Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electrons defeat anthrax

11.10.2002


Perhaps, bioterrorists will not be able to spread lethal bacteria of anthrax in envelopes all over the world. Siberian biologists and physics have thought up how to adapt electron accelerator that is usually used for sterilizing medical equipment for decontamination of letters. To optimize the power of the accelerator they calculated how many bacteria could get into a human body when touching the letter infected and how many bacteria should be destroyed to avoid the tragedy.



For their experiment the scientists chose two bacteria species that form almost ineradicable spores. Both species were genetically close to anthrax. One of them is a harmless inhabitant of soils whereas the other causes a disease in insects. Its spores in the mixture with the powdered mineral kaolin can be used as insecticide.

When imitating the probable actions of mail terrorists the scientists made 60 paper packets with the sides of 50 and 25 millimeters and poured a quarter of a gram of sterile kaolin. Then several drops of suspension, which contained 10 million spores per one milliliter, were added into each packet and intensively mixed with kaolin. Then the packets were dried at 70 C and put into envelopes.


The samples were treated with an electron beam from the industrial electron accelerator. The doses applied were varied from 1 to 400 kGy. To find out the effect from a particular dose the powder with the bacteria was dissolved in distilled water and placed in culture medium. It turned out that the dose of 10 kGy killed a lot of spores. The scientists could not find any live microbes after treating the samples with the dose of 20 kGy and the dose of 400 kGy even made the paper destroy. It became fragile.

When you touch the powder about 50 mg of kaolin may remain on your fingers. However, the skin is better protected against penetrating the infection inside in comparison with the lungs. How much kaolin with the spores can a person breathe in? To find it out the researchers tore the envelopes open, placed the powder on a platter and collected the air polluted with a pump with a filter at a height of 30 cm above the platter for a minute. The operation was repeated three times and then the quantity of kaolin on the filter was determined chemically. According to the data obtained a person can breathe in 1 - 2 thousandth of a milligram of the powder. Based on the results and the calculations, the scientists recommend irradiating the correspondence with a dose of about 50 kGy. However, to reduce the probability of infection from one letter to one case per a million the dose of 22 kGy proved to be quite sufficient. The electron accelerator, which is produced at the Budker Institute of Nuclear Physics (Novosibirsk), can be used for this purpose. The accelerator weighs about ten tons and can be placed on the area of about 50 square meters. To protect the staff from radiation the accelerator is isolated with concrete layer of one and a half meter.

Electron accelerator can sterilize relatively thin objects. That is why the letters should be placed in one layer. According to the calculations the rate of sorting will remain within the norm if the number of staff doubles or the process of sorting is automated. The sterilization of parcels seems to be more complicated task. Only dangerous sources of gamma radiation are able to solve it. However, the biologists doubt that terrorists will start using parcels for their subversive activity and believe that electron accelerator can eliminate the problem of mail terrorism sufficiently.

Alexander Barne | alfa

More articles from Health and Medicine:

nachricht Lung images of twins with asthma add to understanding of the disease
05.12.2019 | University of Western Ontario

nachricht Between Arousal and Inhibition
05.12.2019 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The coldest reaction

With ultracold chemistry, researchers get a first look at exactly what happens during a chemical reaction

The coldest chemical reaction in the known universe took place in what appears to be a chaotic mess of lasers. The appearance deceives: Deep within that...

Im Focus: How do scars form? Fascia function as a repository of mobile scar tissue

Abnormal scarring is a serious threat resulting in non-healing chronic wounds or fibrosis. Scars form when fibroblasts, a type of cell of connective tissue, reach wounded skin and deposit plugs of extracellular matrix. Until today, the question about the exact anatomical origin of these fibroblasts has not been answered. In order to find potential ways of influencing the scarring process, the team of Dr. Yuval Rinkevich, Group Leader for Regenerative Biology at the Institute of Lung Biology and Disease at Helmholtz Zentrum München, aimed to finally find an answer. As it was already known that all scars derive from a fibroblast lineage expressing the Engrailed-1 gene - a lineage not only present in skin, but also in fascia - the researchers intentionally tried to understand whether or not fascia might be the origin of fibroblasts.

Fibroblasts kit - ready to heal wounds

Im Focus: McMaster researcher warns plastic pollution in Great Lakes growing concern to ecosystem

Research from a leading international expert on the health of the Great Lakes suggests that the growing intensity and scale of pollution from plastics poses serious risks to human health and will continue to have profound consequences on the ecosystem.

In an article published this month in the Journal of Waste Resources and Recycling, Gail Krantzberg, a professor in the Booth School of Engineering Practice...

Im Focus: Machine learning microscope adapts lighting to improve diagnosis

Prototype microscope teaches itself the best illumination settings for diagnosing malaria

Engineers at Duke University have developed a microscope that adapts its lighting angles, colors and patterns while teaching itself the optimal...

Im Focus: Small particles, big effects: How graphene nanoparticles improve the resolution of microscopes

Conventional light microscopes cannot distinguish structures when they are separated by a distance smaller than, roughly, the wavelength of light. Superresolution microscopy, developed since the 1980s, lifts this limitation, using fluorescent moieties. Scientists at the Max Planck Institute for Polymer Research have now discovered that graphene nano-molecules can be used to improve this microscopy technique. These graphene nano-molecules offer a number of substantial advantages over the materials previously used, making superresolution microscopy even more versatile.

Microscopy is an important investigation method, in physics, biology, medicine, and many other sciences. However, it has one disadvantage: its resolution is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The Future of Work

03.12.2019 | Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

 
Latest News

Detailed insight into stressed cells

05.12.2019 | Life Sciences

State of 'hibernation' keeps haematopoietic stem cells young - Niches in the bone marrow protect from ageing

05.12.2019 | Life Sciences

First field measurements of laughing gas isotopes

05.12.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>