Ultrafine particle

Ultrafine particles (UFPs) are particulate matter of nanoscale size (less than 0.1 μm or 100 nm in diameter).[1] Regulations do not exist for this size class of ambient air pollution particles, which are far smaller than the regulated PM10 and PM2.5 particle classes and are believed to have several more aggressive health implications than those classes of larger particulates.[2] In the EU UFP's in ambient air are empirically defined by a technical specification. The important detail is the definition of size, stated: "The lower and upper sizes considered within this document are 7 nm and a few micrometres, respectively". Although the most common referral to UFP is "less than 0.1μm", this is incorrect for ambient air in the EU.

There are two main divisions that categorize types of UFPs. UFPs can either be carbon-based or metallic, and then can be further subdivided by their magnetic properties. Electron microscopy and special physical lab conditions allow scientists to observe UFP morphology.[1] Airborne UFPs can be measured using a condensation particle counter, in which particles are mixed with alcohol vapor and then cooled, allowing the vapor to condense around them, after which they are counted using a light scanner.[3] UFPs are both manufactured and naturally occurring. UFPs are the main constituent of airborne particulate matter. Owing to their large quantity and ability to penetrate deep within the lung, UFPs are a major concern for respiratory exposure and health.[4]

Sources and applications

UFPs are both manufactured and naturally occurring. Hot volcanic lava, ocean spray, and smoke are common natural UFPs sources. UFPs can be intentionally fabricated as fine particles to serve a vast range of applications in both medicine and technology. Other UFPs are byproducts, like emissions, from specific processes, combustion reactions, or equipment such as printer toner and automobile exhaust.[5][6] Anthropogenic sources of UFPs include combustion of gas, coal or hydrocarbons, biomass burning (i.e. agricultural burning, forest fires and waste disposal), vehicular traffic and industrial emissions, tire wear and tear from car brakes, air traffic, seaport, maritime transportation, construction, demolition, restoration and concrete processing, domestic wood stoves, outdoor burning, kitchen, and cigarette smoke.[7] In 2014, an air quality study found harmful ultrafine particles from the takeoffs and landings at Los Angeles International Airport to be of much greater magnitude than previously thought.[8] There are a multitude of indoor sources that include but are not limited to laser printers, fax machines, photocopiers, the peeling of citrus fruits, cooking, tobacco smoke, penetration of contaminated outdoor air, chimney cracks and vacuum cleaners.[3]

UFPs have a variety of applications in the medical and technology fields. They are used in diagnostic imagining, and novel drug delivery systems that include targeting the circulatory system, and or passage of the blood brain barrier to name just a few.[9] Certain UFPs like silver based nanostructures have antimicrobial properties that are exploited in wound healing and internal instrumental coatings among other uses, in order to prevent infections.[10] In the area of technology, carbon based UFPs have a plethora of applications in computers. This includes the use of graphene and carbon nanotubes in electronic as well as other computer and circuitry components. Some UFPs have characteristics similar to gas or liquid and are useful in powders or lubricants.[11]

Exposure, risk, and health effects

The main exposure to UFPs is through inhalation. Owing to their size, UFPs are considered to be respirable particles. Contrary to the behaviour of inhaled PM10 and PM2.5, ultrafine particles are deposited in the lungs,[12] where they have the ability to penetrate tissue and undergo interstitialization, or to be absorbed directly into the bloodstream — and therefore are not easily removed from the body and may have immediate effect.[2] Exposure to UFPs, even if components are not very toxic, may cause oxidative stress,[13] inflammatory mediator release, and could induce heart disease, lung disease, and other systemic effects.[14] [15][16][17] A robust association has been observed between fine particulate levels and lung cancer, and cardiopulmonary disease.[18] The exact mechanism through which UFP exposure leads to health effects remains to be elucidated, but effects on Blood pressure may play a role. It has recently been reported that UFP is associated with an increase in blood pressure in schoolchildren with the smallest particles inducing the largest effect.[19] According to research, infants whose mothers were exposed to higher levels of UFPs during pregnancy are much more likely to develop asthma.[20]

There is a range of potential human exposures that include occupational, due to the direct manufacturing process or a byproduct from an industrial or office environment,[2][21] as well as incidental, from contaminated outdoor air and other byproduct emissions.[22] In order to quantify exposure and risk, both in vivo and in vitro studies of various UFP species are currently being done using a variety of animal models including mouse, rat, and fish.[23] These studies aim to establish toxicological profiles necessary for risk assessment, risk management, and potential regulation and legislation.[24][25] [26]

Some sizes of UFPs may be filtered from the air using ULPA filters.

Regulation and legislation

As the nanotechnology industry has grown, nanoparticles have brought UFPs more public and regulatory attention.[27] UFP risk assessment research is still in the very early stages. There are continuing debates[28] about whether to regulate UFPs and how to research and manage the health risks they may pose.[29][30][31][32] As of March 19, 2008, the EPA does not yet regulate or research ultrafine particles,[33] but has drafted a Nanomaterial Research Strategy, open for independent, external peer review beginning February 7, 2008 (Panel review on April 11, 2008).[34] There is also debate about how the European Union (EU) should regulate UFPs.[35]

Political disputes

There is political dispute between China and South Korea on Ultrafine dust. South Korea claims that about 80% of ultrafine dust comes from China, and China and South Korea should cooperate to reduce the level of fine dust. China, however, argues that Chinese government have already implemented its policy regarding ecological environment. According to China's government, its quality of air has been improved more than 40% since 2013. However, the air pollution in South Korea got worse. Therefore, the dispute between China and South Korea has become political.[36] In March 2019, Seoul Research Institute of Public Health and Environment said that 50% to 70% of the fine dust is from China, therefore China is responsible for the air pollution in South Korea. This dispute provokes dispute among citizens as well.[37] In July 2014, China's paramount leader Xi Jinping and the South Korean government agreed to enforce Korea-China Cooperative Project, regarding Sharing of observation data on air pollutions, joint research on an air pollution forecast model and air pollution source identification, and human resources exchanges, etc.[38] Followed by this agreement, in 2018, China and South Korea signed China-Korea Environmental Cooperation Plan to resolute environmental issues. China Research Academy of Environmental Studies (CRAES) in Beijing is developing a building for China-Korea Environmental Cooperation Center including office building and laboratory building. Based on this cooperation, South Korea already sent 10 experts on environments to China for research, and China will also send more experts for long-term research. By this bilateral relations, China and Republic of Korea are seeking resolution on air pollution in North East Asia region, and seeks international security.

See also

References
  1. S. Iijima (1985). "Electron Microscopy of Small Particles". Journal of Electron Microscopy. 34 (4): 249.
  2. V. Howard (2009). "Statement of Evidence: Particulate Emissions and Health (An Bord Plenala, on Proposed Ringaskiddy Waste-to-Energy Facility)" (PDF). Durham Environment Watch. Archived (PDF) from the original on 2012-03-31. Retrieved 2011-04-26.
  3. John D. Spengler, John F. McCarthy, Jonathan M. Samet (2000). Indoor Air Quality Handbook. Mcgraw-hill. ISBN 978-0074455494.{{cite book}}: CS1 maint: multiple names: authors list (link)
  4. T. Osunsanya; et al. (2001). "Acute Respiratory Effects of Particles: Mass or Number?". Occupational & Environmental Medicine. 58 (3): 154–159. doi:10.1136/oem.58.3.154. PMC 1740106. PMID 11171927.
  5. B. Collins (3 August 2007). "HP Hits Back in Printer Health Scare Row". PC Pro. Archived from the original on 2007-08-10. Retrieved 2009-05-15.
  6. M. Benjamin (November 2007). "RT for Decision Makers in Respiratory Care". RT Magazine. Archived from the original on 2008-12-04. Retrieved 2009-05-15.
  7. Moreno-Ríos, Andrea L.; Tejeda-Benítez, Lesly P.; Bustillo-Lecompte, Ciro F. (2022). "Sources, characteristics, toxicity, and control of ultrafine particles: An overview". Geoscience Frontiers. 13: 101147. Bibcode:2022GeoFr..1301147M. doi:10.1016/j.gsf.2021.101147. hdl:11323/7995. S2CID 234159865.
  8. Weikel, Dan and Barboza, Tony (May 29, 2014) "Planes' exhaust could be harming communities up to 10 miles from LAX" Archived 2014-05-31 at the Wayback Machine Los Angeles Times
  9. S.M. Moghini; et al. (2005). "Nanomedicine: Current Status and Future Prospects". The FASEB Journal. 19 (3): 311–30. doi:10.1096/fj.04-2747rev. PMID 15746175. S2CID 30173777.
  10. I. Chopra (2007). "The Increasing Use of Silver-Based Products As Antimicrobial Agents: A Useful Development or a Cause for Concern?". Journal of Antimicrobial Chemotherapy. 59 (4): 587–90. doi:10.1093/jac/dkm006. PMID 17307768.
  11. "Nanotechnology: Ultrafine Particle Research". Environmental Protection Agency. 26 February 2008. Archived from the original on 2012-05-03. Retrieved 2009-05-15.
  12. Int Panis, L; et al. (2010). "Exposure to particulate matter in traffic: A comparison of cyclists and car passengers". Atmospheric Environment. 44 (19): 2263–2270. Bibcode:2010AtmEn..44.2263I. doi:10.1016/j.atmosenv.2010.04.028. S2CID 56142753.
  13. I. Romieu; et al. (2008). "Air Pollution, Oxidative Stress and Dietary Supplementation: A Review". European Respiratory Journal. 31 (1): 179–97. doi:10.1183/09031936.00128106. PMID 18166596.
  14. Brook RD; et al. (2010). "AHA Scientific Statement: Particulate Matter Air Pollution and Cardiovascular Disease". Circulation. 121 (21): 2331–2378. doi:10.1161/CIR.0b013e3181dbece1. PMID 20458016. Archived from the original on 2014-11-23. Retrieved 2014-11-13.
  15. J. Card; et al. (2008). "Pulmonary Applications and Toxicity of Engineered Nanoparticles". American Journal of Physiology. Lung Cellular and Molecular Physiology. 295 (3): L400–11. doi:10.1152/ajplung.00041.2008. PMC 2536798. PMID 18641236.
  16. L. Calderón-Garcidueñas; et al. (2008). "Long-Term Air Pollution Exposure is Associated with Neuroinflammation, an Altered Innate Immune Response, Disruption of the Blood-Brain Barrier, Ultrafine Particulate Deposition, and Accumulation of Amyloid Β-42 and Α-Synuclein in Children and Young Adults". Toxicologic Pathology. 36 (2): 289–310. doi:10.1177/0192623307313011. PMID 18349428. S2CID 21104325.
  17. Jacobs, L (Oct 2010). "Subclinical responses in healthy cyclists briefly exposed to traffic-related air pollution". Environmental Health. 9 (64): 64. doi:10.1186/1476-069X-9-64. PMC 2984475. PMID 20973949.
  18. Dockery, Douglas W.; Pope, C. Arden; Xu, Xiping; Spengler, John D.; Ware, James H.; Fay, Martha E.; Ferris, Benjamin G. Jr.; Speizer, Frank E. (1993-12-09). "An Association between Air Pollution and Mortality in Six U.S. Cities". New England Journal of Medicine. 329 (24): 1753–1759. doi:10.1056/NEJM199312093292401. ISSN 0028-4793. PMID 8179653. S2CID 25511332.
  19. Pieters, N; Koppen, G; Van Poppel, M; De Prins, S; Cox, B; Dons, E; Nelen, V; Int Panis, L; Plusquin, M; Schoeters, G; Nawrot, TS (March 2015). "Blood Pressure and Same-Day Exposure to Air Pollution at School: Associations with Nano-Sized to Coarse PM in Children". Environmental Health Perspectives. 123 (7): 737–42. doi:10.1289/ehp.1408121. PMC 4492263. PMID 25756964.
  20. Carrington, Damian (2021-05-21). "Asthma in toddlers linked to in-utero exposure to air pollution, study finds". The Guardian. Archived from the original on 2021-05-22. Retrieved 2021-05-22.
  21. A. Seaton (2006). "Nanotechnology and the Occupational Physician". Occupational Medicine. 56 (5): 312–6. doi:10.1093/occmed/kql053. PMID 16868129.
  22. I. Krivoshto; Richards, JR; Albertson, TE; Derlet, RW (2008). "The Toxicity of Diesel Exhaust: Implications for Primary Care". Journal of the American Board of Family Medicine. 21 (1): 55–62. doi:10.3122/jabfm.2008.01.070139. PMID 18178703.
  23. C. Sayes; et al. (2007). "Assessing Toxicity of Fine and Nanoparticles: Comparing in Vitro Measurements to in Vivo Pulmonary Toxicity Profiles". Toxicological Sciences. 97 (1): 163–80. doi:10.1093/toxsci/kfm018. PMID 17301066.
  24. K. Dreher (2004). "Health and Environmental Impact of Nanotechnology: Toxicological Assessment of Manufactured Nanoparticles". Toxicological Sciences. 77 (1): 3–5. doi:10.1093/toxsci/kfh041. PMID 14756123. Archived from the original on 2021-10-06. Retrieved 2019-09-09.
  25. A. Nel; et al. (2006). "Toxic Potential of Materials at the Nanolevel". Science. 311 (5761): 622–7. Bibcode:2006Sci...311..622N. doi:10.1126/science.1114397. PMID 16456071. S2CID 6900874. Archived from the original on 2021-10-06. Retrieved 2019-12-13.
  26. Notter, Dominic A. (September 2015). "Life cycle impact assessment modeling for particulate matter: A new approach based on physico-chemical particle properties". Environment International. 82: 10–20. doi:10.1016/j.envint.2015.05.002. PMID 26001495.
  27. S.S. Nadadur; et al. (2007). "The Complexities of Air Pollution Regulation: the Need for an Integrated Research and Regulatory Perspective". Toxicological Sciences. 100 (2): 318–27. doi:10.1093/toxsci/kfm170. PMID 17609539.
  28. L.L. Bergoson (12 September 2007). "Greenpeace Releases Activists' Guide to REACH, Which Addresses Nanomaterials: Nanotech Law blog of Bergeson & Campbell, P.C." Nanotechnology Law Blog. Bergeson & Campbell, P.C. Archived from the original on 2012-04-10. Retrieved 2008-03-19.
  29. W.G. Kreyling; M. Semmler-Behnke; W. Möller (2006). "Ultrafine particle-lung interactions: does size matter?". Journal of Aerosol Medicine. 19 (1): 74–83. doi:10.1089/jam.2006.19.74. PMID 16551218. Archived from the original on 2021-10-06. Retrieved 2019-12-13.
  30. M. Geiser; et al. (2005). "Ultrafine Particles Cross Cellular Membranes by Nonphagocytic Mechanisms in Lungs and in Cultured Cells". Environmental Health Perspectives. 113 (11): 1555–1560. doi:10.1289/ehp.8006. PMC 1310918. PMID 16263511.
  31. O. Günter; et al. (2005). "Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine Particles". Environmental Health Perspectives. 113 (7): 823–839. doi:10.1289/ehp.7339. PMC 1257642. PMID 16002369.
  32. S. Radoslav; et al. (2003). "Micellar Nanocontainers Distribute to Defined Cytoplasmic Organelles". Science. 300 (5619): 615–618. Bibcode:2003Sci...300..615S. doi:10.1126/science.1078192. PMID 12714738. S2CID 2359209.
  33. "How Ultrafine Particles In Air Pollution May Cause Heart Disease". Science Daily. 22 January 2008. Archived from the original on 2008-10-20. Retrieved 2009-05-15.
  34. K. Teichman (1 February 2008). "Notice of Availability of the Nanomaterial Research Strategy External Review Draft and Expert Peer Review Meeting" (PDF). Federal Register. 73 (30): 8309. Archived from the original (PDF) on May 16, 2008.
  35. J.B. Skjaerseth; J. Wettestad (2 March 2007). "Is EU Enlargement Bad for Environmental Policy? Confronting Gloomy Expectations with Evidence" (PDF). International Environmental Agreements. Fridtjof Nansen Institute. Archived from the original (PDF) on 2008-05-28. Retrieved 2008-03-19.
  36. "Outcome of 23rd Meeting of ROK-China Joint Committee and Director-General-Level Meeting on Environmental Cooperation View|Press ReleasesMinistry of Foreign Affairs, Republic of Korea". Archived from the original on 2021-10-06. Retrieved 2019-09-25.
  37. "China vowed to combat fine dust: environment minister". Yonhap News Agency. March 6, 2019. Archived from the original on September 25, 2019. Retrieved September 25, 2019.
  38. Xu, Maggie (June 26, 2018). "China, South Korea build environment cooperation". Asia News Network. Archived from the original on September 25, 2019. Retrieved September 25, 2019.

Further reading
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.