Document 6538392

Transcription

Document 6538392

Date : April 2, 1996
To : Ms . DINAH MYERS
Quality Assurance
Fm : GUY SPENCE
Scientific & Regulatory Affairs
MICROANALYSIS OF CONSUMER COMPLAINT SAMPLE
95-148 : DIANE BUOTE, PHILADELPHIA, PA, MORE F120 MENTHOL,
"CIGARETTE EXPLODED"
OBJECTIVE
Ms Buote claimed that when she smoked "1 - 2 cigarettes close to the filter, they 'kinda
exploded"' . Examine the returned materials to determine whether any evidence existed that
would support her allegation .
SUMMARY
The materials received for microanalysis consisted of a pack containing six unlighted
cigarettes, a butt, and a note to which three small particles had been taped . The blend of the
whole cigarettes was examined through the stereomicroscope at 12X . Absolutely nothing
resembling explosive or incendiary materials was discovered in them .
The butt had no tears or rips which might suggest that an explosion had occurred in it .
Analysis of some of the loose blend particles in the pack revealed two laminae specimens which
were littered with bright metallic-looking particles . These were prepared and analyzed with the
SEm/Enx system . That analysis revealed that they were Mg particles, a very potent incendiary
metal when in a finely divided state . It now strongly appears that the cigarette was tampered
with by the insertion of incendiary materials rather deep within the rod .
EXPERIMENTAL
The materials submitted for microanalysis consisted of six unlighted cigarettes, one butt,
and a note to which some small particles had been taped . The note read, "I Sh'lpk this was part of
what exploded--it stuck to my arm ."
The material taped to the note was examined through the stereomicroscope . These
~
.~i
specimens included a somewhat circular black particle which measured approximately one w
millimeter . This particle was attached to an SEM stub with double-sticky carbon adhesive for
.i
microanalysis . The untaped side was oriented upward . Also under the tape, there were three ro
http://legacy.library.ucsf.edu/tid/zgg11d00/pdf
w
To : Ms .
DINAH
MYERS
Fm : GUY SPENCE
smaller orange-amber colored particles . Two of these were likewise attached to the SEM stub for
microanalysis . They were similarly oriented on the stub .
Preliminary analysis of the butt revealed that it was 39 mm tip-to-tip . It had no tears or
rips that would strongly suggest that an explosion had occttrred . The char line was not evenly
burned around the rod . The cigarette had been burned to within 3%x mm of the face of the filter
plug on one side, but the opposing side had burned to within one mm of the plug . On
examination of the charred tip components, including the paper, I observed a light-colored
residue on two laminae particles and one stem particle . Although my impression of this
substance was that it was paper ash, I prepared the two laminae particles for electron
microanalysis .
A . INSTRUMENTS, OPERATING CONDITIONS
The samples were plated with an ultrathin layer of evaporated carbon prior to their being
analyzed with the instruments . The instruments employed for this microanalysis were the
AmaaY 1910 FE SEM/Luvtc Isis Eux ANALYZER. For the microanalysis the electron gun was
adjusted to 10kV accelerating potential, and the beam was controlled with a 300 µm final
aperture and a condenser lens setting of-20 on the panel . All images were acquired with the
solid state Backscattered Electron (B86) detector, which detector produced a signal intensity that
is directly proportional to the average molecular weight of the target substrate . In order to focus
the EDx (specimen characteristic X-Ray) signal to the EDx detector, the specimen stub was tilted
350 toward the detector and placed at a vertical distance of 15 .5 mm below the focal lens of the
gun . Selected images were archived on disk, and selected spectra were quantitatively analyzed
by computer employing standards generated from a C . M . Taylor Standard block .
RESULTS AND DISCUSSION
The blend from the six whole cigarettes was examined through the stereomicroscope .
The analysis was an effort to discover some anomalous material(s) that might be either explosive
or incendiary . None of these materials was found . Thus, these unlighted cigarettes were judged
normal .
When the prepared materials were imaged with the S6M, it became immediately clear that
one of the two laminae specimens was significantly littered with several particles that were
nontobacco . That lamina specimen, which I labeled "#1" on the photomicrographs, had several
of these foreign particles, but one was quite large compared to the others . An overview of that
particular lamina and the debris that was collected on its surface is shown in FIGURE 1 . From the
SEm image acquired at 20oX, the brighter particles reveal their average molecular weight with
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To : Ms. DINAH MYERS
Fm: GUY SPENCE
respect to the tobacco lamina was higherl by an appreciable factor . The graphics box that was
drawn around the large particle was a computer measuring system that indicated particle
dimensions of 136 µm x 117 µm2 .
FIGURE 2 shows a view of the large metallic-looking particle recorded at 750X with the
Stavt . In that particular image, the particle appeared to consist of a compressed ball of material,
much of which seemed to be thin platelets . It was, without doubt, not a firmly solid ball of
homogeneous material . Another feature that was revealed in this image was that although the
material was heavier than tobacco, it also had a few smaller contaminating particles on it . They
were revealed by the small white spots seen on its surface .
Ftol :Viewoflaminakl,from20oXSrntimage . Brightpanicleson FtG2 :Viewoflargestpanice nlamina,seenlnFw2. Viewfmm
surface are nontobacco .
75oX
5eM
image . Particle dimensions shown in label .
FIGuRE 3 exhibits a further enhancement of the large particle . It was taken from the SEM
image collected at 2 .5kX . There, the extend to which the particle was composed of layers of
smaller, often platelet-type materials became clearer . Also, the bright particles, previously seen
' The Bss signal is generated by high energy electrons that are essentially gun electrons that bounce off the surface
of their target substrate, with little loss of energy . The heavier the average molecular weight of a specific substrate,
the more efficient becomes its ability to effect this "electron bounce" . Thus, when two neighboring target areas
consist of different substrate materials, the heavier substrate produces a brighter signal because it more efficiently
redirects the incident electron beam back to the Bsa detector than does the lighter substrate .
2 In reality, the height measurement was too short, for the 35° tilt caused shortening of the true value . I suspect that
the reading was more like the 136 µm horizontal value recorded .
Page 3
To : Ms .
DINAH
MYERS
Fm: GUY SPENCE
in FicuitE 2, were seen to be angular crystals . At this location and magnification, an EDX
spectrum was collected and quantitatively analyzed . It revealed that the material was a blend of
components, with the major components being Ca, Mg, K, Cl, and S . Of course, oxygen was
also a major constituent . The results of the quantitative analysis are disclosed in TABLE 1 . Some
significant impressions were immediately made when these results were seen . First, much of the
data resembled that which would be collected on residue from a firecracker explosion . The
exception would be in the constituent Ca, which certainly came from the paper filler . Second,
the materials present in this spectrum certainly did not come from a traditional cigarette load
detonation. That material is always pure lead, from the reduction of explosive PbN6 .
.TA@LB_1 : Quantitative Spectral Analysis from Area
Shown in F76uaE 3 .
Spectrum label : I30umPartMgKCalmag007Map 1
Elmt Element Atomic Compound Nos . of
% % % ions
Mg K 10 .80 11 .39 MgO 17 .90 0.24
Si K
0 .58
P K 1 .45
S K 3 .74
Cl K 2 .41
K K 20 .69
1 .24
j .
r n an: • i~ .
flc 3 : V iew of surface structure of particle shown in Fla 2 . View
from 2 .5kX Seet image . Note that the brighter particles on the
sW clure indicate that they were of different composition than
the basic substructure . They were crystalline whereas the
substructure appeared to be compressed platelets .
0 .01
1 .20 P205
3 .31
0.02
2 .99 S03
9 .33
0.06
1 .74
0 .00
0 .04
13 .57 K20
Ca K 29 .22 18 .70 Ca0
31 .12 49 .89
0
Total 100 .00 100 .00 97 .59
ur .." J~r .lll_I
' le~m --
0 .53 Si02
24 .92 0,28
40 .89 0.39
1 .03
Anion sum 1 .07
• = Q Sigma
In order to get information about the arrangement of discreet components in the structure
seen in FtGu1tE 3, elemental E D x maps3 were collected over the same area . Figures 4 and 5 show
various window combinations of the EDx map from F1GuRE 3 . FIGuRE 4 shows the BSE image
and maps for elements Mg, Cl, and K . FIGuRE 5 shows a variant of the map where the upper left
quadrant represented a combined map structure of the three elements, S, Cl, and K . By analyzing
these map data, it was determined that K, Cl, and S had spatial arrangements that indicated Cl
was pure KCI (or perhaps KC1O3, which map structure would be identical), and that S existed in
identical space as K, indicating that it was probably K2SO4 . There was no mixing of Mg with
' The generation of an EDX map is accomplished when the beam rasters across the field, producing bright signals
(from the charasteristic X-rays) for each element window when that element is detected . Simultaneously, the system
produces an SEM image window along with the selected element maps .
Page 4
Fm : GUY SPENCE
any of the above three elements . If it had reacted in an exothermic reaction, then it was probably
in the form of its oxide .
FtG 4 : Fox of area shown in FIO 3, from 2 .5kX SeM image. The maps FtG 5 : Another view of the EpX map, this time showing the S
show spatial locations of Mg, Cl, and K . Note that laaer two component . The upper left quadrant shows atombination of
elements indicate that the crystals are KCI (or KCIO,) . the three elements : S, Cl, and K. Produced in color, it revealed
that S was coincident with K (probably KiSUJ . Not shown,
combined maps revcaled no mixing of Mg and S .
'
In FIGURE 1, shown previously, there was a flake located just above and slightly toward
the right of the measurement box . The flake was evaluated at high magnification, both by image
and chemistry . FlcuaE 6 shows that flake, from the 2 .5kX SEM image . The line across its body
is a computer measurement line, revealing that it was 38 .5 µm in length, which was
approximately the length of the flake . The flake was analyzed by Evx. The quantitative analysis
of its spectrum, shown in TABLE 2, disclosed that it was 12% Mg (or 20% MgO) . The spectrum
also contained an appreciable amount of S, which is a sensitizer to incendiary fuels . Other
ingredients that suggested that the material was a residue from an incendiary reaction was Cl and
K, which are key ingredients of the oxidizing agent of choice, KClO4 (or occasionally KC103) .
Finally, it also contained P . The reference literature suggests that phosphorus sesquisulf de
(P4S) is a key ingredient in match incendiary blends .
Page 5
TABLE 2 : Quantitative Spectral Analysis from Area
Shown In FIGURE 6.
Spectrum label : k2Flake on IaminalMgKSCICaP
Elmt Element Atomic Compound Nos . of
% % % ions
Mg K 12 .08 12 .84 MgO 20 .03 0.26
Si K
0 .55
0 .51 Si02
1 .18
0.01
P K
1 .36
1 .14 P205
3 .13
0.02
S K
4 .97
4 .00 S03
CI K
3 .97
2 .89
12 .41
0 .00
K K 39.65 26 .20 K20
Ca K 8 .24 5 .31 CaO
0
29.18 47 .11
b 3I1 .'.
. .`.ini .
ym
!
Iq .N AY IN
r~llll
.m .
4l .
FtG 6 : View of Mg-rich flake located on tobacco lamina M a . From the
2 .5kX SEM Image. See EDX quantitative analysis date in
TABLE 2 at right .
0.08
0 .06
47 .76 0 .52
11 .53
0 .11
0.94
Total 100 .00 100 .00 96 .03
Mion sun 1 .00
. .Q Sigma
Again referring back to F1GURE 1, there was a rather sizable contaminant particle shown
to the left and slightly above the horizontal center of the measurement box . That area was
analyzed at higher magnification . The particle's morphology is shown in F1GUttE 7, which is a
view of the SEM image acquired at 2 .5kX. From the various shades of brightness, it was obvious
that more than a single element phase was present in the structure . An Enx map was acquired
over the area. Those data are shown in FIGUaE 8 . In the map, the Mg spatial distribution was
coincident with the bright branched material from the image, horizontally center downward .
From its appearance in
7, the material looked as if it had been deposited in a molten state'
in a splatter, and cooled in that configuration. Although the original map collection acquired five
elements (Mg, Cl, S, K, Ca) and the BSE image, no more than four of these specific
FIGURE
elements/image can be copied for insertion into this document at once . Therefore, FIGURE 9
displays another selection of elements from this map group . In it, the identity of the small
aggregated group of particles above the Mg deposit was seen to be Ca . Of course, the specific
identity was CaCO3, for the particles resemble very strongly those crystals frequently seen in
analysis of cigarette paper.
The Enx spectrum from that area was analyzed quantitatively . Those data are shown in
TABLE 3 . It shows that a significant amount of the materials included incendiary ingredients Mg,
Cl, P, S, and K .
TABLE 3 : Quantitative Spectral Analysis from Area
Shown in FICURE 7 .
Spectrum label: A30nIam/1 l 2 .5kXOnMgCaKSplash
Elmt Element Atomic
Compound Nos . of
% % a/o ions
Mg K 5 .89 6 .23 MgO 9 .77 0 .14
Si K
2 .SON~ W_N kV "t", i', r~ .n
; x:
: MA
J :- :LNiu
Fto 7 : View of mass of a contaminant on lamina R I . View of the
2.5kX Seht image . sec EDx maps in Fta 8 .
0.54
0 .50 5i02
1 .16 0 .01
P K 2 .25 1 .87 P205
5 .16 0 .04
S K 6 .34 5 .08 S03
15.83 0 .11
CI K 3 .45 2 .50
0 .00 0 .05
K K 22 .23 14 .62 K20
26.78
0 .32
Ca K 27 .06 17 .36 CaO
37 .86
0.38
0
32 .24 51 .83
1 .13
Total 100 .00 100 .00
96 .55
Anion sum
1 .19
• ~ Q Sigma
In the SEM analysis of the prepared materials, a second lamina section was found having a
significant amount of incendiary-type components on it . Its surface was considerably different in
appearance from that of lamina#1 . Rather than an array of discreet particles, relatively few in
number, this lamina#2 was well covered with contaminant materials . Much of it was discovered
by EDx analysis to be CaCO3 (from the paper ash), but in the contaminant blend, the EDx spectra
showed a rather significant amount of incendiary-type materials similar to that which was
identified in the discreet particles on lamina#1, previously reported . A view of lamina#2 is
exhibited in F1ouItE 10, which was taken from the 250X SEM image . An EDX spectral analysis
of this area produced quantitative data shown in TABLE 4 .
Fto 8 : ImagelFDx map array showing spatial arrangemenlof eiemenis FLO9 : Eox map array ofeiements rmm F1o 7. Note that Ca was
Mg, S, and CI . Note that bright, larger materials toward bottom coincident in space with the aggregate of small erystais situated
of image were principally Mg deposits, above the Mg branched material .
Fm : GUY SPENCE
TABLE ¢ : Quantitative Spectral Analysis from Area
Shown In FtoUnE 10 .
Spectrum label : SpecLaminaq2NoLgPart Wi MgEtc
Elmt Element Atomic
Compound Nos . of
%
%
%
ions
Mg K 3 .85 4 .20 MgO
6 .39 0.09
Si K 0.99 0 .93 Si02
2,11
0.02
P K 1 .63 1 .39 P205
3 .74
0.03
S K 3 .62 2.99 503
9 .03
0 .06
CI K 2 .44 1 .83
0.00
0 .04
K K 15 .52 10 .51 K20
18 .70
0 .22
Ca K 41 .16 27 .20 CaO
57 .59
0 .58
0 30 .79 50.96
1 .08
Total 100 .00 100,00
97.56
FIG 10 : View or250X SEM image, IaminaN2 .
Anion sum 1 .12
~ =Q Sigma
The specimens that were taped to the note were examined with the SEm/Eox . They had
some Mg materials on them, but the bulk of litter that was found on them was NaCI . Its
significance is unconnected to the incendiary problem at this time .
GUY SPENCE
Cc : Dr . COOPER REES
Page 8

Document 6538392

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