Reference standard 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.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
Laboratory studies indicate that GW501516 activates PPARδ, a nuclear receptor involved in fatty acid oxidation and energy metabolism. In rodent experiments, treated animals often showed increased endurance and reduced fat mass. These effects were observed under controlled conditions and do not establish safe or effective use in humans. The exact dose-response relationship in humans remains poorly characterized. Species differences in metabolism can affect how results translate across animals and people.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved for human therapeutic use | No marketing authorization identified in major jurisdictions. |
| Anti-doping class | PPARδ agonist; hormone and metabolic modulators | Listed on the WADA Prohibited List. |
| Common test matrix | Urine | Also blood and tissue in research settings. |
| Typical analytical method | LC-MS/MS | Targets parent compound and metabolites. |
| Major safety signal | Tumor findings in rodents | Human relevance not established; limited human data. |
Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.
Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
Stability of GW501516 depends on form, temperature, light exposure, and moisture. Solid reference material is typically stored frozen or refrigerated in a desiccator and protected from light. Solutions in organic solvents such as dimethyl sulfoxide are often kept frozen in aliquots to reduce freeze-thaw cycling. Aqueous solubility is low, so aqueous stock solutions can be difficult to prepare without cosolvents. Degradation may appear as changes in chromatographic purity or mass spectral signal. Stability studies are needed to establish shelf life for any specific preparation.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
=== Altered platelet function === Congenital Disorders of adhesion Bernard–Soulier syndrome Disorders of activation Disorders of granule amount or release Hermansky–Pudlak syndrome Gray platelet syndrome ADP receptor defect Decreased cyclooxygenase activity Platelet storage pool deficiency Disorders of aggregation Glanzmann's thrombasthenia Wiskott–Aldrich syndrome Disorders of coagulant activity COAT platelet defect Scott syndrome Acquired Disorders of adhesion Paroxysmal nocturnal hemoglobinuria Asthma Aspirin-exacerbated respiratory disease (AERD/Samter's triad) Cancer Malaria Decreased cyclooxygenase activity
Freezing: Using a clear polyester bag, excess air is pushed out and heat sealed with the specimen inside or the specimen can be placed inside polythene bags and sealed with parcel tape. Then it is placed into a normal domestic freezer for at least 14 days at a temperature of −18 °C (0 °F), or for 72 hours if freezing at −30 °C (−22 °F). Anoxia: Small anoxic environments starve the pests of oxygen and are created using sealed barrier films and placing oxygen scavengers and RH buffers inside before sealing. An integrated pest management program is cost-effective over time and the best preventive measure against pests.
== Sexual dimorphism and life cycle == Osedax males are notably smaller than their female counterparts. Between 50 and 100 microscopic dwarf males live inside the tube surrounding a single female and never develop past the larval stage; they produce sperm from yolk reserves. Male dwarfism prevents competition with female Osedax worms for food and space. Conditions that favour dwarfism in male Osedax are:
Sources: en.wikipedia.org
Radon at the United States Environmental Protection Agency Global Radon Map Radon at The Periodic Table of Videos (University of Nottingham) Radon and Lung Health from the American Lung Association The Geology of Radon, James K. Otton, Linda C.S. Gundersen, and R. Randall Schumann Home Buyer's and Seller's Guide to Radon An article by the International Association of Certified Home Inspectors (InterNACHI) Toxicological Profile for Radon, Draft for Public Comment, Agency for Toxic Substances and Disease Registry, September 2008
== Organizations == SST Inc. also known as ShotSpotter Inc. Silicon Storage Technology, Inc, former US semiconductor manufacturer School of Science and Technology, high school in Oregon, US School of Science and Technology, Singapore Special Security Team, a counter-terrorist unit of the Japanese Coast Guard
== Release details == 1907, France, L'illustration, Pub September–November 1907, magazine serial (in French) 1908, France, Editions Jacques Lafitte (ISBN NA), (First edition) (in French) 1934, UK, Oxford University Press ISBN 0-19-832345-X, (in French) 1977, UK, Dover Publications ISBN 0-486-23460-6 1978, UK, Remploy ISBN 0-7066-0759-7 1996, US, Books on Tape ISBN 5-557-12771-2 1996, US, Buccaneer Books ISBN 0-89966-141-6 1997, UK, Dedalus Ltd ISBN 1-873982-38-0 2002, US, Indypublish.com ISBN 1-4043-2003-2 2002, US, Indypublish.com ISBN 1-4043-2002-4 2004, UK, Thorndike Press ISBN 0-7862-6991-X 2005, US, Kessinger Publishing ISBN 0-7661-9366-7 2006, UK, Blackstone Audiobooks ISBN 0-7861-7523-0, audio book (MP3 CD) 2006, UK, Dover Publications ISBN 0-486-44928-9 2009, US, Black Coat Press ISBN 1-934543-60-8
==== Thermoelectrics ==== Adding 0.6% graphene to a mixture of lanthanum and partly reduced strontium titanium oxide produces a strong Seebeck at temperatures ranging from room temperature to 750 °C (compared to 500–750 without graphene). The material converts 5% of the heat into electricity (compared to 1% for strontium titanium oxide.)
Sources: en.wikipedia.org
No. Cardarine has not received approval for human therapeutic use in major jurisdictions. It remains an investigational compound.
It is classified as a PPARδ agonist on the WADA Prohibited List. Anti-doping laboratories can detect it and its metabolites in urine. Its use is banned in competition and usually out of competition.
Rodent studies reported increased tumor incidence at multiple sites. The human relevance remains uncertain, but the findings contributed to discontinuation of development. No long-term human cancer data are available.
Rodent studies reported increased endurance and fat oxidation after GW501516 exposure. Long-term studies also found higher rates of some tumors, which led to halted development.