Document aJmYkXwYa5q716xXLQDp2GrJR

Transfer of M etallic C onstituents of C ig a r e tte s t o th e Main Stream Smoke E v e r e tt C. C o g b ill, Marcus E. Hobbs, Duke U n iv e rs ity Tobacco Science, ifey 10, 1957 When to b acco i s burned most o f th e m e ta llic c o n te n t rem ains in th e ash a lth o u g h sm all q u a n t i t i e s p a s s i n t o th e main stre am smoke and become in c lu d e d in th e p a r t i c u l a t e p h a se . The p re se n c e o f m e ta ls in th e smoke nay be due to (1) v a p o r iz a tio n o f m e ta llic compounds - c h i e f l y , t h e i r c h lo r id e s , o r ( 2) due t o m echanical e n tra in m e n t o f n& crofragm ents of ash o r tobacco, or due to b o th . In o rd e r to determ ine which mechanism i s th e major fa c to r , q u a n tita tiv e d ata on th e tr a n s f e r o f v ario u s elem ents were o b ta in e d . I f th e m etal p a s s e s i n t o th e smoke b y m echanical e n t r a i n ment, then the re la tiv e p ro p o rtio n of th a t m etal to th e o th er m etals in th e smoke sh o u ld be n e a r ly e q u a l t o i t s r e l a t i v e p r o p o r tio n i n th e to b acco . I f , on th e o th e r hand, th e tr a n s f e r o f th e m etal occurs a s a r e s u l t of vaporization, of i t s chloride fo r in stan ce, then th e re la tiv e propor t i o n o f th e m etal in smoke w i l l v a ry .from t h a t i n to b a cc o depending on the degree of i t s v o la tility - i . e , d ifferen ces in th e tra n sfe r e ffic ie n cie s of the in d iv id u a l elem ents w ill depend on the d iffere n c e s of the v o la tility o f t h e i r m e ta llic compounds. ' Methods: .. . C ig a r e t te s t e s t e d were th o s e o f f iv e p o p u la r dom estic b ra n d s , 70 mm in le n g th and w ith o u t f i l t e r s and were p u rc h a se d i n th e summer o f 1956. B efore smoking, th e c i g a r e t t e s were c o n d itio n e d and w eighed. Con d i t io n in g was accom plished by p la c in g them i n 58$ r e l a t i v e h u m id ity i n a h y g ro sta t over d e liq u e sc e n t sodium bromide w ith a r e s u ltin g m oisture co n ten t of 18.1$ (measured as lo s s in w eight a t 110 C f o r 20 h o u rs). ' 2. Cig a re t t e s from one c a r to n o f each b ran d were w eighed and p la c e d i n groups matched in w eig h t b y .0 5 gram. The h ig h e s t and lo w e st w eight c a te g o rie s 're r e j e c t e d . . The a u to m a tic smoking a p p a r a tu s , lo a n e d by L ig g e tt and % e r s Tobacco *j>., vas d e sig n e d f o r 15 c i g a r e t t e s , and i n succession 0 .2 second p u ff s 're tak en e v e ry 60 seco n d s. Only 13 c i g a r e t t e s w ere u sed le a v in g 2 spaces fr e e to check p u ff volume which was about 35 ml. Ten p u ffs were tak en ;n each c i g a r e t t e le a v in g a b u t t le n g th o f 2.0 t o 2.5 cm. Three sam ples o f smoke were c o lle c te d . ;. : #1 from 117 c ig a r e tte s Brand A #2 130 "B ' #3 " 15 6 " o f each o f f iv e stan d ard b ran d s, o r a t o t a l o f 780 c ig a r e tte s 'J''-_'Tpba;CCo'.s?fi%>les-were 'ta k e n ; from : .. . . "1 ~ e q u iv a le n t o f c i g a r e t t e s in c lu d in g p a p e r o f Brand A 42 _ n ;t ii it it it it B :.r`3 - 11 " " five brands noted. " . n each of ^; - T ie smoke was condensed i n a s e r ie s - o f c o ld t r a p s . The f i r s t s e r i e s ? rs th re e c y l i n d r i c a l f l a s k s , 9 x 28 cm ., W ith a volume o f 1. 7 l i t e r s asch, followed by th ree s p ira l tra p s a l l connected w ith ground g lass j o i n t s and immersed in c o o lin g b a th s . The f i r s t f l a s k was in ic e a t about 0C, th e o th e r fiv e were in d ry - ic e ---alco h o l b a th s w ith a tem perature a t - ?2C. The f l a s k s were w eighed b e fo re and a f t e r smoke c o lle c tio n s b room te m p e ra tu re . :,j - The c o ld tr a p s were fo llo w e d by two f l a s k s packed w ith g la s s wool having approxim ate volumes of 500 ml and 125 ml re s p e c tiv e ly . These were weighed b e fo re and a f t e r smoke c o l l e c t i o n to d eterm in e th e amount o f f i l t e r - ioLe smoke e sc a p in g th e c o ld t r a p s . k Jf 0004494 L S r ***'= ' . ' : . , . : \ ... 3 . ; About k% o f th e t o t a l w e ig h t o f smoke c o lle c te d was in t h i s f i r s t f la s k and a b o u t ,0' . 1$ 'in ' th e second , i t w as assum ed. , 'th e n., t h at a b o u. t 96$ Xo f th e .. . . . V . t o t a l smoke was c o lle c te d in th e c o ld t r a p s , and t h i s i s th e smoke t h a t was a n aly zed . About 87$ o f th e t o t a l w eight was in th e th re e c y lin d r ic a l flasks, ' : The smoke t o be a n aly z e d was wabhed from th e tr a p s by a l t e r n a t e r i n s in g w ith r e d i s t i l l e d a c e to n e , O.OoNN h y d ro c h lo ric a c id in 90$ a c e to n e , and w a te r, No m ention i s made in th e a r t i c l e c o n c e rn in g th e number o f . i mes th e t r a p s a re washed o r by what means - i t i s d eterm in ed t h a t th e smoke has been c o m p le te ly removed. A f te r rem oval o f th e smoke, th e tr a p s were r in s e d w ith lOOsc o f c o n c e n tra te d n i t r i c a c id which was saved and used l a t e r f o r d ig e s tio n o f th e to b a c c o . The smoke s o lu tio n was concen- t r a t d by e v a p o ra tio n u n t i l th e a c e to n e was removed. The a v erag e w eig h t o f smoke o b ta in e d was 7It mg p e r p u f f o r 7U mg p e r c i g a r e t t e . The c o n tr o l to b a cc o sample was ta k e n a s follows: f o r each 13 c i g a r e t t e s i r~oked in sample No. 1 and No. 2 one c i g a r e t t e o f th e same w eig h t group . vas re se rv e d f o r th e tobacco .sample. Thus, fo r sample #1 th e re were nine 1 groups o f 13 c i g a r e t t e s smoked and th e r e f o r e n in e c i g a r e t t e s mixed to g e th e r fo r th e tobacco sam ple. I n sample #2 th e s e were te n groups and th e r e f o r e ten c ig a r e tte s in th e tobacco sam ple. In each sample the c ig a r e tte s were rill mixed to g e th e r and the e q u iv a le n t o f fo u r c ig a r e tte s used f o r each sam ple. The sample f o r No. 3 was composed o f one a v erag e c i g a r e t t e o f ,33 each o f th e f i v e b ra n d s .u s e d . .Digestion o f th e o rg a n ic m a tte r i n th e smoke and to b a cc o was begun w ith d ilu te n itr ic acid . 0004495 Successive evaporations a f te r ad d itio n s of concentrated n itr ic acid were th en done u n t i l th e samples were liq u if ie d . This obviously a p p lie s t o th e to b a cc o sam ple, s in c e th e smoke was a lr e a d y i n s o lu tio n . No men- iio n i s made o f th e end p o in t f o r th e d ig e s tio n o f o rg a n ic m a tte r from th e smoke sam ple. The s o lu tio n s were th e n t r e a t e d w ith e q u al volumes o f w a te r, c o n c e n tra te d n i t r i c a c id , and 12% p e r c h lo r ic a c id , and th e n ev ap o rated . This was re p e a te d u n t i l c o lo rle s s o r l i g h t yellow s o lu tio n s re s u lte d , a t which tim e the so lu tio n s were evaporated to n ear dryness. Hot d ilu te hydrochloric a cid was then added to th e re sid u e , the p r e c i p i t a t e d s i l i c a was f i l t e r e d o f f and th e r e s u l t i n g s o lu tio n s made up to a d e f in ite volume (which was n o t s ta te d ) . The r e s u l t i n g s o lu tio n s were a n a ly z e d b y e s ta b lis h e d p h o to m e tric p ro c e d u re s . Na+ and Kr were d e term in e d b y flam e p h o to m etry u s in g th e P e rk in - Elm er Model j2~C . ^ead was i s o l a t e d and m easured c o lo r im e tr ic a lly by e x tra c tio n w ith d ith izo n e. A rsenic w as separated as a rsin e and d e te r mined by th e molybdenum b lu e c o lo rim e tric te c h n iq u e . .ement Sample No. X1 . 2' - Na ,, 1 2 Pb 1 2 3 As :-. ;' 1 2 : " ' 3 ' Micrograms p e r C ig a re tte R elativ e Tobacco Smoke % T ra n s fe r 26800 27100 13h 0.50 138 o .3 l 870 9 .2 1.06 890 7 .1 0.80 21 1.0 h.B 8h 3 .3 3 .9 h i 1 .9 h.6 7.1 26. h 13.2 0.31 l.h 0. 0h6 h.h 3.3 3.3 O ther m etals analyzed were calcium , magnesium, aluminum, iro n , man- gaese, copper, z in c , n ic k e l, chromium. From th e wide range o f t r a n s f e r e f f i c i e n c i e s found i t was s t a t e d t h a t v a p o riz a tio n was alm ost com pletely re sp o n sib le fo r th e m e ta llic m a te ria l found in smoke. M echanical en train m en t alo n e was thought to account only f o r calcium , magnesium and aluminum in th e smoke. To e x p la in t h i s p ro c e s s o f v a p o r iz a tio n , i t was p o in te d o u t i n th e discu ssio n th a t the tem perature in the burning cone of a c ig a re tte i s from 830 t o 920C. Some m e ta ls w ith low b o i l i n g p o in ts such a s a r s e n i c , le a d , and z in c may undergo v a p o r iz a tio n i n th e m e ta llic s t a t e , -^t was f e l t t h a t o th e r m e ta ls were tr a n s p o r te d a s c h lo r id e s . I t i s known t h a t th e a lk a l i m etal c h lo rid e s a re v o la tile a t tem perature below th e ir b o ilin g p o in ts which i s ll&3C fo r sodium c h lo rid e , l550C f o r potassium c h lo rid e and 950C f o r le a d c h lo r id e , -^ead c h lo rid e v a p o riz e s r a p i d l y above 35"0C and the c h lo rid e and oxide o f tr i v a le n t a rs e n ic vap o rise below 700C. The a u th o rs s t a t e t h a t th e y f e l t t h a t th e m ajo r p a r t o f th e a r s e n ic and le a d found i n th e smoke was from th e in s e c tic id e a p p lie d t o th e to b acco p l a n t . The a r s e n ic - le a d r a t i o i n th e c i g a r e t t e i s c o n p a ra b le t o t h a t i n the lead arsenate in se c tic id e . . Sample No. P b /cig . (ug) As c ig . (ug) R atio As/Pb 1 ? 3. 21 - ' 7 .1 8h 2 6 .k la 13.2 T h e o re tic a l r a t i o Pb H As 0^ ( i n s e c t i c i d e ) ' ' : ' O .31 0.31 0.32 0132 0.36 I t was concluded th a t th e t o t a l q u a n tity o f m e ta llic elem ents in th e smoke o f one c i g a r e t t e was 130 m icro gram s, o f w hich about 9Q% was p o ta ssiu m and 5% was sodium and a b o u t 1.5% le a d . T his work was su p p o rte d in p a r t by g r a n ts from Damon Runyon Memorial Fluid. 1 / . .