Airborne Contaminants Lab

1. Airborne Contaminants Lab

5. Topics • Overview of workplace health and its regulation • Particulates and microscopy • Gases and vapors • Monitoring • Real time • Noise

6. Format • Lecture with break • Break • Hands-on, with Sheila M Simmons • Environmental Health, Safety, and Risk Management • http://www.uaf.edu/safety/

7. Practical Application • The terms • “Environmental Engineering” • “Environmental work • Often extend to analyzing the workplace environment for contaminants • hence offering opinions on human health • firms often practice in this area.

8. Alphabet Soup • EPA • OSHA • NIOSH • AIHA • ACGIH

9. Alphabet Soup • OSHA, Occupational Safety and Health Administration • NIOSH, National Institute of Occupational Safety and Health • AIHA, American Industrial Hygiene Association • ACGIH, American Conference of Governmental Industrial Hygienists.

10. OSHA and NIOSH • Created in 1970’s by same act of congress • MSHA was earlier, • OSHA • Law enforcement • Department of Labor • NIOSH • Science • Center for Disease Control in PHS.

11. AIHA and ACGIH • Industrial hygiene = science of workplace health • AIHA accredits laboratories • ACGIH produces TLV’s • “safe values”

12. Occupational Standards • OSHA, PELs • (CFR, code of federal regulations, on line) • PELs • ACGIH, TLVs • NIOSH, RELs • DFK, MAKs

13. TLVs • Of the approximately 450 standards • 15% have human or otherwise well tested • 25% have some animal testing • 60% Based on “analogy,” “supposed,” or “traditional.”

14. OSHA • OSHA main site OSHA • 1910 Subpart Z • 1910.1000 • History of Tables • ANSI list • lawsuits

15. Contaminant Particulates • Asbestos • Quartz • Dust

16. Asbestos is useful • Asbestos used since ancient times • Fireproof • WW II ship building • Insulation • 1950’s Schools • Sound proofing, • Many materials • Strength of fibers, chemical resistant

17. Asbestos kills • About 10,000 persons die each year from asbestos related disease • 1,000 from mesothelioma • 4,000 from asbestosis • 5,000 from lung cancer • (correlated with cigarette smoking) • 20 to 40 year latency period • Airborne fibers, not parent material

18. Asbestos is regulated • OSHA regulates workplace exposures • EPA regulates schools • EPA regulates disposal process

19. Insert SiO4: Asbestos Minerals • Asbestos is a commercial term • Polysilicate minerals

20. 10 u +/-

21. lisa m applebee: structure Amphiboles • Amosite (Mg, Fe) • Actinolite (Ca, Mg, Fe) • Anthophyllite (Mg, Fe) • Crocidolite (Na, Fe+++, Fe++) • Tremolite (Ca, Mg)

22. Serpentine • Chrysotile (Mg)

23. Respiratory Tract • Anatomy • Physiology • Notes on the asbestos diseases

24. Asbestosis • Fibrotic lung disease • Lungs fill with scar tissue • restrictive lung disease, stiff • oxygen transport reduced • breathing labored

25. Gallery • Boston University School of Public Health • Breath Taken: The Landscape & Biography of asbestos • http://www/busph.bu.edu/Gallery

26. Normal Lung:

27. Honeycombing

28. Asbesosis

29. Asbestos, clubbing of fingers

30. Hairdresser, combed from hair

31. Mesothelioma • Cancer of the lining of the abdominal cavity • Or thoracic cavity • Fatal

32. childhood exposure father worked in plant and died of asbestosis note tumor on right side, fills with fluid

33. Mesothelioma is a rare cancer • 2 deaths per million populations • But in a study of asbestos insulation workers there were 175 deaths from mesothelioma.

34. Lung Cancer • 32 of 41 studies indicated statistically significant increase in lung cancer of asbestos workers • Non-smokers were 5-fold higher than non-exposed • Smoking asbestos workers were much higher 50- to 90-fold

38. Toxicology, Fiber type • Some studies indicate chrysotile can cause mesothelioma • Most indicate amphiboles, especially crocidolite • Some authors have concluded amphiboles are 100 times more potent than chrysotile in inducing mesothelioma.

43. particle fiber

44. Clearance and fiber size • Residents of cities breath several hundred grams of particles over a lifetime • Only a few grams at autopsy • Most are cleared from lung • Sorting in the airways by aerodynamic diameter • Thin fibers penetrate much deeper than round particles of similar diameter

45. Clearance mechanism by location of deposition • Nasal clearance: • in from of ciliated, by sneezing or blowing • further back swept down and swallowed • Tracheobronchial: cleared via cilia • mucociliary escalator • Alveolar • macrophage

46. Robins pg. 757 Macrophages • Digest particles • Carry towards ciliated airway • Can wind up in lymph nodes and elsewhere • especially is “surface” route is overwhelmed

47. Macrophage

48. Macrophage

49. Clearance • Fibers less than 1 micron cleared half-life of 10 days • Fibers longer than 16 micron, half-life over 100 days • Maximum fiber length of one macrophage about 16-17 microns

50. Disease vs. fiber length • Animal studies • Dust rich in f < 5  less lung cancer • Dust rich in f > 5  more lung cancer • Asbestosis associated f > 2  • Lung cancer f > 5  • Mesothelioma f > 10 