloid called cathinone, a "keto-amphetamine". This alkaloid causes excitement, loss of appetite, and euphoria. In 1980, the World Health Organization (WHO) classified it as a drug of abuse that can produce mild to moderate psychological dependence (less than tobacco or alcohol), although the WHO does not consider khat to be seriously addictive. It is banned in some countries, such as the United States, Canada, and Germany, while its production, sale, and consumption are legal in other countries, including Djibouti, Ethiopia, Somalia, Kenya, and Yemen.
=== Bile Acid Inducible (bai) Operon === A variety of different biochemical transformations can occur to convert primary bile acids into secondary bile acids, including deconjugation, dehydroxylation, oxidation, and epimerization. Clostridium scindens in particular employs a mechanism called 7ɑ-dehydroxylation. The process of 7ɑ-dehydroxylation is carried out by a gene cluster known as the bile acid-inducible (bai) operon. The bai operon encodes the genes baiB, baiCD, baiE, baiA, baiF, baiG, baiH, and baiI, all of which play integral roles in transforming primary into secondary bile acids.
Sources: en.wikipedia.org
However, the leadership of the United States eventually decided that there was not sufficient international or domestic support for the United States to become directly involved in the conflict. Following the end of the war United States Secretary of State John Foster Dulles denounced Chinese aid to the Việt Minh, and explained that the United States could not act openly because of international pressure, and concluded with the call to "all concerned nations" concerning the necessity of "a collective defense" against "the communist aggression".
==== Codon 72 variations ==== A common human polymorphism in TP53 involves a substitution of arginine for proline at codon 72 of exon 4. Numerous studies have explored the relationship between this variation and cancer susceptibility, yielding mixed results. For instance, a 2009 meta-analysis found no association between the codon 72 polymorphism and cervical cancer risk. Other studies have identified possible associations between the codon 72 polymorphism and various cancers. A 2011 study reported that the proline variant significantly increased pancreatic cancer risk in males. Another study found that proline homozygosity was associated with decreased breast cancer risk in Arab women. Additional research suggested that TP53 codon 72 polymorphisms, in combination with MDM2 SNP309 and A2164G, may affect susceptibility and age of onset for non-oropharyngeal cancers in women. A separate 2011 study linked the polymorphism to an increased risk of lung cancer in a Korean population. However, meta-analyses published in 2011 found no significant associations between the codon 72 variant and risks of either colorectal or endometrial cancer. A study of a Brazilian birth cohort found an association between the arginine variant and individuals without a family history of cancer. Meanwhile, another study reported that individuals with the homozygous Pro/Pro genotype had a significantly increased risk of renal cell carcinoma.
== Occupational exposure == Occupational exposure to PFAS occurs in numerous industries due to the widespread use of the chemicals in products and as an element of industrial process streams. People who are exposed to PFAS through their jobs typically have higher blood concentrations of PFAS than the general population due to their elevated risk for accidental ingestion, inhalation exposure, and skin contact of PFAS. Occupational exposure can occur both during production of PFAS at fluorochemical facilities and in other industries that utilize these chemicals in their processes and products.
=== 1 June === Ukrenergo said Russia launched a barrage of missiles and drones targeting energy facilities in Donetsk, Zaporizhzhia, Dnipropetrovsk, Kirovohrad and Ivano-Frankivsk Oblasts. The private energy company DTEK reported that two thermal power plants were "seriously damaged". The governor of Zaporizhzhia Oblast said that the Dnieper Hydroelectric Station was in a "critical state" following the attacks. Russian officials claimed that over 10 HIMARS rockets were destroyed by air defence in Belgorod Oblast. Fragments of the rockets were recovered and photographed.
Sources: en.wikipedia.org
No. Major drug regulators have not approved GW501516 for treating any medical condition. Products sold as cardarine are typically unapproved research chemicals or supplements, so their contents and safety are not assured.
It is prohibited by the World Anti-Doping Agency as a hormone and metabolic modulator. Athletes who test positive for GW501516 can face sanctions, including suspensions and loss of results.
Cardarine is a common or trade-style name, while GW501516 is the research code for the same chemical entity. Some sources also use Endurobol or GSK-516. The names refer to the same compound, not distinct drugs.
Yes, WADA prohibits cardarine as a PPARδ agonist. It appears on the prohibited list and can be detected in urine or blood. Athletes using it risk sanctions.