"We would like you to test these items for the presence/absence of EDTA in order to refute the possibility that the stains on the sock, item 13, could have come from Nicole's reference sample, 59 or 72. Similarly, we would like you to test item 117 to refute the possibility that it could have come from Simpson's reference sample, no. 17."
KEY QUOTEDid you interpret by the way that request was made as a request to do some testing and they wanted a particular result?
Did you, when you approached the testing that you did, did you do it with an idea that you were trying to get one result as opposed to another result?
Now, let me show you the first page of that letter and could you read just the first sentence.
"This letter is to describe the items we are sending to you in order to detect the presence or absence of EDTA in specific bloodstains which are of significance in this case."
Now, were you ever requested by the Prosecution by way of this letter to try and quantify the amount of EDTA should you find it?
Mr. Martz, up to the time that you were contacted by the Prosecutors in this case, have you ever worked in any manner or fashion with EDTA?
Had you ever been asked to determine whether it was present in blood or any other substance?
Had you ever been--ever attempted to design a test to extract EDTA from dried bloodstains?
Now, is the technique that you used that we have been talking about yesterday, the--I want you to tell us what that technique is called.
The more conventional chromatography with mass spectrometry would be gas chromatography.
Now, did you hear yesterday Miss Clark asking some questions about the effect or the relationship between electrospray and chromatography?
But does chromatography--I'm sorry. Is electrospray involved in the chromatography stage at all?
Right. That is the way that we do electrospray at the FBI laboratory with liquid chromatography.
No, the chromatography precedes the electrospray. They work in conjunction. You need--in order to do electrospray you need a liquid, so to get the liquid you use liquid chromatography.
But the method of chromatography--the electrospray happens after the chromatography is done; isn't that right?
Now, you use liquid chromatography--you indicated that gas chromatography is a more commonly used procedure?
Not without manipulating the chemical EDTA. EDTA will not gas--work on the gas chromatography.
It is a technique that could be used. I have not tried it with EDTA. I don't know how successful it is.
And would you agree that that form of chromatography is much better than the form that you used?
Now, are you familiar with the method of liquid chromatography called gradient elution?
Now, do you know whether that is a better chromatography procedure for what you were trying to do than what you did?
Now, did--were you listening yesterday when there were questions being asked about the efficiency, if you will, of your chromatography method that you used?
And could you tell us whether your method does not effectively separate compounds by retention time?
It does not. It--the way that I used it, it is not very effective in separating compounds. I can give you an analogy. If everyone in here was to run a marathon, people would finish at different times. Very few people would finish at two hours. Some people may take six hours. Well, with the type of chromatography that I used it would be more like a 50-yard dash. We would all run a 50-yard dash. We would all finish about the same time.
You are familiar with other methods of chromatography that work better than the one you used, aren't you?
My purpose in chromatography was not for identification. I did not even consider that in the identification of these compounds.
Agent Martz, are you familiar with other techniques of chromatography that would provide better information in terms of separating compounds than the one you used?
The one did not involve mass spectrometry. I was able to use a compound which is not very friendly to the electrospray.
Now, so the first step that you tried on February--February 22nd is where you tested for the first time under the method that we have been talking about, the sock and the gate stains; is that correct?
Well, not necessarily. I mean, the 19th I did a method of electrospray mass spectrometry.
All right. So it was after you used that method that it was ten times less sensitive that you used the positive ion mode that we have been talking about that is more sensitive, correct?
You knew at the time that you did the negative ion mode, once you saw the results, that it was not a particularly sensitive test; is that correct?
So is it fair to say that you decided that you needed to do something a little bit more sensitive?
Now, if the method that you chose for the liquid chromatography was not particularly good, what was the purpose of doing it?
Well, I have a very expensive instrumentation that has unique capabilities. One of those is to separate out by masses. This is a tandem mass spectrometer. I can get much better separation using the mass spectrometer than I can the chromatography and I elected to use the chromatography for the introduction of the sample to the mass spectrometer or the first quadrupole.
Let me ask you again, was there a reason why you used the chromatography stage if you didn't really need to and it wasn't a particularly good method?
I didn't say I didn't need to in this particular case. With EDTA it is needed for it to ionize, otherwise it would have to be derivatized. Using--you cannot do direct injection of EDTA through solid probe or you cannot do it through GC/MS. The technique that I had available was the LC/ms using electrospray.
How much time did you spend designing the method that you were going to use in this case?
Umm, that is difficult to determine. I mean, it includes twenty years' experience that I have with mass spectrometry, knowing all the things about the instruments, what is available, what will work, what won't work, it would be very difficult to put a time on how long it took to develop this procedure, because it encompasses twenty years' of experience or eighteen years' of experience with the instrumental technique. The actual hours performing the EDTA analysis was probably in the order of maybe a week would be a good estimation.
And when you were requested to do this testing for the District Attorney, did you--was it your understanding that you had to develop a method that would work?
Well, I wouldn't necessarily develop a method. The method is already developed for the identification using electrospray. All I had to do was identify a different chemical. There is no really method development.
In order to get a procedure that was--was sensitive enough, in order to distinguish between a blood that was preserved with EDTA and blood that wasn't.
By the way, is the method that you used--any of the methods that you used quantitative methods?
So the purpose of the test, the way you at the time set it up, is it fair to say that what you were trying to do is just determine is EDTA there or isn't it?
No. I was trying to determine whether or not the stain came from EDTA-preserved blood.
KEY QUOTEAnd the method you chose was a method that would identify it but not quantify it? Is that accurate?
That would easily distinguish between whether or not it was preserved or non-preserved.
Was your method designed to determine whether it was there or not, as opposed to telling you how much was there?
No. My method was designed to determine whether or not it was preserved blood with EDTA.
Agent Martz, let me show you first chromatograms 1262-A and 1262-B. And do you recognize those?
These were 50 part per million standards that I had run of EDTA on--I don't see the date here, but was this on the 22nd?
Now, Mr. Martz, would you look at the chart, please, and tell me if that accurately charts the ion count that you got for 50 parts per million on two separate runs on February 22nd?
Well, I think a more accurate representation of ion count is the area and not the peak height.
Does your electrospray method result in ionization that widely or fluctuates from a large extent from one test to the next?
So as I understand your testimony, you think that my chart is misleading because I have it based on ion counts?
Well, it depends on what you are trying to prove. If you want to say that the instrument fluctuates, you wouldn't use the peak height, you would use the peak area because it is a better representation of the total ion count.
But looking at the peak height also demonstrates that it fluctuates quite a bit, doesn't it?
And would it be unusual, as we have here, as we have a seven-fold difference looking at the same thing, the same day?
It depends. From injection to an injection it would be somewhat unusual, but at the beginning of the day versus the end of the day it may not be that unexpected. And again, if you really want a true depiction of the good fluctuation, you would want to look at the peak area; not the peak heights. And the areas--
Does the peak height in your opinion bear any relationship to the quantity of EDTA that you are looking at?
Okay. Do you agree that if you look at area or ion peak your method of electrospray causes--you would expect that it would cause substantial variation from one test to the next or could?
Agent Martz, would you look at the monitor and tell us if that appears to be not to scale, but an accurate depiction of where you got Q206 from?
And when you got the sock was the green area indicated on the chart already cut out?
Now, you were also sent A--another swatch inside a little aliquot tube, were you not?
You never ran a test on that in the positive ion mode, the mode that we have been talking about, for Q207, did you?
And Q207, so--is it pair to say you made no estimate on Q207 as to how much blood might be on that?
Umm, by looking at it, it appeared that it was covered with blood, but how much, other than it was covered, I don't know.
Now, why didn't you test Q207, which was from the large stain, in the positive ion mode?
Mr. Martz, could you take a look at 1263 and tell me if that is a picture of Q207?
All right. 1263 will be the letter and 1264 will be a photograph of Q207. 1263, what is the date on the letter, counsel?
And you now know that that came from the stain area that had been cut out of the sock?
Once you found out what that was, did you ever request to have it sent back so that you could run tests, positive ion tests on that?
Agent Martz, is the chart that is now on the screen an accurate depiction of the two tests that you ran on Q206, the stain from the--the cutting from the edge of the stain?
And do you agree that the peaks demonstrated on the chart were peaks that you found in your testing?
Now, would you agree that you detected the presence of the 293 parent ion which is the parent ion for EDTA?
Well, isn't it true that the machine is set so that it only let's through the 293 parent ion?
So is it accurate to say that you can conclude from that chart that you have found both the 293 parent ion and the 160 daughter ion?
All right. Now, Agent Martz, would you agree that the pattern that you got on the sock, Q206, is consistent with the presence of EDTA?
Well, in this particular case I'm looking for the 160 to be the base peak, the 293 to be the second largest peak and the 132 ion to be about a third the size of the parent ion, so I'm looking for three ions in certain ratios.
Now, you have already detected the 160 in the parent ion and in this sample, have you not?
Now, what is the range that you scan in looking for the 132 daughter ion with this chart?
Now, did you--were you following the analogy that we were talking about yesterday of a TV camera panning back and forth?
And would you agree also that under that particular method it is--if 132 is there you are not going to be looking at it very much at all?
Well, it is relative. I mean, every 1.5 seconds I am looking at it for a considerable amount of time. It is all relative.
It was similar to the first technique that I had used. It is certainly more sensitive than this technique that I use for the confirmation.
Now, when you were looking for the 160 daughter ion, the scans that you did were generally from what range to what range?
Now, is it your experience that your machine drifts that much so that you need to have that wide a range?
Every now and then you will have what is called a dynamic mass spectrum where everything comes out and you will get every ion, so to avoid the possibility of a misinterpretation I scan on either side to ensure that the mass that comes out is the mass that I'm looking for. In other words, if mass 160 came out along with every other mass I wouldn't be able to distinguish that was the 160 only. I'm very interested in detecting 160 and no other ions, so I always scan on either side to ensure that a mistake is not made.
And would you agree that you wind up with lower peaks than if you were scanning just at 160 and it happened to be at 160 where it is supposed to be?
So that particular method that you used, you sacrifice peak height for a little bit more range that you look at to make sure that you are not making a mistake?
Okay. And now, selected reaction monitoring is where you just look at 160, right?
Now, of those three methods, the full daughter that we had on the chart, scanning a range two to either side of 132, or selected reaction monitoring, that is looking just at 132, which is the least likely to find 132?
Now, when you decided that you wanted to determine whether the 132 was present in what you found from the blood on the back--on the sock, why did you pick the method that was the least likely to find it?
Because it is the most or the best way to positively identify a chemical. You've got to remember here you don't want to misidentify a chemical. If I identify something, I want to identify it to the exclusion of all other chemicals, and for me to do that I have to do this experiment.
And of the three methods we described, you used the one that was least likely to find this, correct?
I don't know that I agree with that. I mean, my purpose was to identify a chemical and this is the only means that I had to identify that chemical, and that is why I selected that particular--it had nothing to do with sensitivity. This is what I need to do to identify a chemical.
Okay. Was that the only method you had to identify the 132 method that you knew would be there if it was EDTA?
Objection. That is argumentative and also calls for speculation, assumes facts not in evidence.
Was this the only method that you had to identify the 132 ion that you knew would be there.
There is many methods to identify a 132 ion. This is not the only way to identify a 132 ion, I would agree with that.
Did you ever run a scan that looked at two sides from 130 to 134 to try and find the 132 daughter ion?
Did you ever use selected reaction monitoring to look just at the 132 to see how much might be there?
Let me show you 1260-A and 1260-B. I show you 1260-A and 1260-B and ask you to tell us what those are.
And using the positive ion mode that we have been talking about, you looked for that twice?
Hold on to that. Now, it is your understanding that this stain came from a bloodstain found on the back gate in Nicole brown Simpson's condominium?
Agent Martz, would you agree that the chart on the screen accurately portrays the two tests, the two positive ion tests that you did of the stain, the blood from the stain from the back gate?
Okay. And by the way, the retention time on these two charts and the retention time on the sock charts, are they consistent also with EDTA?
Now, would you agree that the two charts that are up on the screen from the gate demonstrate the presence of the 293 parent ion and the 160 daughter ion?
Would you agree that those charts--that what you found in those charts is consistent with the presence of EDTA?
Did you ever in these two samples look for the 132 daughter ion using a scan of 130 to 134?
Did you ever, with these two samples, look for the daughter ion by doing selected reaction monitoring, that is, looking just at 132?
Agent Martz, let me show you what has been marked 1265, Defense exhibit, and could you tell was that is?
Now, Agent Martz, can you look at your monitor. Is that an accurate picture of the sock after you did your cutting?
Now, it is a little difficult to see on the big screen, but could you direct the arrow to the part that you cut out yourself?
Did you examine--did you examine the sock to determine the outer edge of the bloodstain that had been in that area?
So it is your understanding or your recollection that the bloodstain came out further than the edge of your cutting?
Now, this is what you were just describing as the cut-out on the sock that you made?
Now, did you do any testing at all to determine whether there was more blood in Q207 or less blood than there was in Q206?
Is it accurate, Agent Martz, that--let's assume hypothetically that Q207 had more blood in it than Q206. Do you have that in mind?
Would you agree that if that stain had been made with EDTA blood that you would likely find more of it in Q207 than Q206 if Q207 had more blood in it?
Well, when you are trying to detect EDTA, would you agree that the amount you are likely to detect, if it is there, is going to be dependent on how much you start with in your testing?
And if you start with less blood that has EDTA in it, would you agree that you are likely to find or have a lower likelihood of finding EDTA than if you had a larger quantity of blood with EDTA in it?
Well, certainly it would depend on the size we are talking about. If we are talking very small differences, you may or may not, but if we are talking large differences, then you will find differences.
Did you do any testing whatsoever to determine whether the amounts of blood in the sock--let me rephrase. Did you do any testing to determine whether the concentration of blood in that large stain varied from the outer edge to the center?
Well, I didn't even have the center, so it would have been a difficult test to determine.
If you wanted to you could have extracted the blood from Q207 and compared it to Q206, couldn't you?
Well, is the reason that you didn't do that is because you didn't know what Q207 was?
207, I didn't know exactly what it was. That is why the first day I combined 207 and 206 and treated them as the same, because I didn't know the origin of 207.
Now, Agent Martz, do you agree that in order for EDTA to be detected in your method, it must be water soluble?
In other words, a compound that might have the same molecular weight and the same daughter ions as EDTA, if it wasn't water soluble, you wouldn't be able to measure it under your system?
Well, it depends, too. I mean, when you are talking about parts per million, parts per billion, in literature a lot of time they will report things as not soluble in water and yet in reality you can identify things and trace quantity. It would depend on the individual chemical.
Well, not necessarily. I mean, when you are talking parts per billion or million, and you are talking about a complex mixture, we put in solution things that literature says that are insoluble in water and identified them. I mean--
When they say soluble, in referring--they are not referring to parts per million, parts per billion.
There are a lot of things that are not listed as not soluble in water that will dissolve in water.
Would you agree that for a compound to have the characteristics of EDTA that you found it would also have to be heat stable?
Well, yeah, but what heat? Are we talking about? Are we talking about a hundred degrees, 500 degrees, a thousand degrees? I don't understand--I mean, that is a broad term.
Must the chemical that you are looking at, in order it to--to go through your system, be soluble in the specific mobile phase, that is, the liquid that you use to send it through the column?
Okay. Now, have you run tests on any other compound, other than EDTA, that gives you the results you got in this case for the gate and the sock; namely, the retention time that you got, the presence of the parent ion, the presence of the daughter ion?
Have you ever tested, in the course of your 17 year's experience with mass spectrometry, any chemical that has those characteristics other than EDTA?
Now, you have in the--I think yesterday been attempting to find some compound that might look like this?
Well, I have been attempting to find--locate other chemicals that could possibly give similar results, yes.
That is what I was told on the phone this morning. I don't have any other knowledge other than that.
Okay. And the mass spec that was generated there was done with a different method from your electrospray; is that correct?
Do you have any way of knowing, without estimating whether if you have run the same tests on that, whatever it is, that you would get the same pattern as EDTA?
I have no way of knowing other than testing. The purpose for this chemical is it had some properties similar to EDTA in its mass spectrum, but the only way to prove whether or not it would give the same result or not would be to actually analyze the chemical.
Once you got the results that you got in this case in February did you make any effort to find some compound other than EDTA that would account for what you found on the back gate and the socks?
Do you recall the testimony yesterday about the EPA documents that were presented by Miss Clark to Dr. Rieders?
Let me show you 12--I'm sorry, People's 537. Is that the reference that you are thinking of?
It is Brit, so I don't know if it is the British or the Britain, but "Vet" is evidently veterinarian and "J" is obviously journal.
Did you recall yesterday Miss Clark asking Dr. Rieders questions about that document as it relates to the maximum daily allowance of EDTA?
I don't know if it necessarily had to do with maximum daily allowance or what you would expect to find in a person. I think it was more relating to how much you would expect to find in a person's blood.
Does that abstract indicate that you would expect to find 2000 parts per million in anybody's blood?
Would you agree that if someone had 2000 parts per million EDTA in their blood they would be dead?
Well, for any sustained period of time. I think they use it also for transfusions. I don't know the exact amount that they use. It would not be a good idea, I don't think, to have that amount in your blood, I agree with that.
Does that number bear any relationship at all to what the FDA allows in terms of EDTA as a food additive?
No. I did some further research and actually the whole reference has to do with how much EDTA is used to preserve food. It has absolutely nothing to do whatsoever with how much you would expect to find in fish or humans. It was completely out of context.
Okay. Now, I want to ask you about EDTA that you might expect in your blood from food. And you have provided us several articles that you found related to that topic, have you not?
Let me show you 1267. Do you recall Miss Clark yesterday mentioning the figure of 50 milligrams per day as a possible amount of EDTA that someone might take into their system?
It is the "Food iron absorption in man. The effect of EDTA on absorption of dietary non-heme iron."
Now, you also were shown yesterday some excerpts from the code of federal regulations. Do you recall that?
I show you People's 539. Take a look at that again. Is that the document that describes what the FDA says is the allowable maximum amounts of EDTA in food preservatives or food substances?
And I would like to put that on the elmo again. Now, this is a document that you provided to us as well, is it not?
Now, it is your understanding that the 50 milligram per day figure that is in that article that you provided to us was based on what the FDA says are the maximum levels of EDTA you can put in food?
Now, this regulation talks about parts per million, 220 parts per million, 33 parts per million. That bears no relationship to parts per million in food, does it?
Now, you also provided us a study from 1954 concerning the metabolism of EDTA in humans, correct?
Umm, I don't think it primarily dealt with metabolism. It was an article about EDTA being injected in humans. I think--
--I think they did mention it was not metabolized, but I don't think that was the purpose of the article.
Now, what is your understanding as to the body of literature on EDTA, such as it is, in terms of how much EDTA that you eat in food actually gets into your blood?
Umm, it is unclear. The best is that paper there from 1954, but even in that paper it mentions some data which is conflicting and there hasn't been a whole lot of data since then. Most of the other papers even today refer back to that paper in 1954. I believe it is not well-known.
I think all the other literature is based on that, to my knowledge. There is no other independent study that I could find.
Well, what is--you provided us some other literature that says the same thing, didn't you?
Yes, yes. I mean, it was mentioned in a lot of articles that that was the absorption, I agree with that.
Did you provide us with some excerpts from a textbook called "The pharmacological basis of therapeutics by Goodman and Gilmans?
What does that indicate in terms of the absorption of EDTA that you take in by mouth into the blood?
Now, when we talk about absorption into the blood, when you eat something, it doesn't just go into the blood, does it?
What happens to it in the stomach in terms of how it gets to the blood versus how it gets excreted in other ways?
Well, we are trailing a little bit out of my field, but certainly in order to survive things have to be absorbed into the blood stream. If you eat everything and nothing gets absorbed, you are going to die.
Now, the studies indicate, the `54 study indicates that the vast majority, ninety percent or more of the EDTA that you might eat gets excreted through the feces and never gets to the blood, correct?
When we talk about a five percent absorption rate, we are talking about of the, let's say, of the 50 milligrams that a person might eat in a day, only five percent of that actually gets into the blood at some point?
Now, that paper also talks about when it gets into the blood stream that it also gets into other extracellular fluid, in other words, other fluid in the body, correct?
I think the paper there may have used forty liters. It would depend of course on the size of the individual, so that would be probably an average.
Now, would you agree that it is a relatively easy calculation to figure out if you had 2.5 milligrams in forty liters how much parts per million, billion or whatever that is?
I believe it was sixty parts per billion, approximately. Approximately sixty parts per billion.
We are talking in the range of parts per billion rather than parts per million, correct?
Now, under that set of conditions that I just described to you, that assumes, does it not, that whatever gets absorbed into the blood is all there at the time that you take the measurement?
Now, what does the literature indicate in terms of how quickly EDTA that does get into the blood stream gets out of the blood stream?
Well, its half-life is very short. It leaves the blood stream very quickly, according to that paper.
And by "Half-life" does that mean that once this, let's say, sixty parts per billion gets into your system, one hour later there is only going to be half as much?
Now, would you agree that under those circumstances that we have described that is consistent with the literature, that the amount of EDTA that you might expect to find in a person's blood after they ate something with EDTA in it is likely to be very, very small, in the range of parts per billion?
Well, I think if you take everything into account it would be difficult to say that. I mean, you are looking at one study in 1954 and it mentions at the end of that that there its some conflicting data based on iron and yttrium being eliminated very quickly from the body when it is ingested, when EDTA is ingested, and that paper only mentions one of the salts that the FDA permits to be used in the food. There is two other salts. So relying totally on one paper in 1954 with a lot of other conflicting information and information that is not available, I--to be perfectly honest with you, I don't believe that anyone knows exactly how much EDTA is present.
Well, when you say a lot of conflicting information, what conflicting information are you talking about?
Well, conflicting information with iron studies, the fact that it indicates that more is absorbed than the five percent.
Now, the paragraph you are referring to is the one that has the little asterisk in front of it; is that correct?
"The low absorption after oral administration is very surprising in view of the findings that material"--
Objection, your Honor. Could we ask Mr. Martz to speak into the microphone. I can't hear.
"The low absorption after oral administration is very surprising in view of the finding that the material is effective by that route in accelerating the excretion of yttrium and lead. There is no satisfactorily readily apparent explanation at the present time" or "At this present time."
Now, would you agree that what that says is that EDTA is able to help remove yttrium and lead from the blood very quickly?
And that doesn't say that EDTA is absorbed more than five percent in blood, does it?
It is a chelating blood. Once it goes in the blood it chelates and gets in the body and will be excreted.
Ladies and gentlemen, we are going to take our mid-morning recess at this time. Remember all my admonitions to you. We will be in recess for fifteen minutes. And Agent Martz, you can step down and we will be back in fifteen minutes.
We would like you to test these items for the presence/absence of EDTA in order to refute the possibility that the stains on the sock, item 13, could have come from Nicole's reference sample, 59 or 72.
Yes... it certainly warrants further testing. It responded like EDTA responded, yes... Yes.
I don't know right offhand... I don't think that I have.
No. I was trying to determine whether or not the stain came from EDTA-preserved blood... My method was designed to determine whether or not it was preserved blood with EDTA.
Agent, the world's best is 2:06.