Unfortunately, marijuana is classified by the FDA as a schedule one drug, and therefore, little research has been done on it. Even so, we do have some reliable information about it's effects.
You should know that marijuana contains more than one type of THC as well as various other cannabinoids and other chemicals. Further, by smoking it, there are effects on the lung tissue itself (though some people make a substance known as "cannabutter" and cook with it instead). Since, however, you focused on justTHC, the best information available is actually based on an FDA approved drug called Marinol. It is a synthetic form of THC (in fact, those taking the prescription will often test positive for marijuana usage when taking a urinalysis for illegal drugs).
Rather than providing a lengthy answer to both, I've provided 2 links below in the Sources and Related Links Section; one addresses the side effects of Marinol (THC usage); the other addresses the effects of marijuana usage on the body.
HC stands for High Cube
No, you get to keep all your hc furni.
HC on an ultrasound means Head Circumference.
You can only buy HC furniture in habbo if you join the Habbo Club (HC). Joining HC costs around 30 coins per month, and will give you one free HC item per month. If you are not HC, you can still have the furniture, but you can not buy it from the catalogue.
Normally, HC gas is Hydrocarbon.
HC Sibir was created in 1962.
HC Bloemendaal was created in 1895.
HC Rotterdam was created in 1925.
Bergischer HC was created in 2006.
HC-One was created in 2011.
HC Milano ended in 1956.
HC Milano was created in 1924.