You can mention all the non-peer-reviewed studies you want, but they are not conclusive of anything, see 'cold Fusion for details.
More: 'Marijuana damages DNA at least as much as tobacco and may have a link to lung cancer, according to a study of mothers and their new born infants.
Researchers in America have found that blood from marijauna smokers has nearly three times as many DNA mutations as that of non-smokers.
Marijauna smoke contains many of the carcinogenic chemicals found in cigarette smoke, but, unlike tobacco, has never been linked to the kinds of genetic mutations associated with lung cancer.
But Dr Marinel Ammenheuser and her colleagues at the University of Texas Medical Branch now have evidence that marijauna smoking causes the same kind of damage to DNA as tobacco.
Damaged cells
Dr Ammenheuser said her group studied a group of pregnant women who were marijauna smokers, but who did not use other drugs, and did not smoke tobacco.
She said: "We did a test to detect changes in a particular gene in the DNA in their white blood cells, and found that the marijuana smokers had three times as many DNA damaged cells as the non-smokers.
"We did the same test on the blood cells for the umbilical cords of the new-borns of some of the marijuana smokers. These infants likewise had three times as many damaged cells as those of non-smokers."'
and
'WASHINGTON (CNN)-- In the first study of its kind, researchers found that smokers of marijuana and crack cocaine show the same kinds of precancerous conditions caused by smoking tobacco.
The findings were released Tuesday in the Journal of the National Cancer Institute.
In the study, researchers examined samples of respiratory tract tissue from participants who ranged in age from 21 to 50. To be eligible, the participants had to be in one or more of the following categories: Marijuana smokers who smoked an average of 10 or more marijuana cigarettes a week for the last five years or longer; crack cocaine smokers who smoked one gram or more of crack cocaine a week for nine months or longer within the past year; or tobacco smokers who smoked 20 cigarettes or more a day for the last five years.
The researchers looked at genetic markers known to be associated with increased risk of lung cancer. Changes or overproduction of some markers were found in a majority of the study participants.
The findings suggested that tobacco was not the only smoked substance that set the changes preceding lung cancer development in motion.
The study also showed that habitual smoking of tobacco, marijuana or crack cocaine in combination could potentially lead to more cancerous alterations in the molecular makeup of cellular structure than single-smoking alone. '
and from the NIH:
'Effects on the Heart
One study has indicated that an abuser's risk of heart attack more than quadruples in the first hour after smoking marijuana7. The researchers suggest that such an effect might occur from marijuana's effects on blood pressure and heart rate and reduced oxygen-carrying capacity of blood.
Effects on the Lungs
A study of 450 individuals found that people who smoke marijuana frequently but do not smoke tobacco have more health problems and miss more days of work than nonsmokers8. Many of the extra sick days among the marijuana smokers in the study were for respiratory illnesses.
Someone who smokes marijuana regularly may have many of the same respiratory problems that tobacco smokers do, such as daily cough and phlegm production, more frequent acute chest illness, a heightened risk of lung infections, and a greater tendency to obstructed airways 9. Smoking marijuana possibly increases the likelihood of developing cancer of the head or neck. A study comparing 173 cancer patients and 176 healthy individuals produced evidence that marijuana smoking doubled or tripled the risk of these cancers 10...
Other Health Effects
Some of marijuana's adverse health effects may occur because THC impairs the immune system's ability to fight disease. In laboratory experiments that exposed animal and human cells to THC or other marijuana ingredients, the normal disease-preventing reactions of many of the key types of immune cells were inhibited14. In other studies, mice exposed to THC or related substances were more likely than unexposed mice to develop bacterial infections and tumors15,16.'
More from NIH/NIDA:
'A study of 450 individuals found that people who smoke marijuana frequently but do not smoke tobacco have more health problems and miss more days of work than nonsmokers do.39 Many of the extra sick days used by the marijuana smokers in the study were for respiratory illnesses....
Marijuana users who have taken high doses of the drug may experience acute toxic psychosis, which includes hallucinations, delusions, and depersonalization - a loss of the sense of personal identity, or self-recognition.10,15 ..
# Increases risk of chronic cough, bronchitis, and emphysema'
A cursory viewing of studies and links at the NIH will give you the above info and more.
Again, I'm all for legalization, so I really don't care if you believe the NIH or not. Your assertions about the safety of marijuana are laughable, however.
