Phosgene was still stockpiled in military arsenals well after the Second World War, but its continued presence in the atmosphere today is due to man-made chlorinated hydrocarbons used in the chemical industry.
A team, including Professor Peter Bernath, of the Department of Chemistry at the University of York, has carried out the first study of the global distribution of the gas. The team also involved scientists from the Universities of Waterloo and Toronto in Canada, NASA’s Jet Propulsion Laboratory and the New Mexico Institute of Mining and Technology in the USA.
Between February 2004 and May 2006, they used the Canadian Atmospheric Chemistry Experiment (ACE) satellite to measure the incidence of the gas. The research, which was financed by the Canada Space Agency (CSA) and the Natural Sciences and Engineering Research Council of Canada, is published in the latest edition of Geophysics Research Letters.
The scientists discovered that the main atmospheric concentration of the gas was above the Equator, though it was present in some quantity in all latitudes. They found that levels of phosgene in the atmosphere had reduced since previous studies in the 1980s and 1990s, though its continued presence is a contributor to ozone depletion.
Phosgene plays a major role in the preparation of pharmaceuticals, herbicides, insecticides, synthetic foams, resins and polymers, though its use is being reduced.
Professor Bernath said: ”There is a small, but not negligible, concentration of phosgene in the troposphere. Chlorinated hydrocarbons don't occur in nature but as chlorinated solvents they are used by industry. They are short-lived and they decay rapidly, but they decay into phosgene.
“It's very toxic and pretty nasty stuff - its reputation is well deserved. Considering the health hazards associated with phosgene, the chemical industry is trying to find substitutes to eliminate its use. But the use of chlorinated hydrocarbons is being reduced because of the legal restrictions of the Montreal Protocol, so phosgene is also decreasing.”
Higher up in the atmosphere phosgene can be slowly oxidized by ultraviolet rays, and so it continues to play a role in the depletion of the ozone layer.
David Garner | alfa
Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University
Climate change: Urban trees are growing faster worldwide
13.11.2017 | Technische Universität München
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
23.11.2017 | Information Technology
23.11.2017 | Physics and Astronomy
23.11.2017 | Life Sciences