Eleven terpenes, four data states: why temperature tables are not comparable

Does the number set on the vaporizer indicate the temperature of the dried flower?

No. The display shows the temperature of the heating element or the air entering the chamber, not the temperature of the raw material itself. The plant material absorbs heat unevenly, and the airflow during inhalation takes away some of that heat. There is certainly a difference between these two quantities, although no one has publicly measured it.

This difference is the first of two reasons why the temperature table for terpenes does not translate to what happens in the device's chamber. The number in the table describes the behavior of a pure substance in a laboratory vessel, while the number on the display describes the state of the heater, and between the two lies plant material with its own uneven temperature. Even if the table were flawless, its column and the display would still describe two different measurement objects.

A separate text of this cluster breaks down this difference into factors and shows why the vaporizer setting does not equal the temperature of the dried flower. Here, one statement suffices: no one has published a measurement indicating how much cooler the material is during a typical inhalation compared to the setting. In documents reaching patients and their caregivers, the authors of the review comparing their own measurements with the literature found directly false data, alongside interchangeable use of three concepts: boiling, vaporization, and evaporation (PMID:35442765).

Does the terpene start to evaporate only after reaching the boiling point?

No. Molecules escape from the surface of the liquid at any temperature where that liquid has any vapor pressure, which is practically always. Boiling only means that the vapor pressure has caught up with the surrounding pressure, and there is no switch at that moment. The entire idea of targeting a single terpene is based on this misunderstanding.

For this page, the consistency of this statement for the tables themselves matters. Since volatilization has no threshold, the column with boiling points is not a list of activation thresholds, but a list of values describing one narrowly defined physical situation. Which component escapes faster is determined by comparing vapor pressures at the same temperature, not by whether any number from the table has been exceeded.

Losses begin long before the device's chamber, already during the drying and curing of the material, and increase during decarboxylation, with the monoterpene fraction depleting the fastest (PMID:35442765). The physics of vaporization is broken down separately. tekst tego klastra. Hence, one thing is needed here: the number in the table describes the condition of equilibrium, not an event that can be triggered by turning a knob.

Why do two temperature tables for terpenes provide different numbers?

Because the eleven terpenes in this project have four different data states in the public PubChem database, not one. Six have a boiling point given along with pressure, one has only a measurement under reduced pressure, two have just the number without any pressure, and two have no boiling point at all.

We conducted the check ourselves, with one query to the public database interface for terpenes. The ones with pressure given alongside the number are caryophyllene, limonene, linalool, myrcene, pinene, and terpinolene. Without specified pressure are nerolidol and ocimene. Neither bisabolol nor farnesene has a record with a boiling point: for both, the database responds with a message that such a position does not exist.

These four states do not differ in certainty, only in the type of information. The number without pressure is not a worse measurement of the same quantity. It simply does not indicate under what conditions it was obtained, so it cannot be compared with the number given at 760 millimeters of mercury. Comparing them in one column creates an order that is not present in the data.

This is also evident from the number of records themselves. Out of eleven terpenes, the database holds twenty-four source records from six different reference sets, and the explicit pressure carries ten of them. Fourteen records, which is the majority, do not indicate at what pressure they were obtained. A table constructed by taking the first available record from each terpene is therefore more likely to hit a value without conditions than a value with conditions.

Where does the number close to one hundred degrees come from in the tables for humulene?

From the only record that the database has for it. PubChem states for humulene 99 to 100 degrees Celsius, but the measurement was taken at a pressure of three millimeters of mercury, over two hundred fifty times lower than atmospheric pressure. The database does not record any other value for this terpene.

Pressure shifts the boiling point by dozens of degrees and this is not a second-order correction. This is shown by caryophyllene, as the same position has two records in the database at once: 256.0 to 259.0 degrees at 760 millimeters of mercury and 264 to 266 degrees Fahrenheit at 14 millimeters of mercury, which is about 130 degrees Celsius. There is a difference of 127.5 degrees between the two numbers, and both describe the same substance.

The consequence for the table is arithmetic, not interpretative. A value from almost vacuum inserted into the column next to atmospheric values shifts humulene about 57 degrees below the lowest of them, meaning it should be read as the first evaporating component. Meanwhile, humulene and caryophyllene are isomers with the same molecular weight, and caryophyllene ranks highest in that column. Such a number is not a rounding or simplification, but a record of conditions that are no longer visible in the table.

Do the records in one database agree with each other?

Not always. The same terpene may be described by several records from different reference sets, and these provide values that differ by several degrees. For linalool, the extreme records are separated by six degrees, for terpinolene four. This is small compared to the difference resulting from pressure, but enough for two tables to appear contradictory.

Additionally, there is the conversion of units. Six out of twenty-four records are given in degrees Fahrenheit, and converting to Celsius gives a value with a decimal part, which usually disappears in tables due to rounding. The same position may also be given twice, once in each scale, so counting records without checking their content can lead to taking one measurement as two independent ones.

None of these records is incorrect in its source. The error only arises when transcribing, when removing pressure, units, and range, and leaving just the number. The same review of documentation for patients found boiling temperatures simply stated incorrectly (PMID:35442765). The same authors also rejected the label "full spectrum" as misleading, since the composition of no product replicates the composition of the plant from which the product was derived.

What does this mean for a person who has a prescription for dried flower?

That the temperature table is not the basis for anything related to one's own treatment. Dried hemp is a pharmaceutical raw material dispensed by a doctor's prescription in the Rpw category, so the method of administration is determined by the attending physician, not by a set of numbers circulating online without a source.

This page does not provide any temperature as one that must be introduced, and has no such intention. It describes the state of records in a public chemical database and what cannot be derived from these records. There is also no mention of equipment, as the selection of the device and method of taking the medication is a conversation with the attending physician, not the content of an informational article.

An additional matter is that temperature comparisons mainly revolve around products from general sales. category of dried flower includes flowers of industrial hemp available without a prescription and is a different type of product than the dried flower dispensed in pharmacies, although both may be described by the same table. We maintain a list of pharmaceutical strains to which this cluster pertains in the comparison of currently available strains.

What has not been studied in humans regarding the vaporization of terpenes from dried flower?

The most important link is how much terpene from heated dried flower actually reaches the lungs and the bloodstream. The evidence base of this page has two positions: a review with our own composition measurements and a laboratory measurement. Neither of them studies humans, so the chain from the number in the table to the effect on the patient breaks off along the way.

The second of these studies is a laboratory measurement. Five monoterpenes were heated within the range that vaporizers operate, after which the volatile products were chromatographically separated following thermal desorption and identified by mass spectrometry (PMID:35773373). The percentage of the starting compound that emerged from heating intact reached between 97 and 98 percent for the most resilient position, while for the weakest it dropped to a range of 11 to 28 percent. The denominator here is the amount introduced into the measurement, not the share in the strain profile.

The greatest resilience was shown by myrcene, the least by terpinolene, and the distance between the extreme positions is nearly ninefold. Among the decomposition products, molecules with masses of 134, 150, and 152 were recognized, one of which is likely fenchol. What inhaling such products does to a person has not been studied; however, what is widely described is something else, as oxidized oils from this group can cause allergies and irritation.

Hence the conclusion that the tables do not convey. Even a correct record regarding pressure and units speaks of the behavior of pure substance in a laboratory vessel, not of what reaches the vapor and what survives unchanged along the way.

Frequently Asked Questions

Does the boiling point of a terpene indicate at what temperature it will evaporate from the dried flower?

No. The boiling point is the temperature at which the vapor pressure equals the surrounding pressure. Evaporation also occurs below this value, and its rate gradually increases, without a threshold for activation.

Why do the tables provide a number close to one hundred degrees for humulene?

Because it is the only record that the public database has for this terpene, and it comes from a measurement at a pressure of three millimeters of mercury. When transcribed without pressure, it goes into the column with atmospheric values, where it means something else.

What does the record 3 mm Hg at the boiling point mean?

That the measurement was taken at a pressure about two hundred fifty times lower than atmospheric pressure. Under such conditions, the substance boils significantly below the value it has in the air at ground level.

Is it known how much terpene from heated dried flower reaches the bloodstream?

No study has been published that would measure in humans how much terpene from heated dried flower actually reaches the lungs and the blood. It is known in what order components evaporate and what portion decomposes along the way, but it is unknown how much of this reaches the body or whether it has any measurable effect. It has also not been shown that setting the vaporizer to the temperature listed in the table as the boiling point of a specific terpene leads to inhaling that particular terpene.

Where do the numbers in the table on this page come from?

From the public interface of the PubChem database, one query per terpene, along with the pressure record and the name of the reference set. The records were cited in the form they stand in the database, without standardizing the units.

Does this page provide a temperature for vaporization?

No. Dried hemp is dispensed by prescription from a doctor, and the method of administration is determined by the attending physician. The text describes the state of records in the chemical database, not the method of taking the medication.

The material is informational and does not replace medical advice. Dried hemp is a pharmaceutical raw material dispensed by prescription from a doctor in the Rpw category. Editorial text from the editorial team of ubucha.pl.