DDT or PCB?


One of the key hoax points of the pro-DDT crowd claims that most early studies on the harms of DDT — from 1945 into the 1970s — must be dismissed because chemists then could not distinguish DDT from PCBs.

Chemically, were that the case at any point, modern methods of spectrophotometry would allow the retesting of tissues, or egg shells, or anything sampled years ago.   Why not retest?

I stumbled into this interview with Art Cooley, one of the early activists with the Environmental Defense Fund (EDF) (now just “Environmental Defense”).  In it, Cooley said that EDF had been able to establish that DDT can be distinguished from PCBs.

Which case is he talking about, in Wisconsin?  What was its outcome?  Which research papers, where, discuss how to tell DDT from PCBs?  This appears to be one more point where the hoaxsters exploited a general lack of specific information about a case.  What will the record show?

Climate Action Can’t Rest: Q&A with Art Cooley

August 12, 2010 | Posted by Sam Parry in climate action report

Sam Cooley, a founder of EDF

Art Cooley, one of EDF's founders, offers his perspective on the climate fight and the road ahead.

With the Senate apparently giving up on its efforts to pass a strong climate and energy bill this year, we took some time to talk with several EDF experts to help provide a broader perspective and describe some of the other important ways we are fighting to cut global warming pollution.

We begin this series with Art Cooley, who helped found EDF in 1967 to campaign against the use of DDT. Art remains on EDF’s board as a founding trustee.

Question: You helped found EDF more than 40 years ago. Can you tell us a bit about the early years and what EDF’s mission has been since?

We originally got started because we were concerned about the decline of ospreys on Long Island. We started by looking at the science and the case we put together — the effect on brown pelicans and peregrine falcons and bald eagles and ospreys — was compelling. It was DDT.

In one of our first cases in Wisconsin they tried to confuse the debate and tell us that we couldn’t differentiate between DDT and PCBs. Well, we plotted out evidence and showed that in fact yes we could tell the difference, and so weren’t confusing the effects from DDT with other chemicals.

That focus on science has always been central to our work. And getting the science right remains at the core of our mission today, which is why we are all so concerned about climate change.

10 Responses to DDT or PCB?

  1. Ed Darrell says:

    Thank you for dropping by, Mr. Cooley!

    Dr. Naomi Oreskes’ Merchants of Doubt has a very concise shutdown of the pro-DDT propagandist’s claims, and I agree it’s at the top of the heap in terms of accuracy in telling this story.

    Do you know if Wisconsin has that hearing record on line somewhere? Might you have a link? I’ve been searching without great success.

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  2. Art Cooley says:

    Dear Bathtub: No one would have been happier than the manufacturers of DDT to have successfully claimed that DDT and PCB could not be distinguished. And, they tried. Indeed, by gas chromatography techniques, they can be separated and in testimony at the Wisconsin Administrative Hearing on DDT it was shown that they could be separated and so not confused. In addition feeding birds with DDT produced thin egg shells and feeding birds with PCB did not. Now all these years later, innuendo and suspicion are raised where no doubt occurred forty years ago. Read The Merchants of Doubt if you don’t think science is being subverted to political and monetary gains.

    Like

  3. j a higginbotham says:

    Nick K, Cute, but I’ll stand by my statement as that story illustrates my point.

    The paper mentions nothing about “seeing” molecules. AFM is more akin to feeling something than seeing it. It is the measurement of the deflection of a tip scanned over the surface examined.

    How they work:
    Vision: http://en.wikipedia.org/wiki/File:Eye-diagram.png
    AFM: http://en.wikipedia.org/wiki/File:Atomic_force_microscope_block_diagram.svg

    paper
    http://www.sciencemag.org/cgi/content/full/325/5944/1110

    jah

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  4. Nick K says:

    Higgins, what was that about not being able to see molecules?

    http://www.scienceinseconds.com/episodes/Seeing-Molecules

    To quote: While it’s true that your prof is probably giggling inside watching an auditorium of fumbling undergrads attempt 3, 4-dimethoxybenzoic acid, the exercise is not futile. According to a 2009 paper written by a group of IBM researchers, those chemical structure models appear to be very close to reality, as they managed to take the world’s first picture of a molecule.

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  5. j a higginbotham says:

    Hi PeterG

    The main problem is that we cannot see molecules. So how does someone identify a compound? There are a number of analytical techniques, many of them complementary, which look at molecular properties. [This is similar to the blind men and the elephant – different approaches give different types of answers and none alone guarantees identity.] Exacerbating this problem, most of the samples analyzed for contaminants contain only very small quantities of many different chemicals.

    One of the papers I referenced before mentions a 1940’s paper in which the authors measured the amount of organic chlorine in a sample. This obviously says nothing about the type of molecules which incorporated the chlorine. This kind of test is only valid when you know what chlorine compound is in a mixture and want to determine how much is present.

    The main methods for studying ddt and PCB’s became commonplace in the 1940’s and 1950’s. Chromatography is a technique in which a mixture of compounds is passed over a coating of some compound. Different compounds interact to different degrees with this coating so that they take different amounts of time to pass over the coating. In the simplest form, the only characterization is the retention time. Therefore unknown mixtures have to be compared with standard known compounds. [There is a large number of different coatings which separate compounds according to different features. See page 16 on in http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/General_Information/t407133.Par.0001.File.tmp/t407133.pdf%5D.

    I already gave a 1995 procedure for determining PCB’s and ddt (http://nwql.usgs.gov/pubs/OFR/OFR-95-140.pdf). I do not have access to the 1969 through 1971 papers which describe the problem.

    http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/Application_Notes/t006404.Par.0001.File.tmp/t006404.pdf has a picture of the results for this
    Application Report 404
    US EPA Method 608, 8081, OLM04.2 Organochlorine Pesticides on the 20 m x 0.18 mm I.D., 0.36 μm SLB-5ms
    This is the analysis of a 22-component standard containing 20 pesticides and 2 surrogate compounds commonly analyzed by US EPA Method 8081. The greater efficiency of a 0.18 mm I.D. versus wider bore columns, allowed resolution of all 22 compounds in less than 20 minutes. The stability of the SLB-5ms at high temperature enabled the run to be taken to 325 °C to decrease the elution time of the last surrogate (decachlorobiphenyl).

    http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/Application_Notes/t006403.Par.0001.File.tmp/t006403.pdf shows pcb’s
    Application Report 403
    Aroclors on the 20m x 0.18 mm I.D., 0.36 μm SLB-5ms
    Aroclors are commercial mixtures of PCB congeners. Due to their stability, they have been used in many different in- dustrial and commercial applications. Because of their toxicity and ability to bioaccumulate, production of these materials ceased in 1977. This application demonstrates the separation of two common Aroclor mixtures, Aroclor 1016 and Aroclor 1260 on a 20 m x 0.18 mm I.D., 0.36 μm SLB-5ms. The higher efficiency of the 0.18 mm I.D. allowed for good resolution of the PCB congeners, and subsequent pattern recognition of the Aroclor mixtures, while maintaining an analysis time of < 20 minutes.

    You would have to look up a particular study to see if the authors may have confused PCB's with chlorine-containing pesticides.

    jah

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  6. PeterG says:

    I have a question for you J A HIGGINBOTHAM. In your post you say “ddt and pcb’s can be confused depending on technique but also can be distinguished” Could you please elaborate more on this. Also could you please provide a timeline of when DDT was being confused with PCBs. And what was the timeline when PCBs detection in environmental samples actually became possible. In other words in what year was detection of PCBs in environmental samples actually made possible so that DDT was no longer confused with PCBs and could be clearly distinguished from PCBs. So that the effects from DDT would not be confused with the effects from PCBs

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  7. j a higginbotham says:

    All links found with Google based on information in original post.

    Like

  8. j a higginbotham says:

    The rather aptly named http://www.junkscience.com contains this link to pcb/ddt detection issues http://www.junkscience.com/ddtfaq.html#ref11 [http://www.21stcenturysciencetech.com/DDT.html Lyndon LaRouche site].

    First page of http://pubs.acs.org/doi/pdf/10.1021/jf60190a050

    Element Specific Gas ChromatographicAnalyses of OrganochlorinePesticides in the Presence of PCB’s by Selective Cancellation of Interfering Peaks
    George C. C. Su*l and Harold A. Price
    Polychlorinated biphenyl interference-free quali- tative and quantitative gas chromatographic (gc) analyses of P-BHC, oxychlordane, heptachlor ep- oxide. p,p’-DDE, o,p-DDT, p,p’-DDD, p,p’-DDT, and Mirex in the 10-25 ng range have been car- ried out in the presence of approximately 10 to 20 times their concentrations of Aroclors 1232, 1248,
    The belated recognition of polychlorinated biphenyls (PCB’s) as a source of potential threat to the ecosystem, coupled with their large-scale employment (about 600 million lb manufactured in the U. S. between 1960 and 1970), has resulted in the inadvertent introduction of enormous amounts of PCB’s into the environment (Broad- hurst, 1972; Jensen, 1966). Consequently, PCB’s have been found in wildlife and humans in most of the so- called advanced regions of the world (Holmes et ul., 1967; Koeman et a/ 1969; Price and Welch, 1972; Risebrough and de Lappe, 1972; Risebrough et a/.,1968; Widmark, 1967;Yobs, 1972).
    There are a total of 210 PCB isomers with varying boil- ing points, gc retention times (Cook, 1972), and toxicities (Bitman et a/,1972; Hoopingarner et al., 1972; Zitko, 1972). They interfere in the gc determination of virtually all organochlorine pesticides (Fishbein, 1972; Reynolds, 1969; Zitko et 171. 1971). This has given rise to much con- troversy in pesticide analyses (Reynolds, 1969) and may be the principal reason for the difficulty in recognizing PCB’s as environmental contaminants.
    Attempts to separate organochlorine pesticides from PCB’s have largely been unsatisfactory. Existing methods of separation are either inefficient and time-consuming or subject to problems of reproducibility (Armor and Burke, 1970, 1971; Porter and Burke, 1971). Quantification of or- ganochlorine pesticides has, thus, often been shrouded in clouds of uncert ainty and controversy.
    Recently, two methods have been reported for the rapid, interference-free detection of organochlorine pesti- cides known to be contaminated with PCB’s.
    The first me1hod involves the irradiation of a pesticide- PCB mixture (Leavitt et al , 1973). It takes advantage of the fact that PCB’s are photochemically degradable to mono- and dichlorobiphenyls (Ruzo et a / , 1972), which have shorter gc retention times than many organochlorine pesticides or their photoproducts.
    The second method calls for modification of the Coul- son conductivity detector for gc and its operating parame- ters (Dolan et a1 , 1972). The paper discusses the detec- tion of dieldrin and heptachlor in the 100-ng range in the presence of Aroclor 1254. No mention was made of any at- tempt to quantify the two pesticides studied.
    The Coulson conductivity detector is a versatile ele- ment-specific gc detector (Coulson, 1966) which can be operated in the oxidative mode or in the reductive mode with or without a catalyst (Tracor, Inc., 1971). The proper
    Michigan Department of Public Health, Lansing, Mich- igan 48914.
    Present address: Michigan Department of Natural Re- sources, Lansing, Michigan 48914.
    1254, and 1260 by the use of the Coulson electro- lytic conductivity detector in the noncatalytic re- ductive mode. No modification of the detector system was necessary except to set the detector’s reactor temperature at 660″. The results on indi- vidual analyses in most instances were within &20%of the actual value.
    choice of operating conditions may enable it to achieve selective cancellation of interfering peaks (SCIP).
    In this paper, data are presented concerning the utility of the conductivity detector in the qualitative and quanti- tative analyses of organochlorine pesticides in the pres- ence of PCB’s.
    EXPERIMENTAL SECTION
    Materials. All organochlorine pesticides and Aroclors were analytical standards obtained from the Perrine Pri- mate Laboratory, E.P.A., Perrine, Fla. They were used as received.
    Gas Chromatograph. A Micro-Tek (Tracor. Inc.) Model 220 gas chromatograph equipped with a Coulson conductivity detector, Vycor glass inserts at the injection port for off-column injection, and U-shaped 6 ft X in. 0.d. pyrex glass columns were used. The column packings (supplied by Perrine Primate Laboratory) were 1.5% OV- 17/1.95% QF-1 on 60-80 Chromosorb W HP. Carrier gas flow rate was 70 ml/min.
    Operating Parameters. The operating parameters of the Coulson conductivity detector for gc in the noncataly- tic reductive mode are as follows: conductivity bridge voltage, 30 V; conductivity bridge attenuation, 1; furnace (reactor) temperature, 660-840″; transfer block tempera- ture, 250″; hydrogen flow rate through reactor, 40 ml/min; nitrogen flow rate through reactor, 100 ml/min; gas chro- matograph column temperature, 200″;sample size, 5 pl.
    All operating parameters, except for the reactor temper- ature, were kept constant for all the experiments.
    RESULTS AND DISCUSSION
    The Coulson electrolytic conductivity detector gives sharp symmetric peaks much like those observed for other detector systems. The magnitude of detector response is a function of the conductivity of the species being analyzed.
    Organochlorine compounds can be noncatalytically re- duced at high temperatures to hydrogen chloride and methane with hydrogen in a quartz tube (the reactor). Hydrogen chloride elicits excellent detector response, while methane is inert to the detector. By varying the re- actor temperature and/or reactor gas ratios or flow rate, a variety of pyrolytic products, often nonconducting, may be obtained (Tracor, Inc., 1971). Thus, in a mixture of or- ganochlorine compounds, some could be rendered unde- tectable while the rest are still readily detectable by ap- propriate manipulation of operating parameters.
    A good linear relationship was observed for peak height us. pesticide concentration at both 830″ and 660″ for B- BHC, oxychlordane, heptachlor epoxide, p,p’-DDE, o p DDT, p,p’-DDD, p,p’-DDT, and Mirex. Typical results are shown in Figures 1 and 2. Furthermore, the detector
    ORGANOCHLORINE PES’TICIDES
    J.Agr.FoodChem.,Vol.21,No.6,1973 1090

    The Reynolds article (probably inaccessible) is http://www.springerlink.com/content/k283q633767n1874/

    The PCB’s and related compounds (although in the rest of this paper reference will be made to the PCB’s only, the other related compounds are also quite important) have very numerous and impor- tant industrial uses, but are not used as pesticides. Because of their similarities in structure and properties to the DDT pesti- cide group, the PCB’s, if present, are carried through the usual pestieide extraction and screening procedures, and since they possess electron absorbing properties, will interfere with gas liquid chromatographic electron capture (GLC-EC) analysis of the organochlorine compounds.

    1995 (slow to load)
    http://nwql.usgs.gov/pubs/OFR/OFR-95-140.pdf
    USGS Open-File Report 95-140

    Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory — Determination of Organochlonine Pesticides and Polychlorinated Biphenyls in Bottom Sediment by Dual Capillary-Column Gas Chromatography with Electron-Capture Detection
    William T. Foreman, Brooke F. Connor, Edward T. Furlong, Deborah G. Vaught, and Leslie Merten
    1995
    A method for the determination of 30 individual organochlorine pesticides, total toxaphene, and total polychlorinated biphenyls (PCBs) in aquatic bottom sediment is described and laboratory performance data are provided. The method was developed in support of the U.S. Geological Survey’s National Water-Quality Assessment program and is based on conventional Soxhlet extraction using dichloromethane. Two aliquots of the sample extract are quantitatively injected onto a styrene-divinylbenzene gel permeation column and eluted with dichloromethane. This gel permeation chromatography step removes inorganic sulfur and large naturally occurring molecules from the sediment extract. The first aliquot is analyzed for semivolatile organic compounds by gas chromatography with mass spectrometric detection. The second aliquot is further split into two fractions by combined alumina/silica adsorption chromatography prior to the determination of the organochlorine pesticides and PCBs by dual capillary-column gas chromatography with electron-capture detection (GC/ECD). This report completely describes and is limited to the determination of the organochlorine pesticides and PCBs by GC/ECD. Current (February 1995) data-reporting limits have been set at 1 to 5 micrograms per kilogram for 30 chlorinated pesticides, 50 micrograms per kilogram for total PCBs and 200 micrograms per kilogram for toxaphene.

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  9. Ed Darrell says:

    Nice finds, every one of them.

    Good heavens! How do you do this stuff? How do you find all these strange publications?

    Like

  10. j a higginbotham says:

    mid page 34 to 35
    http://www.dioxinnz.com/pdf-scientific-other/Dissertation-Joe-Conley-II-Princeton-Uni-PHD.pdf

    referencess:
    DDT, scientists, citizens, and public policy, Volume 2
    Thomas R. Dunlap
    University of Wisconsin–Madison, 1975 – Science – 740 pages thesis
    unavailable online at:
    http://hdl.handle.net/2027/wu.89098572688

    background
    http://www.law.wisc.edu/alumni/gargoyle/archive/16_2/gargoyle_16_2_2.pdf
    http://www.wisconsincnra.org/imagesmain/cnraandddt.pdf
    http://www.marathon.uwc.edu/geography/350/DDT-hearing.htm

    ddt and pcb’s can be confused depending on technique but also can be distinguished

    Like

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