预防医学教学课件：Benzene Poisoning

1、Benzene Poisoning1. Physical and chemical properties Colorless, volatile liquid Characteristic odor (aromatic) Boiling point:80.1 Gravity: 2.77 Soluble less in water, easily in fat and organic solvents2. Opportunities of exposure Distillation of coal tar or cracking of crude oil Raw material in the

2、production of many aromatic compounds Solvents for rubber, plastics, paints, and glues etc3Benzene Poisoning2002年1月，浙江省温岭市制鞋企业发生苯中毒事件，中毒28人，4人死亡。2002年3月，北京市某包装制品企业发生苯中毒事件，13人中毒，2人死亡。2002年3月，广州市白云区某鞋厂17名工人受苯影响，导致不同程度的血液 异常，4人严重中毒。2002年3月，河北省高碑店市白沟镇生产箱包的企业发生严重的苯中毒事件， 共发现25名苯中毒人员，其中6人死亡，最小16岁，最大19岁。200

3、2年5月，山东时风集团重大苯中毒案，造成31名工人中毒，其中2人死亡。2002年10月，广东省东莞市某塑胶公司，发生苯中毒事件，8人中毒。2002年重大苯中毒事件2010年3月，河南许昌。 30名员工被诊断为慢性重度苯中毒， 主要表现为全血细胞减少或再生障碍性贫血。现况依然堪忧 3. ToxicologyAbsorption & distributionbenzeneInhalationSkin (little)Vapour50%Blood bone marrowbrainnerve system Biotransformation & excretion40%brenzcatechinben

4、zenediolphenolsulfuric acid glucuronic acidUrinebenzene epoxidemuconic acidCO2 +H2OBenzeneCytochrome P450Kidneylung Mechanism of intoxication Phenol: inhibit karyokinetic division Bone marrow injuries: cytokine hemopoietic stem cell DNA damage：DNA adduct Oncogene activation: ras, c-fos, c-myc 4. Cli

5、nical manifestation Acute poisoning Irritation of mucous membrane Narcotic effects of central nerve system Chronic poisoning* Nerve system: neurasthenic syndrome Hematopoietic system: Leukopenia (白血球减少症)Thrombocytopenia (血小板减少症) Aplastic anemia (再生障碍性贫血)Pancytopenia (全血细胞减少症) Panmyelopathy (全骨髓病)Leu

6、kemia others: skin, reproduction, immunology Aplastic anemiaGranulocytic leukemia Diagnosis Observation subject Acute poisoning Chronic poisoning Treatment Removed and avoid further exposure Recover the hematogenic ability Allopathy7. Prevention and Control Less harmful substitutes Technical procedu

7、re innovation Ventilation Personal protectionAromatic amino and nitro compoundsH-NH2-NO2HhalogenHalkane anilinenitrobenzene 1. Physical and chemical properties High boiling point Low volatility Dissoluble in water, soluble in lipid Aniline（C6H5-NH2） Nitrobenzene（C6H5-NO2）2005年11月14日10时，吉化公司松花江入江口水样有

8、强烈的苦杏仁气味，苯、苯胺、硝基苯、二甲苯等主要污染物指标均超过国家规定标准。随着水体流动，污染带向下转移。11月20日16时到达黑龙江和吉林交界，硝基苯超标，最大超标倍数为29.1倍，污染带长约80公里，持续时间约40小时。 2. Opportunities of exposure中石油吉林石化公司苯胺车间爆炸事故，导致80公里长的高度污染水团顺松花江而下，威胁黑、吉两省数百万民众，甚至波及中俄关系。 危机过后，国家投资百亿元用于松花江污染的治理 3. Toxicology Absorption & excretionAromatic amino and nitro compoundsski

9、ninhalationurinebiotransformation3. ToxicologyMechanism of intoxication*hematopoietic system: 1)MethemoglobinemiaMeHbFe2+Fe3+Bearing oxygen ability loseAffinity of Fe2+and oxygenHbdirect oxidationindirect oxidationAnilinenitrobenzeneNitrite etc.(ferroheme)(globin)spatial configuration of hemoglobin3

10、) Hemolysis and Heinz bodyAromatic amino and nitro compoundsGSH exhaustHemolysisReact with -SH on globinHeinz bodymononuclear macrophage2) Sulfohemoglobin4) AnemiaHeinz body (2) Liver and Urinary damage Direct damage: Decomposed products deposit in liver, kidneyHemolysis Toxic hepatitis Secondary da

11、mage:Proximal convoluted tubule epithelial cells degeneration and necrosis(4) Skin lesion and allergizationContact dermatitisSensitization dermatitisBronchial asthma(5) Lens damage: toxic cataract(6) Oncogenesis: bladder carcinoma(3) nervous system 4. Treatment Removed and avoid further exposure met

12、hylene blue (Methemoglobinemia) AllopathyNADPHNADP+Methylene bluein blueMeHbHbTreatment of acute poisoningMethylene bluein whiteTreatment of methomeglobin formation: Methylene blue (1-2 mg/body weight (Kg)5. Prevention and Control Technical procedure innovation Periodic examination Ventilation Perso

13、nal protectionAniline1. Physical and chemical properties Molecular weight:93.1 soluble in organic solventAniline2. Opportunities of ExposurePrinting and dyeing industryDyestuffpharmaceutical industry3.ToxicologyanilineInhalationSkinurineVapourphenylhydroxylamine 4. Clinical manifestationAcute poison

14、ingChronic poisoning 5. Diagnosis Contact reaction Mild poisoning Moderate poisoning Severe poisoning Trinitrotoluene (TNT)1. Physical and chemical properties Primrose crystal Molecular weight:227.13 Melting point:82 Boiling point:240 Gravity:1.65 Dissoluble in water, soluble in organic solvent2. Op

15、portunities of ExposureUse as detonator in National defenceMiningDigging tunnelArchitectureDust 3.ToxicologyTNTInhalationSkinurineVapourGlycuronicacid Biomarker: TNT, 4-amino-2,6-binitrotoluene (4-A)urineTNTLiverP450e GSH exhaust lipid peroxidation covalent bonding with biomacromolecule NADPH NADP+Free radicalLens damage: toxic cataractLiver damageHaematopoietic systemNerve system3.Toxicology4. Clinical manifestation Acute poisoning Chronic poisoning(1) liver: Toxic hepatitis (2) lens: Toxic cataract(3) Haematopoietic system: anemia (4) Reproductive system:(5) skin: dermatitidis (6) other