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Staff: Staff: Techs: Grad. Students: P. Lyon H. Tong D. Lippstreu J. O. Lay

Lecture by Michael L. Gross, MOC 4:30 pm. “Toxic Clouds”: Chapter 1 in the Story of Tetrachlorodibenzodioxin, Its Analysis and Its Accumulation in the Environment and in Humans. Staff: Staff: Techs: Grad. Students: P. Lyon H. Tong D. Lippstreu J. O. Lay T. Sun Z. Cai N. Kangas E. Chess

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Staff: Staff: Techs: Grad. Students: P. Lyon H. Tong D. Lippstreu J. O. Lay

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  1. Lecture by Michael L. Gross, MOC 4:30 pm “Toxic Clouds”: Chapter 1 in the Story of Tetrachlorodibenzodioxin, Its Analysis and Its Accumulation in the Environment and in Humans Staff: Staff: Techs: Grad. Students: P. Lyon H. Tong D. Lippstreu J. O. Lay T. Sun Z. Cai N. Kangas E. Chess D. Giblin S. Arghestani S. Monson Support: L. Weerasinghe J. Meehan NSF, EPA, VA

  2. Abstract Introduction A “hot” subject in environmental chemistry thirty years ago was the possible accumulation of dioxins, mainly 2,3,7,8-TCDD, in the environment. Given its high toxicity and the scattered but frightening evidence that it was accumulating from use of certain chlorinated herbicides, the popular press focused on three issues: 1. the heavy use of TCDD-containing herbicides (Agent Orange) in the Vietnam conflict, 2. the Seveso, Italy, explosion in 1976 of a chemical plant, resulting in the highest known exposure to TCDD in residential populations, and 3) the efforts by the US EPA to ban 2,4,5-trichlorophenoxyacetic acid and related herbicides. A later, but still, controversial addition was a theory by Dow-Chemical scientists that the major source of dioxins was combustion and not herbicides. Methods The first putative detections of TCDD that raised public concern were at Harvard with a high resolving power mass spectrometry and direct probe introductions of human fluid extracts. This method gave way to packed column GC/MS with selected ion monitoring at 10,000 resolving power. In collaboration with US EPA scientists, we validated this method in animal fat and later in human milk. To my knowledge, this was the first validation of a part-per-trillion analysis of an organic compound. The driving force for this work was the intention of the US EPA to have highly certain data on TCDD accumulation to support its position to ban 2,4,5-trichlorophenoxyacetic acid and silvex, two herbicides that contained low levels of TCDD. Discussion The validation using high resolving power sector mass spectrometry was successful down to a few ppt in animal fats, and, later, to a few tenths of a ppt in human milk. The USEPA General Counsel’s office deemed the method to meet legal standards, permitting pursuit of herbicide banning. We applied the method to human milk samples taken from women from forest areas of Oregon where 2,4,5-trichlorophenoxy-based herbicides were used in forestry management. The women apparently were suffering an unusually high tendency for miscarriage, attributable to the teratogenic properties of TCDD. Although no convincing detections could be made in milk, the methodology did demonstrate the accumulation of TCDD in Air Force personnel who handled Agent Orange in Viet Nam. This discovery alarmed veterans throughout the US because many returning soldiers suffered unknown disorders that could be attributed to TCDD exposure. Extensive sequel studies at the CDC confirmed the detections, revealing levels in ppt range. Although questions still remain whether about health impact, mass spectrometry had placed limits on exposure types that lead to TCDD accumulation in humans. As the chapter ended, the production of dioxins in combustion had been established, but evidence from our and, more convincingly, from Hites’ laboratory showed that they don’t arise from general combustion but from that of waste. Although other methods emerged (e.g., electron-capture CI, which Hites and Budde compared), the method used worldwide today is still GC/HRMS. Testimony Environmental protection was an early driver of MS development. The hallmark of environmental analysis has remained data quality. Data are scrutinized by scientists, regulators, lawyers, and the public, affording an interesting synergism between science and public policy. The efforts of Budde and Hites demonstrate clearly their leadership and commitment to the highest quality chemical analysis.

  3. Tong, H. Y.; Giblin, D. E.; Lapp, R. L.; Monson, S. J.; Gross, M. L.. Mass profile monitoring in trace analysis by GC/MS. Anal.Chem. (1991), 63,1772-80. Ion from PCB Interference Int. Std. (TCDD-37Cl4 • Advantages of Mass Profile Monitoring (compared to peak top monitoring: • Accurate m/z with highest certainty • Characterization of interferences of similar accurate m/z • Removal of interferences in quantification RP = 10,000

  4. Advantage of Peak-shape monitoring Int Std Analysis of adipose from monkey on diet contaminated with 25 ppt 2378 TCDD. Chromatographic pks A & B could be due to TCDD isomers, but component have incorrect centroids and incorrect accurate m/z’s.

  5. Validation-Stage 1 Gross M L; Sun T; Lyon P A; Wojinski S F; Hilker D R; Dupuy A E Jr; Heath R G Method validation for the determination of TCDD at the low parts-per-trillion level. Anal.Chem. (1981),53,1902-6. Packed Column GC/HRMS

  6. Validation—Stage 2 Heath, R. G.; Harless, R. L.; Gross, M. L.; Lyon, P. A.; Dupuy, A. E., Jr.; McDaniel, D. D. Determination of 2,3,7,8-TCDD in human milk, at the 0.1-10 parts-per-trillion level: method validation and survey results. Anal.Chem. (1986), 58, 463-8. Packed-Column GC/HRMS Capillary Column GC/HRMS

  7. Typical Data Int Std: C-13 labeled TCDD Monoisotopic and A + 2 Mol Ions (ratio = 0.78:1.0

  8. Human Exposure: Agent Orange Gross, M.L.; Lay, J.O., Jr.; Lyon, P.A.; Lippstreu, D.; Kangas, N.; Harless, R.L.; Taylor, S.E.; Dupuy, A.E., Jr. TCDD levels in adipose tissue of Vietnam veterans. Environ. Res. (1984), 33, 261-8. Agent Orange: a defoliant containing 24-D and 245-T and ppm 2378-TCDD

  9. Vietnam Veteran Exposure

  10. Sequel Studies of Vietnam Veterans Schecter, A.; Constable, J.D.; Arghestani, S.; Tong, H.; Gross, M.L. Elevated levels of 2,3,7,8-TCDD in adipose tissue of certain U.S. veterans of the Vietnam War. Chemosphere (1987),16,1997-2002. Schecter, A.; Constable, J.D.; Bangert, J.V.; Tong, H.; Arghestani, S.; Monson, S.; Gross, M. Elevated body burdens of 2,3,7,8-TCDD in adipose tissue of United States Vietnam veterans. Chemosphere (1989),18, 431-8. • Results: • 22 parts per trillion in 12 Ranch handers • 42 parts per trillion in 10 “heavily exposed veterans” (Kahn, Rappe, et al., J.Am.Med.Assoc, 259, 1661 (1988) • 3 “heavily exposed” veterans had between 20-99 parts per trillion in adipose (1984 work)

  11. 2378-TCDD Levels in Vietnam Veterans—Cap GC/HRMS

  12. Extensive Studies of Vietnam Vets by CDC Michalek, J.E.; Pirkle, J.L.; Needham, L.L.; Patterson, D.G., Jr.; Caudill, S.P.; Tripathi, R.C.; Mocarelli, P. Pharmacokinetics of 2,3,7,8-TCDD in Seveso adults and veterans of operation Ranch Hand. J. Expos. Anal. Environ. Epid. (2002), 12, 44-53. Mean Rate of Elimination: 0.0931 year-1 (t1/2 = 7.4 y)

  13. Exposure of Vietnamese to Agent Orange Schecter, Arnold; Tong, H. Y.; Monson, S. J.; Gross, M. L.; Constable, J. Adipose tissue levels of 2,3,7,8-TCDD in Vietnamese adults living in Vietnam, 1984-87. Chemosphere (1989),18,1057-62. South Vietnam: Median: 8.8 parts-per-trillion (lipid basis) Range 1.2-26 parts-per-trillion (lipid basis) 1 of 14 person had nd levels (dl = 3 ppt) Mean of positives: 10 parts-per trillion (lipid basis) Schecter, A.J.; Ryan, J.J.; Gross, M.; Weerasinghe, N.C.A.; Constable, J.D. Chlorinated dioxins and dibenzofurans in human tissues from Vietnam, 1983-84. Chlorinated Dioxins Dibenzofurans Perspect. (1986), 35-50. North and South Vietnam: 7 human adipose tissue specimens from Hanoi hospitals contain nd amount of 2378-TCDD (dl = 2 ppt) 10 of 13 samples from Saigon hospitals contain 2378-TCDD at 22 parts-per-trillion, mean.

  14. Exposure of US Agricultural Worker to TCDD Tong, H. Y.; Monson, S. J.; Gross, M. L.; Powell, B. M. Elevated levels of 2,3,7,8-TCDD in tissue of an agricultural sprayer of herbicides: a single case study. Chemosphere (1989),18, 469-76. • Results: • 74 parts-per-trillion in adipose tissue (5 y after last exposure) • 8 parts-per-billion in archived 2,4,5-T samples • Exposure: via hand spraying and tractor-spraying of herbicide (150 gal/year over a period of 14 years). Reported inhalation and dermal exposure to herbicide. • Health: Assorted health problems including three episodes of cancer. “. . . no causal relationship between the exposure and health. . .

  15. Transmittal of TCDD from Mother to Offspring Bowman, R. E.; Schantz, S. L.; Weerasinghe, N. C. A.; Gross, M. L.; Barsotti, D. A. Chronic dietary intake of 2,3,7,8-TCDD at 5 or 25 parts per trillion in the monkey: TCDD kinetics and dose-effect estimate of reproductive toxicity. Chemosphere (1989),18, 243-52. • t1/2 = 391± 88 days; • Offspring accumulated in fat 4.3 times of that in mothers’ fat.

  16. Dioxin Contamination in Newark Bay/NY Harbor Bopp, R.F.; Gross, M.L.; Tong, H.; Simpson, H.J.; Monson, S.J.; Deck, B.L.; Moser, F.C. A major incident of dioxin contamination: sediments of New Jersey estuaries. Environ.Sci.Technol.(1991), 25, 951-6. Passaic River Diamond Alkali Plant Hudson River Manhattan Newark Bay • Core samples dated by radioactive dating • 7Be (t1/2 = 53 days, for recent dating) and 137Cs (from atm testing of nuclear weapons for post 1954 dating) • Core samples analyzed for 2378-TCDD and OCDD by HRGC/HRMS

  17. Levels of 2378-TCDD (OCDD) in Dated Sediments in NY/NJ Harbor

  18. Fall: ND (10 ppt) Muscle; 130 ppt Pancreas Spring: ND (10) 70 ppt Fall: ND (7 ppt) Muscle; 90 ppt Pancreas Spring: ND (10) 50 ppt Fall: ND (5 ppt) Muscle; 45 ppt Pancreas Spring: ND (5) 80 ppt 2378 TCDD Levels in Blue Crab Muscle and Pancreas Fall: 42 ppt Muscle; 820 ppt Pancreas Spring: 30 ppt 520 ppt Cai, Z.; Ramanujam, V.M.S.; Gross, M.L.; Cristini, A.; Tucker, R.K. Levels of Polychlorodibenzo-p-dioxins and Dibenzofurans in Crab Tissues from the Newark/Raritan Bay System. Environ. Sci. Technol. (1994), 28, 1528-34.

  19. Potential Exposure of New Yorkers to Dioxin --New Jersey Dept of Environ Protection, Hauge P M; Belton T J; Ruppel B E; Lockwood K; Mueller R T 2,3,7,8-TCDD and TCDF in blue crabs and lobsters from the Hudson-Raritan estuary and the New York Bight. Bull. Environ. Contamin.Tox. (1994), 52, 734-41. n

  20. Trace Chemistries of Fire: Hypothesis by Dow Chemical Bumb, R. R.; Crummett, W. B.; Cutie, S. S.; Gledhill, J. R.; Hummel, R. H.; Kagel, R. O.; Lamparski, L. L.; Luoma, E. V.; Miller, D. L.; et al. Trace chemistries of fire: a source of chlorinated dioxins. Science (1980), 210, 385-90.

  21. Is TCDD produced in ALL combustion? Kimble, B. J.; Gross, M. L.. Tetrachlorodibenzo-p- dioxin quantitation in stack-collected coal fly ash. Science (1980), 207, 59-61. 470 pg of internal std 47 pg of native 2378 TCDD Analysis of 32% of extract of xx g of fly ash Analysis of 28% of extract at x10 gain on detector. Interference is from PCB Repeat analysis of 32% of extract of xx g of fly ash

  22. Combustion is major source of some dioxins

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