Tell your son that if he stays away from units that draw air from the 510 connections he will not have a problem. Whether it’s fumes, or more so some type of corrosion, don’t know but when a tank draws air from the 510 then that area must be cleaned daily before use. Otherwise you start tasting metal.
Notice on the Blue Tank and the little air hole just above the threads of the 510. If any type of fumes are given off then this would be the way it is inhaled. No other way. So, it just goes to say a good unit will be safer than the cheaper units on the market.
I had a diatribe to go with this pic, but I think the pic says it all.
Ok…mini diatribe:
People need to do solid research on anything they’ve seen or heard to make sure the story or statement is true, before they rebroadcast it to the masses. There’s a lot of bullshit and hate that gets spread around via social media and person to person. Too often people just accept everything they read and hear as truth and spread the misinformation and lies.
My nephew started going on about it again a few days ago. Funny thing happened, my sister has a blood pressure meter and had just measured her blood pressure. Her diastolic pressure was 68, it has gone down since she started vaping. He asked if he could check his and his diastolic pressure was 95. Pretty high for a guy of 38! She told him he better go and see his doctor and that maybe vaping was not such a bad idea after all.
I was a hold out for a long time myself; just didn’t want to give up my favorite habit! But, with time, perhaps he’ll see that neither you or his Mom are “suffering” from vaping and join the believers! One can hope!
Here’s another one, don’t you dare touch my RYO! I still haven’t given up my favourite habit, it has just become a healthier one. Ironically it was my sister that got me into vaping and then she went back to cigarettes, now I’ve been the one to turn her back to vaping again. I made her a shitload of juice, she only wants tobacco so that’s nice and easy for me. Apparently it’s in the genes. She loves the Cohiba, fortunately for her (and me) I’ve got a large bottle of that.
All it takes is a try on a decent ecig and a convert is born, we’ll get him eventually
Perhaps he’s a candidate for a NET? I know it means frequent wick changes, but maybe if he got set up with a single coil dripper to futz with at home in the evenings, over time he’d get the knack of it.
I’m vaping some of my straight Virginia NETs in a dripper right now and it takes me to my happy place …partaking of smoking RYO. He’d forget about all the nonsense talk of “fuming batteries” if he could taste a good NET.
One can hope!
She loves the Cohiba, fortunately for her (and me) I’ve got a large bottle of that. 
…partaking of smoking RYO. He’d forget about all the nonsense talk of “fuming batteries” if he could taste a good NET.