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Paper text:
in turkey a kind of smokeless tobacco called 
 maras powder has a lot of addicts in the city of 
 kahramanmara and its surroundings 
 [ 13 ] .
the leaves 
 of nicotina rustica l. are powdered , mixed , crushed with the ash 
 obtained from the oak , walnut tree , or vine stick in the 
 proportion of 1/2 or 1/3 , and humidified a little before it is 
 used .
it is known that the ash blended during the preparation 
 stage of maras powder eases the absorption of nicotine 
 from the mouth mucous membrane by making the medium alkaline . 

maras powder is a kind of smokeless tobacco that is used 
 by the addicts through buccal mucosa instead of cigarette or in 
 order to give up smoking . on the other hand
it is reported that 
 toombak use may play an important role in the etiology of 
 oral squamosus cell carcinoma of the oral cavity and also may be 
 associated with salivary gland cancers [ 4 , 
 5 ] . due to the 
 fact that it is taken orally
, it is reported that the cronic 
 stimulation of the lenfoid tissues in oral mucous membrane may be 
 related to the increased gingivitis , leukoplacis , and oral cancer 
 incidence .
similarly , it is stated that it has a stronger 
 potential of leading to addiction compared to cigarette 
 smoking because of its higher nicotine concentration and prolonged 
 mean usage time .
most of the diseases related to smoking have been 
 known in detail so far .
more than 400 000 people die in the usa 
 because of smoking and the direct expenditures for medical 
 purposes regarding smoking - related morbidity exceed 50 million us 
 dollars .
the effect of smoking on the immune system and its 
 parameters is not understood fully and the data about this is 
 limited and somewhat contradictory .
the studies up till now put 
 forth that the immunotoxic and genotoxic impacts of cigarette 
 arise from the particle phase more than the smoke - phase . the 
 particle phase is composed of thousands of substances , but mainly 
 nicotine .
there are a lot of findings about the fact that nicotine 
 is the major immunosuppressive in cigarette and/or smokeless 
 tobacco .
nicotine causes the secretion of chatecolamines that have 
 suppressive effects on immune system by inducing acth secretion 
 .
it is crucial to clarify 
 the relation between tobacco smoking and immune system in order 
 to understand this biological process fully .
the aim of this study was to determine the effects of 
 maras powder use and cigarette smoking on the parameters 
 of humoral immune response .
the study was conducted between january 2004 and june 2004 in 
 kahramanmaras sutcu imam university , faculty of medicine .
all 
 subjects included in the study population were healthy volunteers 
 recruited from visitors .
the control group was 
 composed of 33 women ( 41.1% ) and 37 men ( 52.9% ) with no 
 history of smoking or maras powder usage ; the smokers 
 group was composed of 31 women ( 42.2% ) and 39 men ( 55.8% ) ; 
 and maras powder group was composed of 17 women 
 ( 45.9% ) and 20 men ( 54.1% ) . the mean ages were 
 37.8  12.5 sd ( standard deviation ) ( min . 19max . 73 ) , 
 37.6  12.0 sd ( min
71 ) , and 41.9  10.2 sd in the control , smoking , and maras powder 
 groups , respectively .
mean ages 
 and the sex distribution of the groups were similar ( p > .05 ) .
selection criteria of the individuals were as follows : cigarette 
 smokers have been smoking a pack of cigarettes ( twenty in number ) , 
 maras powder addicts have been using at least 2 packs of 
 maras powder ( a pack is of 16  3 g sd ) for at least 5 years and nonpassive smoking for control and 
 maras powder users .
the blood samples are collected from each subject by 
 venipuncture of the cubital veins before labour and 
 frozen at 20c after aliquoting their sera 
 until they are studied .
blood samples were analyzed for concentrations 
 of the humoral immune system parameters ( ige , igm , igg , iga , c3 , 
 and c4 ) using nephelometry ( dade behring , marburg gmbh , germany ) . 

the normal values of humoral immune system parameters were 
 accepted as 0.704.00 g / l for iga , 7.016.0
g / l for igm , 0100 iu / ml for ige , 
 0.901.80 g / l for c3 , and 0.100.40
value for ige since its range starts from 0uniu / ml ) , and 
 over these ranges as  high .
 data were expressed as mean values  sd , median and range , or 
 as number of subjects and percentages .
either nonparametric or 
 parametric ( if data was normally distributed ) tests were used for 
 statistical analyses .
anova and kruskal - wallis variance analysis 
 ( followed by post - hoc mann - whitney u test where needed ) were used 
 for comparison of numerical data .
analyses were performed by using spss 
 software , version 9.05 for windows ( spss inc . ,
comparison of humoral immune system parameters in study groups 
 were shown in table 1 .
no statistically significant 
 difference was detected among the parameters except for ige ( p > .05 ) .
ige values of maras powder and smoking groups were 
 significantly higher than that of the control group ( p < .05 ) . furthermore , the distribution of subjects according to ranges of 
 humoral immune system parameters was compared 
 ( table 2 ) . for this purpose
, data was classified as 
 low , normal , and high for each parameter .
the distribution of 
 normal values was similar for each parameter except igm and ige . 
 in control group 1.4% of the subjects had igm values below 
 normal where it was 18.6% and 10.8% in smoking and 
 maras powder groups , respectively ( p < .05 ) .
after chi - square analysis , it was seen that ige values above the normal 
 had been similar in the smoking and maras powder groups 
 and significantly higher compared to the control group ( p < 0.01 ) .
it was stated that using tobacco affects both the cellular and 
 humoral immunity negatively in various ways . nevertheless
, the 
 level of the negative effects could not yet be explained clearly . 
 in a number of studies carried out for finding out the possible 
 effects of cigarette smoke on lymphocytes ,
the relation between cigarette smoking and effects of 
 cigarette smoke on in vitro lymphocyte functions is disputatious . 

some authors reported that there had been significant reductions 
 in the proliferative response of lymphocytes to t cell mitogens . 
 on the other hand
, some others reported that there had been no 
 significant difference in terms of this response between smokers 
 and nonsmokers . besides
, it was stated that these differences 
 might have been influenced by age , sex , dosage , duration of 
 exposure , and ethnic origin [ 815 ] . 

goud et al   reported increases in lymphocyte proliferation 
 and polyclonal igm response caused by smokeless tobacco .
however , 
 lindemann and park   reported that water - soluble smokeless 
 tobacco extract had anticytolytic and antiproliferative effects on 
 peripheral lymphocytes .
, it was shown that 
 cigarette smoking was closely related to a series of immunological 
 deteriorations accompanied by decreases in immunoglobulin levels , 
 the number and the functions of nk ( natural killer ) cells , and the 
 number of t cell subgroups [ 9 , 
 11 , 12 , 
 14 ] .
moszczynski et al 
  had observed a decrease of 
 cd4/cd8 ratio due to the decrease in the serum concentration of lysozyme and 
 immunoglobulins and a decrease in the number of ( cd 16 ) nk 
 cells particularly in the addicts who had smoked for more than 10 
 years and an increase in the number of ( cd 8) cytotoxic t 
 lymphocytes .
it was shown that smoking decreases serum levels of 
 almost all types of immunoglobulins except ige ( ige increases ) 
 [ 1820 ] .
there are also some articles that defend the 
 idea that it has no particular effect on immunoglobulin levels . in our study ,
rates of subjects with a serum igm level below 
 normal were significantly higher in smoking and  
 maras powder groups than in control group ( p < .05 ) .
however , the 
 differences of serum igm levels between the 3 groups were not 
 statistically significant . this may be interpreted as 
 contradictory .
when the data was studied carefully , it 
 was seen that the igm values below normal were very close to the 
 lower limit . as for ige levels ,
rates of subjects with values 
 above normal were significantly higher in smoking and 
 maras powder groups than in control group ( p < 0.01 ) .
nearly all of the individuals ( 86.5%95.7% ) 
 have levels of iga , igg , c3 , and c4 within the normal limits . in some studies
it was reported that alcaloid , 
 nitrosamine , and nicotine contents distinguish between nicotiana 
 rustica l. and nicotina tobacum l. alcaloid content of 
 maras powder ( nicotiana rustica l. ) may be 610 times 
 more than that of nicotina tobacum l. . 

it was reported that tobacco - specific nitrosamine content of toombak 
 was one hundred times more than that 
 of other types of smokeless tobacco used in sweden and usa , and 
 toombak use was described as the highest nonoccupational 
 carcinogen exposure documented [ 4 , 
 5 ] .
three times more 
 urinary cotinine levels were found in maras powder 
 addicts than in smokers .
however , lindemann et al reported that plasma nicotine levels were found to be similar in 
 smokeless tobacco users and smokers .
nevertheless , in 
 our study , the effect of maras powder on humoral immune 
 response was found to be similar to that of smoking .
as noted earlier in our study , many of the researchers stated that 
 smoking affects the immune system and its parameters negatively at 
 various levels .
nonetheless , the level of this negative effect 
 could not be determined yet effectively and evidently .
we 
 believe that further studies investigating the effects of 
 different types of tobacco usage on humoral immune system 
 parameters are needed .
distribution of the humoral immune system parameters 
          with respect to low , normal , and high ranges in study groups . * statistical analysis could not be performed due to the limited number of cases . *
background . 
 the aim of this study is to assess the 
 impacts of  maras powder  and cigarette 
 smoking on the parameters of the humoral immune system . 
 material and 
 methods . 
 one hundred seventy seven subjects were included in the 
 study . 
 the iga , igg , igm , c3 and c4 levels were detected via 
 nephelometric method . results . in 1.4% of the control 
 
 group igm levels were below normal where it was 10.8% and 18.6% 
 in maras powder group and in cigarette smoking group respectively . 
 
 the igm levels of both groups were significantly lower compared to 
 the control group ( p < .05 ) . 
 nonetheless , the ige levels of 
 maras powder group and smoking group were found to be remarkably 
 higher compared to the control group ( p < .01 ) . 
 conclusion . 
 effects of maras powder on humoral 
 immune response were found to be similar to that of smoking .