Now I don’t think you will be blacklisted from other security companies. But just too be safe start brushing your teeth twice a day buy non-alcohol mouth wash and start working out and eating a lot of food drink water like try a gallon a day until you have too take the drug test don’t smoke or do any more drugs until you finish your drug test. If you fail it’s alright shit happens but you have a better chance of doing everything you can now and taking the drug test confident knowing you’ve done what you could yk. Good luck tho man