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Manufactured Nanomaterials

Manufactured Nanomaterials. Aluminum oxide Cerium oxide Iron nanoparticles Silver nanoparticles Titanium dioxide Zinc oxide Silicon dioxide Polystyrene. Dendrimers Nanoclays Carbon black Fullerenes (C60) Single-walled carbon nanotubes (SWCNTs) Multi-walled carbon nanotubes (MWCNTs).

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Manufactured Nanomaterials

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  1. Manufactured Nanomaterials Aluminum oxide Cerium oxide Iron nanoparticles Silver nanoparticles Titanium dioxide Zinc oxide Silicon dioxide Polystyrene Dendrimers Nanoclays Carbon black Fullerenes (C60) Single-walled carbon nanotubes (SWCNTs) Multi-walled carbon nanotubes (MWCNTs)

  2. Nanotechnology Safety and Health Issues and Concerns Dennis J. Cesarotti, PhD, CIH, CSP (deceased) Department of Technology, Northern Illinois University Martin Kocanda, MSEE, Ph.D. College of Engineering and Engineering Technology

  3. Nanotechnology • Manipulation of matter at a nanometers scale producing structures, materials, and devices. • Particles 100 nanometer or less. • Does size really make a difference relative to the safety and health of nano-particles?

  4. Objectives: Safety and Health, Issues and Concerns

  5. TLO 1: How nanotechnology influences the hazards of a chemical Enabling Objectives Define the hazards of chemicals. Identify potential hazards. Recall examples of specific nano-particles.

  6. TLO 2: What nanotechnology is in relation to human physiology Enabling Objectives Recall function and structures of the human body. Contrast the size of nano-particles to the components of the human body.

  7. TLO 3: How can humans be exposed to nanomaterials Enabling Objectives Describe the routes of entry into the human body. List common activities that could contribute to exposure.

  8. TLO 4: How nanoparticles may influence human health Enabling Objectives Describe the potential health effects on the systems of the body. List the common symptoms and etiology associated with the health effects.

  9. TLO 5: What exposure control measures can be used to minimize adverse health effects Enabling Objectives Discuss control options. Compare and contract the control methodology. Determine the effectiveness of control measures.

  10. TLO 6: What forms of medical surveillance can be used to diagnose early adverse health effects Enabling Objectives Explain the importance of a detailed medical history. Discuss the role of exposure monitoring. List the medical surveillancetechniques.

  11. TLO 1: How does nanotechnology influence the hazards of a chemical?

  12. Hazards of a Chemical? Flammability Corrosivity Toxicity Reactivity

  13. Fire and Explosion risks This applies to metals and organic materials. The risk is likely to be highest if nanodusts are formed during the production process (e.g. if when spray drying a Suspension of nanoparticles, the solvent evaporates during the process and a nanoaerosol is created.

  14. Flammability Flashpoint: The lowest temperature of a fuel where sufficient vapor is present to result in a fire or explosion if a source of ignition is present. Auto Ignition Temperature: Lowest temperature where the chemical will breakdown and ignite.

  15. Flammability (continued) Explosive Limits LEL: Lowest concentration of fuel in the air; expressed as a percent. UEL: Highest concentration of fuel in the air for combustion. Above UEL, fuel rich, will not burn. Flammable Range Difference between UEL and LEL

  16. Combustible Dusts (continued) Combustible dust size < 40 um. Minimum explosive concentration (MEC). Decreasing the particle size increases the potential for and rate of combustion.

  17. Combustible Dusts (continued) Minimum ignition temperature. Minimum ignition energy (MIE). < 3 mJ = high sensitivity> 10 mJ = low sensitivity

  18. Explosivity Scale Class II test Ignition Sensitivity (IS) > 0.2 IS = TIm * EIm * CEm (time, energy, concentration) Normalized to Pittsburgh coal (PC/D) Explosion Severity (ES) > 0.5 ES = PEM * RPRM (max pressure and max pressure rise) Normalized to Pittsburgh coal (D/PC) US Bureau of Mines developed the standard

  19. Combustible Dusts (continued) • Kst Test • Maximum normalized rate of pressure rise (dP/dt) • Kst = (dP/dt)M V1/3

  20. http://www.farrapc.com/articles/explosion-venting-requirements/affectedhttp://www.farrapc.com/articles/explosion-venting-requirements/affected

  21. Combustible Dusts (continued) Flammable particles Carbon Metals Organic polymers

  22. Combustible Dusts (continued) Large surface / volume ratio. Bulk materials do not easily ignite. “Pile” of powder does not easily ignite. Dispersed powder is very explosive. http://www.teachertube.com/viewVideo.php?title=Dust_Explosion&video_id=155518 http://www.metacafe.com/watch/587885/simulate_a_dust_explosion/ http://www.ebaumsworld.com/video/watch/80623061/

  23. Corrosivity pH measure of corrosivity Scale from 0 to 14 Acids: pH of 0 to 6.9 Caustics or bases: pH of 7.1 to 14 pH 7: neutral

  24. Corrosivity (continued) Concerns Acids < 2.0 Bases > 12.0 Corrosive to tissue Acids sit on surface Can be washed off quickly Local damage Bases Can penetrate tissue

  25. Toxicity Paracelsus (1493 - 1541) “All substances are poisons, there is none which is not a poison. The right dose differentiates a poison and a remedy.” The dose makes the poison

  26. Toxicity (continued) Exposure Factors Concentration Duration Frequency Size Route of Entry Total body dose

  27. Toxicity:(continued) Response (effect) NOEL NOAEL Dose No Observed Effect Level No Observed Adverse Effect Level Dose Response Curve

  28. Toxicity:(continued) + 1s (67 %) Number of Responses + 2s (95 %) Minimal Mean Extreme Degree of Response

  29. Toxicity:(continued) Typical Health Effects Irritation Corrosive Allergen Asphyxiant Systemic Carcinogenic Reproductive

  30. Toxicity:(continued) Chemical exposures are generally divided into two categories: Acute Chronic Symptoms of an acute exposure may be completely different from those resulting from chronic exposure

  31. Toxicity: “Acute Exposure” • Symptoms usually occur during or shortly after exposure to a sufficiently high concentration of a contaminant • Concentration required to produce such effects varies widely from chemical to chemical

  32. Toxicity: “Chronic Exposure” Generally refers to exposures to low concentrations of a contaminant over a long period of time The “low” concentrations required to produce symptoms of chronic exposure depend upon: The chemical The duration of each exposure The number of exposures

  33. Reactivity Ability to reach with other molecules Chemical reaction Polymerization Decomposition Oxidation Reduction Release of Heat Pressure “Other” particles

  34. Reactivity (continued) Otherwise inert materials can be highly reactive Nanoparticles can generate heat through the progression of reactions

  35. Where can this safety information be found? Material Safety Data Sheet (MSDS) Review of MSDS Handout for Propane

  36. Homework Assignment Write two paragraph explanation that compares: Graphite powder and silica dessicant powder. Address all of the key safety issues. What make the materials different? What is the common safety risk of both? Perform a web search for the MSDS for each.

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