what about all these solvents and chemicals SWIY has been using and exposed to? Or the car pollution, or agrotoxic in the food, GM food, hidrogenated fat, cellphone radiation (even if you dont own one yourself), artificial light at night, electromagnetic radiations of all sorts, fluorine in toothpaste, chemicals of shampoo, etc etc?
there's risks and benefits in all things. each one has to measure what they think they feel is good for them.
Your quite extreme argument of "then take whatever man made thing and lets see what happens with your grandgrandchildren" is quite unreasonable for SWIM. He is vegetarian and has very good eating habits, doesnt take even caffeine or alcohol (only entheogens and lsd), healthy and always doing things and being physically active, being balanced with family, friends and wife, studying, consuming consciously, planting trees and trying to improve himself while helping the world. He thinks he has his bases covered pretty well and is trying to leave the best contribution to the world and demonstrating his gratitude for existance as possible. SWIM sees his body as sacred and respects it very much.
So having this in mind and having researched with multi-sided information, SWIM thinks LSD is safe for him. Its his own decision that hurts nobody else. He does this with full conscience of his actions. Theres no evidence of genetic damage with lsd so SWIM sees no reason to suppose damage of the 5th generation. Millions of people have consumed lsd, lived and had normal kids and died, and maybe their kids already had kids that are also normal. If you dont want to take it, its fine, but please dont post as if you're preaching on SWIM (if you're not, then sorry for misunderstanding)
As for the whole discussion of natural and unnatural, everything is owned by mother earth, or life, so it is all 'natural'. The distinction is between things that are out of the harmony, we could say, and things that are harmonious with the underlying unity or pattern. Like a cancer cell, it is still part of the body, excepts it 'forgets' it and starts reproducing and growing unharmoniously. Stuff humans make can 'blend' in with all of creation, or be highly dissonant. We see in different cultures, certain temples, artifacts, art forms and so on that fit with this category, which demonstrates a certain level of conscience of the one who made it.
Also, as it has been said, there are natural things that are very toxic and dangerous, even natural drugs that also have been used for thousands of years. For example tobacco. It has been smoked (and chewed and ingested and snuffed) for thousands of years, is maybe THE most disseminated drug in the amazon, and yet, we all know the dangers of tobacco smoke. Also datura of all kinds are very important to many natives. I know Im steering as far away from datura as possible, it doesnt matter how long or by who its been used. I trust my consciousness, not if somebody uses or not. I read the information available and decide, trying to indeed have all the next generations in mind.