Enst 403/Envr 403: Spring 2009

1. Enst 403/Envr 403:Spring 2009 • Tues, Thurs room 11AM-12:15AM • Location: Dey Hall room 201 Call number 36019, Section 001 • http://www.unc.edu/courses/2009fall/enst/403/001/ • Richard Kamens; 966 5452 • kamens@unc.edu • http://airsite.unc.edu/~kamens/

2. Textbook • "Environmental Chemistry by Colin Beard and Michael Cann, ISBN 0-7167-4877-0, publishers W.H. Freeman and Company, New York, 652 pages, 2005

3. Who is Richard Kamens • Professor of Atmospheric chemistry and teach graduate classes in Environmental chemistry • Direct a smog chamber research gorup • Focus on aerosol formation in the atmosphere • Direct a student exchange program between UNC and Thai Universities

4. Killer Particles

5. On smoggy days in LA, Atlanta, Beijing and other major cities ~50 - 80% of FINE particle organic carbon comes from atmospheric reactions. • Atmospherically aged aerosols appear to be more toxic than freshly emitted particles. • A strong need for predictive aerosol models that can simulate complex atmospheric processing?

6. Terpenes Aromatics Development of chemical mechanisms from organics that produce particles:

7. Thermodynamic Equilibrium Cgas +surf Cpart Temperature Chemical nature of gas Humidity and particle Link the phases that toxics exist in Trace toxic gas particle

9. O3 NO NO2 NOy Predict organic particle formation in the presence of complex urban atmospheres 25 20 15 3 g/m m 8:00 10:24 12:48 15:12 17:36

10. Aerosol Model and data from particles generated from aromatics and O3 and NOx in sunlight 1ppmC o-xylene 1ppmC toluene

11. Field site director for a UNC-Thai exchange • Since 2001, UNC undergraduates (CEP)participated in a 6+ month experience in Thailand that begins at the end of May and finishes in late December. • Small groups of UNC students come together with Thai students to study and work on a research project at Thai universities. • Thai students come back with UNC students for a semester at UNC.

12. Impact of Bio-fuels Use on Photochemical Smog • The widespread use of gasohol and bio-diesel in Bangkok will most likely lead to an increase in ground level ozone. • Bio-fuel use will benefit the Thai economy. • Bio-fuels can supply at most 10% of the Thai petroleum needs.

16. Introduction to Environmental Chemistry • Environmental chemistry may be defined as "the study of sources, reactions, transport, effects, and fates of chemical species in water, soil, and air environments, and the effects of technology thereon.” Manahan, 1994

17. Class objectives: • Highlight some important areas in environmental chemistry • present some of the common techniques that environmental chemists use to quantify process that occur in the environment • It is assumed that everyone has courses in calculus and general chemistry.

18. Class objectives: • We will cover general topics: Global warming, Strat. O3, aerosols, photochemical smog, acid rain, etc. • Develop relationships will be used to help quantify equilibrium and kinetic processes

19. Thermodynamics • ui = uo1 +RT ln pi/p*iL • fi = i Xipi*pure liquid • RT lnfi hx /fiopure liq = RT lnfi H2O/fiopure liqfihx = fi H2O • ln Kp = a 1/T+b

20. Vapor pressure How to calculate boiling points

21. Vapor pressure and Henry’s law sat P sat sat *    i K P V iL iw sat iaw iw C iw Solubility and activity coefficients Octanol-water partitioning coefficients

22. Additional Principles • Organic Acid-bases and LFERs • diffusion • chemical spills and mass transfer • Organic reactions in the environment • Solid- liquid interactions • photochemistry

23. Homework, quizzes, exams • To insure that most of us stay reasonably current with the lectures and readings, an option is to have 8-10 unannounced quizzes throughout the semester. • They will take ~10 minutes. Quizzes will count 10% of your grade.

24. Another option is a set of short questions to be answered and handed in before most lectures (20% of your grade)—your choice!

25. There will be a homework problem set associated with each lecture. These are due one week after the completion of the chapter or lecture series. • These problem sets should take between 1 and 3 hrs.

26. Some of these could appear on exams • There will be two exams

27. Important Environmental Issues • Global warming and stratospheric ozone depletion • Concentration of environmental pollutants at the poles; pesticides in foods, etc. • Buildup of environmental chemicals in the oceans; contamination of soil and ground water • Particle exposure, photochemical oxidant exposure, acid deposition • Energy shortages

28. Why the interest? There are more than 70,000 100, 000 synthetic chemicals that are in daily use: solvents components of detergents dyes and varnishes additives in plastics and textiles chemicals used for construction antifouling agents herbicides, insecticides,fungicides pharmaceuticals

29. Some examples of environmental chemicals Polynuclear Aromatic HC (PAHs) Dioxins PCBs CFCs DDT O3, NO2, aerosols, SO2

30. PAHs Formed from small ethylene radicals “building blocks” produced when carbon based fuels are burned Sources are all types of burning in ChiangMai, Thailand:a) 2-stroke motorcycle engines b) cars- light diesels c) open burning d) barbecued meat??

31. Combustion Formation of PAH Badger and Spotswood 1960

32. Some PAH structures fluoranthene naphthalene anthracene benz(a)anthracene phenanthrene benzo(a)pyrene [BaP]

33. PAHs Naphthalene, phenanthrene and anthracene are found in the gas phase pyrene and fluoranthene are in both the gas and particle phase BaA and BaP are mostly on the particles, Why???

34. PAHs Metabolized to epoxides which are carcinogenic; O PAH are indirect acting mutagens in bacterial mutagenicity tests (Ames-TA98+s9) methyl PAHs are often more biologically active than PAHs

35. Carcinogenic tests with PAHs Professor Gernot Grimmer extracted different types of smoke particles He then took the extract and applied it to mouse skin and implanted it into rat lungs How did he obtain extracts? How did he fractionate his extracts??

36. Extraction by soxhlet extraction starts with solvent (MeCl2) in a flask

37. Hot solvent fills this chamber and bathes the filter Heat

38. The solvent in the filter chamber then drains back into the heated flask withchemicalsfrom the particleson the filter Heat

39. The organic liquid in the soxhlet flask can be concentrated by evaporation by a dry nitrogen stream or rotary evaporation • the extract can then be fractionated into different polarity compound groups

40. Professor Grimmer fractionated the exhaust extracts HPLC uv orfluorescencedetector Total Total PAH 2&3 rings PAHs>3 rings Total-PAHs

41. What did Grimmer see when exposed rats and mice to the different fractions? • skin painted mice • implanted rat lungs

43. Analysis of reaction products • soxhlet extraction for 3 hours • blow up with dry gentle flow of nitrogen to about 0.5 to 1 ml • evaporation to about 0.5 to 1 ml • 1 to 2 ul injected directly to GC-MS (EI and CI) • The remainder solution: derivatization

44. Chlorinated dibenzo dioxins and Furans These are some of the most toxic organics in the environment - LD50 Created by burning organics which have chlorine; incineration is a big source of atmospheric dioxins and furans bleaching in making paper is another source

45. Combustion Formation of Dioxins from Polychlorinated phenol O H Clx . OH Clx Flame . O O H + Polychlorinated Phenol C l y O + OH O Cly Cly Clx O Clx O H Chlorinated dibenzo dioxin Shaub & Tsang, ES&T 1983.

46. They have the following general structures O Cl x O Cl y chlorinated dioxin

47. Cl x Cl y They have the following general structures O Cl x O Cl y chlorinated dioxin O chlorinated furan

48. O Cl Cl Cl Cl O More than 200 different structures are possible The most toxic is either the 2,3,7,8 tetrachlorodibeno dioxin or furan

49. These types of compounds produce toxic enzymes: arylhydrocarbon hydroxylase and 7-ethoxyresorufin deethylase At low concentrations they may behave as environmental estrogens

50. Environmentally, they are unreactive and can be transported long distances They did not start to show up in the environment until the 1920s when there was a big increase in the production of chloro-organics (Professor Ron Hites, and students)