Source and influence of dioxin

Source and influence of dioxin
Dioxin (Dioxin) ,Also called two oxygen miscellaneous Qi, it is a colourless and tasteless lipid-soluble material with serious toxicity, dioxin actually dioxins (Dioxins) An abbreviation, what it referred to is not a single material, but structure and property are all very similar includes numerous similar things or different organic compound of two big classes which construct the body, the full name is two benzene and dioxin polychlorinateddibenzo-p-dioxin n (abbreviated as PCDDs) of many chlorine separately With two benzene and furan polychlorinateddibenzofuran (abbreviated as PCDFs) of much chlorine --Bound 2 benzene ring that chlorine atom replaces by 2 oxygen atoms; Combine furan (PCDFs) for two benzene of much chlorine Bound 2 benzene ring that chlorine atom replaces by an oxygen atom. Can replace 1- 4 chlorine atoms at each benzene ring, thus it is different to form the numerous one and construct the body, among them PCDDs is different to construct the body, PCDFs is different to construct the body. So, dioxin includes 210 kinds of compounds, this kind of material is very stable, the melting point is relatively high, it is extremely difficult to be soluble in water, can be soluble in the majority of organic solvent, it is a colourless and tasteless lipid-soluble material, so is very easy to accumulate in the organism. Microorganism and hydrolysis in the nature have a little effect on molecular structure of dioxin, so, it is very difficult for dioxin in the environment to degrade and dispel naturally. It includes 210 kinds of compounds. Toxicity of it very large, 130, 900 of Arsenicum of cyanide, have " century malicious " It claims. The international cancer research center has already classified it as human first class carcinogen. The environmental expert claims, " dioxin " ,Often exist in atmosphere, soil and water with the small particle, the main pollution sources is industries such as chemical metallurgical industry, rubbish burning, papermaking and producing the insecticide,etc.. The glue bag that daily life uses, PVC (polyvinyl chloride) Soft glue wait for thing contain chlorine, will release dioxin burn article these, suspend in the air. The toxicity of dioxin has a difference because the replacement position of the chlorine atom is different, so multiply the toxic coefficient of the equivalent (toxicequivalencyfactors by their content while appraising in the healthy dangerous degree of environment, TEFs) Receive the toxic quantity (toxicequivalent, TEQ) of the equivalent . Two evil Britain and Chinese Israel 2, 3, 7, 8-Combine four chlorine two benzene - right - dioxin ( 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin, 2, 3, 7, 8-TCDD) Toxicity the strongest,study too many most. Dioxin in the dioxin source atmospheric environment 90% come from city and industrial rubbish to burn. Leaded petrol, coal, antiseptic treatment timber and petroleum product, various offal especially biohazard waste produced dioxins while burning the temperature and is lower than 300-400 ��300-400 easily. Gather the vinyl plastics of chlorine, paper, chlorine, some production ink of pesticide, steel smelt and the intersection of catalyst and high-temperature the intersection of chlorine and the intersection of person who activate and course release dioxins in the environment. Dioxin exists in some pesticide products such as pentachlorophenol, 2 as the impurity even, 4,5 is - in T,etc.. The rubbish of urban industry burns the forming mechanism that the course hits dioxin still in research. Think that mainly there are three kinds of routes at present: 1. While to chloride and plastic burning such as ethylene of chlorine, it is lower than ��800 to burn the temperature, the chloride rubbish is not totally burnt, it is extremely apt to produce dioxins. Burning, forming benzene of chlorine, the latter becomes the synthetic forebody of dioxin; 2.Other chloride and including carbon material such as paper, woodwork, food residue,etc. and producing dioxins without benzene of chlorine through the catalysis of metal ion such as copper, cobalt. 3.Make the chemical material including pesticide, especially the chemical material of chlorine department, like insecticide, weed killer, timber preservative, deciduous pharmaceutical (American army is used in the Vietnam War) , many chlorine is united and derived in the course of products such as benzene,etc.. Dioxin in the atmosphere is generally very low in density. Compared with countryside, contain dioxin of higher density in the city, industrial area or atmosphere from closer area of the pollution sources. Dioxin amount that the general crowd passes breath with exposed route is few, namely estimate for about 1% by intaking amount of digestive tract, about 0.03pgTEQ (kg d) . In cases some is special, through breathe the intersection of route and exposed dioxin quantity, can't be ignored either. The investigation reveals, it is 806pgTEQ/L that the rubbish burns dioxin content in employee's blood, crowd's level that it is normal is about 40 times. Dioxin discharged into the atmospheric environment can be adsorbed onto particulate matter, subside water body and soil, then enter the human body by rich collection of the food chain. The food is a main source of dioxin in the human body. And nursing can cause dioxin of foetus and infant and pre-school children to expose by the placenta. The intersection of people and getting easy cancer that contact often. The health influences dioxins to be the representatives of environmental endocrine interference things. They can interfere with the endocrine of the organism, produce extensive health influence. Dioxin can cause the female animal's ovarian function obstacle, inhibit the function of estrogen, make female animal to be infertile reducing, miscarrying etc. by the intersection of child and son. Dioxin of the low dosage can make the fetus mouse produce palatoschisis and renal pelvis water accumulation. Will present the male animal of dioxinning, the meticulous afterbirth is reduced, the ripe sperm degradates, the male animal is feminized etc.. Study to find, keep in touch in production in epidemiology 2, 3, 7, 8-Serum testis ketone level of the male worker of TCDD reduces, urges bubble hormone of ovum and luteinic hormone to increase, brief on it to resist androgen (antiandrogen) With the function of making men feminize. Dioxin has obvious immune toxicity, can cause animal's thymus to wither, cell immunity and humoral immunological function to reduce etc.. Dioxin still can cause the intersection of skin and damage, can observe the intersection of skin and the intersection of transition and the intersection of corner and take, pigmentation and the intersection of chlorine and emergence of analeptic,etc. in exposed experimental animal and crowd. Dioxin contaminate animal can present the intersection of liver and swelling, the intersection of essence and the intersection of cell and hyperplasia with changing the sex and necrosis happen when being loose, serious. 2,3,7,8 - TCDD has carcinogenic the extremely strong one on animal. Use 2, 3, 7, 8-TCDD contaminates, tumour that can bring out a plurality of positions in the experimental animal. Epidemiology research indicate dioxin expose, can increase crowd, suffer from danger degree of cancer. The result studied according to animal's experiment and epidemiology, international cancer research institution (IARC) in 1997 Will 2, 3, 7, 8-TCDD confirms for a kind of human carcinogen.

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