"I Want To Try Weed"- Horrors in Teen Parenting

“I want to try marijuana some day.” Words, I fear, may come out of my teen son someday.
Hating the idea of being unprepared, I’ve given my response some thought. And, well maybe, some research as well.
It is clear to me that with the advent of many States legalizing the sale and use of cannabis for recreational purposes, the conversation around ‘pot’ is becoming more relevant and mainstream. It feels now somewhat akin to discussing the usage of alcohol with teens. I decided having a prepared defense for my parental ‘DON’T’ would be in my best interest.
So, what would I say? And, more importantly what would I not say?
First off, I will not tell him NOT to use marijuana. Guided by the emotional and reactive amygdala, my teen is risk and pleasure seeking. Prone to defiance, If I tell him NO that would surely lead to finding a bong under his bed within the week. I have decided to approach the topic using a two-pronged argument.  
To begin with, I will remind him that his adolescent brain is rapidly changing; increasing connections between the brain cells to eventually generate more effective brain pathways. His brain is basically a work in progress. You don’t throw some random ingredient into a cake mix. Nor do you forget to measure the baking soda lest you get a solid brick instead of a fluffy slice of cake. All of his ‘make the best brain possible’ ingredients are already pre-measured and at the ready. This is not the time to be introducing random drugs nor alcohol as research has proven that exposing the brain during the teen years can alter or delay these developments.
Studies have shown that teenagers are more likely to become addicted to alcohol and drugs [source: Hotz]. In that developing prefrontal cortex, synapses are selected based on whether they’re used or not, so behaviors that shape the brain are more likely to be maintained if started at this age. The brain is acting a bit like a sponge; it can soak up new information and change to make room for it, a concept known as plasticity.
I have always found my son willing to accept information based on scientific evidence. I’m counting on this conversation to be no different.  If I have enough supporting data to persuade him to wait, I will feel victorious. Important to me as well, is how to keep him from potentially hurting himself with tainted weed.
Although, lacing marijuana is uncommon; it can happen. Dealers might add cocaine, LSD, or meth to their product. It is also not unheard of to find crushed glass in the mix – a trick to make the weed sparkle with the appearance of more trichomes (those little tiny crystal-like hairs that cover the buds, hold all the good stuff). The different methods of hashmaking focus on isolating these sticky little parts of the cannabis plant because they house the majority of its resin.
I will suggest to him that when he and his brain are more developed that sourcing it from a regulated dispensary, in a State that had legalized marijuana, would be safer. Let’s hope this addition to the argument will fly as well.
Will I meet my parental goal? I don’t know. I may never know. He may never confide in me or ask me but, I have to be ok with the idea that I did my best. I know I will not prevent my teen from engaging in pleasure seeking risky behavior. Nor, do I really want to. It’s essential to growing up and separating. For now, I will keep my fingers crossed that he will continue to make healthy, good decisions. And, hopeful that if the topic does come up for discussion, that I won’t choke and forget my well thought out argument. Does it ever get easier?