I don't trust these studies but I am sure some of you might be intrested. I found this study in
Shisha Health Test
The smoke was developed by using shisha with a large tobacco head.
This answers to a nicotine quantity of 2 medium strong cigarettes (e.g. Marlboro)
approximately 2 mg nicotine. For the rest still approximately 95% steam were measured.
This smoke is not possible to compare with cigarettes, cigars and other smoke Articles.
With shisha we don't talk about smoke, we talk about steam this is because of the humidity of tobacco. When tobacco is dry there is less smoke.
Because there is a large water content the smoke will bind with all kinds of "foreign molecules"
these cannot be measured with conventional methods.
For this reason we use an optical tool "a filter" to examine how many tar is produced with an shisha.
The picture shows the filters after smoking.
Left the filter of the water pipe with large tobacco head with apple tobacco and metal filter
Right the filter of the cigarette ultra i.e. a light cigarette (nicotine 0.1 mg, tar 1 mg).
The tests were carried out on several types of shisha and with several types of tobacco. These reproduction where not clear.
The numbers are in the pallet of the normal deviations.
The quantity water used had little influence for its disadvantageous character , however, the role of the separation between tobacco and coal was important.
The next list shows the tar level (the metal filter was approved as 100%)
directly presenting of the coal
The role of water and the column here is also again speculated concerning the role of water and the calculations:
The contents of the nicotine of 8g a "tobacco charge"
40.0 mg nicotine
the contents of with the passage column/the hose
2.20 mg nicotine
the contents of in water
3.50 mg nicotine
But where the rest of 34.3 mg is a question sign. In the column!?
The "filter impact" larger than water is the column. For this reason there is a brown sauce when cleaning the shisha. But even as important is changing the water regularly. It also shows that the water changes to green after 3 smoke sessions.