My friend was very nervous when he noticed that I'm performing electrolysis in a room that we've just been residing. (it was under open window to let $\ce{H2}$ out) After a sharp argument, he made me shut it down, though I still thought that it was safe.
I'm using $\ce{Na2CO3}$ as electrolyte and as far as I know, it doesn't get electrolysed. I use normal pipe water. Such water surely contains some minerals however in really small amount. My friend pointed out that it also contains chlorine and that's what he's afraid of. He would disregard my notice that he's drinking this water often.
I'm using copper electrodes, producing copper hydroxide and copper carbonate. I failed to find out whether these compounds are hazardous. They're in solid state anyway.
From what I've said you can see that I'm very sure that the reaction is not hazardous. But I'm not chemist. There could be something I didn't think of in which case I've been poisoning myself for quite a while.
Could you make me sure or warn me?