Hello, I know selenium toners are toxic, but how much toxic? I first ordered, and then withdraw from order selenium toner because I don't have well ventilated darkroom. That is, there is one ventilator, but I am not sure how efficient it is. There is one option, that is when spring (end of winter) come I will selenium tone my prints on my balcony, but till then... Oh, by the way, is there any problems when selenium toning old prints, that is, is there some limit from time of making prints till time of selenium toning that print. Thank you.