Actually, I believe the article you sourced has an error in it.

The cigarettes-only group had a higher rate of emphysema than the combination smokers did, according to the abstract from the journal Thorax.
http://thorax.bmj.com/cgi/content/abstract/thx.2006.077081v1

I think that's correct, because I remember reading this somewhere else a few months back, and thinking it showed that pot possibly provided some protection against emphysema. Although, it isn't very statistically significant.

I guess all the stoners can now "breathe easy". Actually, I can tell from personal experience that pot is way better (and possibly better for a person's health in general) than tobacco. I smoke pot everyday (several times a day, okay like 20 times) and can still manage to run three miles pretty easy, every other day. I couldn't even breathe standing still if I smoked one cig (chronic bronchitis from wet cigarettes as a youth). I know everyone is different but I would say go green.

Who owns YOUR lungs?

Suggestion....now that it is known ,that smoke is harmful to breathing, big tobacco industry must inform the public to eat their ciggies.Nicotine is a drug...with a specially designed delivery system.

Many marijuana users don't smoke a whole joint.... they pass it around, which makes it even less bad.

If it were bad for the lungs, who cares? Use brownies instead. Less is lost to smoke in the air anyway :-)

Conclusive evidence shows that marijuana does not cause lung cancer at all

Donald Tashkin, the author of the study you site doesn't seem to agree that the evidence is conclusive. This is from an interview in High Times:

http://www.hightimes.com/ht/news/content.php?bid=1390&aid=22

I don’t consider this to be a definitive study; there are a lot of limitations in this study. One is that there was a higher rate of refusal among the cases, so there could have been a selection bias. And the other is that the recall of marijuana use could have been erroneous. The patients may have reported that they used more than they really did or less than they really did and that over and under reporting could have differed between different cases and controls and that could have affected the results. So it’s not a conclusive study, but it is, I think, an important study because the fact that it was designed as well as we could to minimize the biases and we failed to find a positive association.

And a little later on:

Well, I think that people who have smoked marijuana a lot and are worried about cancer development might or probably will feel some relief that there is some evidence not supporting that link but I still feel that the heavy smoker might be at risk.

(Emphasis mine.)

It seems that there is some evidence that suggests that smoking pot might cause lung cancer (precancerous changes in the lungs) and other evidence that it might not (absence of lung cancer in the study).

Scott again:

hardly any marijuana users actually smoke enough to hurt their lung

Tashkin again:

We found that smoking marijuana regularly was associated with an increased frequency of cough and sputum on most days. So these marijuana smokers often had chronic bronchitis, about twenty percent of them, compared to about twenty-five percent of tobacco only smokers. They also had an increased frequency of acute chest cold, defined as an increase in cough and sputum that lasts a certain number of days. They also reported more wheezing than non-marijuana smokers. So there’s definitely some impact on respiratory symptoms. When we biopsied the airways, the tissue lining, widespread evidence of injury. Very similar to the damage that we saw in tobacco smokers. I don’t want to use technical terms, but the cells that normally line the airways have a certain shape and they have cilia. The purpose of the cilia is to move mucus up from the lung into the mouth in order to cleanse the lung of mucus it’s produced and we found that the cilia cells were often lost and replaced by non-cilia cells, or sometimes the cells will form patterns that we call ‘squeamish,’ it looks like skin. These are changes in the appearance of the nuclei. These are changes that have been found to be precancerous. They are changes that in tobacco smokers preceded the subsequent development of lung cancer.

The subjects of this study smoked on average about three joints a day. That's more than the average pot smoker, I'll bet, but not so rare that you'd classify them as "hardly any."

Perhaps Dr. Tashkin is part of the anti-marijuana propaganda machine, turning out wildly exaggerated scare stories. But you were the one to hold him up as an authority in the first place.

rachelrachel

According to the National Survey on Drug Use and Health - "Current smokers aged 12 or older smoked on average 13 cigarettes per day on the days they smoked."

Were I able to smoke high quality pot whenever I wanted, I'd probably average .5 "pot cigarettes" a day.

Which means that the pot I'd smoke would need to be approximately 26 times as harmful as tobacco.

Tobacco is a New World plant. Marijuana is an Old World plant. It’s possible humans coevolved with cannabis in the Old World in a way that not only created a tolerance for marijuana, but may have become a symbiotic arrangement in preserving health by protecting human neuron cells.

There are chemical tolerance problems among indigenous populations, such as with Native Americans and alcohol, for example, compared to Northern Europeans and their ultra-tolerances to alcohol; no doubt the European ancestors swam in the stuff. Jews often have a low tolerance for alcohol and consequently a low rate of alcohol addiction. Eastern Mediterranean types have lactose intolerance in addition to alcohol intolerance, while pastoral Western Europeans who survived on dairy products don’t show lactose intolerance.

Human tolerance of cannabis would seem to indicate that our species has been exposed to the mighty herb for a very, very long time; longer than dairy products, and certainly longer than tobacco. It’s no wonder 400,000 people die every year from tobacco. Humans might evolve a tolerance for tobacco over the next 2500 years, but at the moment, tobacco smoke may be one of the worst things that could go into human lungs.

Our bodies seem tuned to the plant world in subtle and strange ways. Morphine is a ubiquitous and miniscule constituent of all plant derived food substances, such as milk. That’s right, all you mommies out there who eat green, leafy salads. But not to worry. The chemical cocktail appears necessary.

Our bodies have receptor sites specifically for morphine as well as cannabinoids. Salvia Divinorum affects beta-opioid receptors. Before Salvia, I didn’t even know we had beta-opioid receptors. But they’re far out.

Finally, I want to talk about Moses and the burning bush. Why a bush? And why burn it?

The whole story of Moses makes no sense whatsoever unless there’s something really special about that bush. Maybe Moses burned a lot of bush. He was alone; so nobody saw what he did with the bush. What other bush burns and talks to you at the same time?

Giordano

The ONDCP is starting a gradual,helpful program for the upcoming approval of SATIVEX. It's all about delivery systems.The ONDCP knows about the positive medical info available on cannabis, and will modify it's stand to an anti SMOKE campaign. How else would GW Pharma be able to announce an expected US approval date for it's product, of 2011? A little bird in a bush told me this is true. REDGREEN

Smoke is bad for lungs.

Vaporize. The benefits are amazing.

Look it up.

www.vaporbrothers.com

hey marijuana is actually good for you> It can decrease the nicotine habit. Marijuana is not an addictive drug.

HEY BABE!!! LOL

SERIOUSLY GIRL YYOU NEED TO STOP!!!!!!!!

Ok so weed is the greatest ever. Omg the GREATEST. tHE OTHER COMMENT I POSTED BECAUSE IT WAS NAUGHTY. so im gonna use good person launguage when I say god dammit weed is not bad It fing rules yo!11 I mean fo real who carews about like all the bad things think of thta delish smell and that great feeling? I could be cheezy and say I have been diagnosed with cancer and I smoke weed every da to relieve my pian, but I wont because that would be a lie. I smoke weed because it rules.

yoooo

[size=9057]Why buy weed when anime is free...[/size]

I THINK THAT WEED IS AWESOME AND I LOVE IT BUT I THINKS CIGARETTES ARE GROSS AND REALLY BAD FOR YOU BUT ACCORDING TO THIS WEB SITE 1 JOINT IS EQUAL TO 5 CIGARETTES

1 joint is as bad as 5 cigs da fuck!!!