Tag Archives: CDC

Disinfectants without chemicals for the food industry

Michael Berger in his March 16, 2015 Nanowerk Spotlight article profiles some very interesting research into replacing chemicals with water nanostructures,

The burden of foodborne diseases worldwide is huge, with serious economic and public health consequences. The CDC [US Centers for Disease Control] estimates that each year in the USA approximately 48 million people get sick, 128,000 get hospitalized and 3,000 die from the consumption of food contaminated with pathogenic microorganisms. The food industry is in search of effective intervention methods that can be applied from ‘farm to fork’ to ensure the safety of the food chain and be consumer and environment friendly at the same time.

In the food industry, chemicals are routinely used to clean and disinfect product contact surfaces as well as the outer surface of the food itself. These chemicals provide a necessary and required step to ensure that the foods produced and consumed are as free as possible from microorganisms that can cause foodborne illness.

Food activists are concerned that some of the chemicals used by the food industry for disinfection can cause health issues for consumers. A prime example is the current discussion in Europe about ‘American chlorine chicken’. …

Berger goes on to highlight the research being conducted at the Harvard T. Chan School of Public Health (Harvard University). The team announced a new technique called Engineered Water Nanostructures (EWNS), which is generated by electrospraying water. The team published this paper in 2014,

A chemical free, nanotechnology-based method for airborne bacterial inactivation using engineered water nanostructures by Georgios Pyrgiotakis, James McDevitt, Andre Bordini, Edgar Diaz, Ramon Molina, Christa Watson, Glen Deloid, Steve Lenard, Natalie Fix, Yosuke Mizuyama, Toshiyuki Yamauchi, Joseph Brain and Philip Demokritou. Environ. Sci.: Nano, 2014,1, 15-26 DOI: 10.1039/C3EN00007A

First published online 28 Nov 2013

This paper is open access.

More recently, the team has proved the efficacy of this technique on stainless steel surfaces and tomatoes. A Feb. 25, 2015 Harvard T. Chan School of Public Health news release provides information about the costs of foodborne diseases and goes on to describe the technique and the latest experiments,

The burden of foodborne diseases worldwide is huge, with serious economic and public health consequences. The U.S. Department of Agriculture’s (USDA’s) Economic Research Service reported in 2014 that foodborne illnesses are costing the economy more than $15.6 billion and about 53,245 Americans visit the hospital annually due to foodborne illnesses. The food industry is in search of effective intervention methods that can be applied form “farm to fork” to ensure the safety of the food chain and be consumer and environment friendly at the same time.

Researchers at the Center for Nanotechnology and Nanotoxicology of the Harvard T. Chan School of Public Health are currently exploring the effectiveness of a nanotechnology based, chemical free, intervention method for the inactivation of foodborne and spoilage microorganisms on fresh produce and on food production surfaces. This method utilizes Engineered Water Nanostructures (EWNS) generated by electrospraying of water. EWNS possess unique properties; they are 25 nm in diameter, remain airborne in indoor conditions for hours, contain Reactive Oxygen Species (ROS), have very strong surface charge (on average 10e/structure) and have the ability to interact and inactivate pathogens by destroying their membrane.

In a study funded by the USDA and just published this week in the premier Environmental Science and Technology journal, the efficacy of these tiny water nanodroplets, in inactivating representative foodborne pathogens such as Escherichia coli, Salmonella enterica and Listeria innocua, on stainless steel surfaces and on tomatoes, was assessed showing significant log reductions in inactivation of select food pathogens. These promising results could open up the gateway for further exploration into the dynamics of this method in the battle against foodborne disease. More importantly this novel, chemical-free, cost effective and environmentally friendly intervention method holds great potential for development and application in the food industry, as a ‘green’ alternative to existing inactivation methods.

Here’s a link to and a citation for the latest paper,

Inactivation of Foodborne Microorganisms Using Engineered Water Nanostructures (EWNS) by Georgios Pyrgiotakis, Archana Vasanthakumar, Ya Gao, Mary Eleftheriadou, Eduardo Toledo, Alice DeAraujo, James McDevitt, Taewon Han, Gediminas Mainelis, Ralph Mitchell, and Philip Demokritou. Environ. Sci. Technol., Article ASAP DOI: 10.1021/es505868a Publication Date (Web): February 19, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall. The researchers have made this image illustrating a ‘water shell’s’ effect on a bacterium located on a tomato,

Courtesy: Researchers and the American Chemical Society

Courtesy: Researchers and the American Chemical Society

I’m not sure how chemical companies are going to feel but this is very exciting news. Still, one has to wonder just how much water this technique would require for full scale adoption and would it be reusable?

US National Institute of Occupational Health and Safety sets recommendations for workplace exposure to carbon nanofibers/nanotubes

Earlier this week, the US National Institute of Occupational Health and Safety (NIOSH) set recommendations for workplace exposure to carbon nanotubes and carbon nanofibers. According to the Apr. 24, 2013 media advisory from the US Centers for Disease Control and Prevention (NIOSH’s parent agency), the recommendations have been issued in the new Current Intelligence Bulletin (CIB) no. 65. From CIB No. 65,

NIOSH is the leading federal agency conducting research and providing guidance on the occupational safety and health implications and applications of nanotechnology. As nanotechnology continues to expand into every industrial sector, workers will be at an increased risk of exposure to new nanomaterials. Today, nanomaterials are found in hundreds of products, ranging from cosmetics, to clothing, to industrial and biomedical applications. These nanoscale-based products are typically called “first generation” products of nanotechnology. Many of these nanoscale-based products are composed of engineered nanoparticles, such as metal oxides, nanotubes, nanowires, quantum dots, and carbon fullerenes (buckyballs), among others. Early scientific studies have indicated that some of these nanoscale particles may pose a greater health risk than the larger bulk form of these materials.

Results from recent animal studies indicate that carbon nanotubes (CNT) and carbon nanofibers (CNF) may pose a respiratory hazard. CNTs and CNFs are tiny, cylindrical, large aspect ratio, manufactured forms of carbon. There is no single type of carbon nanotube or nanofiber; one type can differ from another in shape, size, chemical composition (from residual metal catalysts or functionalization of the CNT and CNF) and other physical and chemical characteristics. Such variations in composition and size have added to the complexity of understanding their hazard potential. Occupational exposure to CNTs and CNFs can occur not only in the process of manufacturing them, but also at the point of incorporating these materials into other products and applications. A number of research studies with rodents have shown adverse lung effects at relatively low-mass doses of CNT and CNF, including pulmonary inflammation and rapidly developing, persistent fibrosis. Although it is not known whether similar adverse health effects occur in humans after exposure to CNT and CNF, the results from animal research studies indicate the need to minimize worker exposure.

This NIOSH CIB, (1) reviews the animal and other toxicological data relevant to assessing the potential non-malignant adverse respiratory effects of CNT and CNF, (2) provides a quantitative risk assessment based on animal dose-response data, (3) proposes a recommended exposure limit (REL) of 1 μg/m3 elemental carbon as a respirable mass 8-hour time-weighted average (TWA) concentration, [emphasis mine] and (4) describes strategies for controlling workplace exposures and implementing a medical surveillance program. The NIOSH REL is expected to reduce the risk for pulmonary inflammation and fibrosis. However, because of some residual risk at the REL and uncertainty concerning chronic health effects, including whether some types of CNTs may be carcinogenic, continued efforts should be made to reduce exposures as much as possible.

The recommended exposure, for those of us who can’t read the technical notation, translates to one microgram per cubic meter per eight-hour workday.  In other words, almost zero. Note that this is a recommendation and not a regulation. H/T Apr. 26, 2013 article by Elizabeth Wiese for USA Today

My Mar. 12, 2013 posting highlights some of the NIOSH research which preceded this recommendation.

Micro needle patches project gets Grand Challenges Explorations grant

The project being funded with a Grand Challenges Explorations grant (from the Bill & Melinda Gates Foundation) reminds me a lot of the nanopatch that Mark Kendall and his team have been developing in Australia (a project last mentioned in my Aug. 3, 2011 posting). This new initiative comes from the Georgia Institute of Technology and is aimed at the eradication of polio. From the Nov. 7, 2011 news item on Nanowerk,

The Georgia Institute of Technology will receive funding through Grand Challenges Explorations, an initiative created by the Bill & Melinda Gates Foundation that enables researchers worldwide to test unorthodox ideas that address persistent health and development challenges. Mark Prausnitz, Regents’ professor in Georgia Tech’s School of Chemical and Biomolecular Engineering, will pursue an innovative global health research project focused on using microneedle patches for the low-cost administration of polio vaccine through the skin in collaboration with researchers Steve Oberste and Mark Pallansch of the US Centers for Disease Control and Prevention (CDC).

The goal of the Georgia Tech/CDC project is to demonstrate the scientific and economic feasibility for using microneedle patches in vaccination programs aimed at eradicating the polio virus. Current vaccination programs use an oral polio vaccine that contains a modified live virus. This vaccine is inexpensive and can be administered in door-to-door immunization campaigns, but in rare cases the vaccine can cause polio. There is an alternative injected vaccine that uses killed virus, which carries no risk of polio transmission, but is considerably more expensive than the oral vaccine, requires refrigeration for storage and must be administered by trained personnel. To eradicate polio from the world, health officials will have to discontinue use of the oral vaccine with its live virus, replacing it with the more expensive and logistically-complicated injected vaccine.

Prausnitz and his CDC collaborators believe the use of microneedle patches could reduce the cost and simplify administration of the injected vaccine.

Iwonder if this team working at the microscale rather than the nanoscale, as Kendall’s team does, is finding some of the same benefits, from my August 3, 2011 posting,

Early stage testing in animals so far has shown a Nanopatch-delivered flu vaccine is effective with only 1/150th of the dose compared to a syringe and the adjuvants currently required to boost the immunogenicity of vaccines may not be needed. [emphases mine]

I find the notion that only 1/150th of a standard syringe dosage can be effective quite extraordinary. I wonder if this will hold true in human clinical trials.

If they get similar efficiencies at the microscale as they do at the nanoscale, the expense associated with vaccines using killed viruses should plummet dramatically. I do have one thought, do we have to eradicate the polio virus in a ‘search and destroy mission’? Couldn’t we learn to live with them peacefully while discouraging their noxious effects on our own biology?