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06-22-2011, 10:09 AM #1
DIRECT EXAMINATION OF MICHAEL SIGMAN BY CM
He is a faculty member at UCF. He has a PhD in chemistry. Joint appointment for the National Center for Forensic Science. BS in 1982 from SW Missouri State University. PhD in 1986 from FSU. He was an NIH post doctoral fellow at the University of Illinois and the University of Chicago.
He worked for 1 year as a research scientist for Dow Chemical. Staff scientist at Oakridge from 1990 to 2002 and then went to UCF.
He has known Dr. Vass since 1990.
Peer reviewed articles - he has 74 publications and book chapters. He's lectured 140 times.
Witness tendered as expert in Chemistry with no objection by JA
On 7/21/08 he received a call from Eric Walton from UCF police officer asking him to speak to Eric Striker about air samples from the car.
Striker told him he had talked to Dr. Vass and they wanted air samples taken from the trunk. Dr. Vass gave his name.
He then called Dr. Vass to ask what type of samples he wanted and what methodology to use. He knows Dr. Vass uses sorbent traps and said he didn't have any Discussed the use of a Tevlar bag and Dr. Vass said that would be acceptable.
He and his associate pulled a liter of air from the air and then 300 ml and put them in a second one. They did not have a pump, so they used a syringe. Trunk was closed when he arrive - opened it up just enough to extract the sample. He left the samples with OCSO - the larger bag was to go to Dr. Vass and the smaller bag went to UCF National Center for Forensic Science.
The first test they ran - they extracted 250 mcl from the bag and injected it into a GCMS. He then explained how the machine works. It is a widely used and well characterized method for doing chemical analysis.
They analyzed the sample and the results showed that there were trace amounts of volatile organic components, but the signal was not strong and the sample was not concentrated enough to be usable. The components were comparable to gas or other petroleum products.
In the first sample, the sample was too weak. They then took a second sample of 330 mcl using a solid phase micro-extraction fiber. This sample had a better signal. They determined if they wanted a better sample, to use the solid phase technique and the results were again consistent with gasoline.
He did not do any quantitative analysis.
Second sample identified several components of gasoline.
On 7/22/08 they returned with a solid phase micro extraction fiber and carbon strip for 40 minutes. They then placed them on ice and returned to the NCFS and analyzed them. The next day they went back to OCSO and left the solid phase and active charcoal filters for 7 hours. These samples had a stronger response showing a primary pattern of gasoline and that there was present in the sample chloroform ( solvent and also formed from the reaction of bleach with organic components in the environment), dimethyl disulfide (present in onions and cabbage and decomp).. and tetrochlorol ethyline (used in dry cleaning or degreaser). A quantitative analysis was not done, but could have been done.
He has not done direct studies on decomp. It is reported by Dr. Vass and Dr. Steferopolis that there are a whole host of compounds released in decomp.
It is his opinion, based on his samples and analysis, the three compounds were present, but gave very low readings, based solely on his data and test he could not conclude that there had been human remains in the trunk.
He understands that there was garbage found in the trunk of the car.
He took a total of 6 air samples - 2 tevlar bags, 40 min solid extraction fiber, 40 min carbon strip, 4 solid base micro extraction fibers.
The solid phase micro extraction fibers (40 min) and two 7 hour exposures contained the three components. They were not found in the tevlar bag.
No further questions.
15 minute recess. (10:09)
06-22-2011, 10:09 AM #2
CM w/Michael Sigman - (sorry missed his CV)
peer reviewed journal - articles submitted - sent to people in field - peers make reviews and submit to editor - decision to publish or not.....
peer reviewed articles published and over time since received PhD made 140 presentations and in conjunction with students....expert witness in chemistry
Dr. Sigman - first came involved in kc case...on 7/21/08 in lab received a phone call from Eric Walton LE asking to speak to Mr. Striker from OCSO re: take samples of air from car belonging to KC....wanted to take air samples from car...Dr. Vass not available to take samples - Dr. V gave his name to take samples air from trunk..
first called Dr. V asked what type of methodology to use....I didn't have absorbent traps...asked to use a Tevlar bag - he said that would be acceptable....it is made of polymer commonly used to collect air samples.....
Doug Clark an associate who works in lab with me and myself proceeded to OCSO took tevlar bag and gas syringe - pulled 1 sample of 1 liter of air in tevlar bag and then pulled another amount and put in smaller bag
usually have a pump to pull the air....we didn't have pump....but used a gas syringe by opening trunk just enough to get needle in to pull the air....second sample approx. 300 mililiters in tevlar bag....left both samples with OCSO - larger bag sent to Dr. Vass and smaller bag they brought to us the following morning to test
first test ran used a gas syringe - pull 250 microliters of hair used GCMS to examine air....GCMS like an oven - oven component a very long g lass capillary 25-30 meters in length.....micron is 1 millionth of a meter....25 micron film is 25 mm of a meter....inserted generally by a syringe - pass thru column- mixture components will separate out into bands...come out into mass spectrometer the detector for this instrument....eletrons in the source 70 electron volts - pass very close to electron molecules - create positive charge on molecules directed thru mass analyzer - mass of molecule to charge of molecule....molecule have a weight - pieces break into and mass to charge ratio of that we can identify.....widely used chemical analysis...very stable used many times.
we analysed 250 microliter of air pulled in syringe results obtained from GCMS showed trace amounts of volitle organic compounds but signal not strong - sample was useable .....left the big bag with OCSO - not sure if sent to Dr. Vass....test of 250 microliter saw organic components very weakly in soil.....hydrocarbons like in gasoline ....ordinary gasoline yes....find any others? in first sample it was too weak...used a different methodolgy to extract air....very thin glass...with polymer coating ...fiber contained within metal needle...extend fiber from needle and leave for extended time...retract fiber from needle- remove need and put into GCMS insert needle in injection port 250 Degree centigrade- organics go thru polymer and into GCMS....what components extract in 2nd sample very similar to first sample much more concentrated we had a better signal - with solid microextraction...consistent with presence of gasoline....able to do a quantative analysis No, not any.....
what compounds identify? in 2nd sample identify tolulene, ethobenzene, componenets typically in gasoline......in testing determine some amounts of ?choro-ethene?
want to refresh memory look @ report
do not believe in sample 2 = petrochloro=etheline...
got some samples later. returned to OCSO garage - sample from car solid phase and carbon strip...took back to Nat. Center for Forensic Science - placed on ice - looked @ them immediatly after return.
next day picked up samples left in car 7 1/2 hours....analytical result ...analysed same day as well....with those samples better and stronger than saw in tevlar bag...primary pattern was gasoline also determined also chloroform, dimetro ....and tetrochloroethelyn
quantitative analysis was not done...primary was gas then other three.....tetrochlor ethely...used in dryclean and can be used as a degreaser - (object-
what compounds found in air.
gasoline, chloroform, dimethol disulfide and tetrochloroetheline......chlroform solvent in chemical labs and degreasing applications and find in natural settings formed in reaction bleach and organic components....clorox...sodium hypochloride...
dimethal disulfide = occur naturally in substances? yes in onions, cabbage, soil samples, reported in decomp as well...
based on your ed and train...are these sometimes emitted from decomp of human remains...haven't studied human remains...reported by Dr. Vass and Dr. Stephanolopolis...
all 3 are produced in human decomp - listed 30 in his paper but these 3 indicated human decomp....in 2005 Dr. S - reported list of 86 chemicals found from 2 decomp bodies found in Meditteranian sea....of 86 - 11 of 30 were listed by Dr. Vass....didn't list tetro chloro and chlroform....likely produced in anerobic conditions with no air present - based upon the literature...those compounds can be related to human decomp...in addition to cabbage/onions/cleaners and chlorox? yes...my opinion based upon sample we collected and analysed...3 compounds were present but they were @ low responses in instrument - we didn't quantify ....those sources are found in natural ...I could not concluded human remains in the trunk of car....were you aware garbage found in trunk? I do try not to follow details but I do know garbage was found in trunk....
CM - how many air samples take? total of 6 ...2 tevlar bags....th 40 min solid phase micro-extraction....40 min carbon strip.....4 solid phase microextractors -2 @ OCSO , 2 we analyzed and 2 carbon extractors....gasoline was principle GCMS profile could be attributed to gasoline....solid phase micro extraction from 40 min exposure and 7 1/2 hr exposures...contained those chemicals 3....didn't see those samples taken from tevlar bag and last carbon strip we analysed....strip it with carbon disulfide.....also didn't see the 3 compounds ....
air in 2 tevlar bags were done @ same time...
15 min recess
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06-22-2011, 10:48 AM #3
SIDEBAR #3 (10:28-10:31)
Jury coming back
CROSS EXAMINATION OF MICHAEL SIGMAN BY JA
Air samples from trunk which were put in Tevlar bags was done on 7/21/08. They opened the trunk about 1 inch to get the syringe needle in it. They did not open and inspect the trunk and did not know that the trunk liner had been removed 4 days earlier.
250 micro liters - 1 micro liter is 1 millionths of a liter. The syringe internal diameter was about that of a led pencil and the length of draw on the syringe was about 1/4 inch.
On 7/21 they pulled 2 samples - 1 liter and 300 ml - these were placed in the Tevlar bags and held by the OCOS. Mike Vincent brought him the 300 ml bag to him on the 22nd.
Dr. Vass wanted him to use a triple-sorbent trap, but he did not have one. this involves using a pump and gives you more air to sample. Each of the three sorbents gives different metabolites. You can test a large volume of air.
His analysis of the air sample showed some weak signals for organic compounds.
He then went to the solid phase fiber method. Though better than the Tevlar, still not as concentrated as the triple-sorbent. This will probably give a worse signal. The triple-sorbent trap is a better method than both. He used the best method he had available.
His sample tells what was in the air in the trunk - not where it came from.
He was still able to detect chloroform and the other components. These are listed as items coming from decomp as well as other sources.
Chloroform can come from a reaction between bleach and certain organic components. One report from an Iranian journal reported chloroform in pools and in people who swim in pools - in very minor amounts.
Should there be other components? Bromide could react and lead to chloroform but with other signature chemicals.
He's not aware of any literature discussing a bathing suit in a trunk causing chloroform to be present.
There is nothing in his results to indicate the source of the chloroform - they simply know it is there.
Decomp is not his specialty.
When he opened the trunk, he noticed an odor coming from the trunk. He does not have any background in identifying the odor.
REDIRECT EXAMINATION BY CM
Slight traces of chloroform was found in sample 3 - 40 minute fiber - and the 2 fibers from 7.5 hours also contained the 3 compounds.
He does not know the source of any of those three.
The predominant chromatographic profile was identified as gasoline.
No further questions.
RECROSS BY JA
It did not surprise him to find elements of gas in a trunk.
No further questions.
Witness is excused.
06-22-2011, 10:49 AM #4
JA date took air samples was 7/21/08 - needle syringe - inside trunk - 8" needle - didn't open and inspect the trunk no - didn't know the trunk liner was removed and spare tire cover removed 4 days before -no didn't know that....4 days after was the air sample....how much is 250 microliters...a micro liter is one millionth of a liter - about the size of width of pencil lead and length of draw on syringe maybe 1/4"....not very much air.....inject into tevlar bag....taken to lab
on 21st pulled 2 samples first one was 1 liter and second was
triple sorbent trap -
held by OCSO a deputy brought a 300 ml tevlar bag to ...on morning of 22nd...Dr. Vass uses triple sorbent trap by Dr. Vass
pull air thru 3 traps - each of them pull out different components - if you pull out 10 liters of air you get what was in 10 liters of air.
in air samples itself - some weak organic compounds then went to next level - ambiant air and allow chemicals to attach itself to ...but that sample method isn't as good as triple sorbent trap- the triple sorbent trap a better methodology for sampling @ low concentrations of air sample....a better method than casrbon strips...used best method to try to determine what was in air in trunk....doesn't tell you where it came from....if a particular object in trunk - if those items were isolated and test the air to collobrate to equalize the amount of the compound in the air....one methods to place item in tevlar bag to offgas - acceptable approach....
even with methods able to use...with trunk liner gone - still able to detect chloroform and TCE and dimethaldisulfide.....on that limited sampling those chemical are consistent with research out there about human decomp - those components are in peer reviewed lit....can come from other sources as well..
chloroform can come from bleach and reaction with other components....in literature in finding it in swim pool water - one article where chloroform was in swim pool - minor amounts and there should be other components when chlorine and chemical components....if bromine is present and chlorine together hypobromois acid ...methane and hydrochloro acid....as long as bromide there to form hypobromis acid...
any case in literature about chorine caused by bathing suit in trunk or accidental create chloroform with chlorine (cl2) natural form of chlorine...suspect that material hydrolize with water or dissapate....anything in your eval of air sample that chlorine came from some inadvertant reaction between pool chlorine and ......nothing in our results to indicate source of tetrochloroetheline and the other there.
ed is not in human decomp - odor from trunk when you inspected it...but no back g round in identify odor...
redirect- CM -
found these slight traces of chloroform in only 2 samples tested in 5A and 5B? no sir I believe it was the #3 40 min micro-extract and the 2 solid phase from 7 1/2 hrs also contained those compounds....don't know the source of any those 3.....main thing there was gasoline? the predominat chromatograph profile was gas....created report on 7/30 3 years ago....based on circumstances car in garage - trunk liner removed - surprised to find elements of gas.....No not surprised to find that
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