(Redirected from SVGS)
The environmental chemistry and ecotoxicology of persistent organic pollutants (POPs) are fascinating areas of scientific research. Our objective in this paper is to provide a brief, focussed overview of what constitutes a POP, highlight the harmful effects they may have on biota, make some comments on their environmental sources and analysis, their environmental trends and processes, their. P53 has pleiotropic functions including control of genomic plasticity and integrity. Here we report that p53 can bind to several transcription factor IIH–associated factors, including transcription–repair factors, XPD (Rad3) and XPB, as well as CSB involved in strand–specific DNA repair, via its C–terminal domain. We also found that wild–type, but not Arg273His mutant p53 inhibits. On the basis of the previous publications, our new data and the existing scientific literature, we have formulated some fundamental principles that characterize the pivotal roles of the biodiversity of filter-feeders in ecosystems. Among those roles are: (1) the role of ecological repair of water quality, (2) the role of contributing to reliability and stability of the functioning of the. To draw the balance of anthropogenic 129 I input into European soils, the concentrations of 129 I and 127 I in seven soils from Lower Saxony were analyzed down to a depth of 250 cm. In comparison with pre-nuclear soils and Ukrainian soils, we detected a significant anthropogenic input of 129 I. Considering the different time periods for the input of 129 I and 127 I it was possible to assess. Metal contamination issues are becoming increasingly common in India and elsewhere, with many documented cases of metal toxicity in mining industries, foundries, smelters, coal-burning power plants and agriculture. Heavy metals, such as cadmium, copper, lead, chromium and mercury are major environmental pollutants, particularly in areas with high anthropogenic pressure.
Shenandoah Valley Governor's School | |
---|---|
The SVGS logo is a form of the Sierpinski triangle. | |
Address | |
, 22939 | |
Information | |
Type | Magnet school |
Established | 1993 |
School district | Augusta County Public Schools |
Director | Lee Ann Whitesell |
Grades | 11-12 |
Number of students | 175 |
Color(s) | Teal, purple |
Website | Shenandoah Valley Governor's School |
The Shenandoah Valley Governor's School is one of Virginia's 18 state-initiated magnetGovernor's Schools. It is a part-time school where 11th and 12th grade students take advanced classes in the morning (receiving their remaining classes from their home high school).
Curriculum[edit]
There are two curricula at SVGS:
The curriculum for the Math Science and Technology program includes the following college prep and dual enrollment classes: Research and Engineering, Robotics, Advanced Technology, Astrophysics, AP Computer Science, Pre Calculus, AP Calculus, DE Calculus, DE Discrete Mathematics, AP Statistics, DE Molecular Biology, AP Environmental Science, DE Environmental Chemistry, DE Physics, and Modern Physics.
The curriculum for the Arts and Humanities program includes DE Acting I (through JMU), Acting II, DE Introduction to Theatre (through JMU), Advanced Dramatic Theories and Criticism, advanced art classes, DE Humanities 111/112, DE Communication, DE Psychology, and DE The Humanities in Western Culture (through BRCC).
Contributing schools[edit]
Extracurricular activities[edit]
- Electric Vehicle Team
- Robotics Team
- Network Team
- Envirothon Team
- Outreach (with elementary and middle schoolers)
External links[edit]
Coordinates: 38°6′55.8″N78°59′20″W / 38.115500°N 78.98889°W
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Shenandoah_Valley_Governor%27s_School&oldid=991246995'
General structure of polychlorinated naphthalenes
A K De Environmental Chemistry Pdf Textbook
Structure of 2,3,6,7-Tetrachloronaphthalene
Polychlorinated naphthalene (PCN) are the products obtained upon treatment of naphthalene with chlorine. The generic chemical formula is C10H8−(m+n)Cl(m+n). Commercial PCNs are mixtures of up to 75 components and byproducts.[1] The material is an oil or a waxy solid, depending on the degree of chlorination. PCNs were once used in insulating coatings for electrical wires, as well as other applications, but their use has been largely phased out.[2]
Production[edit]
PCNs started to be produced for high-volume uses around 1910 in both Europe and the United States.[2][3] In Europe the largest volume products were called Nibren waxes, made in Germany by Bayer. Other European PCN tradenames included Seekay (UK, from ICI), Clonacire (France), Cerifal (Italy) and Woskol (Poland). In the United States, the largest volume PCN products were called Halowax, from a New York company of the same name that was later owned by Union Carbide and then taken over by Koppers of Pittsburgh, PA, now Beazer East. Although trace amounts of PCNs may be released by natural processes such as wildfires, their industrial uses increased the apparent rates of accumulation in the environment by factors of 10,000 or more.[4]
Safety[edit]
After about twenty years of commercial production, health hazards began to be reported in workers exposed to PCNs: chloracne,[1] severe skin rashes[5] and liver disease that led to deaths of workers.[6][7] A conference about the hazards was organized at Harvard School of Public Health in 1937, and several more publications dealing with PCN hazards appeared before 1940.[8] PCNs containing three or more chlorines per molecule have typically been found more hazardous than those with fewer,[9] but as the maximum of eight is approached, hazards appear to decrease.[10]
There was a lag of about forty years between disclosure of PCN hazards and government regulation. In the U.S. exposure to PCNs was drastically reduced after 1976, following enactment of the Toxic Substances Control Act. Major equipment manufacturers banned PCNs in their products, and major PCN producers discontinued operations. By 1983 worldwide PCN production had almost halted except for small amounts used in testing and research. Until recent years duPont produced a synthetic rubber, Neoprene FB, made in Northern Ireland using pentachloronaphthalene.[11] Today PCNs are offered commercially by only a few companies, including Ukrgeochem of Simferopol, Ukraine.
Increased cancer risks have been suspected but so far not shown. Current concerns about PCNs include their release as byproducts of waste incineration.[12]
Bioaccumulation[edit]
In 2013, the 9th meeting of the Persistent Organic Pollutants Review Committee, established under the Stockholm Convention on Persistent Organic Pollutants proposed di-,tri-,tetra-,penta-,hexa-, hepta- and octa-chlorinated napthalenes, for listing in Annexes A and C to that Convention.[13]
While some PCNs can be broken down by sunlight and, at slow rates, by certain microorganisms, many PCNs persist in the environment. After more than 80 years of use and total production of several hundred thousand tons, PCN residues are widespread.[10]
See also[edit]
References[edit]
A K De Environmental Chemistry Pdf Class 11
- ^ abvan de Plassche, E.; Schwegler, A. (2002). Polychlorinated naphthalenes, Preliminary Risk Profile.Ministry of VROM/DGM, Netherlands
- ^ abRossberg, Manfred; Lendle, Wilhelm; Pfleiderer, Gerhard; Tögel, Adolf; Dreher, Eberhard-Ludwig; Langer, Ernst; Rassaerts, Heinz; Kleinschmidt, Peter; Strack, Heinz; Cook, Richard; Beck, Uwe; Lipper, Karl-August; Torkelson, Theodore R.; Löser, Eckhard; Beutel, Klaus K.; Mann, Trevor (2006). 'Ullmann's Encyclopedia of Industrial Chemistry - Chlorinated Hydrocarbons'. doi:10.1002/14356007.a06_233.pub2. ISBN3527306730.Cite journal requires
|journal=
(help) - ^Chlorinated naphthalenesArchived 2005-07-18 at the Wayback Machine, Chemical Assessment Report S48, 2002, National Industrial Chemicals Notification and Assessment Scheme
- ^Horii, Y.; Falandysz, J.; Hanari, N.; Rostkowski, P. (2004). 'Concentrations and fluxes of chloronaphthalenes in sediment from Lake Kitaura in Japan in past 15 centuries'(PDF). Journal of Environmental Science and Health, Part A. 39 (3): 587. doi:10.1081/ESE-120027727.[permanent dead link]
- ^Teleky, L. (1927). 'Die pernakrankheit'. Klinische Wochenschrift. 6: 845. doi:10.1007/bf01728520.
- ^Flinn, F.B.; Jarvik, N.E. (1936). 'Action of certain chlorinated naphthalenes on the liver'. Proceedings of the Society for Experimental Biology and Medicine. 35: 118. doi:10.3181/00379727-35-8879p.
- ^Chronic exposure increases risk of liver disease. See Chlorinated naphthalenes exposure, Worker Notification Program, National Institute for Occupational Safety and Health
- ^Butler, D.A. (2005). 'The early history of scientific and medical research on 'agent orange''(PDF). Brooklyn Journal of Law and Policy. 13 (2): 531–533. Archived from the original(PDF) on 2006-09-02.
- ^Drinker, C.K.; Warren, M.F.; Bennet, G.A. (1937). 'The problem of possible systemic effects from certain chlorinated hydrocarbons'. Journal of Industrial Hygiene and Toxicology. 19 (7): 283.
- ^ abChlorinated naphthalenes, International Programme on Chemical Safety CICAD, 2001, volume 34
- ^Neoprene FBArchived 2007-09-27 at the Wayback Machine, Material Safety Data Sheet, DuPont de Nemours & Co., 1985
- ^Omura, M.; Masuda, Y.; Hirata, M.; Tanaka, A. (2000). 'Onset of spermatogenesis is accelerated by gestational administration of 1,2,3,4,6,7-hexachlorinated naphthalene in male rat offspring'(PDF). Environmental Health Perspectives. 108 (6): 539–544. doi:10.2307/3454616. JSTOR3454616. PMC1638139. PMID10856028. Archived from the original(PDF) on 2010-06-02.
- ^UNEP (2013). Risk management evaluation on chlorinated naphthalenes, Report of the Persistent Organic Pollutants Review Committee on the work of its ninth meeting, Rome, 14–18 October 2013 (Addendum)
Literature[edit]
- Eva Jakobsson, Lillemor Asplund: Polychlorinated Naphthalenes (PCNs), in The Handbook of Environmental Chemistry, Volume 3K, 2000, p. 97–126, ISBN978-3-540-65838-2, doi:10.1007/3-540-48915-0_5
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Polychlorinated_naphthalene&oldid=920784456'