環(huán)境污染及對(duì)健康的危害

1、 Preventive medicine 第二節(jié) 環(huán)境有害因素對(duì)健康的危害四、環(huán)境污染及對(duì)健康的危害 Qingqing NongDepartment of Environmental Medicine 中國(guó)經(jīng)濟(jì)發(fā)展伴隨嚴(yán)重環(huán)境污染問(wèn)題日益增多的生活拉圾工業(yè)污染導(dǎo)致水養(yǎng)魚(yú)類(lèi)的大量死亡煙頭小也是污染源酸雨腐蝕的森林受藍(lán)藻污染的太湖水淮河上游被化工廠(chǎng)排出物污染恕吼我們還能生存多長(zhǎng)時(shí)間？據(jù)中國(guó)新華社報(bào)導(dǎo)：引言 由于人為或自然的原因，使環(huán)境中污染物的量超出了環(huán)境的自?xún)裟芰?，造成環(huán)境質(zhì)量下降或惡化，直接或間接地影響健康，稱(chēng)為環(huán)境污染 環(huán)境污染 environment pollution 由嚴(yán)重的環(huán)境污染引

2、起的地區(qū)性疾病稱(chēng)公害病。必須得到法律、醫(yī)學(xué)和有關(guān)政府部門(mén)認(rèn)可，方可確定為公害病。如水俁病等。 公害病public nuisance disease 1.直接危害 （1）急性中毒 當(dāng)大氣污染物的濃度在短期內(nèi)急劇增高，使周?chē)巳何氪罅课廴疚锟稍斐杉毙灾卸尽?重慶開(kāi)縣天然氣井噴事件 (一)大氣污染對(duì)健康的危害 主要由煙霧事件和生產(chǎn)事故引起煙霧事件煤煙型煙霧（coal smog）事件光化學(xué)煙霧（ photochemical smog）事件 There are two types of ambient air pollution as defined by their different source

3、s :coal smog and photochemical smogIn the great Smog Disaster in London in 1952, four thousand people died in a few days due to the high concentrations of pollution.A dense smog caused by heavy coal combustion during the winter of 1952.煤煙型煙霧事件按煙霧形成原因分類(lèi) 形成 主要污染物 舉例煤煙型煙霧事件 煤煙和工業(yè)廢氣 煙塵、 馬斯河谷煙霧事件 大量排入大氣，

4、 硫酸霧 多諾拉煙霧事件 不能充分?jǐn)U散所致 SO2 倫敦?zé)熿F事件光化學(xué)型煙霧事件按煙霧形成原因分類(lèi) 形成 主要污染物 舉例光化學(xué)型煙霧事件 汽車(chē)尾氣中的氮氧 臭氧、醛類(lèi)、 美國(guó)洛杉磯 化物和揮發(fā)性有機(jī)物 過(guò)氧?；跛狨?光化學(xué)煙霧事件 在日光紫外線(xiàn)照射 下經(jīng)光化學(xué)反應(yīng)形成Photochemical smog is the chemical reaction of sunlight, nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the atmosphere and forms a mix of inimicial

5、chemicals including ozone, and PAN (peroxyacytyl nitrate)，acrolein that can be very dangerous. Automobile exhaust is the major source of photochemical smog in most urban areas.One of the most important of these is ozone (O3) . It is a strong oxidant and can destroy lung tissue and chlorophyll in pla

6、nts. Other photochemical oxidants include peroxyacetal nitrate (PAN) and acrolein, both of which are strong oxidants and can damage materials. PAN is also a severe eye irritant. Smog Disaster of Los Angeles 光化學(xué)煙霧事件What is the difference between coal smog and photochemical smog ？ 煤煙型煙霧事件光化學(xué)型煙霧事件污染來(lái)源煤

7、和石油制品燃燒石油制品燃燒主要污染物顆粒物、SO2、硫酸霧HCS、NOX、O3、SO2、CO、PANS發(fā)生季節(jié)冬季夏秋季發(fā)生時(shí)間早晨中午或午后氣象條件氣溫低（-14）、氣壓高、風(fēng)速很低、濕度85%以上、有霧氣溫高（2433）、風(fēng)速很低、濕度70%以下、天氣晴朗、紫外線(xiàn)強(qiáng)烈地理?xiàng)l件河谷或盆地易發(fā)生南北緯度60以下地區(qū)易發(fā)生癥狀咳嗽、喉痛、胸痛、呼吸困難，伴有惡心，嘔吐、發(fā)紺等，死亡原因多為支氣管炎、肺炎和心臟病眼睛紅腫流淚、咽喉痛、咳嗽、喘息、呼吸困難、頭痛、胸痛、疲勞感和皮膚潮紅等，嚴(yán)重者可出現(xiàn)心肺功能障礙或衰竭易感人群老年人、嬰幼兒以及心、肺疾病患者心、肺疾病患者煤煙型煙霧事件與光化學(xué)型煙霧

8、事件的比較生產(chǎn)事故和意外事故引發(fā)的急性中毒事件 印度博帕爾毒氣泄漏事件咽炎、氣管炎、 Chronic Obstructive Pulmonary Diseases （2）慢性危害 環(huán)境中有害物質(zhì)以低濃度、長(zhǎng)時(shí)間反復(fù)作用于機(jī)體所產(chǎn)生的危害。 1. 慢性炎癥 2.變態(tài)反應(yīng) 3.非特異性疾病多發(fā) 4.致癌作用如甲醛、SO2、某些洗滌劑如苯并芘、石棉、砷、鎳、鉻唾液溶菌酶含量下降 SIgA減少 The diseases and symptoms of illnesses associated with specific air pollutants range from eye and throat

9、irritations, respiratory infections, and bronchial asthma to cardiovascular disease, lung cancer, and genetic mutations.2.間接危害 (1）溫室效應(yīng) (2）形成酸雨 （3）破壞平流層的臭氧層 Air pollution can also create acid rain, depletion of the ozone layer and global warming which are major global environmental concerns. Climate

10、change The worlds climate is controlled by many factors. One of the major factors is Earths temperature. During the late 1970s and into the 1980s, scientists became concerned that increases in atmospheric carbon dioxide levels could cause Earths temperature to increase, which could lead to vast chan

11、ges in weather patterns. Greenhouse effectsGreenhouse effectsCarbon dioxide traps some of the infrared radiation that escapes from the Earth, making the Earth warmer, much as the glass does in a greenhouse. The process has been termed the greenhouse effect.Methane, chlorofluorocarbons (CFCs), and ni

12、trous oxide (N2O) are also greenhouse gases.infrared radiation make the Earth warmer2.陸地和海洋生態(tài)系統(tǒng)受到影響，植物群落及浮游生物發(fā)生改變3.氣溫增高有利于病原體繁殖，使某些傳染病、寄生蟲(chóng)病及食物中毒發(fā)病率1.使兩極冰川融化，海平面上升，陸地面積減少。溫室效應(yīng)的影響1. It give rise to water- and food-borne diseases; vector-borne and rodent-borne diseases; or food and water shortages. 2.T

13、emperature-related illness and death could increase.3. It increases human exposure to spores and moulds. Consequently, allergic diseases could increase.4. This could result in melting of the ice caps, rising sea levels, coastal flooding, shifting of crop-producing regions, and adverse impacts on pop

14、ulations of humans and other life. Negative impacts of Greenhouse effectsAcid rainAcid rain is rain or any other form of precipitation with a pH of less than 5.6. When a pollutant, such as sulfuric acid combines with droplets of water in the air, the water (or snow) can become acidified . 危害1 酸霧刺激呼吸

15、道并發(fā)生慢性炎癥，對(duì)嬰幼兒影響更大 酸雨acid rain 危害2 水體酸化使水生生物生長(zhǎng)受到影響，魚(yú)群減少，水生植物受影響，影響水體自?xún)?酸雨acid rainEffects of acid rain on aquatic systems are more established. Thousands of lakes can no longer support the growth of fish, and other aquatic life (frogs, plants, etc.) is also affected.The lowered pH can also change the

16、 speciation of toxic metals in the water and sediment, making them more available to the organisms. 危害3 酸雨能腐蝕建筑物，破壞輸水管網(wǎng)，使水質(zhì)惡化。 酸雨acid rainThe acids are very corrosive and can attack many materials.Forests around the world are dying at an alarming rate, due in part to acid rain. Some areas have seen

17、50 percent or greater mortality of trees, and even higher decreases in survival of new saplings. 酸雨腐蝕雕刻酸雨腐蝕的森林酸 雨Stratospheric ozone depletionOzone is mainly broken down by chemicals called ChloroFluoroCarbons （CFCs ）and also by nitrogen oxides. skin cancercataractsozone depletion The release of chlorofluorocarbons and other atmosphe