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Michael R. Flynn1,* and Pam Susi2

1Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599-7431, USA

2Center for Construction Research and Training, 8484 Georgia Avenue, Suite 1000, Silver Spring, MD 20910, USA ?* Author to whom correspondence should be addressed. Tel: +919-966-3473; fax: +919-966-7911; e-mail: Mike_flynn{at}unc.edu Received November 18, 2011. Accepted January 16, 2012. Arc welding is a common unit operation in the construction industry, where frequent changes in location and welding position make it more difficult to control fume exposures than in industries where fixed locations are the norm. Welders may be exposed to a variety of toxic airborne contaminants including manganese (Mn) and hexavalent chromium (CrVI). Local exhaust ventilation (LEV) is a well-known engineering control for welding fumes but has not been adopted widely in the construction industry. This literature review presents data on the performance of a variety of LEV systems for welding fume control from the construction (five references), shipyard (five references), and other industries. The studies indicate that LEV can reduce fume exposures to total particulate, Mn, and CrVI to levels below currently relevant standards. Field studies suggest that 40–50% or more reduction in exposure is possible with portable or fixed LEV systems relative to natural ventilation but that correct positioning of the hood and adequate exhaust flow rates are essential. Successful implementation of extraction guns for gas metal arc welding (GMAW) and flux core arc welding has been demonstrated, indicating that a successful balance between extraction airflow and shielding gas requirements is possible. Work practices are an important part of achieving successful control of fume exposures; in particular, positioning the hood close to the arc, checking exhaust flow rates, and avoiding the plume. Further research is needed on hood size effects for controlling welding fume with portable LEV systems and identifying and overcoming barriers to LEV use in construction.

© The Author 2012. Published by Oxford University Press on behalf of the British Occupational Hygiene SocietyThis ArticleAnn Occup Hyg (2012) 56 (7): 764-776. doi: 10.1093/annhyg/mes018 First published online: March 29, 2012 Current Issue The Annals of Occupational Hygiene

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Control Banding Approaches for Nanomaterials

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DERK H BROUWER*

TNO Research Group Quality and Safety PO Box 360, 3700 AJ Zeist Netherlands ?* Author to whom correspondence should be addressed. E-mail: dick.brouwer{at}tno.nlReceived April 28, 2012. Accepted April 18, 2012. Control banding (CB) has been developed as a pragmatic tool to manage the risk resulting from exposure to a wide variety of potentially hazardous substances in the absence of firm toxicological and exposure information. Currently, the CB approach is applied for emerging risks such as nanoparticles, by the development of various CB-based tools. Six of these are compared. Despite their similarity, i.e. combining hazard and exposure into control or risk bands, the structure, the applicability domains, and the assignment of the hazard and exposure bands, show differences that may affect the consistency of the resulting outcome amongst the various CB tools. The value of the currently available CB tools for nanomaterials can be enhanced by transparently elucidating these differences for user consideration during the selection of a tool for a specific scenario of application.

Keywords: © The Author 2012. Published by Oxford University Press on behalf of the British Occupational Hygiene SocietyThis ArticleAnn Occup Hyg (2012) 56 (5): 506-514. doi: 10.1093/annhyg/mes039 Current Issue The Annals of Occupational Hygiene

Risks and Control of Nanomaterials

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TREVOR OGDEN*

British Occupational Hygiene Society, Melbourne Business Court, Derby DE24 8LZ, UK ? *Author to whom correspondence should be addressed. +44 1332 298101 ogden{at}ogs.org.uk Received April 28, 2012. Revision received April 20, 2012. Accepted April 20, 2012. In this issue we bring together 12 articles on
nanomaterials and approaches to risk control. The issue opens with a review by Eileen Kuempel and colleagues of the research needs for effective management of these materials. This is followed by
two items on tools for control: a review of control banding and a report of discussions on reference values. Then an article describes the development of a practical generic approach to control, applying the popular tool Stoffenmanager to nanoparticles.

After this come two articles on exposure: one in the new field of manufacture of nanotubes …
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Tuesday, October 23, 2012

Nearly half of U.S. adults with high blood pressure have it under control

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ScienceDaily (Oct. 22, 2012) — Nearly half of U.S. adults with high blood pressure had their blood pressure under control by the end of 2010 -- a significant increase from the start of the decade, researchers reported in the American Heart Association journal Circulation.

Improvements in blood pressure control were most likely due to wider use of multiple drug combinations , researchers said.

Researchers at the National Center for Health Statistics (NCHS) interviewed 9,320 hypertensive participants in the National Health and Nutrition Examination Survey (NHANES) 2001-10. By the end of 2010, 47 percent had controlled blood pressure -- up from 29 percent 10 years earlier.

The in-person survey is the first to compare blood pressure control rates before and after the Joint National Committee (JNC7) treatment guidelines were published in 2003.

Under JNC7 guidelines, many patients may need combination therapy with two or more drugs to achieve adequate blood pressure control.

In the study, almost two-thirds of those on combination therapy had controlled blood pressure by 2010, and the use of multiple drugs increased from 37 percent in 2001 to 48 percent by 2010.

Compared with using one drug, single and multiple-pill combinations were associated with 55 percent and 26 percent increased likelihood of control, respectively.

"Much progress has been made in blood pressure control over the last 10-year period and the use of multiple drug combinations apparently has had an effect," said Qiuping Gu, M.D., Ph.D., an epidemiologist at the NCHS.

Lower cost of medications and their availability in generic form as well as increased awareness of the risk of uncontrolled high blood pressure has also had a positive effect.

But some issues continue to be problematic, researchers said.

The national hypertension treatment guidelines recommended thiazide diuretics as initial drug therapy for most patients with uncomplicated hypertension, yet their overall use remains comparatively low. In addition, "nearly half of the hypertensive population is not being treated with combination therapy," said Charles F. Dillon, M.D., Ph.D., co-author of the study.

Moreover, rates were lower for older Americans, African-Americans and people with diabetes and chronic kidney disease. Mexican-Americans were least likely to take any kind of blood pressure medication.

"While there are possibly several factors involved, more needs to be learned about why only 34 percent of Mexican-Americans with hypertension have their blood pressure under control," Gu said. Participants were only asked about medications used in the prior month, so those who might have taken medications previously were classified as non-users.

Furthermore, NHANES blood pressure measurements were only collected one time, so some people in the study may have been misclassified.

Other co-authors are: Vicki L. Burt, Sc.M., R.N.; Charles F. Dillon, M.D., Ph.D.; and Sarah Yoon, Ph.D. Author disclosures are on the manuscript.

NCHS is part of the U.S. Centers for Disease Control and Prevention.

For high blood pressure information visit www.heart.org/hbp .

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The above story is reprinted from materials provided by American Heart Association.
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Journal Reference:

Q. Gu, V. L. Burt, C. F. Dillon, S. Yoon. Trends in Antihypertensive Medication Use and Blood Pressure Control Among United States Adults With Hypertension: The National Health and Nutrition Examination Survey, 2001 to 2010. Circulation, 2012; 126 (17): 2105 DOI: 10.1161/CIRCULATIONAHA.112.096156

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Eating more legumes may improve glycemic control, lower estimated heart disease risk

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ScienceDaily (Oct. 22, 2012) — Eating more legumes (such as beans, chickpeas or lentils) as part of a low-glycemic index diet appears to improve glycemic control and reduce estimated coronary heart disease (CHD) risk in patients with type 2 diabetes mellitus (DM), according to a report of a randomized controlled trial published Online First by Archives of Internal Medicine, a JAMA Network publication.

Low glycemic index (GI) foods have been associated with improvement in glycemic control in patients with type 2 (DM) and have been recommended in many national DM guidelines, the authors write in the study background.

David J.A. Jenkins, M.D., of the University of Toronto and St. Michael's Hospital,Toronto,Canada, and colleagues conducted a randomized controlled trial of 121 patients with type 2 DM to test the effect of eating more legumes on glycemic control, serum (blood) lipid levels and blood pressure (BP).

Patients were randomized to either a low-GI legume diet that encouraged patients to increase eating legumes by at least one cup a day or to increase insoluble fiber by eating whole wheat products for three months. Changes in hemoglobin A1c (HbA1c) values were the primary outcome measure and calculated CHD risk score was the secondary outcome.

"In conclusion, legume consumption of approximately 190 g per day (1 cup) seems to contribute usefully to a low-GI diet and reduce CHD risk through a reduction in BP," the authors note.

The low-GI legume diet reduced HbA1c values by -0.5 percent and the high wheat fiber diet reduced HbA1c values by -0.3 percent. The respective CHD risk reduction on the low-GI legume diet was -0.8 percent, largely because of a greater relative reduction in systolic blood pressure on the low-GI legume diet compared with the high wheat fiber diet (-4.5 mm Hg), the study results indicate.

"These findings linking legume consumption to both improved glycemic control and reduced CHD risk are particularly important because type 2 DM is increasing most rapidly in the urban environments of populations in which bean intake has traditionally been high (e.g. India, Latin America, the Pima Indians of Arizona)," the authors conclude. "Support for the continued use of such foods in traditional bean-eating communities, together with their reintroduction into the Western diet, could therefore be justified even if the effect on glycemia is relatively small, given the magnitude of the problem and the need for acceptable dietary options, especially those options that may also have a BP and cardiovascular advantage."

Commentary: Diabetes Nutrition Therapy

In an invited commentary, Marion J. Franz, M.S., R.D., C.D.E, Nutrition Concepts by Franz Inc., Minneapolis, Minn., writes: "The importance of the glycemic index (GI) and fiber in diabetes mellitus (DM) nutrition therapy has been controversial."

"Legumes, as documented in the study by Jenkins et al, are components of a healthy eating pattern for people with DM and the general public. Whether people with DM can eat the amount necessary to improve glycemic control is debatable, and, if legumes do improve glycemia, is it because of their low GI or high soluble fiber content?" the commentary goes on to state.

"Nutrition therapy for DM is effective. However, just as there is no one medication or insulin regimen appropriate for all persons with DM, there is no one nutrition therapy intervention. A variety of nutrition therapy interventions have been shown to be effective. Nutrition education and counseling must be sensitive to the personal needs and cultural preferences of individuals and their ability to make and sustain lifestyle changes," Franz concludes.

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The above story is reprinted from materials provided by JAMA and Archives Journals.
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Journal References:

Jenkins DA, Kendall CC, Augustin LA, et al. Effect of Legumes as Part of a Low Glycemic Index Diet on Glycemic Control and Cardiovascular Risk Factors in Type 2 Diabetes Mellitus: A Randomized Controlled Trial. Archives of Internal Medicine, 2012; DOI: 10.1001/2013.jamainternmed.70Franz MJ. Diabetes Mellitus Nutrition Therapy: Beyond the Glycemic Index. Archives of Internal Medicine, 2012; DOI: 10.1001/2013.jamainternmed.871

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Local Exhaust Ventilation for the Control of Welding Fumes in the Construction Industry--A Literature Review

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Michael R. Flynn1,* and Pam Susi2

1Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599-7431, USA

Sunday, October 21, 2012

Ultraviolet light effective in hospital infection control, study suggests

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ScienceDaily (Oct. 18, 2012) — Research being presented at IDWeek 2012™ shows that a specific spectrum of ultraviolet light killed certain drug-resistant bacteria on the door handles, bedside tables and other surfaces of hospital rooms, suggesting a possible future weapon in the battle to reduce hospital-associated infections.

Researchers at Duke University Medical Center and the University of North Carolina Hospital System used short-wave ultraviolet radiation (UV-C) to nearly eliminate Acinetobacter, Clostridium difficile or vancomycin-resistant enterococci (VRE) in more than 50 patient rooms at the two medical facilities.

"We're learning more and more about how much the hospital environment contributes to the spread of these organisms," said lead researcher Deverick J. Anderson, MD, an assistant professor of medicine at Duke and co-director of the Duke Infection Control Outreach Network. Given previous findings by the University of North Carolina team that UV-C is effective at decreasing methicillin-resistant Staphylococcus aureus (MRSA) in hospital rooms, he believes that the new study lays critical groundwork.

"We have a solid foundation to show that this approach succeeds in both experimental and real-world conditions," Anderson said. "Now it's time to see if we can demonstrate that it indeed decreases the rate of infections among patients."

His group's work is among the significant research being discussed at the inaugural IDWeek meeting, taking place through October 21 in San Diego. With the theme Advancing Science, Improving Care, IDWeek features the latest science and bench-to-bedside approaches in prevention, diagnosis, treatment, and epidemiology of infectious diseases, including HIV, across the lifespan. More than 1,500 abstracts from scientists in this country and internationally will be highlighted over the conference's five days.

"Healthcare-associated infections are linked with significant morbidity and mortality," said Liise-anne Pirofski, MD, an IDWeek chair for the Infectious Diseases Society of America. "Although there are multiple sources for these infections, the hospital environment itself can play an important role. The findings of this study suggest that UV light could hold promise for eliminating bacteria from hospital rooms and reducing the risk of infection with these difficult bacterial pathogens in the healthcare environment. That would be a result to benefit us all."

UV-C, which is harmful to microorganisms, has been used for decades in food, air and water purification and to sterilize equipment in laboratory settings. This study demonstrates that its medical application may offer new strategies for reducing the estimated 1.7 million hospital-associated infections that occur annually in the United States. The cost of treating these infections, often involving increasingly antibiotic-resistant bacteria, ranges from an estimated $4.5 billion to as much as $11 billion.

In their study, the Duke and University of North Carolina researchers questioned whether UV-C could be utilized to eliminate three of the most problematic germs and improve the cleanliness of patient rooms. Given the tough economics of healthcare today, hospitals' environmental services are under pressure to turn rooms over quickly, and many surfaces can get missed by even the most diligent crews.

The study focused on general-medical and intensive-care units of the two medical centers and identified patients with infections from the targeted bacteria. Clostridium difficile, or C. diff as it is commonly known, can trigger serious intestinal conditions. Acinetobacter can cause pneumonia and serious blood, wound and urinary tract infections. VRE most frequently infects the urinary tract, bloodstream, wounds or catheter sites. Each bacterium can survive for prolonged periods on surfaces.

After the patients were discharged, the researchers obtained multiple cultures from each of five specific locations in the hospital rooms and bathrooms -- "high-touch" areas that included bed rails, remote controls and toilets. A special machine with eight UV bulbs mounted on a central column was then positioned strategically in each room and turned on for as long as 45 minutes to eradicate both vegetative bacteria and bacterial spores. Fifteen more cultures were taken from the same locations in every room, and the pre- and post-treatment bacteria counts were compared.

The numbers of bacterial CFUs, or colony-forming units, fell precipitously. Fifty-two CFUs of Acinetobacter were seen before irradiation, but only 1 CFU afterward -- down 98.1 percent. As for VRE, the proportion decrease was nearly the same -- 719 CFUs before and 15 after, a 97.9 percent drop.

The culturing initially was not sensitive enough to isolate C. diff, but improved techniques allowed the researchers to do further testing and the results in the UV-C treated rooms were just as dramatic.

"We would never propose that UV light be the only form of room cleaning, but in an era of increasing antibiotic resistance, it could become an important addition to hospitals' arsenal," Anderson said.

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IUDs Increasingly Popular Form of Birth Control

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By Rita Rubin
WebMD Health News

Reviewed by Louise Chang, MD

Oct. 18, 2012 -- While the use of long-acting intrauterine devices (IUDs) is increasing, 1 in 9 women at risk for unintended pregnancies is not using any birth control, according to a new government report.

Researchers from the National Center for Health Statistics, part of the CDC, analyzed data from more than 12,000 women aged 15 to 44. They compared that information with data collected from nearly 11,000 women in 1995.

Nearly two-thirds, or 62%, of women of reproductive age use contraception, with the pill preferred by 28% of women and female sterilization the choice of 27%, almost exactly the same proportions as in 1995.

Use of IUDs rose to 5.6%, seven times the .8% in 1995, an increase that James Trussell, PhD, calls "striking." Trussell is a faculty associate at Princeton University's Office of Population Research. He was not involved in the study.

Depending on the type of IUD, the devices work for five years or 10 years and are more than 99% effective in preventing pregnancy.

Earlier this month, the American Congress of Obstetricians and Gynecologists' Committee on Adolescent Health Care took a step toward clearing up the misconception that only women who've delivered children can use an IUD. The committee published an opinion paper concluding that teens, who are at high risk of unintended pregnancy, might benefit from greater access to long-acting reversible contraceptives, namely IUDs and contraceptive implants. The implants, tiny hormone-releasing rods inserted under the skin of the arm, are more than 99% effective and can be left in place for three years.

Teens increasingly have turned to hormonal contraceptives such as the pill and away from condoms, the new report shows. Since 1995, there was a 45% decline in the use of condoms as the main form of birth control by young women 15 to 19 years old, researchers found. That change, along with the increased use of contraceptives the first time they have intercourse, and using more than one method at a time, such as the pill and condoms, have been credited with the recent decline in teen birth rates, the researchers write.

"One of the things that I was struck with was the adoption of the newer methods of birth control by the younger women and women of color," says researcher Jo Jones, PhD, a statistician and demographer at the National Center for Health Statistics. Since 1990, a number of new hormonal methods have become available. These include NuvaRing, a vaginal ring left in place for three weeks and then removed for a week, and Ortho Evra, a patch that is placed on the skin and changed weekly.

Use of IUDs and implants might continue to supplant condoms and other less-effective birth control methods, says Lawrence Finer, PhD, director of domestic research at the Guttmacher Institute, which performs research, policy analysis, and public education focused on sexual and reproductive health. "It's possible we're seeing the start of a transition here toward these more effective long-acting methods," Finer says.

In the current issue of Fertility & Sterility, Finer and his colleagues published a separate analysis of data collected in 2007-2009. Their study found that among women using birth control, the proportion who opted for an IUD or implant increased from 2.4% in 2002 to 8.5% in 2009.

SOURCES: James Trussell, PhD, faculty associate at Princeton University's Office of Population Research. Jo Jones, PhD, a statistician and demographer at the National Center for Health Statistics. Lawrence Finer, PhD, director of domestic research at the Guttmacher Institute.