News Article | November 16, 2016
New Johns Hopkins Bloomberg School of Public Health-led research suggests that some workers at industrial hog production facilities are not only carrying livestock-associated, antibiotic-resistant bacteria in their noses, but may also be developing skin infections from these bacteria. The findings are published Nov. 16 in PLOS ONE. "Before this study, we knew that many hog workers were carrying livestock-associated and multidrug-resistant Staphylococcus aureus strains in their noses, but we didn't know what that meant in terms of worker health," says study leader Christopher D. Heaney, PhD, an assistant professor at the Bloomberg School's departments of Environmental Health and Engineering, and Epidemiology. "It wasn't clear whether hog workers carrying these bacteria might be at increased risk of infection. This study suggests that carrying these bacteria may not always be harmless to humans." Because the study was small, the researchers say there is a need to confirm the findings, but the results highlight the need to identify ways to protect workers from being exposed to these bacteria on the job, and to take a fresh look at antibiotic use and resistance in food animal production. Hogs are given antibiotics in order to grow them more quickly for sale, and the overuse of antibiotics has been linked to the development of bacteria that are resistant to many of the drugs used to treat staph infections. The researchers, involving collaborators at the University of North Carolina at Chapel Hill, the Rural Empowerment Association for Community Help in Warsaw, NC, and the Statens Serum Institut in Copenhagen, enrolled 103 hog workers in North Carolina and 80 members of their households (either children or other adults) to have their noses swabbed to determine whether they were carrying strains of S. aureus in their nasal passages. Each person was also shown pictures of skin and soft tissue infections caused by S. aureus and asked if they had developed those symptoms in the previous three months. The researchers found that 45 of 103 hog workers (44 percent) and 31 of 80 household members (39 percent) carried S. aureus in their noses. Nearly half of the S. aureus strains being carried by hog workers were mutidrug-resistant and nearly a third of S. aureus strains being carried by household members were. Six percent of the hog workers and 11 percent of the children who lived with them reported a recent skin and soft tissue infection (no adult household members reported such infections). Those hog workers who carried livestock-associated S. aureus in their noses were five times as likely to have reported a recent skin or soft tissue infection as those who didn't carry those bacteria in their noses. The association was stronger among hog workers who carried multidrug-resistant S. aureus in their noses, who were nearly nine times as likely to have reported a recent skin or soft tissue infection. Multidrug-resistant S. aureus infections can be difficult to treat because the antibiotic drugs that doctors typically prescribe don't work. Researchers are concerned about what might happen if these bacteria develop the capacity to spread more broadly between animals and humans. While the study is small, Heaney says the findings suggest that more work is needed to figure out how to mitigate S. aureus exposure and the risk of infection among workers and to track the extent to which these livestock-associated bacteria may spread into the community at large. Since the study found that those hog workers who never wore protective masks over their nose and mouth were more likely to be carriers of the bacteria than those who did, Heaney says recommendations about wearing personal protective equipment might be prudent. Heaney says 89 percent of the hog workers in the study were Hispanic and that many are likely without health insurance. Studies like this, he says, can help focus on risks to a population that is vulnerable and may otherwise fall through the cracks. According to a Duke University analysis of U.S. Bureau of Labor Statistics data, roughly 327,350 people were employed in hog farming in the United States in 2012. Most evidence about the burden of human infections associated with drug-resistant S. aureus nasal colonization comes from studying strains that circulate in hospital settings, where patients are often tested upon admission so that medical staff can take precautions. Less is known about whether generally healthy people in the community, such as hog workers, are at increased risk of developing S. aureus infections. The rise of multidrug-resistant bacteria - often called superbugs - is a global crisis according to the World Health Organization and the use of antibiotics in food animal production has been highlighted as an important contributor. Roughly 80 percent of antibiotics sold in the United States are used in animals, with heavy nontherapeutic uses in food animal production. "This issue isn't going away and there are many more research questions that need to be answered," he says. "Livestock-associated, antibiotic-resistant Staphylococcus aureus nasal carriage and recent skin and soft tissue infection among industrial hog operation workers" was written by Maya Nadimpalli, Jill R. Stewart, Elizabeth Pierce, Nora Pisanic, David C. Love, Devon Hall, Jesper Larsen, Karen C. Carroll, Tsigereda Tekle, Trish M. Perl and Christopher D. Heaney. Funding for this study was provided by the National Institute for Occupational Safety and Health (1K01OH010193-01A1), the Johns Hopkins NIOSH Education and Research Center, the Johns Hopkins Center for a Livable Future, the Sherrilyn and Ken Fisher Center for Environmental Infectious Diseases Discovery Program at the Johns Hopkins University School of Medicine (018HEA2013), the National Science Foundation (1316318), the National Institute of Environmental Health Sciences (5T32ES007141-30), the Royster Society fellowship, an Environmental Protection Agency Science to Achieve Results fellowship the GRACE Communications Foundation and the National Institute for Allergy and Infectious Diseases (1R01AI101371-01A1).
News Article | December 2, 2016
BETHLEHEM, PA--(Marketwired - Dec 2, 2016) - Experts will present a panel discussion on "Understand the Evidence and Requirements from USP < 800 > to the NIOSH Universal Testing Draft Protocol" at a B. Braun Medical Inc. sponsored symposium during the American Society of Health-System Pharmacists (ASHP) 51st Midyear Clinical Meeting. The symposium for continuing education credits will be held on Tuesday, Dec. 6, from 11:30 a.m. to 1:00 p.m. at the South Pacific J North Convention Center at Mandalay Bay in Las Vegas. Featured speakers at the Continuing Professional Education (CPE) symposium include Jay Brown, Director of Pharmacy, Novant, NC; Paul Sessink, CEO Exposure Controls, Sweden; Ian Pengelly, Analytical Chemist, HSL, UK; and Alan Wilkinson, Director Biopharma Stability Testing Laboratory, UK. "More than 540 B. Braun customers in the U.S. use OnGuard® CSTD, designed to help protect healthcare workers and meet USP < 800 > requirements," said Joe Cleary, Group Product Director for Pharmacy Admixture at B. Braun. "Unfortunately there's a lot of misinformation in the marketplace regarding the regulations and how to interpret evidence," he said. "Our mission is to ensure pharmacists get the facts to make objective purchasing decisions." From Dec. 5-7, B. Braun representatives at booth #1655 will demonstrate the use of the OnGuard CSTD, and scientists from Biopharma Stability Testing Laboratory will be available to answer questions on different CSTD testing approaches. General Chapter < 800 >, Hazardous Drugs - Handling in Healthcare Settings, published in February 2016, was developed by the U.S. Pharmacopeial Convention Compounding Expert Committee to protect healthcare workers, including pharmacists, from residual exposure in healthcare settings. B. Braun Medical Inc., a leader in infusion therapy and pain management, develops, manufactures, and markets innovative medical products and services to the healthcare industry. The company is committed to eliminating preventable treatment errors and enhancing patient, clinician and environmental safety. B. Braun Medical is headquartered in Bethlehem, Pa., and is part of the B. Braun Group of Companies in the U.S., which includes B. Braun Interventional Systems, Aesculap® and CAPS®. Globally, the B. Braun Group of Companies employs more than 56,000 employees in more than 60 countries. Guided by its Sharing Expertise® philosophy, B. Braun continuously exchanges knowledge with customers, partners and clinicians to address the critical issues of improving care and lowering costs. To learn more about B. Braun Medical, visit www.BBraunUSA.com.
News Article | February 17, 2017
Health and safety concerns about fracking are huge and likely to grow even more if Scott Pruitt, a man who has been described as a “stenographer for the oil and gas industry," is confirmed as director of the Environmental Protection Agency. Pruitt has sued the EPA repeatedly while he was the attorney general in Oklahoma—a state suffering multiple earthquakes as a result of fracking, and where he took no action. This multipart report will review some of the myriad of health and environmental concerns and the competing business interests surrounding fracking. In order to understand the health problems, you need to first understand how fracking is done. Thousands of feet deep below the ground surface, some types of rocks, particularly shale, a soft-layered rock formed from mud and clay, contain gas and oil. The problem is how to release the gas and oil from the rock. For hydraulic fracturing, a.k.a. fracking, a well is initially drilled to an average depth of 7,700 feet. When it reaches the right depth, the well drill and pipes are redirected horizontally, extending 1,000-6,000 feet. A mixture of water, sand and chemicals is injected into the wells under high pressure to fracture, or crack, the shale, enabling gas to be released and flow up the well. The process requires heavy construction equipment. It’s estimated that 200 tankers are needed to haul in 1 million gallons of water, and that each deep well might require 2-10 million gallons of water mixed with thousands of gallons of a sand “proppant" and chemical mixture. What makes fracking especially hazardous is the very high pressure needed to shatter the rock, and that the metal and concrete well casings are often not strong enough to tolerate the intense pressure, resulting in leaks of toxic fluids. This "well integrity" has NOT been safer in new wells. In addition to the chemicals injected into the wells during the fracking process, other chemicals are released from the shale, including these: But there are many others…and many of these are proprietary and, thanks to the “Halliburton Loophole,” which exempted the injection of these fracking chemicals (now euphemistically called “tools”) from the EPA’s regulation under the Safe Drinking Water Act. In many states, companies don’t even have to disclose what these chemicals are that they are injecting into these wells. Some states, like Pennsylvania, have even had gag orders prohibiting physicians who were given access to these trade secret concoctions in order to take care of their patients from disclosing this information either to other physicians or to the patients themselves! This gag rule was overturned in December, 2013. A similar rule was recently proposed in Virginia, and another, in Maryland, has been withdrawn. What do we know about some of these chemicals? During fracking, a number of chemicals are released into the air, as well as into the water. Benzene is one, naturally occurring in the rock but toxic when vented into the air. Dr. Carol Kwiatkowski of University of Colorado, examined air samples within a mile of shale gas wells. Her team found 61 airborne chemicals, including methylene chloride, which can cause respiratory symptoms and memory loss, and can be fatal acutely, as well as being a possible carcinogen in the longer term. The Colorado researchers also found levels of polycyclic aromatic hydrocarbons well above the threshold shown to cause lower IQs and developmental delays in prenatal exposures. Increased levels of radon, the second most common cause of lung cancer in the U.S., has been increasing in homes near unconventional (horizontal) drilling (a.k.a. fracking). Besides the chemical exposures, oil and gas drilling workers have a much higher fatality rate than average—2.5x that of the construction industry and 7x higher than industry as a whole. Silicosis is an additional risk borne by the drilling workers. The National Institute for Occupational Safety and Health (NIOSH)’s field studies show that workers may be exposed to high levels of silica in the dust surrounding the work site, even if using respirators, which are often inadequate to compensate for the high levels of exposure. The silica crystals then enter the workers’ lungs, causing difficulty breathing and permanent lung damage. Besides disability and premature death from chronic obstructive lung disease (COPD), lung cancer is also a risk. The EPA has equivocated as to health problems from water contamination. In 2015, it said it had found no evidence that fracking had “led to widespread, systemic impacts on drinking water resources,” although it did find specific instances of problems, including contamination of drinking water wells. It revised its report in December 2016, noting that there was evidence that “fracking contributed to drinking water contamination—'cases of impact'—in all stages of the process,” as ProPublica explained in its in-depth series on fracking. ProPublica also notes that in Dimock, Pa., the EPA concluded that their foul, brown water “did not require emergency action, such as a federal cleanup.” Yet another study of the same water, by the CDC’s Agency for Toxic Substances and Disease Registry, found dangerously high levels of lead, cadmium, arsenic and copper in residents’ wells, as well as non-natural pollutants including acetone, toluene and chloroform, and a compound called 4-chlorophenyl phenyl ether. The water in 17 homes contained enough methane to risk an explosion. Overall, it appears the EPA has downplayed risks to the public from contaminated water in a number of cases. Two new reports from the Public Herald are damning. In a multiyear study of fracking in Pennsylvania, the investigative journalists contacted the Department of Environmental Protection repeatedly. In their first report, "Hidden Data," they note that in 2011, DEP “never produced a single document, and we (PH) learned that complaints were being held as 'confidential.'" When asked why, an attorney from DEP’s Southwest Regional Office explained that Deputy Secretary Scott Perry didn’t want complaints to ‘cause alarm.’” By December 2016, through the reporters' dogged persistence, the DEP produced a new list revealing a statewide total of 9,442 complaints from 2004 onwards. Dr. Anthony Ingraffea, an oil and gas engineering expert from Cornell University, analyzed the data. From a baseline in 2004, where there was one complaint for every 10 conventional wells that were drilled, to one complaint per unconventional (fracked) well, now there are two complaints per well, with the number of complaints now exceeding the number of gas wells. The DEP now receives an average of three oil and gas complaints per business day. Yet the DEP concluded that only 6% of the drinking water complaints were related to the drilling. In their newly released report, “To Hell With Us,” the investigators reviewed 1,000 of the DEP’s 4,108 drinking water complaints, finding 177 cases of misconduct by the DEP. They detail each report here. (Many of the remaining reports were incomplete, precluding analysis.) They divide the violations into three types: The reporters conclude that DEP “cooks” its findings and shreds reports prematurely, precluding further analysis. A number of states and countries currently ban fracking, including Monterey County and five others in California, the states of New York, Maryland (though this is being reconsidered) and Florida and counties in Ohio, Texas and Pennsylvania, among others. Local decisions to ban fracking because of concerns about the environment and water quality are increasingly being challenged. It should be obvious that it is critical to all of us to have clean air and water, and that this issue should be above politics and business interests. Scott Pruitt is but the latest example of nominating a candidate who is most likely to dismantle an essential department to a cabinet position. Perhaps, as industry would claim, there is “nothing to see here” and no problem…but we don’t know, given limited research and that not many are looking. Is this an experiment we should be doing on our children? Further posts in this series will look more deeply at health studies and the impact of fracking on local communities. For more medical/pharma news and perspective, follow me on Twitter @drjudystone or here at Forbes
News Article | February 28, 2017
Shimadzu Scientific Instruments, Inc. (Columbia, MD) and MIDI, Inc. (Newark, DE) have formed a strategic partnership to develop and market automated chromatographic solutions for agri-biotech, biodefense, dietary supplement, food science, forensics and renewable energy laboratories. These automated testing solutions will save analysis time and reduce labor costs, while providing unprecedented analytical accuracy over the “manual” chromatography approaches used in these industries. Under the terms of the agreement, Shimadzu is combining its 2010 GC, i-Series UHPLC, GCMS chromatography systems and LabSolutions™ software with MIDI, Inc.’s expert system software. Sherlock™ chromatography analysis software is a comprehensive and powerful data analysis platform, which precisely names compounds, performs complex pattern recognition and gives customers the ability to visually analyze their data in many different ways. Results are delivered automatically, reproducibly and objectively. The first product launch will be for automated microbial identification and soil phospholipid fatty acid (PLFA) analysis on Shimadzu’s 2010 GC product line, followed by solutions for the UHPLC and GCMS instruments. Gary Jackoway, MIDI Inc.'s Vice President and Director of Software Development, said, “We are delighted to partner with Shimadzu Scientific Instruments and have been impressed by their technology, team and customer support philosophy. This partnership will make automated and precise chromatography available to more customers than ever before and allow those customers to achieve maximum efficiency, reduce the learning curve and lower their labor costs.” “Shimadzu Scientific Instruments, Inc. is pleased to establish this important partnership. MIDI, Inc. has a long history of expertise in successfully automating and analyzing complex chromatographic data in growth markets. By combining their Sherlock™ software platform with state-of-the-art Shimadzu analytical instrumentation, along with our breadth of sales and support, we can offer even more customer-focused solutions,” said Mark Janeczko, Shimadzu Scientific Instruments, Inc. Marketing Manager. The Shimadzu and MIDI-integrated products will be exhibited at the 2017 Pittsburgh Conference and Expo - booth #4112. About Shimadzu Scientific Instruments, Inc. Established in 1975, Shimadzu Scientific Instruments (SSI), the American subsidiary of Shimadzu Corporation (Kyoto, Japan), provides a comprehensive range of analytical solutions to laboratories throughout North, Central, and parts of South America. SSI maintains a network of nine regional offices strategically located across the United States, with experienced technical specialists, service and sales engineers situated throughout the country, as well as applications laboratories on both coasts. For more information, please visit http://www.ssi.shimadzu.com. About MIDI, Inc. MIDI, Inc. is a private biotechnology company that specializes in automated and precise chromatography solutions. Founded in 1991, MIDI’s Sherlock™ software platform is used by scientists in more than 45 countries for automated analysis of: dietary supplements, fatty acids (FAME), fire debris, microbes, soil phospholipid fatty acids (PLFA) and spices. Sherlock™ has been US FDA 501(k) cleared for the identification of Bacillus anthracis (Anthrax pathogen) and Mycobacterium tuberculosis (TB pathogen). In addition, Sherlock™ is AOAC INTERNATIONAL cleared for Bacillus anthracis and US CDC-NIOSH cleared for aerobic bacterial identification. For more information, please visit http://www.midi-inc.com
News Article | December 16, 2016
New data show many more coal miners across Appalachia suffering from the most serious form of black lung disease than federal regulators previously reported. National Public Radio says (http://n.pr/2hWzhSi ) its investigation shows cases 10 times more prevalent, with 11 black lung clinics in Virginia, West Virginia, Pennsylvania and Ohio recording 962 cases so far this decade. The National Institute for Occupational Safety and Health said Thursday that 60 current and former miners —from Pike, Floyd, Letcher and Knott counties in Kentucky — were diagnosed with progressive massive fibrosis, the most severe form of black lung, between January 2015 and last August. The NIOSH findings, first reported by the Lexington Herald-Leader, spike from 31 cases identified nationwide from 1990-1999. Black lung has caused about 78,000 deaths since 1968.
News Article | February 23, 2017
The oil and gas industry is always innovating and for related trades, like transportation, it is important to keep up. That is why Arrows Up, LLC., an affiliate of OmniTRAX Inc., has introduced a revolutionary method to get frac sand into the blender at the wellhead in a way that eliminates dust, saves time and cuts costs. “Anyone who has ever fracked a well knows there are a million things to consider when it comes to safety, costs and efficiencies,” said Ken White, Director of Sales for Arrows Up, LLC. “Our system makes their job easier by providing a last-mile containerized proppant delivery solution that addresses all three of those business priorities.” Speaking at the North American Frac Sand Exhibition & Conference, today, White will explain how their delivery solution combines unitized Jumbo Bins with a riser that allows the sand to be directly discharged into the blender at the wellhead. This flexible system offers tailored solutions that customers love because it reduces transportation costs and demurrage without compromising safety. In fact, the patent-pending containers are proven to substantially reduce silica dust, which is heavily regulated by the National Institute for Occupational Safety and Health (NIOSH). The Arrows Up Jumbo Bin can hold 25 tons of frac sand and decrease product shrinkage by reducing the number of times the product needs to be transferred. It can also be moved by standard transportation equipment, giving customers the flexibility they need to control costs. White’s presentation is entitled: “Creating Supply Chain Efficiencies Through Unitized Solutions for Last-Mile Delivery.” Ken White Bio: Ken White has been in Business Development and Product Integration for over 25 years. The last 5 years he has been providing proppants to the oil and gas industry nationwide. He has an extensive background in all types of proppants from ceramic proppant, resin coated proppant, as well as northern and southern sands. He has been heavily involved in understanding the importance of the integrity of these products, which includes logistics and delivery to the blender. Ken joined Arrows UP, LLC in 2017 as the Director of Sales and has been tasked the role of growing the Arrows Up footprint. Ken attended Ouachita Baptist University as a Business Major in Arkadelphia, Arkansas. About OmniTRAX, Inc. As one of North America’s largest private railroad and transportation management companies, OmniTRAX’s core capabilities range from providing management services to railroad and port services and to intermodal and industrial switching operations. Through its affiliation with The Broe Group and its portfolio of managed companies, OmniTRAX also has the unique capability of offering specialized industrial development and real estate solutions, both on and off the rail network managed by OmniTRAX. More information is available at http://www.omnitrax.com. About Arrows Up, LLC. Arrows Up, LLC. began following a company’s request to create better products to serve the bulk storage and transportation industry. The management and operations teams of Arrows Up have over 65 years of combined experience in the packaging and logistics industry. Our mission is to create innovative, efficient and safer solutions for the bulk storage and transportation industries. This will be accomplished by research, customer involvement and continued experimentation with materials, design and assemble concepts. More information is available at http://www.arrowsupllc.com/.
News Article | February 12, 2017
When I offered to write a Pump Handle review of Dr. Paul Blanc’s new book Fake Silk, I had no idea that it would make me question the clothes I was wearing, which I believe to be “environmentally sustainable.” I didn’t even put that connection together after hearing Blanc speak at a recent book-signing party in Los Angeles. But at the party, Dr. Blanc mentioned that “rayon” (or “fake silk”) fibers had once been made in Axis, Alabama at a plant that went through several owners with one of its novel rayon patents (for a product called Tencel), bought out by Lenzing Fibers. Lenzing advertises the fabric it as Tencel – “a botanic fiber”… “that comes from nature.” As I delved into the frightening tale that is Blanc’s book, I read about Lenzing and its sordid history during World War II in Austria. The pants I have confidently bought from a local L.A. manufacturer are made of, you guessed it, Tencel, and apparently by Lenzing Fibers. That certainly spurred my interest in reading the whole story behind “Fake Silk”! As part of his worldwide research for the book, Dr. Blanc visited the Lenzing plant in Austria and reviewed the NIOSH archives on Axis, Alabama, among many other locales. Notable about the Austrian plant was its use in WWII for slave labor by the Nazis, where the plant made fabric for military and other uses. Like most of the industry, the plant’s process for creating rayon, or viscose, emitted the toxic chemical, carbon disulfide, the underlying topic of Blanc’s book. Exposure to this chemical causes severe neurologic problems, to the point that workers at manufacturing sites in the U.S. and around the world actually committed suicide after overexposure to it. Others developed Parkinson’s or suffered strokes. In an interview last week with Canadian Broadcasting Corporation (CBC), Blanc said: Author Paul Blanc, who holds an endowed chair at UC San Francisco School of Medicine, is an occupational health physician. But this book illustrates how he is so much more… an historian… a humanist… a corporate investigator… and someone who understands both politics and economics. His book reflects a wide range of intellectual interests. Fake Silk tells the story of “the lethal history of viscose rayon” during WWI and WWII, how the industry moved to developing countries, and efforts of corporations to “greenwash” viscose. But back to Tencel for a moment. It is hard to fathom that the fabric in my clothing is made by a company that once used slave labor under the Nazis. But actually, it turns out that Tencel is an innovation that does not require carbon disulfide, although it is unclear how toxic the alternative solvent used (something called “NMMO”) might be; NMMO is usually referred to as “benign.” Tencel is a small part of the overall viscose market, which also includes carbon disulfide-using cellophane and rayon sponges which are common in kitchens. For those of us whose careers started out in the 1970s with occupational health, and for those of us who have since been involved more in environmental health (rather than worker safety) issues, this book shows the close connection between the two fields. Workers got sick inside the plants from carbon disulfide exposure; nearby residents got sick from what the plants emitted. As I bet many Pump Handle readers do, I think of myself as someone who knows quite a bit about the history of worker health. But I had no idea about the grim history that Paul Blanc so compellingly describes, with meticulous footnotes. I hope you will enjoy reading Paul Blanc’s history of this industry as much as I did – even though being horrified by the tale that he unravels. Andrea Hricko is a professor of preventive medicine at the University of Southern California.
Castranova V.,NIOSH |
Schulte P.A.,U.S. National Institute for Occupational Safety and Health |
Zumwalde R.D.,U.S. National Institute for Occupational Safety and Health
Accounts of Chemical Research | Year: 2013
Carbon nanotubes (CNTs) are carbon atoms arranged in a crystalline graphene lattice with a tubular morphology. CNTs exhibit high tensile strength, possess unique electrical properties, are durable, and can be functionalized. These properties allow applications as structural materials, in electronics, as heating elements, in batteries, in the production of stain-resistant fabric, for bone grafting and dental implants, and for targeted drug delivery. Carbon nanofibers (CNFs) are strong, flexible fibers that are currently used to produce composite materials.Agitation can lead to aerosolized CNTs and CNFs, and peak airborne particulate concentrations are associated with workplace activities such as weighing, transferring, mixing, blending, or sonication. Most airborne CNTs or CNFs found in workplaces are loose agglomerates of micrometer diameter. However, due to their low density, they linger in workplace air for a considerable time, and a large fraction of these structures are respirable.In rat and mouse models, pulmonary exposure to single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), or CNFs causes the following pulmonary reactions: acute pulmonary inflammation and injury, rapid and persistent formation of granulomatous lesions at deposition sites of large CNT agglomerates, and rapid and progressive alveolar interstitial fibrosis at deposition sites of more dispersed CNT or CNF structures.Pulmonary exposure to SWCNTs can induce oxidant stress in aortic tissue and increases plaque formation in an atherosclerotic mouse model. Pulmonary exposure to MWCNTs depresses the ability of coronary arterioles to respond to dilators. These cardiovascular effects may result from neurogenic signals from sensory irritant receptors in the lung. Pulmonary exposure to MWCNTs also upregulates mRNA for inflammatory mediators in selected brain regions, and pulmonary exposure to SWCNTs upregulates the baroreceptor reflex. In addition, pulmonary exposure to MWCNTs may induce levels of inflammatory mediators in the blood, which may affect the cardiovascular system. Intraperitoneal instillation of MWCNTs in mice has been associated with abdominal mesothelioma. MWCNTs deposited in the distal alveoli can migrate to the intrapleural space, and MWCNTs injected in the intrapleural space can cause lesions at the parietal pleura. However, further studies are required to determine whether pulmonary exposure to MWCNTs can induce pleural lesions or mesothelioma.In light of the anticipated growth in the production and use of CNTs and CNFs, worker exposure is possible. Because pulmonary exposure to CNTs and CNFs causes inflammatory and fibrotic reactions in the rodent lung, adverse health effects in workers represent a concern. NIOSH has conducted a risk assessment using available animal exposure-response data and is developing a recommended exposure limit for CNTs and CNFs.Evidence indicates that engineering controls and personal protective equipment can significantly decrease workplace exposure to CNTs and CNFs. Considering the available data on health risks, it appears prudent to develop prevention strategies to minimize workplace exposure. These strategies would include engineering controls (enclosure, exhaust ventilation), worker training, administrative controls, implementation of good handling practices, and the use of personal protective equipment (such as respirators) when necessary. NIOSH has published a document containing recommendations for the safe handling of nanomaterials. © This article not subject to U.S. Copyright. Published 2012 by the American Chemical Society.
American journal of physiology. Lung cellular and molecular physiology | Year: 2014
The hallmark geometric feature of single-walled carbon nanotubes (SWCNT) and carbon nanofibers (CNF), high length to width ratio, makes them similar to a hazardous agent, asbestos. Very limited data are available concerning long-term effects of pulmonary exposure to SWCNT or CNF. Here, we compared inflammatory, fibrogenic, and genotoxic effects of CNF, SWCNT, or asbestos in mice 1 yr after pharyngeal aspiration. In addition, we compared pulmonary responses to SWCNT by bolus dosing through pharyngeal aspiration and inhalation 5 h/day for 4 days, to evaluate the effect of dose rate. The aspiration studies showed that these particles can be visualized in the lung at 1 yr postexposure, whereas some translocate to lymphatics. All these particles induced chronic bronchopneumonia and lymphadenitis, accompanied by pulmonary fibrosis. CNF and asbestos were found to promote the greatest degree of inflammation, followed by SWCNT, whereas SWCNT were the most fibrogenic of these three particles. Furthermore, SWCNT induced cytogenetic alterations seen as micronuclei formation and nuclear protrusions in vivo. Importantly, inhalation exposure to SWCNT showed significantly greater inflammatory, fibrotic, and genotoxic effects than bolus pharyngeal aspiration. Finally, SWCNT and CNF, but not asbestos exposures, increased the incidence of K-ras oncogene mutations in the lung. No increased lung tumor incidence occurred after 1 yr postexposure to SWCNT, CNF, and asbestos. Overall, our data suggest that long-term pulmonary toxicity of SWCNT, CNF, and asbestos is defined, not only by their chemical composition, but also by the specific surface area and type of exposure.
Journal of Occupational and Environmental Medicine | Year: 2011
Objective: Nanotechnology is the manipulation of matter on a near-atomic scale to produce nanoparticles with unique properties, allowing newcommercial applications. Since nanoparticles exhibit unique physicochemical properties, they are likely to exhibit biological activity significantly different from fine-sized particles of the same chemical composition. Therefore, evaluation of the biological effects of nanoparticles is critical. Methods: The article lists the major objectives of nanotoxicology and briefly reviews the literature concerning biological responses to pulmonary exposure. Results: Interactions of nanoparticles with biological systems depend on particle size, shape, oxidant generation, surface functionalization, and rate of dissolution. Pulmonary, cardiovascular, and central nervous system responses to pulmonary exposure to nanotitanium dioxide and carbon nanotubes are described. Conclusions: Significant biological responses occur in animal models after pulmonary exposure to certain nanoparticles. Control of exposure appears prudent to protect worker health. Clinical Significance: Nanotechnology is synthesizing a wide range of nanoparticles, which exhibit unique physicochemical properties. These unique properties make unique biological activity likely. If certain nanoparticles induce adverse effects in vitro or in animal models, then occupational health surveillance and exposure control may be prudent steps in the protection of worker health. Copyright © 2011 by American College of Occupational and Environmental Medicine.