Presentation is loading. Please wait.

Presentation is loading. Please wait.

Nanotechnology Safety 1. Nanotechnology is “the Next Big Thing.” It is a truly international phenomenon that “will have a major impact on the health,

Similar presentations


Presentation on theme: "Nanotechnology Safety 1. Nanotechnology is “the Next Big Thing.” It is a truly international phenomenon that “will have a major impact on the health,"— Presentation transcript:

1 Nanotechnology Safety 1

2 Nanotechnology is “the Next Big Thing.” It is a truly international phenomenon that “will have a major impact on the health, wealth and security of the world’s people that will be at least as significant in this century as antibiotics, the integrated circuit, and manmade polymers.” National Science and Technology Council Committee on Technology, 1999

3 Top Ten Ways that Nanotechnology Will Impact Our Lives in the Next 10 years Diagnosing Diseases Treatment of Cancer and Other Diseases Widespread Adoption of Solar Energy New Batteries and Other Forms of Portable Power Blending Electronic and Paper-Based Products Lighter, Stronger, and More Conductive Materials Clean Water Low Emission Automobiles Responding to Terrorism and Environmental Disaster Increased Monitoring of Consumer Products – There are currently 807 nano products in the Consumer Products Inventory Source : NANOTECHNOLOGY LAW & BUSINESS - FALL 2007 (editors)

4 Nanotechnology Products Are Here Now Dermatone SPF 20 Natural Formula Kodak Inkjet Photo Papers Nanotec Nanoseal ® Wood Eddie Bauer Ruston Fit Nano-Tex Khakis Hummer H2 Toshiba’s Lithium- Ion Battery Kohler CleanCoat Technology Nanosolar’s Utility Panel™ Socks with Nano Silver

5 Tata’s Nano Newest Nano Product

6 PURPOSE For the present, there is minimum regulatory control for nanoparticles (NP). This suggests that for the short-term industry must self-regulate itself (take the lead in evaluating and managing risks). Localized “standards of care” or safety approaches will need to be promulgated that protect health and environmental risks when working with nanoparticles (NP). This presentation gives draft SHE “standards of care” for working with NP. 6

7 KEEP IN MIND... Current understanding of the environmental and human health effects of NP is limited. Ultimately, information about definite health effects will emerge. Until then-it will be prudent to adopt conservative approaches for managing and controlling perceived NP risks. Unfortunately, the commercialization of nanomaterials is growing so fast that it is difficult to study NP impact on human and environmental health issues. {i.e. Recent reports in Europe over “Magic Nano” spray} 7

8 DEFINITIONS Nanotechnology: simplest definition is technological developments on the nanometer (nm) scale. Nano is a prefix meaning one billionth; 1 nm = 10 -9 m Nanoparticle (NP): any substance less than 100 nm. (A single human red blood cell has a diameter about 5000 nm) Nanomaterial: any material that contains a certain proportion, or is composed entirely of, nanoparticles. Could be nanotubes, nanowires, quantum dots. 8

9 HOW BIG IS A NANOMETER? A nanometers is equal to one billionth of a meter or 10 -9 m A flea is 10 -3 m or 1 mm A human hair is 10 -4 m or 80 um A red blood cell is 10 -5 m or 7 um A strand of DNA is 10 -8 m or 2 nm A bundle of nanotubes is 1.4 nm wide A carbon 60 fullerene is 0.7 nm 9

10 10 THERE IS A CRUCIAL NEED TO STANDARDIZE TERMINOLOGY AND DEFINITIONS, DEVELOP METHODS TO MEASURE NP, AND IMPROVE CONTROL MEASURES THAT LIMIT OCCUPATIONAL EXPOSURE!

11 Silver nanowire 50 nm thick, 100 nm wide and 5 um long. (Quantronics) 11

12 Some Nanotechnology Applications Energy storage, production, and conversion Agricultural productivity enhancement Water treatment and remediation Disease diagnosis and screening (Bio- and Nano-) Drug delivery system Food processing and storage Air pollution and remediation Construction Health monitoring Vector/Pest control 12

13 13

14 GENERAL BACKGROUND NP applications will definitely expand with time. NP enhances coating surface properties. NP can be purchased or manufactured either bound or unbound. Many small particles create a large amount of surface area, which tends to become electrically charged, leading to chemically reactive conditions. NP <50 nm have properties that do not follow classical physics laws-do follow quantum physics laws. 14

15 15 Particle Number and surface area for area for 10 mg/m3 airborne particles Particle Particles/ml Particle Surface Diameter (um) of air area (um 2 /ml of air) 2.0 2 30 0.5 153 120 0.02 2,390,000 3000 Large particle Small particle

16 GENERAL BACKGROUND Safety Concerns-Small size particles (<<0.1 um) may have higher human risks than the range from 0.1 to 30 um. We know very little about most of them compared to the same substances with larger particle sizes. It is difficult to characterize worker exposure to particles that have a diameter less than the wavelength of light. Therefore SHE risk assessment technique may not directly apply! 16

17 POTENTIAL EXPOSURE RISKS 1.Airborne contamination of workplace 2.Handling of product/material 3.Cleaning/Maintenance activities 4.Leakage/Spillage Accidents 5.Product Drying 17

18 Risks? Nanotechnology – Recent Developments, Risks and Opportunities Lloyd’s of London, November 2007 – Clean-up costs of land and water contamination – Medical costs of treatment of human exposure – Liability claims from persons directly affected, environmental groups and shareholders – Unexpected life, health and workers compensation – Latent liability claims of persons affected – Business interruption while facility is investigated – Cost of product recall

19 Inhalation Exposure Studies with NM Nanoparticles not captured by respiratory defense systems Nanoparticles can enter lung tissues and be distributed to other organs and tissues Inhaled nanoparticles may pass from the nose to brain through the olfactory nerve Rigid multiwalled carbon nanotubes longer than 20 µm elicit the same toxic response in mice that asbestos does, according to two new studies Mercer -NIOSH

20 Dermal Exposure Studies with NM Reports of penetration of intact skin in test system models by: – Multi-walled carbon nanotubes – Substituted fullerenes – Quantum dots In vitro tests indicate inflammatory and cytotoxic responses after exposures to nanomaterials

21 Human Health Concerns for NM NM exposure and toxicity not yet well understood Nanoscale materials do not behave like their bulk counterparts Increased reactivity of NM due to large surface area Potential for bioaccumulation and accumulation in food chain Carbon nanotubes

22 Environmental Concerns for NM Water/soil contamination from improper disposal? Disposition and fate after product use and disposal? Degradation products? Potential for accumulation in food chain? Limited environmental testing data available

23 Occupational Concerns for NM Extent and impact of worker exposures to NM Effectiveness of personal protective equipment to minimize/eliminate NM exposures Difficulties in monitoring workplace exposures – Small size of NM – Limited protocols and methodologies Fire and explosion hazards Catalytic potential of NM Maynard 2004

24 KEY TOXICOLOGICAL FACTORS Composition and Structure Solubility Reactivity Surface Chemistry Aggregation Potential Surface Area Shape Density Particle Size 24 Chemical Related Physical Related

25 TOXICOLOGICAL ISSUES NP may be more toxic than larger particles on a mass basis (high surface area to mass ratio). The smaller the particles the more reactive and toxic they become. Deeper into lung. Not all materials will represent risks Potential for new toxicities from engineered nanomaterials? 25

26 TOXICOLOGICAL ISSUES The major routes of entry of NP into the body are: 1.Lungs (Inhalation)-Considered to be a big concern. 2.Gastrointestinal tract (Ingestion) 3.Dermal (Absorption)-Little information about dermal exposure from NP. SPE data is not readily available. Large exposure site! 26

27 TOXICITY STAGING Route of Exposure Dose Duration of Exposure Movement in Body Interaction within Body 27

28 HUMAN HEALTH EFFECTS Examples of possible health issues that have been reported in animal studies are oxidative stress, inhalation/transdermal assimilation concerns, asthma, chronic pulmonary diseases, cancer, neurodegenerative diseases, alteration of heart electrical activity, translocation (i.e. crossing of blood-brain barrier), and cell signaling. Strong evidence that pulmonary inflammation is related to surface area. At present there are no national occupational exposure standards? In fact few human research studies have been performed to date 28

29 POSSIBLE REGULATORY ACTIVITY OSHA: HAZCOMM (MSDS) EPA: RCRA, TSCA, Clean Water/Air FDA: Cosmetic Act NIOSH: Active in TiO 2 STATES 29

30 NIOSH ACTIVITY Presently involved w/drafting exposure criteria for Titanium Dioxide Material is used widely Animal studies (rat) show pulmonary inflammation, trauma, tissue damage, and lung tumors. Appears to be particle size dependent. REL of 1.5 mg/m 3 for particles 0.1 to 10 um (fine) and REL of 0.1 mg/m 3 for particles < 0.1 um (ultrafine) NOTE: Elevated lung cancer rates have been reported among workers exposed to welding fumes and diesel particulates. 30

31 HUMAN HEALTH EFFECTS It is now postulated that human health effects are more closely related to total surface area of particle than their mass-needs verification! At small particle sizes-atoms and molecules bond differently than when in bulk substances. Models that address particle deposition in the lung exist. 31

32 32 ICRP Lung Model 15 nm 3 nm

33 RECENT BIO-EFFECTS OF NP Water soluble carbon nanotubes fed intravenously to mice were excreted intact in urine and were not retained in spleen, heart, and liver. This finding gives some evidence that nanotubes might be used for medical therapeutics purposes. Reported in Proc Natl Acad Sci-USA-2006) 33

34 IF WORKING WITH UNBOUNDED NP Total enclosure of process with negative ventilation or partial enclosure with localized exhaust ventilation (LEV). Install indicators to show air flow/present of ventilation. Use dedicated exhaust system (May want double enclosure). Particle entrainment is safety feature. Treat NP as if they were a gas (high to low concentrations). Particles may undergo rapid mixing and dispersion. As NP collide coagulation/agglomeration occurs and NP can be collected in bulk form-and probably not undergo re- suspension. 34

35 IF WORKING WITH UNBOUNDED NP Beware that small particles have low settling velocity and remain airborne longer (minimal inertia). Being airborne they can be trapped on wall, ceiling, floor surfaces, and people far removed from origination point. Cover skin. Double up on gloves. Consider wearing protective long-sleeved coats (i.e. layering approach). Protective coats will need to be cleaned on a regular basis. No eating/drinking in work area. 35

36 36 T=0, Bi-modal distribution- No burner on T=2, Burner On, Notice counts & Distribution delta Count Particle size (nm) Count T=7, Burner On, Counts & Distribution the same as T=2 (minus the 10-20 nm feedstock) T=20, Burner Off, Counts high initially for small particles-large particles not being made. Distribution is similar to that for T=0 T=30, Burner Off & Room beginning to “Normalize” (a.k.a. getting back to background bi-modal distribution). Notice that the particulate counts are down drastically also … supporting the “Wait for 5- minutes before you enter the chamber Rule”

37 IF WORKING WITH UNBOUNDED NP HEPA filters/scrubbers (also N100) can be useful for particles less than 100 nm (efficiency increases as particle size decreases). Not sure about their use at 2- 10 nm. Need to be aware of facial seal leakage potential. Will be difficult to clean and maintain laboratory equipment (as well as walls/floors) containing nanoparticles without exposing workers (use of wet methods) It is not clear that existing knowledge about conventional chemicals can be applied predict risks of nanomaterials. 37

38 IF WORKING WITH UNBOUNDED NP Limit the number of workers per room involved with NP. Reduce actual exposure time. Potential for dust explosions/fires: composition, increased surface area, NP in air longer… 38

39 IF WORKING WITH UNBOUNDED NP Electrostatic air filters may be use to collect NP since charged particles have higher deposition efficiency than uncharged particles. Some work being done with soft x-rays and charged particles to further enhance collection NP may act synergistically with O 2 and NO x Laser Generated Air Contaminants (LGAC) could be a source of NP. Some basic medical surveillance for lung capacity/skin issues may be necessary. 39

40 IF WORKING WITH UNBOUNDED NP At present, MSDS does not reflect nanospecificity. Not sure if OSHA defines NP as falling under Hazard Communication. “Bio-accumulation” of particles can occur in plants, crops, water, and ground. Problems w/waste disposal (options: encapsulation or incineration). May need to consider life-cycle testing on products. Avoid future liabilities In view of the above concepts perhaps it is best not to work with unbounded NP! 40

41 41 CONTROL OF WORKPLACE EXPOSURES TO NP. Engineering Controls Training and Good Work Practices Personal Protective Equipment


Download ppt "Nanotechnology Safety 1. Nanotechnology is “the Next Big Thing.” It is a truly international phenomenon that “will have a major impact on the health,"

Similar presentations


Ads by Google