JWH-18 is a synthetic cannabinoid with similar subjective effects to those of THC, active principle of marihuana. These last years this substance has become very popular and, as a consequence, the carcinogenic properties of this molecule have been widely discussed.
In this text I will talk about the potential carcinogenicity of JWH-18.
JWH-18 (Fig.1) contains naphthalene in its structure (coloured in red). When we introduce naphthalene in our organism, it is going to pass through various metabolic processes. On some of them, the carcinogenic structures known as epoxides (Fig.2) are going to be produced, which are able to interact with DNA and proteins. As the naphthalene in JWH-18 has no other functional groups attached to it, it is very prone to produce epoxides. Technically speaking, an epoxide is the structure made by two carbon atoms and one oxygen, joined together by simple bonds in a triangular disposition.
As we introduce JWH-18 in our organism, it’s metabolism starts. We will focus on the metabolism of the naphthalene part of the molecule, as it is the one responsible of the carcinogenic properties.
On the first stages of the process, the cytochrome P450 breaks the double C=C bond to a simple C-C bond. Then both carbon atoms join to the same oxygen, creating an epoxide. Some of the epoxides made are later transformed to alcohols or other non-dangerous functional groups. Unfortunately, not all the epoxides can be converted, and they will remain in the body interacting with DNA and proteins, which is the cause of their carcinogenicity.
The following diagram shows a scheme of the described process (Fig.3).
Taking this information in account, we could consider JWH-18 to have carcinogenic properties, but to what point? It’s true that ingesting naphthalene is not going to be good for your organism, but before pointing a substance as a complete carcinogenic, we must first take in account some considerations. One of them is that we are daily exposed to naphthalene, which is floating in the atmosphere. It is calculated that in our houses there is an average of 2,2ug of naphthalene for every m3 of air (which is equal to 0,0004 ppm). The tobacco smoke of one cigarette (without filter) has 422ug of naphthalene in total.
Lets now see how much naphthalene we are consuming in an average dose (2,5mg) of JWH-18:
The molecular weight of JWH-18 is 342g/mole, so in 2,5mg of JWH-18 we have 7,31x10^(-6) moles.As 1 mole has 6,022x10^(23) molecules, 7,31x10^(-6) moles corresponds to 4,4x10^(18) molecules of JWH-18. As each molecule of JWH-18 has one naphthalene, we have a total of 4,4x10^(18) naphthalene molecules in 2,5mg of JWH-18. As the molecular weight of naphthalene is 128g/mole (-1H) = 127g/mole, 4,4x10^(18) naphthalene molecules weigh 9,3x10^(-4) g, which is 930ug of naphthalene.
One dose of 2,5mg of JWH-18 has 930ug of naphthalene.
(We could also have calculated this taking in account the relationship between the molecular weight of the JWH-18 and the one of naphthalene. Seeing that the naphthalene corresponds to the 37% of the total weight of the molecule, 37% of 2,5mg is 930ug. The same result obtained by two different methods shows that the calculations are correct.)
As we can see, the quantity of naphthalene ingested when consuming an average dose of JWH-18 is similar to the naphthalene we would introduce in the body when smoking two cigarettes without filter. Taking this information in account, and without being completely sure if the naphthalene from the JWH-18 would produce the same quantity of epoxides as free naphthalene, the only thing left is to think if this extra ingestion of naphthalene from JWH-18 is worth the risk.
Knowing all this, the users which decide to consume this substance will be able to follow a risk reduction policy more efficiently, really knowing what kind of risks are being taken.
*Please leave your thoughts about all this, as it is just theory and speculation.*