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Mercury Awareness and Safety

Bureau of Workers’ Comp PA Training for Health & Safety (PATHS). Mercury Awareness and Safety. PPT-056-01. 1. Mercury (Hg) and variations Properties Historic uses In-home uses Amalgams Dental use Health effects Hg poisoning Respirator recommendations Response safety

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Mercury Awareness and Safety

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  1. Bureau of Workers’ Comp PA Training for Health & Safety (PATHS) Mercury Awareness and Safety PPT-056-01 1

  2. Mercury (Hg) and variations • Properties • Historic uses • In-home uses • Amalgams • Dental use • Health effects • Hg poisoning • Respirator recommendations • Response safety • Bibliography Topics PPT-056-01 2

  3. Atomic number 80 • Also known as quicksilver • Only metal that is liquid at standard conditions for temperature and pressure • Only other element that is liquid under these conditions is bromine Mercury Awareness and Safety PPT-056-01 3

  4. Mercury occurs as deposits; mostly as cinnabar, known as mercuric sulfide. • Cinnabar: Highly toxic by ingestion or dust inhalation • Elemental Hg can be produced by heating mercury-containing ores and condensing the vapor Mercury (Hg) PPT-056-01 4

  5. Mercury (Element) Hg • Organic (Methylmercury & Phenylmercury) • Inorganic Compounds known as Mercurial salts: • Mercury(I) chloride (mercurous chloride) • a.k.a. Calomel • Mercury(II) chloride (mercuric chloride) • David Aldridge, his own work with permission Three (3) Classes of Hg PPT-056-01 5

  6. From Table Z-1: Limits for Air Contaminants 8-hr TWA SubstanceCAS No. mg/m3 Mercury (aryl and inorganic)(as Hg) 7439-97-6 OSHA PEL: C 0.1 Mercury (organo) alkyl compounds (as Hg) 7439-97-6 OSHA PEL: TWA 0.01 Mercury (vapor)(as Hg) 7439-97-6 OSHA PEL: TWA 0.05 [skin] 29 CFR 1910.1000, Subpart Z PPT-056-01 6

  7. ReactionMaterial Vigorous Mixtures of sodium carbide, aluminum, lead, iron Violent/explosive Chlorine dioxide, lithium, rubidium Reactive with Azides, ammonia, ethylene oxide, and other materials Incompatibilities PPT-056-01 7

  8. Hg CompoundUsed to make • Mercuric sulfate acetaldehye • vinyl chloride • vinyl acetate • Mercuric chloride disinfectant • Metallic Hg is poisonous • Heavy metals alter enzymatic and protein action and can lead to death.* • *Eugene Meyer, Chemistry of Hazardous Materials, Prentice-Hall Inc., 1977 Hg Uses PPT-056-01 8

  9. Mercury compounds [except (organo) alkyls] (as Hg) • Formula: Hg (metal) • CAS# 7439-97-6 • IDLH: 10 mg/m3 (as Hg) • DOT: 2809 • ERG Guide page 172 (metal) • OSHA PEL: Ceiling 0.1 mg/m3 • Synonyms/Trade names: Mercury metal - Colloidal mercury, Metallic mercury, Quicksilver; other synonyms vary depending upon specific inorganic and aryl Hg compounds NIOSH Pocket Guide Information PPT-056-01 9

  10. MW: 200.6 • Insoluble • Flash point: NA • IP: ? • Specific Gravity: 13.6 (metal) • UEL: NA • LEL: NA NIOSH Pocket Guide Information PPT-056-01 10

  11. Specific Gravity: • Mercury is 13.6 times heavier than water • This density enables it to be used in water level gauges measuring inches of Mercury to feet of water; where each inch of Mercury read will support a column of water 1.13 feet high. Properties of Hg Note Mercury’s ability to support heavy objects PPT-056-01 11

  12. Properties of Hg • Allows us to determine atmospheric pressure PPT-056-01 12

  13. Fur removal from pelts to make hats in the mid-1700s to mid-1800s • Vapors from process were very toxic • Mercury poisoning was said to make one “mad as a hatter” • Also used in mining to separate gold and silver from ore to create an amalgam for recovery Historic Uses PPT-056-01 13

  14. 1800s • Treat depression • Toothaches • 1900s • Laxatives • Teething powders • Mercurochrome Historic Uses PPT-056-01 14

  15. Through catalytic reactions, Hg is used to make polymers, chlorine and caustic soda, as well as to extract gold from ore Historic Uses PPT-056-01 15

  16. Fishing lures • Lighthouse lenses • Fire detectors • Power plants: fossil and nuclear • Separating chlorine and sodium from brine • Thermometers Historic Uses PPT-056-01 16

  17. Precautions are required due to the use of Mercury-containing materials in each household • Other uses of Hg should instill safety considerations In-Home Uses PPT-056-01 17

  18. Mercury switches to control thermostats in our homes In-Home Uses PPT-056-01 18

  19. Wood preservative • Making mirrors • Herbicides • Antiseptics • Antidepressants • Mercury battery for hearing aids • Cosmetics In-Home Uses PPT-056-01 19

  20. Compact Fluorescent Lamp (CFL) • More in use: less power to generate more light; last longer than conventional bulbs • Injection of Mercury via broken glass may occur Fluorescent Lamp PPT-056-01 20

  21. Breakage from Hg lamps may appear insignificant and easy to remedy, but you should exercise due care and maximize safety when cleaning this up Mercury Lamps PPT-056-01 21

  22. Most toxic forms for Mercury • Organic compounds: • Dimethyl mercury • Methyl mercury • Inorganic compounds (such as cinnabar) highly toxic by ingestion and inhalation Hg Forms PPT-056-01 22

  23. Hg dissolves to form amalgams with gold, zinc and other metals • Hg reacts with aluminum to form a Mercury/aluminum amalgam • This reacts with air resulting in aluminum oxide; corrodes aluminum, not allowed on aircraft because it may react with aircraft metal, thereby weakening it Amalgams PPT-056-01 23

  24. Dental Use • Dental amalgam contains Mercury • Professionals agree fillings may release Mercury but opinions on health risks are diverse PPT-056-01 24

  25. Inhalation • Primary route for elemental Mercury • 75 percent to 80 percent is absorbed by lungs • Vapors are heavier than air (vapor density: 6.9) • Skin or Eye Contact • Absorbed slowly through skin • Causes irritation to skin and eyes and possibly contact dermatitis • Ingestion • Methyl mercury completely absorbed and not readily eliminated Routes of Exposure PPT-056-01 25

  26. Inhalation of vapor; major exposure route • Symptoms may include corrosive bronchitis progressing to pulmonary edema or fibrosis • Mercury can cross the blood, brain and placental barriers, posing an increased risk to children • Agency for Toxic Substances and Disease Registry, Medical Management Guidelines for Mercury, found at http://www.atsdr.cdc.gov/MMG/MMG.asp?id=106&tid=24 Health Effects PPT-056-01 26

  27. Understanding the food chain allows us to understand how we might internalize Mercury • State fishing laws are specific regarding the amount of fish which may be eaten on a daily basis after waterway studies have been made Food Chain Consequences PPT-056-01 27

  28. System:Symptoms: Respiratory Cough, sore throat, shortness of breath Gastrointestinal Metallic taste, nausea, vomiting, diarrhea, abdominal pain Central Nervous Headache, weakness, visual System disturbances Acute Health Effects PPT-056-01 28

  29. Mercury may accumulate in the body, resulting in permanent damage and changes to: • Kidneys • Nervous system • Muscles Chronic Exposure PPT-056-01 29

  30. Atmospheric Hg in U.S. 1998 • Due to air pollution and other releases of Hg into the atmosphere PPT-056-01 30

  31. Mercury Poisoning may result from: • Exposure to water-soluble forms of Mercury, i.e. Mercuric chloride or Methylmercury • Inhalation of Mercury vapor or eating contaminated seafood • Symptoms of Hg poisoning include: • Mild gastritis to severe pain with vomiting • Convulsions and numbness in mouth and limbs • Visual field constriction • Speaking difficulty Mercury Poisoning PPT-056-01 31

  32. In 1953, poisoning occurred in Japan when industrial waste was discharged into Minamata Bay; the waste contained Methyl mercury salts • Aquatic microorganisms can convert mercury salts into methylated compounds (a methyl group attaches to Mercury atoms); these are easily absorbed into animal tissues • Minamataresidents ate the fish containing Mercury Mercury Poisoning PPT-056-01 32

  33. In the 1960’s and 1970’s in Iraq, wheat treated with Methyl mercury as a preservative due to being seed grain was fed to animals and consumed by people • Resulted in neurological symptoms: • Speech difficulties • Narrowing of visual field • Hearing impairment • Blindness • Death Mercury Poisoning PPT-056-01 33

  34. Mercury Vapor: Mercury compounds [except (organo) alkyls] (as Hg) • Levels for concern: • Up to 0.5 mg/m3 • Up to 1.25 mg/m3 • Up to 2.5 mg/m3 • Up to 10 mg/m3 • Emergency or planned entry into unknown concentrations or IDLH conditions • Escape Respirator Recommendations (NIOSH, Table 3 & 4) PPT-056-01 34

  35. Up to 0.5 mg/m3 • Any air-purifying half-mask respirator equipped with cartridge(s) providing protection against the compound of concern (APF 10) or • Any supplied - air respirator (APF 10) Respirators PPT-056-01 35

  36. Up to 1.25 mg/m3 • Supplied-air respirator operated in a continuous-flow mode (APF 25) or • Any powered air-purifying respirator with cartridge(s) providing protection against the compound of concern (APF 25) Canister with end of service life indicator Respirators PPT-056-01 36

  37. Up to 2.5 mg/m3 • Any air-purifying full-face piece respirator equipped with cartridge(s) providing protection against the compound of concern (APF 50) or • Any air-purifying, full-face piece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern (APF 50) ESLI required for canister, or Respirators PPT-056-01 37

  38. Up to 2.5 mg/m3 (continued) • Any supplied-air respirator that has a tight-fitting face piece and is operated in a continuous-flow mode (APF 50) or • Any powered air-purifying respirator with a tight-fitting face piece and cartridge(s) providing protection against the compound of concern (APF 50) or Respirators PPT-056-01 38

  39. Up to 2.5 mg/m3 (continued) • Any self-contained breathing apparatus with a full face piece (APF 50) or • Any supplied-air respirator with a full face piece (APF 50) Respirators PPT-056-01 39

  40. Up to 10 mg/m3 • Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode (APF 1,000) Respirators PPT-056-01 40

  41. Emergency or planned entry into unknown concentrations or IDLH conditions • Any self-contained breathing apparatus that has a full face piece and is operated in a pressure-demand or other positive-pressure mode (APF 10,000) or Respirators PPT-056-01 41

  42. Any supplied-air respirator that has a full-face piece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus (APF 10,000) Respirators PPT-056-01 42

  43. Escape • Any air-purifying, full-face piece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern. (APF 50) or • Any appropriate escape-type, self-contained breathing apparatus. • NIOSH has respirator recommendations for other mercury compounds as well: Mercury (organo) alkyl compounds (as Hg) Respirators PPT-056-01 43

  44. 29 CFR 1910.252(c)(10) • “In confined spaces or indoors, welding or cutting operations involving metals coated with mercury-bearing materials, including paint, must be done using local exhaust ventilation or airline respirators unless atmospheric tests under the most adverse conditions show that employee exposure is within the acceptable concentrations specified by 29 CFR 1910.1000. Such operations, when done outdoors, must be done using respirators approved for this purpose by NIOSH under 42 CFR part 84.” Personal Safety PPT-056-01 44

  45. Gas analyzer • Direct Mercury analyzer • Mercury vapor Mercury Detectors PPT-056-01 45

  46. Plan for response to: • Hg liquid • Hg vapor events • Have contingencies for: • Rescuer safety • Victim treatment • Multi-casualty situations Response Safety PPT-056-01 46

  47. Personal protective equipment (PPE) for staff working in each zone: • Hot Zone • Warm Zone (Decon) • Support Zone Response Safety PPT-056-01 47

  48. Having a response plan for smaller as well as larger types of potential emergencies will promote: • Personnel safety • Reduced downtime • Reduced costs Response Safety PPT-056-01 48

  49. Elemental Hg is toxic in both the liquid and vapor form • Although not as readily absorbed through the skin, the inhalation hazard is more severe • Gloves and foot protection are recommended when dealing with liquid form Response Safety PPT-056-01 49

  50. However, self-contained breathing apparatus (SCBA) and chemical protective clothing (CPC) are recommended if dealing with heated vapor • Decontaminate or dispose of clothing contacting liquid mercury Response Safety PPT-056-01 50

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