institute of environmental toxicology ibaraki

... Friends of Nature Institute of Public & Environmental Affairs Green Beagle Envirofriends Green Stone Environmental Action Network Cover Photo by Chuong Nguyen Trang 2Figure 1: Mapping of some ... Levels of Environmental Pollution According to a number of news channels, at the start of 2011, Apple finalized a second list of printed circuit board (PCB) suppliers for its second generation of ... Friend’s of Nature’s Wuhan Branch and the Institute of Public & Environmental Affairs went to the Wuhan Meiko Electronics site The lawyer Zeng Xiangbin, who is the person in charge of Friend’s of

Ngày tải lên: 29/03/2014, 14:20

... for Environmental Toxicology Environmental toxicology can be simplified to the understanding of only three functions These functions are presented in Figure 2.1 First, there is the interaction of ... functions of environmental toxicology Only three basic functions need to be described after the introduction of a xenobiotic into the environment The first describes the fate and distribution of the ... indications of the interaction of a xenobiotic with the ecosystem. The examples listed are only a selection of the parameters that need to be understood for the explanation of the effects of a xenobiotic

Ngày tải lên: 10/08/2014, 20:20

... certainthreshold concentration is reached In environmental toxicology, environmental con-centration is often used as a substitute for knowing the actual amount or dose of achemical entering an organism ... The x-axis is in units of weight to volume (concentration) or weight of toxicant per unit weight of animal (dose). Trang 4One of the primary reasons for conducting any type of toxicity test is to ... weight of toxicant per unit weight of animal (dose). Trang 5structure activity relationships Another weakness of the LC50, EC50, and IC50 is thatthey reflect the environmental concentration of the

Ngày tải lên: 10/08/2014, 20:20

... amount of time, amount of toxicant, and the cost of performing chronic-type toxicity tests. This methodology has proven useful in a variety of roles, especially in the testing of effluents. One of ... same level of standardization This is due to the length of time most of these tests require and the specialized nature of most of the test systems rather than any lack of completeness... ... group is probably the most adapted of all aquatic insects The larvae of this group are often used as an indicator of environmental quality Habitats of immatures range from littoral marine

Ngày tải lên: 10/08/2014, 20:20

... action. The effect of the pollutant, then, is a function of its concentration at the locus of its action. For this reason, any factors capable of modifying internal concentration of the chemical ... Graphical representation of the sum of toxic contributions. In the top of the figure the sum of toxic contributions is counterintuitive, the more than additive toxicity has a ratio of less than one and ... usefulness of these equations is (1) in the estimation of the toxicity of a mixture and (2) the setting of priorities for cleanup by establishing the major contributor to the toxicity of the mixture.

Ngày tải lên: 10/08/2014, 20:20

... routes Tobacco in all of its forms contains appreciable amounts of Cd, and tobacco smoke is one of the largest single sources of Cd exposure to humans Since the absorption of Cd in the lungs is ... release of acetylcholine across the synapse, this inhibition manifests itself in the form of decreased endplate potential The miniature endplate potential release of subthreshold levels of acetylcholine ... is the world’s largest producer of cadmium, with an annual output of about 5000 short tons Mexico is an important producer of Cd-bearing dusts and fumes, but most of these are smelted in the U.S

Ngày tải lên: 10/08/2014, 20:20

... 5.2). When the rate of entry is greater than the rate of metabolism and/or excretion, storage of the chemical often occurs. Storage or binding sites may not be the sites of toxic action, however. ... spectrum peak at 450 nm. This is the origin of the name of the enzyme. As a result of the complex, inhibition of the oxidation process occurs. At the active sites of cytochrome P-450 is an iron atom ... entire microbial community since often more than one type of organism is responsible for the stages of microbial degradation. Microorganisms often contain a variety of genetic information. In prokaryotic

Ngày tải lên: 10/08/2014, 20:20

... in environmental toxicology is the Index of Biotic Integrity (IBI) as developed by Karr (1991) An index such as the IBI is a means of rating the structure of a community from a one-time set of ... describing a variety of interactions in a community One of the major implications of these models is the importance of resourcesand initial conditions in the determination of the outcome of a toxicant ... the maintenance of the fish facility,manpower requirements for the culture of the test organisms, and the costs of falsepositives Again, the question of the ecological relevance of such subtle

Ngày tải lên: 10/08/2014, 20:20

... making decisions, often with a great deal of uncertainty The science of environmental toxicology, as with any science,attempts to answer specific questions In the case of environmental toxicology thequestion ... deal of environmental toxicology is performed with the eventual goal of performing a risk assessment A great deal of the research performed in the field is geared toward the determination of the ... measure of the concentrations or persistence of a stressor withinthe defined system Exposure can be expressed as a dose, but in environmentaltoxicology it is often possible to measure environmental

Ngày tải lên: 10/08/2014, 20:20

... Norton Office of Research and Donald J Rodier Office of Toxic Substances MEMBERS Office of Policy, Planning and Office of Research and DevelopmentEvaluation Office of Toxic Substances Office of Policy, ... Wood Office of Research and Development Office of Research and Development REVIEWERS U.S Environmental Protection Agency U.S Environmental Protection AgencyEnvironmental Research Laboratory Office ... Environmental Protection Agency Office of Technology Transfer and U.S Environmental Protection Agency U.S Environmental Protection AgencyOffice of Pesticide Programs Office of Pesticide Programs PEER

Ngày tải lên: 10/08/2014, 20:20

... term toxicology or have an understanding of its concepts So what is a good definition of toxicity? It can be best defined as the science of poisons Of course, this brings us to the question of ... substance AREAS OF TOXICOLOGY Toxicology can be divided into a variety of subareas These areas can be categorized by organ systems, chemicals (substances), or discipline Examples of categorization ... common references on environmental and occupational toxicology Klaassen CD (1996), Casarett and Doulls Toxicology: the basic science of poisons An excellent reference on toxicology, although

Ngày tải lên: 10/08/2014, 20:20

... Furthermore, consumption of crude oil has also increased, with the average rate of increase of 6% per year in the past decades Part of this increase is the result of the growing use of motor vehicles, ... U.S between 1950 and 2000 Rank Year Cause of death % a Cause of death % a Cause of death % a 1 Disease of heart 40.5 Disease of heart b 39.6 Disease of heart b 29.6 2 Malignant neoplasm 13.4 ... by-product of these actions was one of the greatest environmental success stories of the 20th century Today, the Hudson produces more fish per hectare than most other major estuaries of the North

Ngày tải lên: 11/08/2014, 13:22

... composed of the gaseous products of burning carbonaceous materials made visible by the presence of small particles of carbon The brownish to blackish materials emitted from the stack of an inadequately ... in the city of Poza Rica, Mexico, in the early morning of November 24, 1950, was caused by the accidental release of H2S from a natural gas plant At the time of the accident, most of the nearby ... attempt to reduce environmental pollution Such effort has led to a number of encouraging results According to the U.S Environmental Protection Agency’s 1994 annual assessment of urban air pollution,

Ngày tải lên: 11/08/2014, 13:22

... acute injury occurs following absorption of sufficient amounts of toxic gas or other forms of toxicants to cause destruction of tissues The destruction is often manifested by collapsed leaf margins ... role in the metabolism of environmental toxicants (xenobiotics) The metabolism of xenobiotics is often referred to as biotransformation The liver contains a rich supply of nonspecific enzymes, ... structure of the leaf.3,5 In animals and humans, inhalation of sufficient quantities of NO2 and sulfuric acid mists can damage surface layers of the respiratory system Trang 9Similarly, high levels of

Ngày tải lên: 11/08/2014, 13:22

... cells of the skin, the cells linin g the gastrointestinal tract or those of the alveoli in the lung. The passage of a compound across one of these membranes is therefore an 104 Environmental Toxicology ... physical, not chemical. The area of the filtering surface of glomeruli of a single kidney is as large as the surface of the entire body, and the glomerular capillaries of both kidneys would stretch ... and is mostly water. Out of some 200 l of filtrate a day, an average adult concentrates about 1.5 l of urine. It is obviously essential that most of the filtrate and many of its dissolved materials

Ngày tải lên: 11/08/2014, 13:22

... 34 132 Environmental Toxicology 17 Sheppard, D et al., Magnitude of the interaction between the bronchomotor effects of sulfur dioxide and those of dry (cold) air,... ratios of NADH/NADþ, ... inhibition of lipid biosynthesis, oxidation of unsaturated fatty acids in vivo, and stimulation of peroxidase activity. 8.3.4 H EALTH EFFECTS Studies on the pathological and physiological effects of NO ... produced thickening of the basement membranes, resulting in narrowing and fibrosis of the bronchioles. Emphysema-like alterations of the lungs developed, followed by death of the animals. 24 As

Ngày tải lên: 11/08/2014, 13:22

... 50 ng of Cd daily Tobacco smoke is one of the largest single sources of Cd exposure in humans Tobacco in all of its forms contains appreciable amounts of the metal Because the absorption of Cd ... oxidation of Hg gas, contamination of fish can occur even in remote areas 12.4.4 BIOTRANSFORMATION OFMERCURY Various forms of Hg are present in the environment Conversion of one form of Hg to another ... the environmental Pb levels are greatly increased Until recently, the primary source of environmental Pb in many countries was the combustion of leaded gasoline Lead has the low melting point of

Ngày tải lên: 11/08/2014, 13:22

... 2005byCRCPressLLC carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate). The mode of action of the carbamates is the same as that of organophosphates, i.e., inhibition of AChE. Aldicarb ... biomagnification of chlorinated hydrocarbons. These researchers studied the residues of organochlorine pesticide in adipose tissue samples of 25 persons (19 males and 6 females) from El Paso, Texas. None of ... level of 4.96 ppm, whereas the 230 Environmental Toxicology [16:52 26/8/04 P:/CRC PRESS/4365 MING-HO.751 (1670)/4365-013.3d] Ref: 4365 MING-HO YU Chap-013 Page: 230 227-254 Table 13.2 Summary of

Ngày tải lên: 11/08/2014, 13:22

... be 556,500 in 2003. 2 One of the most common characteristics of the development of a neoplasm in an organism is the long period of time between the initial application of a carcinogenic (cancer-causing) ... may be observed in this stage. The growth of altered cells is sensitive to environmental factors during the early phase of progression. 282 Environmental Toxicology [16:51 26/8/04 P:/CRC PRESS/4365 ... is the primary cause of the failure of treatment in cancer patients. The extent of the dissemination of the malignant cells is determined by the physiological condition of the host. During metastasis,

Ngày tải lên: 11/08/2014, 13:22