Everyone is different. Alot of factors come in to play. Such as weight,metabolism, how often and how much used, and how active you are. Could be as little as three days up to eleven days. Give yourself two weeks to play it safe....each day counts .....and drink that water.
Immediately in blood. Within 5 minutes in urine.
24-72 hours at the most.
Too long. Please tell whoever is concerned that they need to stop doing it. Not because the law says so, but because it's killing them.
3days
3-5 days
Marijuana is detectable in the urine for a month after consumption.
3-5 days
40 days
Cocaine is detectable in urine as soon as 4 hours after first usage
Heroin lasts in the system [detectable by a urine test] for around 3 days approx, but of course, those are the metabolites, the heroin itself will not be felt after a few hours, as the liver breaks it down...but the pesky metabolites are what catch you out if you have a drugs test. Allow 5 days to be fully sure.
Benzodiazepines can be detected up to a week after use.
If you mean would bleach remove heroin from a urine sample the short answer is no heroin is a drug not a bacteria or virus if bleach was added to urine it would definitely not take the heroin out of the urine if it were present.