The Complete Guide To CBD and Cannabinoid Product Lab Testing For Quality


cannabinoid product testing

Laboratory testing of cannabidiol (CBD) and cannabinoid products tends to play an important role in the process of manufacturing, as it helps in improving the efficiency of the final product. In addition to this, testing leads to the demonstration of compliance, alongside identifying errors that could affect the quality of the complete product (Phyto Vista Laboratories, 2021) (1) before distribution to consumers.

On the other hand, specialist third-party laboratory testing provides financial benefits to cannabis businesses by reducing overheads required for in-house production and decreasing the time to market of products. However, companies that do not adhere to the best testing practices can increase the number of business risks, such as lower product quality, product recalls, lack of accreditation, and damaged company reputation. The CBD market in the United Kingdom (UK) is thriving due to the high consumer demand, whereas the regulation and legislation are considerably low. The aforementioned aspect has exposed the industry to an increased risk for exploitation in the presence of non-reputable parties (PhytoVista Laboratories, 2021) (1).

Concurrently, the hemp growing industry of the region is currently unable to compete with the global market, mainly due to the legal restrictions on the plant from which CBD is obtained. This has pushed manufacturers and retailers in the UK to obtain CBD extracts from other countries through suppliers. To overcome the challenge, companies producing CBD can ensure protection by performing testing of samples before buying larger volumes of raw material (PhytoVista Laboratories, 2021) (1).

In this regard, the article is presented with the focus on the type of testing carried out in labs and tests that are reserved for CBD and cannabinoid products. Furthermore, cannabinoids are discussed in detail to promote an understanding of these compounds and the importance of detecting UK-controlled cannabinoids. Pesticide lab testing is encompassed with the explanation of different testing protocols and human harm potential. Examples are provided of CBD companies that have been investigated for poor practices that have led to adverse outcomes. A detailed discussion on pollutants is provided to elaborate the significance of lab testing, while a conclusion is drawn to highlight the gold standards for CBD products.

Types of Lab Testing

There are CBD products and then there are the lab-tested CBD oil products. With the hemp industry in the dark right now, the lack of government regulations has allowed the infiltration of dangerous synthetic compounds. Even pure hemp extracts can vary in their THC and cannabinoid content (Coulter and Wagner, 2021) (2).

Regarding the current cannabis decriminalization in various countries, researchers and governmental bodies are investing pronounced efforts to ensure efficient testing procedures for CBD and cannabinoid products. One of the major concerns related to the testing of these products is safety. It is noted that cannabis can contain different contaminants, which include heavy metals, pesticides, mycotoxins, and residual solvents. To ensure the cannabis hemp strain with the correct properties is used and test the presence of terpenes and cannabinoids for the determination of their effect and potency, the following tests are performed (Labcompare, 2021) (3):

  1. Sample preparation: For testing cannabis, sample condition is viewed before starting a test. Labs conduct a test by taking cannabis products in various forms, such as extracts, dried flowers, cosmetics and edibles. Each type of product requires a different routine of sample preparation.
  2. Cannabinoid analysis: Cannabinoids are checked for their presence, such as CBD, tetrahydrocannabinol (THC), CBC, CBG, Delta 8 THC and CBN. The commonly used methods for the analysis of these compounds are High-Performance Liquid Chromatography (HPLC) and Gas Chromatography (GC).
  3. Terpene analysis: The prominent property of terpenes is fragrance, alongside some medicinal properties singularly or when used with other terpenes to form cannabis strain specific profiles. The methods used to detect the quality of terpenes are gas chromatography/flame ionization detection (GC/FID), gas chromatograph-mass spectrometer (GC-MS), and HPLC.
  4. Strain analysis: It is carried out with the aid of polymerase chain reaction (PCR).
  5. Detection of heavy metals: Heavy metals include mercury, cadmium, copper, lead, arsenic, and tungsten, which can be traced in the products of cannabis. The significant tool to rule these out is mass spectrometry (MS). In addition to this, methods include inductively coupled plasma mass spectrometer (ICP MS), inductively coupled plasma atomic emission spectrometry (ICP-AES), atomic absorption spectrophotometry (AAS), and inductively coupled optical emission spectrometry (ICP-OES). The less commonly integrated method is liquid chromatography (LC). However, the test provides efficient results for arsenic detection.
  6. Pesticide testing: Pesticides are frequently used by growers and farmers, which in turn, contributes to increased chances of toxic effects when consumed. To detect pesticides, researchers often use GC-MS, HPLC, and LC-MS. Before performing LC/MS/MS, researchers use the QuEChERS approach for the preparation of the sample.
  7. Residual solvents: Several solvents are used to extract from cannabis, which include ethanol, acetone, butane, propane, and benzene. These solvents can also be found in the final products, while the analysis of residual solvents is carried out by coupling headspace analysis with the technique of GC. Other commonly used approaches are GC-MS and GC-FID.

Mycotoxins and microorganisms: Contamination in cannabis can occur due to the presence of microorganisms, which involve mildew, mould, yeast, and bacteria. Sometimes, fungal toxins are also found, such as aflatoxins and mycotoxins. Therefore, to obtain a prompt visual assessment of the microorganisms, a dissecting microscope is used. For an in-depth analysis, advanced methods are required and PCR is used to conduct the test. It helps in examining bacterial strains and toxins. In addition to this, Petri film analysis can be used, which is a traditional method for bacterial strain detection.

CBD and Cannabinoid Lab Testing

cannabinoid cbd potency profile lab testing

In the UK, cannabis use for certain medical purposes has been legalized since 2018. Specialist doctors can prescribe it for specific health issues based on the case. However, another type of cannabis product has become popular recently over the counter (BBC, 2021) (9). It has been reported that the consumer demand for CBD products has increased during the lockdown period (Morrison, 2021) (10). The UK has developed the most evolved regulatory framework across the globe. The United States-based companies also have to ensure that they follow the CBD laws to supply and sell their products to the UK (Bond, 2020) (11). It can be stated that approximately 250,000 individuals in Britain use products with cannabis as they are attracted by the claims of reducing anxiety, stress, insomnia, and mitigating the symptoms of cancer, autism, and epilepsy (BBC, 2021) (9). However, these medically prescribed CBD products are confused with OTC products that have no research or trials to able to make any claims and therefore must only be used as food supplements. 

These hemp extracted products are usually sold in liquid form with CBD as the primary compound due to its non-psychoactive property. CBD use does not lead to dependency effects or the feeling of being high, whereas THC is one of the major psychoactive compounds in cannabis. Companies manufacturing and/or selling hemp CBD products in the UK must make sure that the amount of THC should be under the permitted limit of 0.2% (BBC, 2021) (9).

To assess the quality and contents of the CBD product in every batch, a certificate of analysis (CoA) is conducted. CoA is a lab test from a third party confirming that the cannabis products meet the marketed specifications. CoA for CBD products shows the variety and concentrations of cannabinoids in the product. CoA gives information about an important parameter that is the limit of quantification (LOQ). It is the lowest concentration of measure that can be identified with repetitive tests. Results show if there are any traceable or non-quantifiable amounts of cannabinoids in the products.

Since people are self-treating themselves with over-the-counter cannabis-based products, a Dutch cannabis expert, Dr. Arno Hazekamp, conducted a test to measure the content of CBD in the products to check if they provide what they are claiming. He selected 12 products that are available online and over the counter easily. The results showed that three out of twelve products contained approximately half the concentration of the CBD that has been mentioned on the label. The European Food Standards Agency (EFSA) recommends the limit for THC as a daily dose to be 70 mg for an adult since it is nearly impossible to completely exclude THC from CBD products. Love CBD is one of the providers that exceeded the THC limit in the test (BBC, 2021) (9). Love CBD offers CBD products to the population in Europe and the UK. Hence, the company under investigation was found to be violating the UK government regulation on CBD products. One major issue is the lack of standard and internationally organized tests due to which the results vary in each lab. Hence, the government has to take action for standardizing tests.

The growing popularity of CBD has led to a changing reality of what “drug use” means. Multiple emerging medical studies have discovered the benefits of CBD, resulting in a global market of $4.6 billion in 2018 (Cowen, 2019) (4).

CBD and cannabinoid lab testing is done to check the makeup of products, ranging from full-spectrum, broad-spectrum, isolate cannabinoids and bespoke formulations. Testing of cannabinoids is especially important to verify the product against labelled quantities, ensure correct potency of product, keep products legal and to protect consumers against any unwanted consumption of compounds.  For example, athletes are prohibited to use any cannabinoids other than CBD.  Similarly, to ensure products are legal, testing is used to ensure the correct levels of controlled cannabinoids in a product are within the legal 1mg allowance per container. Cannabis plants contain over 80 cannabinoids, however the most common detectable cannabinoids found in a hemp extract other than CBD are: CBC, CBG, CBN, delta 8 THC, and delta 9 THC (Moderncanna Labs, 2021) (5).

Cannabinoid profile testing or cannabinoid potency testing identifies the concentration of active cannabinoids in a product (Moderncanna Labs, 2021) (5). When developing a CBD product, companies follow adequate extraction processes to create the desired cannabinoid profile, however cannabinoid profile testing is used to verify the product has met the required extract specification before being released to the consumers and sellers.

As highlighted earlier, HPLC and GC are the commonly used techniques to analyse the concentration and presence of cannabinoids in a product. In the HPLC technique, the sample is extracted into a solvent after which isolation of target compound is completed, followed by measurement of its concentration through an ultra-violet detector.  On the other hand, a similar process can be used through gas chromatography, here the sample is instead heated when using this technique (Lazarjani et al., 2020) (6). With the help of these techniques, the cannabinoids that can be typically tested for, are: 8-THCV, 10-THCV, EXO-THC, CBT, THCA-A, THCV, -THC, CBCA, CBD, CBC, 8-THC, CBDVA, CBDA, CBN, CBDV, CBL, CBG, CBGA, CBNA, THCVA.

Not only does cannabinoid testing help identify deviation from the labelled components but also to ensure that consumers do not under or overdose when using such products.

The Consequences Of Not Accurately Testing Cannabinoid Products

A challenge for some consumers is having confidence in buying products  where the outcome of using hemp products could have severe consequences. Common amongst general users is their decision whether or not to use products that contain THC. Hence, the most desired product is usually a broad spectrum CBD or a pure CBD isolate product.  Although the most heavily discussed cannabinoids are THC and CBD, some users such as tested athletes may have a requirement to use CBD isolate products as any other cannabinoid is not permitted by the WADA rules.

However without proper testing practices, these CBD products may be contaminated with THC or other unwanted cannabinoids, possibly leading to a reaction to a compound, athlete ban or dismissal from a job.

The threshold for detecting THC in the traditional urine drug test detects the THC content when the amount of THC is greater than 50 ng / mL (Macherone, 2021) (7).

So, while the chances of a pure CBD producing a positive THC result are slim, a person can still get a positive result on a urinalysis if the amount of THC consumed exceeds 50 ng / ml (Macherone, 2021) (7), due to low level contamination not picked up by inefficient product cannabinoid testing.

Cannabinoid Drug Testing

CBD products can also produce a positive THC test if certain reagents are used during GC-MS analyses. In one study, when perfluorinated anhydrides and perfluoroalcohols were used as reagents, the acid-base converted CBD to THC, leading to a false-positive result for THC.

If an athlete claims that a failed drug test is solely due to the use of CBD, they can confirm it using a more accurate method, such as GC-MS or RP-HPLC.

Many labs now use more accurate technique known as high-performance liquid chromatography to confirm drug tests. More optimized methods, such as reverse-phase high-performance liquid chromatography (RP-HPLC), are more reliable and faster (with results in 10 minutes) to detect eight different cannabinoids, including CBD. RP-HPLC uses acetonitrile and water as agents in a ratio of 1: 1.9. However, laboratories using GC-MS are still common, as this method is considered the gold standard for broad-spectrum drug testing.

UK Controlled Cannabinoids

uk testing controlled cannabinoids

The UK government has provided guidance regarding analytical limits to control in cannabinoid specified products containing cannabidiol (CBD). The relevant legislation advises cosmetic and food companies that use CBD in supply and production processes. The problem with the use of CBD is that the hemp extract does include psychoactive cannabinoid ingredients when using full or broad spectrum extracts. Hence, the UK Misuse of Drugs Act (MDA) and its related regulations prohibit certain psychoactive cannabinoid substances based on the part of the plant that has been used for extraction. The limit for controlled cannabinoids or controlled drugs is 1 milligram in the UK (Department for Business, Energy, and Industrial Strategy, 2021) (8).

However, the difficulty is how to interpret this amount in a product. The new guide discusses that the applicable measuring unit is the bottle or pack for the 1 mg threshold. The CBD product might consist of several psychoactive cannabinoids that when integrated might exceed the 1 mg limit. Hence, it is significant to detect every psychoactive ingredient at lower concentrations.

There are many product novel food formats that contain hemp extract such as nutritional capsules, oral liquids, oral sprays, and gummy bears. The minimum detectable concentration for an individual prohibited psychoactive cannabinoid is < 0.185 mg/g for nutritional capsules, < 0.00833 mg/ml for oral liquids, < 0.0028 mg/ml for oral sprays, and < 0.0005 mg/g for gummy bears. In addition, the marketed range for cosmetic products with CBD hemp extract is 15g (< 0.0055 mg/g) for lip balm, 30 ml (< 0.0028 mg/ml) for a face wash, and 200 ml (< 0.0004 mg/ml) for body lotion (Department for Business, Energy, and Industrial Strategy, 2021) (8).

Thus, companies have to use a sensitive measurement system that can detect lower level concentrations of cannabinoids to follow the regulations. The cannabinoids prohibited by the UK authorities include the following cannabinoids:

  • Cannabinol-C1
  • Cannabinol-C2
  • Cannabinol-C3
  • Cannabinol-C4
  • Cannabinol-C5
  • Cannabinol methyl ether-C5
  • Delta-8-tetrahydrocannabinol
  • Trans-delta-9-tetrahydrocannabinol-C5
  • Cis-delta-9-tetrahydrocannabinol-C5
  • Delta-9-tetrahydrocannabinol-C1
  • Delta-9-tetrahydrocannabinol-C3 (Delta-9-tetrahydrocannabivarin)
  • Delta-9-tetrahydrocannabinol-C4

Pesticide Lab Testing

cbd pesticide lab testing

Pesticides are substances developed technologically to be used on crops and plants. They are classified by different types such as herbicides, insecticides, and fungicides. Despite being widely used, pesticides can be toxic and harmful to human health and the environment. A pesticide is any substance that is intended to prevent, destroy, repel, or mitigate any "pest". In this way, they serve to kill organisms that proliferate in an unbalanced environment (Mahmood et al., 2016) (12). There are different types of pesticides for each specific situation. Some of them are:

  • Algaecides: used to kill and retard algae growth;
  • Antimicrobials: kill microorganisms;
  • Biopesticides: made from living organisms;
  • Fungicides: used to kill fungi;
  • Herbicides: inhibit plant growth;
  • Insecticides: used to kill insects;
  • Mollusks: used to kill slugs, snails, and other mollusks;
  • Pesticides: control “pests”, can be of natural origin or not;
  • Rodenticides: used to kill rodents such as rats.

All pesticides carry some risk depending on the toxicity of the ingredients and the amount of exposure. Some of them are more toxic than others, and, depending on their composition, pesticides can contaminate the soil, atmosphere, and groundwater in addition to harming non-target organisms such as plants, animals, and people.

Blair et al. (2015) (13) identified that the use of pesticides can pose risks to human health. This can happen when they are used inside or around homes and gardens, when working directly with the products, or even when they are used in food. Moreover, some companies manufacture to organic farming standards, which means no pesticides are used. Considering the risk to health and claims by companies, it is important to assure that the pesticides are not present in CBD cosmetics or novel food products. Therefore, pesticide lab testing is a specific test used to trace the number of pesticides in end products.

For protecting consumers, pesticide residues are subjected to strict legislation around the world. Maximum Residue Limits (MRLs) are the greatest amount of a specific pesticide residue allowed in any product or food. Across the globe, MRLs values differ from country to country (Ambrus & Yang, 2016) (14). It is the responsibility of food manufacturers exporting products to meet the limits of pesticides residues of other countries where they are exporting.

The pesticide residue analysis process generally includes residue extraction, a cleaning procedure for removing other ingredients, and a systematic procedure for identification and measuring the quantity of pesticides residue. Generally, pesticide residues are analyzed with the help of mass spectrometry coupled with gas chromatography (GC-MS) and liquid chromatography (LC-MS) for volatile and non-volatile compounds respectively (Stachniuk & Fornal, 2016 (15); Hadian et al., 2019 (16)). These two tests are used to quantify and identify pesticides in a sample. The extracted samples are then processed through an analyser according to the manufacturer's instructions. Using these techniques, pesticide residue analysis allows you to identify and quantify each pesticide in the sample compared to a known pesticides’ matrix. To get the best output, the process needs the utilization of reference standards of high-quality and reproducible conditions.

The common types of pesticides that are used on crops in Europe are organochlorine, organophosphorus, pyrethroids, carbamates, and triazines. In humans, long-term exposure to organochlorines affects the endocrine system and nervous system. Indirect or direct exposure to pesticides leads to stimulation of steroid and drug metabolism and neuromuscular disorder (Jayaraj et al., 2016) (17). After exposure to organophosphates, individuals can develop nervous system conditions, for example, neuropathy and muscle weakness (Adeyinka et al., 2018) (18). Other effects of organophosphorus long-term exposure include depression, disorientation, loss of appetite, loss of memory, anxiety, and confusion.

Considering the effects of pyrethroids, acute exposure leads to skin, eyes, and respiratory irritation. Whereas long-term exposure affects male fertility and prenatal development (Saillenfait et al., 2015) (19). Carbamates are also one of the most widely used pesticides. Ingestion of carbamates can lead to sweating, diarrhoea, stomach cramps, and shaking. Exposure for long periods can lead to weight loss, weakness, and loss of appetite (Dias et al., 2015) (20). Triazines are considered as high irritants to the eyes and mild irritants to the skin. They are regarded as human carcinogens if exposed for a long duration (Mostafalou & Abdollahi, 2017) (21). Hence, the companies making CBD products have to make sure that their products do not contain pesticides.

Cannabis plants absorb the pesticides sprayed on the plant or applied to the soil. The presence of pesticides in CBD products is a prevailing problem. In 2016, a report from Steep Hill Labs indicated that 84.3% of cannabis products contain pesticides residue (Also Organics, 2020) (22). The findings from CBS Austin and Ellipse Analytics in 2019 revealed that 70% of the top-selling CBD products that are available over the counter or online have tested positive for chemical pesticides (Harris, 2019) (23).

Pollutants: Mycotoxins - Aflatoxins and Ochratoxin Lab Testing

cd pollutant lab testing

Mycotoxins are substances produced by several hundred species of moulds that can grow on food under certain conditions of humidity and temperature. Mycotoxins pose a serious risk to human and animal health. Mycotoxins are naturally occurring (non-anthropogenic) chemical compounds in the secondary metabolism of some genera of fungi. The most important are the toxins produced by moulds of the genera Aspergillus, Fusarium, and Penicillium (da Rocha et al., 2014) (24).

The main mycotoxins occurring in grains and by-products used in animal nutrition are aflatoxins and ochratoxin A. Mycotoxins are secondary toxic metabolites produced by filamentous fungi. Fungi grow and proliferate well in grains under ideal conditions of temperature, humidity, and the presence of oxygen. The testing for the presence of these products is important because mycotoxins are harmful to the health of human beings. A study by Freire and da Rocha (2017) (25) proposed that the harmful effects of mycotoxins can be chronic or acute leading to issues such as respiratory problems, convulsions, gangrene, protein metabolism alterations, reduction of immunity, and liver cancer. Ostry et al. (2017) (26) indicated that mycotoxins are carcinogens, which means that long-term exposure to mycotoxins can increase the likelihood of developing cancer in an individual.

Ochratoxin A is a mycotoxin produced by some species of filamentous fungi belonging to the genera Aspergillus and Penicillium and is, among all ochratoxins, the most toxic and therefore the most relevant. It has carcinogenic, nephrotoxic, teratogenic, immunotoxic, and neurotoxic properties. Ochratoxin A is associated with nephropathy in humans, and there may be a relationship between exposure to this toxin and Endemic Balkan Nephropathy, a progressive disease characterized by reduced renal function, which is often fatal (Malir et al., 2016) (27). Two primary methods are available for the analysis of ochratoxin. The HPLC in combination with mass spectroscopy or fluorescence detection method for detecting mycotoxins is time-consuming and both the HPLC and enzyme-linked immune-sorbent assay (ELISA) methods require expensive laboratory equipment. 

Aflatoxins are produced by fungi of the Aspergillus genus and reported as hepatotoxic, mutagenic, immunosuppressive, and neoplastic. They are regarded as mutagens and poisonous carcinogens. Depending on the amount ingested, frequency of ingestion, and age of the individual, they may be related to cirrhosis, liver necrosis, encephalopathy, and increased susceptibility to hepatitis B. Among the aflatoxins, those called B1, G1, B2, and G2 stand out, B1 especially has high hepatotoxicity. The biotransformation of aflatoxins occurs mainly in the liver and different enzymes can act in detoxification (Coppock et al., 2018) (28). Aflatoxins have an important carcinogenic action that affects humans and animals. The liver is the main organ affected by it. To detect the presence of aflatoxins in food products or any other products, the are several methods for testing such as ELISA, electrochemical immunosensor, mass spectroscopy, HPLC, and thin-layer chromatography (TLC), as highlighted by Wacoo et al. (2014) (29).

Aflatoxins B1 and B2 are mycotoxins produced by Aspergillus flavus and Aspergillus parasiticus. Aflatoxin B1 is the factor that most hinders fetal development, with the greatest capacity to cause or accelerate cancer, and it is also the type of aflatoxin that causes the greatest sudden and permanent changes in genes, among these, it can induce a specific mutation in codon 249 of the P53 suppressor gene, related to tumour genesis. Aflatoxin B1 (AFB1) is the one with the highest potency and carcinogenic activity at the hepatic, fetal teratogenic, and mutagenic cell cycle levels. Aflatoxin B2 is similar to B1, except for the saturation of the first furan ring; it is carcinogenic but less toxic and less frequent than B1 (Kowalska et al., 2017) (30).

Aflatoxin G1 and G2 are also produced mainly by Aspergillus parasiticus that are present on plants and foods (Solter & Beasley, 2013) (31). Aflatoxin G1 is a procarcinogen, which is linked with phase 1 and phase 2 metabolism in the liver and other tissues. The toxicity of aflatoxin G1 is similar to B1 with acute toxicity being greater than B2 but higher than B1. Aflatoxin G1 and G2 are less potent than B1. Overall, all of them affect the liver mainly and are fatal for human health (Bbosa et al., 2013) (32).

Ergot alkaloids are mycotoxins produced by many species of Claviceps genus fungi. In the growing season, this group of compounds attacks a broad variety of grass species. Ergot alkaloids are highly toxic, suppress prolactin secretion, affect cardiovascular function, increase uterine motility, and can lead to weak and rapid pulse, decreased circulation, vomiting, nausea, and coma (Hodgson, 2012) (32).

In the UK, there is legislation to protect the consumers of CBD products from mycotoxins such as aflatoxins and ochratoxin A. The maximum levels of mycotoxins are established in EU Regulation 1881/2006 for Northern Ireland and retained EU Regulation 1881/2006 for Wales and England. Regulations for sampling and analysis for mycotoxins in products are also regulated with certain legislation to make sure that samples are fairly taken and assessed with authentic laboratories (Food Standards Agency, 2021) (34).

Residual Solvent Lab Testing

cbd residual solvent lab testing

Residual solvent testing is used for the determination of the presence of residual solvents or other impurities and if they are present in harmful quantities. For the specific extraction process, solvents are utilized for the isolation of cannabinoids from the plant. In the process of cannabis extraction, several solvents are used such as carbon dioxide, ethanol, butane, xylene, and benzene (Winfield, 2019 (35); Cyrus, n.d. (36)). For consumer safety and to meet EU regulations, solvents must be removed from the product before consumption. There are several adverse effects of these solvents that are discussed below in detail.

This means that consumers' safety and regulations make it mandatory to remove residual solvents. Hence, residual solvent testing is a significant process. The most common technique used to detect residual solvents in cannabis and hemp is GC-MS (Clifford et al., 2021) (37), as it recognizes the precise composition of the sample.

The effects of the most commonly used solvents for cannabis extraction on human health are presented below.

  • Carbon Dioxide: liquid carbon dioxide (CO2) has been used as a solvent for organic compounds due to its less toxic property as compared to other solvents.
  • Ethanol: it is a class 3 residual solvent, which means low toxic potential for human beings. Ingesting a small amount of ethanol cannot be harmful. However, inhaling ethanol can be dangerous as it can cause cravings, tolerance, and dependence.
  • Butane: the harmful effects of butane are being argued over in the research community as they are unsure about its long-term effects. Nonetheless, some studies have reported cardiac issues and organ failure as a result of extremely high exposure to butane.
  • Xylene: it is a Class 2 solvent, which means they are toxic or carcinogenic in nature. Hence, the amount of these should be limited. Vapours of xylene can affect the nervous system.
  • Benzene: it is a Class 1 solvent, which makes it very harmful for human health. such solvents should be avoided as they are human carcinogens and cause environmental hazards. Benzene can negatively affect immune, neurological, and bone marrow function (Labplex, 2021) (38).

It has been revealed in the report by the Centre for Medicinal Cannabis (CMC) that CBD products that used the solvent extraction method had solvent residues over the E’s limit for a food product. The report also revealed that 60% of CBD products available online and over the counter in the UK are mislabelled (PhytoVista Laboratories, 2019) (39).

Heavy Metals Lab Testing

cbd heavy metal lab testing

The adjective “heavy” is literal, a result of these materials being denser – that is, their atoms are closer together. In contact with the body, these metals end up attracting to themselves in two essential elements of the body: proteins and enzymes. Eventually, they join to some of these elements, preventing them from working, which can even lead to death. Heavy metals also bind to cell walls, making it difficult to transport nutrients (Mahurpawar, 2015) (40). Mercury, lead, cadmium and arsenic are the most dangerous metals to human health. Hence, the testing regarding the detection of these metals is important for human safety. The most commonly used techniques to detect heavy metals are flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry, inductively coupled plasma mass spectroscopy (ICP-MS), and HPLC coupled with UV-Vis-detectors (Shimizu et al., 2019) (41). The adverse effects on the human body of the most common heavy metal are explained below.

Arsenic is a semi-metallic chemical, which is carcinogenic (pulmonary), teratogenic and mutagenic. Long-term exposure to arsenic can cause skin lesions and cancer. It has been found that arsenic exposure is linked to diabetes and cardiovascular diseases. In early childhood, exposure can affect cognitive development and can cause death. Ingestion of large doses (70 to 180 mg) can be fatal whereas acute arsenic ingestion can damage the mucous membranes of the gastrointestinal tract, causing irritation, blistering, and even scaling (Abdul et al., 2015) (42). Additionally, lead is a heavy metal whose long-term exposure is linked to increased blood pressure, kidney damage, reproductive problems, and even brain damage. A very high amount of lead can result in death. Children are at higher risk of lead exposure or lead poisoning, resulting in hearing problems, slower growth, learning, and behavioural problems, and anaemia (Matta & Gjyli, 2016) (43).

In addition, Cadmium is also a toxic metal, ubiquitous, and very stable in the environment. The cadmium in the human body has no organic function. When a person absorbs it, it competes with zinc and copper, hindering the absorption of these nutrients. Then it builds up in the kidneys and arteries and, in the long run, can be cancerous. It also causes metabolic problems, bone decalcification, and rheumatism. Inhalation of high doses can cause acute intoxication, which causes pulmonary oedema (Mahurpawar, 2015) (40). Furthermore, mercury is a liquid metal and is found in the environment in low amounts. Inhalation of high concentrations of metallic mercury vapor can damage the lungs, and chronic inhalation leads to neurological disorders, memory problems, skin rashes, and kidney failure (Matta & Gjyli, 2016) (43)

The CMC report indicated that one of the sampled CBD products contained heavy metal cyclohexane in quantity greater than the permitted limit in a food product (PhytoVista Laboratories, 2019). Harris (2019) (23) also found that 70% of CBD products in the market had pesticides or heavy metals. This is an alarming figure, indicating that the companies are not following the regulations, which makes the products potentially harmful for people.

Terpenes Lab Testing

cbd terpenes lab testing

Terpenes are the compounds responsible for the smell of plants. They are found abundantly in cannabis. Cannabinoids when combined with terpenes are more enhanced as compared to their effectiveness alone. This is referred to as the entourage effect. Cox-Georgian et al. (2019) (44) proposed that cannabinoids and terpenoids work together effectively to reduce inflammation, reduce mental health problems, and relieve pain.

To make sure that either the product does or does not contain terpenes, testing for terpenes is conducted. With the help of this testing, the consumers will get an idea of the hemp extract quality through its rich terpene profile. Moreover, some people or pets have an intolerance to terpene(s), so the test ensures that a product does not contain terpenes. When a specific cannabis strain profile is used (e.g. White Widow, Granddaddy Purple, Pink Kush, Purple Haze, Pineapple Express, or Sour Diesel), that the terpene profile can be confirmed through test analysis to ensure that the CBD product has the right therapeutic effects such as sleep, energetic, relaxation, pain relief, anxiety relief, inflammation, nausea, mood, etc.

For analysing the presence of terpenes and cannabis strain terpene profiles in a CBD product, the most commonly used technique is gas chromatography.

Conclusion and Gold Quality Standards for CBD Product Lab Testing

From this article discussion, it can be concluded that lab testing is a significant process to make sure CBD products that are easily available over the counter have been correctly labelled through verification of the product content. Moreover, there is a likelihood of the presence of several components that can be harmful to human health such as pesticides, mycotoxins, residual solvents, and heavy metals. Therefore, lab testing is very important to understand the constituents of the products and to ensure that there is no risk for human consumption.

Given the presence of many CBD products in the UK market and the lack of standardized laboratory testing for measuring CBD content, the UK government has started a cannabinoid ring trial in which the assessment of performance and accuracy of various laboratories was evaluated. Out of 35 laboratories who participated, 32 provided results showing the same expected quantity of CBD in the given samples and the same interpretation of the results in the report, which is satisfactory. However, Controlled cannabinoid measurement varied among the laboratories (Hambidge, 2021)(45).

The findings of this study are beneficial for CBD products providing a direction that CBD content can be measured accurately in the UK. The discussion in the article proves that providing a cannabinoid COA (Certificate of Analysis) is not enough. Companies selling and manufacturing CBD products should follow the gold standard and provide all 5 types (cannabinoids, terpenes, pollutants, heavy metals, and residual solvents) COA’s for CBD products to be considered premium products.

RUDERALEX® Gold Standard Lab Testing for Quality

ruderalex cbd lab testing

Now that you know the importance of the different types of testing, with RUDERALEX® CBD products you can be sure to know that you are getting a premium product, with the best ingredients and quality verified by our rigorous testing procedures. 

Cannabinoid Profile/Potency Lab Tested

cbd lab test



Terpenes Tested

terpenes lab test


Pollutant Tested

pollutant lab tested


Heavy Metal Tested

heavy metal lab tested


Pesticide Tested

pesticide lab tested





  1. PhytoVista Laboratories. (2021). The Importance of Testing CBD Products.
  2. Coulter, C., & Wagner, J. R. (2021). Cannabinoids in oral fluid: limiting potential sources of cannabidiol conversion to Δ9-and Δ8-tetrahydrocannabinol. Journal of analytical toxicology.
  3. (2021). Cannabis Testing and Analysis.
  4. (2019). Cowen’s Collective View of CBD.
  5. Moderncanna Labs. (2021). Cannabinoid Testing.
  6. Lazarjani, M. P., Torres, S., Hooker, T., Fowlie, C., Young, O., & Seyfoddin, A. (2020). Methods for quantification of cannabinoids: a narrative review. Journal of Cannabis Research, 2(1), 1-10.Macherone, A. (2021). Cannabinoid Detection and Quantitation. Cannabis Laboratory Fundamentals, 171-189.
  7. Department for Business, Energy, and Industrial Strategy. (2021). Government Chemist Guidance Analytical Limits for Controlled Cannabinoids in Specified Products Containing Cannabidiol (CBD) Michael Walker and Ian Axford.
  8. (2021). What’s really in cannabis-based health products?.
  9. Morrison, O. (2021). UK CBD market ‘the world’s second largest behind US’, association body claims.
  10. Bond, D. (2020). CBD Advertising in the UK – the basics.
  11. Mahmood, I., Imadi, S. R., Shazadi, K., Gul, A., & Hakeem, K. R. (2016). Effects of pesticides on environment. In Plant, soil and microbes (pp. 253-269). Springer, Cham.
  12. Blair, A., Ritz, B., Wesseling, C., & Freeman, L. B. (2015). Pesticides and human health. BMJ, 72(2).
  13. Ambrus, A., & Yang, Y. Z. (2016). Global harmonization of maximum residue limits for pesticides. Journal of agricultural and food chemistry, 64(1), 30-35.
  14. Stachniuk, A., & Fornal, E. (2016). Liquid chromatography-mass spectrometry in the analysis of pesticide residues in food. Food Analytical Methods, 9(6), 1654-1665.
  15. Hadian, Z., Eslamizad, S., & Yazdanpanah, H. (2019). Pesticide residues analysis in Iranian fruits and vegetables by Gas Chromatography-Mass Spectrometry. Iranian journal of pharmaceutical research: IJPR, 18(1), 275.
  16. Jayaraj, R., Megha, P., & Sreedev, P. (2016). Organochlorine pesticides, their toxic effects on living organisms and their fate in the environment. Interdisciplinary toxicology, 9(3-4), 90.
  17. Adeyinka, A., Muco, E., & Pierre, L. (2018).
  18. Saillenfait, A. M., Ndiaye, D., & Sabaté, J. P. (2015). Pyrethroids: exposure and health effects–an update. International journal of hygiene and environmental health, 218(3), 281-292.
  19. Dias, E., e Costa, F. G., Morais, S., & de Lourdes Pereira, M. (2015). A review on the assessment of the potential adverse health impacts of carbamate pesticides. Topics in public health, 197-212.
  20. Mostafalou, S., & Abdollahi, M. (2017). Pesticides: an update of human exposure and toxicity. Archives of toxicology, 91(2), 549-599.
  21. Also Organics. (2020). CBD and Pesticides.
  22. Harris, Z. (2019). Report Says 70% of CBD Products Are Contaminated with Heavy Metals or Pesticides.
  23. da Rocha, M.E.B., Freire, F.D.C.O., Maia, F.E.F., Guedes, M.I.F. and Rondina, D., 2014. Mycotoxins and their effects on human and animal health. Food Control, 36(1), pp.159-165.
  24. Freire, F. D. C. O., & da Rocha, M. E. B. (2017). Impact of mycotoxins on human health. Fungal Metabolites, 239-261.
  25. Ostry, V., Malir, F., Toman, J., & Grosse, Y. (2017). Mycotoxins as human carcinogens—the IARC Monographs classification. Mycotoxin research, 33(1), 65-73.
  26. Malir, F., Ostry, V., Pfohl-Leszkowicz, A., Malir, J., & Toman, J. (2016). Ochratoxin A: 50 years of research. Toxins, 8(7), 191.
  27. Coppock, R. W., Christian, R. G., & Jacobsen, B. J. (2018). Aflatoxins. In Veterinary toxicology (pp. 983-994). Academic Press.
  28. Wacoo, A. P., Wendiro, D., Vuzi, P. C., & Hawumba, J. F. (2014). Methods for detection of aflatoxins in agricultural food crops. Journal of applied chemistry, 2014(1-15), 706291.
  29. Kowalska, A., Walkiewicz, K., Kozieł, P., & Muc-Wierzgoń, M. (2017). Aflatoxins: characteristics and impact on human health. Postepy higieny i medycyny doswiadczalnej (Online), 71, 315-327.
  30. Solter, P. F., & Beasley, V. R. (2013). Safety assessment including current and emerging issues in toxicologic pathology. Haschek and Rousseaux’s handbook of toxicologic pathology. Academic Press. https://doi. org/10.1016/C2010-1-67850-9.
  31. Bbosa, G. S., Kitya, D., Lubega, A., Ogwal-Okeng, J., Anokbonggo, W. W., & Kyegombe, D. B. (2013). Review of the biological and health effects of aflatoxins on body organs and body systems. Aflatoxins-recent advances and future prospects, 12, 239-265.
  32. Hodgson, E. (2012). Toxins and venoms. Progress in molecular biology and translational science, 112, 373-415.
  33. Food Standards Agency (2021). Mycotoxins.
  34. Winfield, S. (2019). Present day use of solvent extraction in cannabis extraction.
  35. (n.d.). Cannabis Extraction & Solvents.
  36. Clifford, B., Lock, N., Karbowski, R., Johnson, V., Sandy, A., Lugo-Morales, L., ... & Sheehan, C. (2021). Utilizing GC-MS and GC Instrumentation for Residual Solvents in Cannabis and Hemp. In Cannabis Laboratory Fundamentals (pp. 191-222). Springer, Cham.
  37. (2021). What are the risks of residual solvents? Here’s everything you need to know.
  38. PhytoVista Laboratories. (2019). How bad is CBD oil mislabelling in the UK?.
  39. Mahurpawar, M. (2015). Effects of heavy metals on human health. International Journal of Research-Granthaalayah, 3(9SE), 1-7.
  40. Shimizu, F. M., Braunger, M. L., & Riul, A. (2019). Heavy metal/toxins detection using electronic tongues. Chemosensors, 7(3), 36.
  41. Abdul, K. S. M., Jayasinghe, S. S., Chandana, E. P., Jayasumana, C., & De Silva, P. M. C. (2015). Arsenic and human health effects: A review. Environmental toxicology and pharmacology, 40(3), 828-846.
  42. Matta, G., & Gjyli, L. (2016). Mercury, lead and arsenic: impact on environment and human health. J. Chem. Pharm. Sci, 9, 718-725.
  43. Cox-Georgian, D., Ramadoss, N., Dona, C., & Basu, C. (2019). Therapeutic and medicinal uses of terpenes. In Medicinal Plants (pp. 333-359). Springer, Cham.
  44. Hambidge, T. (2021). Government Chemist CBD Food and Cosmetic Ring Trial Final Report Cannabidiol and controlled cannabinoids.


Please note that this article was written by a 3rd-party author who is a specialist on the topic of CBD, hemp and cannabis. Any information or recommendations contained within this article, are independent to the opinion of RUDERALEX® CBD and our employees. We make no claims for any of our products, please read our disclaimer for additional information.