if heroin was legal it would be extremely more harmful than alcohol,how many people do you know that tried alcohol and became alcoholics....fuck all!! maybe one out of a thousand,now think of how many people you know who tried heroin and became addicts.....enough said eireann 1 most of you guys 0.
Addiction isn't the be all, end all of damage caused by drugs. Putting aside the argument about which is more addictive, and to what extent, in a clean, legal environment, alcohol addiction is many times more damaging to the body than heroin addiction.
Alcohol, just off the top of my head, causes liver damage, increases blood pressure and causes damage to the cardiovascular system, is a neurotoxin and a well known carcinogen with alcoholics experiencing much higher rates of certain cancers. These aren't problems caused by administration, or adulterates, these problems are inseparable from the use of the drug. And that's completely ignoring the peripheral issues associated with alcohol abuse and addiction, drunk driving, violence, and the like. Someone with a severe alcohol addiction almost certainly
will eventually die of that addiction if they don't stop drinking.
Heroin, on the other hand, is almost completely benign when administered in measured doses using a sterile procedure. Someone could inject heroin every day for the rest of their life and it wouldn't reduce their lifespan as long as they're careful in measuring doses and administer it in a clean and hygienic fashion. The worst it does mess with your hormone levels, inconvenient, but nothing compared to the list above.
The risks we commonly associate with heroin use (overdose, infection, blood-borne diseases, toxic contaminants) all stem directly from the prohibition of the drug. Overdoses happen because street heroin is of varying purity, fatal overdose on pure opiates during recreational use is relatively rare unless they're combined with other CNS depressants (if you look at the numbers, I think you'll find that the majority of 'opiate overdoses' involve at least one other depressant, usually alcohol or benzodiazepines).The rest are all a result of users being forced to use dirty, contaminated product in unsterilized conditions, which is a direct result of heroin prohibition.