Report Prepared for: Scientific Inhalations
Topic of Study: McFinn’s Triple-Filtered Waterpipe
1. Goal of the project
Scientific Inhalations has developed a unique inhalation device designed to provide an improved experience for its users over alternative devices. The device, named McFinn’s Triple-Filtered Waterpipe, consists of a glass bubbler and has two chambers containing different filter materials. The first chamber is filled with activated virgin coconut carbon and connected between the bowl and the water trap. The second filter contains organic cotton and is connected between the inhalation device and the mouth piece.
The goal of this study was to investigate the effectiveness of the filters in removing harmful contaminants purported to be present in smoke vapor. This is performed by comparing filtered smoke vapor with unfiltered smoke vapor and comparing them for their presence of possible harmful chemicals.
2. Material and methods
A laboratory setup was constructed in which the mouthpiece of the smoking device was fixed to tubing leading to a cold trap containing an organic solvent at low temperature. Inhalations were simulated using a vacuum pump and timed valve. The settings were made such as to represent the smoking behaviour of a typical adult person.
The material used for this study was a single batch of medical cannabis, which was tested in triplicate producing the following results for cannabinoids:
In The Werc Shop’s experience, this may be considered an average result and is relatively representative of other typical medical cannabis strains present in California.
The influence of the filters was investigated by using the smoking device as described in the accompanying instructions (see appendix 1), while comparing this data to the same setup without filter materials present. In both cases, water was present in the inhalation device. The experiment was repeated three times without filters and three times with filters. In each experiment a total of 1200 mg (+- 20 mg) of dried plant material was smoked within three sessions of 400 mg each. The plant material used was moderately peeled apart with multiple smaller pieces included in each cycle. The material was not blended nor ground to a powder, provided this would not accurately represent the burning behavior of plant material in a real life situation typical to a medical cannabis patient’s use. The large amount of sample (1200 mg) used in each experiment is considered to be sufficient enough to negate variability within the plant material in each experimental sample. Between experiments, all glassware, including the inhalation device, was cleaned with acetone and water. When filter material was used, the material was replaced with fresh filter material following each experiment.
Samples were collected and analyzed with GC-FID. Gas chromatography was selected in order to sensitively identify a large breadth of volatile chemicals known to be present in smoke vapors. For identification, mass spectra were recorded using GC-MS. Tentative identification was performed by a search of the mass-spectral
data against the National Institute of Standards (NIST) mass-spectral library of known chemical entities to provide a tentative identification. Any subsequent confirmation of the components was performed using a known commercially available reference standard.
3. Results of GC-FID
Figure 1 below shows a comparison of the collected smoke produced by the inhalation device with and without filters. A clear influence of the filters producing a definitive difference in the chromatogram was observed.
Figure 2 below shows a close-up of the chromatograms demonstrating the results of the three replicate experiments with filters and the three replicate experiments without filters. The experiments appear very reproducible and a clear influence of the presence of filter material is observed.
To confirm the observations of above, the filters were removed from their housing and the trapped components were extracted following the experiment. The chromatograms of the unfiltered and filtered smoke are shown, as well as the chromatograms of the extracted filters. This data clearly shows that the “missing” compounds in the filtered smoke were trapped in the filters, and not lost in the analysis.
Figure 1. Collected smoke with and without filters present
Figure 2. Expanded collected smoke with and without filters present
Figure 3. Chromatograms of extracted filters
4. Results of GC-MS
The following compounds were found to be matched from the NIST mass-spectral
library and were either fully or partially removed by the inhalation device when the
filters were used:
Naphtalene was purchased and a reference standard was prepared and measured
on both GC-FID and GC-MS. Both retention times and MS spectra matched a peak
that was strongly reduced when using the filters.
Figure 4. Overlay of chromatograms of filtered smoke, unfiltered smoke and naphthalene reference standard.
A reference standard for pyrocatechol was also acquired and measured on both GCFID and GC-MS. The analytical results confirmed the reduction of this compound when filters were used. An overlay of the sample chromatograms containing pyrocatechol are showing in Figure 5
Figure 5. Overlay of chromatograms of filtered smoke, unfiltered smoke and pyrocatechol reference standard.
5. Conclusions and Remarks
This study shows that the McFinn Triple-Filtered Waterpipe inhalation device does filter out and remove, either fully or partially, multiple potentially harmful components from medical cannabis smoke vapor. At least two of the components that have been found and indentified, naphthalene and pyrocatechol, are listed under California’s
Proposition 65 as cancer causing agents.
Further studies of the device intend to identify additional harmful components which are removed by the filtering system. Special attention will be given to known carcinogens. Quantification of various chemicals found will be attempted in order to determine the relative performance of the filtration system.