Limitations of Our Drug Checking Service
Our service uses an FTIR (Fourier-Transform Infrared) Spectrometer, which shines an infrared laser at your sample to generate a unique light spectrum. Our technicians then compare this spectrum against a database of over 15,000 substances to identify what’s in your sample. However, there are some limitations that can occur when utilizing this technology for drug checking.
FTIR technology is excellent for high-volume drug checking, but it does have some limitations:
- Identification of substances is limited to what is available in our reference database.
- It has a detection limit of approximately 5%, meaning we cannot detect substances present below that level.
- This includes potent or unexpected compounds that could still pose risks.
- It is less effective for certain types of samples and may not provide full results in every case.
- Results can vary depending on how the sample is mixed or if it is cross-contaminated with other substances.
If multiple substances are detected, the software may estimate approximate percentages. Please note:
- These percentages are estimates only, based on visible ingredients detected by the FTIR spectrometer.
- These estimates help demonstrate the potential distribution of ingredients within the sample.
- However, they do not reflect the actual potency or strength of the substance.
- Potency can vary even between samples with similar contents.
We also use test strips for some substances. While helpful, they have their own limitations for drug checking:
- They do not identify which analog is present (e.g., which fentanyl-type compound).
- They do not show how much of the substance is present.
- They may occasionally give false or invalid results.
If you’re curious about the different drug checking technologies available, we encourage you to explore the BCCSU’s Drug Checking Evidence Summary Report for more information.
FTIR Limitations
Library Database Requirements
The FTIR identifies only substances in our reference libraries, which contain over 15,000 regularly updated entries. Novel or uncommon substances may go undetected. If we can’t find a match, results will show as “no library match” or “uncertain match.”
Should you be looking to test a specific substance, feel free email us at [email protected] to confirm whether it’s in our library. If it isn’t, we may not be able to confirm the active ingredient but can still check for unexpected substances.
5% Detection Threshold
The FTIR has a detection limit of approximately 5%. Substances below this level may not appear in results—even if they are toxic or affect the potency of your sample.
This limitation is especially relevant when testing:
- Pills, blotters, and liquids
- Organic materials (e.g. cannabis)
- Food-based or complex mixtures
Test strips may be used to detect low-dose substances like fentanyl, benzodiazepines, or lysergamides, which the FTIR might miss.
The FTIR cannot accurately test liquids. Liquids and high-moisture samples interfere with analysis, so percentage estimates are not provided for these. Some may still be identifiable—ask a technician if unsure.
If a substance is detected near the limit, we may label the result as an “uncertain match.” When we find no match, we share our best insights based on experience, but can’t guarantee accuracy.
Percentage Estimate Limitations
When possible, we may provide a percentage estimate based on what the FTIR detects. These numbers are generated by software and reflect only the visible components—not the full composition of your sample.
The FTIR cannot isolate individual substances in complex mixtures, so any percentage estimates are approximate. They may not reflect actual potency, and similar-looking samples can yield different results. If a sample is too complex or contains uncertain compounds, the software may not be able to analyze it accurately, and we may not be able to provide a percentage estimate.
When we detect only one substance, we don’t provide a percentage because other ingredients might still be present below the 5% detection limit.
Treat any percentage result as a rough guideline, not a precise measurement.
Sample Mixing and Variability
A sample may not reflect the full composition of a drug. For example, testing part of a pill may not represent the rest. Cross-contamination between samples stored together can also affect results.
To ensure more accurate results, we recommend:
- Submitting well-mixed samples (e.g. crushing the entire pill or crystal and mixing well)
- Keeping different substances stored separately
Test Strip Limitations
We use test strips to detect the presence of three potent substances at very low doses: fentanyl, benzodiazepines, and lysergamides (LSD-like compounds).
These strips were originally designed for urine drug testing—not for checking unregulated substances directly. As a result, there are some important limitations to understand:
They Don’t Identify Which Analog is Present
Test strips can detect a substance or a structurally similar analog, but cannot specify which one.
>For example, fentanyl test strips will show a positive result for both fentanyl and carfentanil—a compound 100–200 times more potent.
We use test strips to help detect substances that may be present below the FTIR’s 5% detection limit, but we cannot confirm exact identity or potency when a result is positive.
They Don’t Show How Much of the Substance is Present
A positive test strip result shows a substance (or analog) is present but doesn’t indicate how much is in the sample.
Because fentanyl test strips can detect as low as 0.001%, a positive result doesn’t mean the substance is present in a harmful amount—but it could be.
If a test strip detects a substance that the FTIR doesn’t, it’s likely present near or below the 5% detection threshold.
Detection Thresholds
The test strips we use have the following approximate detection limits:
Fentanyl: 20ng/mL
Lysergamide: 50ng/mL
Benzodiazepine: 300ng/mL
Risk of False or Invalid Results
Test strips are not foolproof. Results can be influenced by many factors including:
- False positives can occur due to cross-reactivity with similar compounds.
- False negatives can happen when a substance is present in very small amounts, or if the test strip is less sensitive to certain analogs (e.g., 3-methyl fentanyl, carfentanil).
- Some strips may be difficult to interpret, or may not function properly with certain substances. In these cases, we log the result as invalid.
Our technicians use their training to detect and respond to these issues. We repeat tests, use standardized mixing techniques, and draw from our experience with known cross-reactive compounds to provide the most accurate results possible.
Other considerations
Your experience with a drug has many influencing factors. Therefore, if your results do not align with what you experienced, this could be due to something else. We often refer to the 3S’s in harm reduction:
Set
This is what you are bringing to the experience, including your current physical state and mindset. This may include things such as your thoughts, your mood, whether you ate recently or drank enough water, and if you had enough sleep. Your current physical and mental health can vastly affect your experience. – Depending on where your body is at, the drugs you consume could create a different experience despite the same setting and the same substance.
Setting
This is the physical and social environment you are consuming your drugs in. It’s important to consume substances in a supportive environment and with people whom you trust. If you consume substances in an environment where it makes you feel uncomfortable or stressed, it could negatively impact the experience. Make sure to reach out to someone you trust and try not to use alone. – Using in an environment where you feel safe and supported increases your chances of having a positive experience.
Substances
There are several factors directly about your substance that could affect the experience. This may include the dosage you take, the route of consumption, how often you are using the substance, whether it has been cut with unwanted ingredients, and whether you are mixing it with other substances. – Differences in your substances, how much you take, how you take it and how often you’ve been taking a substance can cause different experiences, even when in the same setting.
To check how different substances interact when mixed together, check out the drug combination chart by TripSit.
