据俄罗斯《真理报》报道，每一个人都清楚，大都市里的空气受到了污染，但科学家认为，非都市区的空气质量不一定更好，哪怕是简单的呼吸，都有潜在的危险。最近臭氧又进入这个黑名单。现在，当你在暴风雨过后准备呼吸新鲜空气，请三思而后行。下面是主要的空气污染物：
悬浮颗粒物
悬浮颗粒物是直径不超过10微米的尘埃、煤烟和烟尘颗
粒。任何类型的燃料燃烧和土壤自然排水，都会形成悬浮颗粒物。在大城市，这些粒子是雾霭形成的主要原因。根据附着在粒子表面的化学物成分，这些悬浮颗粒物
既有可能是无害的，也有可能是非常危险的。呼吸道受到尘埃和煤烟的危害最大，这种情况也有可能会引发其他疾病，例如心脏病和肿瘤。当空气里含有大量氮和氧
化硫时，悬浮颗粒物尤其危险。
二氧化硫
二氧化硫与空气里的水结合，会形成亚硫酸。有大量二氧化硫被排放到空气里的地区，会经常下酸雨，这种雨水呈酸性，对植物和土壤微生物有害。二氧化硫对人也有危害，尤其是那些患有肺病和支气管疾病的人。
最近几年，欧洲、美国和俄罗斯的二氧化硫水平已经有所下
降，而且目前在继续下降。观察发现，拥有发电站、锅炉房和冶炼厂的地方，空气里的二氧化物水平更高，这些设施都燃烧煤。记录显示，西伯利亚西北的诺里尔斯
克市的二氧化硫水平最高，该地空气里的二氧化硫浓度超过容许限度值近三倍。
氮氧化物
汽车发动机、发电站和工厂进行的高温燃烧会产生氮氧化
物。它跟二氧化硫一样，也能引起酸雨。除此以外，这种化学物质可跟阳光发生化学反应。因此，它是通过浓烟释放出来的更加危险的毒素。被氮氧化物污染的空气
会变成棕褐色。即使浓度很低的氮氧化物也会干扰呼吸，引起咳嗽。在氮氧化物浓度很高的地区出生的儿童，经常会患严重的呼吸道疾病。
一氧化碳
这是人们最熟悉的化合物。它主要由汽车燃料不完全燃烧产生，可在空中逗留近一个月，然后经氧化形成危害相对较小的二氧化碳。一氧化碳可在很长时间里降低血液输送氧气的能力，这种情况会导致大脑和心脏缺氧，致人死亡。
臭氧
我们都知道，在距离地球大约9英里到30英里
(14.48公里到48.28公里)的地方，臭氧形成地球的保护层，避免人类家园遭受太阳破坏。然而臭氧位于相对较低的地方时，就会丧失其保护功能。这时
它不但起不到保护作用，还是一种非常强效的氧化剂，对植物和动物都很危险。在臭氧影响下，人的呼吸道粘膜会被灼伤。在炎热的城市度过夏季的儿童，更易遭受
臭氧侵扰。
城市里的臭氧浓度最高。尾气里包含大量轻组有机物和氮氧化物，这些物质常在热天和阳光充足的日子形成，是构成臭氧的基本成分。随后臭氧与空气结合，并借助风到达很远的地方。
铅通过空气、食品和水进入人体。它还能依附在尘粒上，储存在血液、骨骼和软组织里。铅可引起严重的肾病、肝病、神经系统疾病和其他器官问题。除此以外，它还能导致心理紊乱，痉挛和智力迟钝，尤其对儿童危害更大。
几十年来，铅一直通过含铅汽油产生的尾气进入大气。2003年，俄罗斯禁止生产含铅汽油，这导致该国大气里的铅浓度迅速降低。铅跟其他重金属一样，也能渗透到植物里，因此人们在燃烧落叶时，一定要小心，因为这种非常危险的毒素可能会通过燃烧，再次回到空气里。
挥发性有机物
这种化学物包括苯、甲醛和1,3-丁二烯
(Butadiene)，它们是由汽车燃料不完全燃烧和石油、油及润滑剂蒸发形成。即使浓度很小，也能引发癌症、心血管疾病和肝脏及肾功能障碍。它们可能
还会引起先天畸形和不孕不育。挥发性有机物很容易与氧气和其他氧化剂发生化学反应，释放出更加危险的毒素。
有毒物质
即使空气中含有微量有毒物质，也会对植物和动物产生严重
危害。美国《洁净空气法》列举了188种由工业设备释放、21种由汽车尾气释放出来的这种物质，以及33种城市空气里包含的典型有毒化合物。其中大部分毒
素可致癌或导致DNA受损。它们附着在悬浮颗粒物表面后，对人畜产生的危害更大。最近发现，由有毒物质引起的变异，甚至可以遗传给后代。较小浓度的有毒物
质只有在特殊环境下才能显现出毒性。毒素浓度是评估生态环境的一个重要标准。
Breathing Fresh Air Can Be Extremely Dangerous
Everyone knows that the air in
metropolises is contaminated. Yet, scientists believe that the quality
of air in Siberia or in the Far East of Russia is no better than, say,
in Moscow. Simple breathing can be dangerous. Recently, ozone made it
to the black list. Now, think twice before you breathe in that fresh
smell after a thunderstorm.
Here is the list of the major air contaminators:
Suspended Particles
These are particles smaller than 10 microns - dust, soot and smoke.
Suspended matters form. during
combustion of nearly any type of fuel as well as during soil drainage.
In the cities, these particles are the main reason for smog.
Suspended matters may be both nearly
harmless and extremely hazardous, depending on chemical compounds
settling on the particles’ surface. Respiratory passages suffer from
dust and soot the most, while development of other diseases is also
possible, including heart diseases and cancerous tumors. Suspended
particles are especially dangerous when the air contains excessive
amounts of nitrogen and sulfur oxides.
Sulphur Dioxide (SO2)
This is a gas that, when combined
with water in the air, forms sulfurous acid. As a result, the areas
where a great deal of SO2 is emitted into the air have frequent acid
rains harmful for plants and soil microorganisms. Sulphur dioxide is
hazardous for people as well, especially those suffering from lung and
bronchus diseases.
Within the recent years the levels of
dioxide in Europe, the USA and Russia have dropped significantly and
continue dropping. Higher levels of dioxide are observed in the areas
where power stations, boiler rooms and smelters use coal as a fuel. The
largest amounts of SO2 are registered in Norilsk, where average
concentration exceeds the admissible limit value nearly three-fold.
Nitrogen Oxide (NOx)
This chemical is released during
combustion at high temperatures, for example, in car engines, at power
station and factories. Same as sulphur dioxide, nitrogen oxide causes
acid rains.
Besides, this chemical participates
in chemical reactions involving the sun light. As a result, even more
dangerous toxins are released along with heavy smog. The air
contaminated with nitrogen oxide turns brownish-black.
Even low concentration of nitrogen
oxide causes interrupted breathing and cough. Children raised in the
areas with high concentration of NOx frequently suffer from serious
respiratory tract diseases.
Carbon Oxide (CO)
This is the most familiar compound.
It is a product of incomplete fuel combustion mostly released by cars.
It lingers in the air for approximately a month, and then oxidized to
form. a relatively harmless CO2. Carbon oxide decreases the ability of
blood to transfer oxygen for a long time. As a result, the heart and
brain suffer from oxygen deficit.
Ozone (O3)
We all know that ozone forms a
protective layer nine to 30 miles above the Earth’s surface, keeping
the planet from the dangerous Sun. Yet, ozone located relatively low
lacks this protective function. On the contrary, it is a strong
oxidizer, dangerous for plants and animals. Affected by ozone, humans
suffer from serious burns of the respiratory tract mucosa coat.
Children who spend the summer in cities with hot climate suffer from
ozone the most.
The largest concentrations of ozone
are observed in the cities. Exhaust contains high quantities of light
organic matters and nitrogen oxide, the building blocks of ozone that
forms during hot weather and sunny days. Later, ozone mixes with the
air and travels long distances with the wind.
Lead (Pb)
Lead gets into the human body with
air, food and water. It also settles on dust particles and is stored in
blood, bones and soft tissues. Lead causes serious kidney, liver,
nervous system and other organs diseases. It also causes psychological
disorders, fits and mental retardation, especially in children.
For many decades, lead was thrown
into the atmosphere along with exhausts of leaded gasoline. In Russia,
production of leaded gasoline was banned in 2003, which caused a
significant decrease in concentration of lead in the atmosphere.
Like other heave metals, lead
penetrates plants, so people should be careful when burning fallen
leaves, because the dangerous toxin will get back into the air.
Volatile Organic Matters
These compounds, that include benzene, formaldehyde, and 1,3
- butadiene, form. during incomplete combustion of car fuel or
evaporation of petroleum, oil and lubricants. Even relatively small
concentrations may cause cancer, cardiovascular diseases and liver and
kidney malfunction. They may also cause congenital deformities and
infertility.
Volatile organic matters easily enter
into chemical reactions with oxygen and other oxidizers, releasing even
more dangerous toxins.
Toxic Matters
They include compounds that cause
serious harm to plants and animals even in trace amounts. The American
Clean Air Act lists 188 of such matters released by industrial
facilities, 21 matters in car exhaust and 33 compounds typical for the
city air.
Most toxins are cancerogenic and
cause DNA damage. They are particularly harmful when settled on the
surface of suspended particles.
It was recently discovered that
mutations caused by toxins can even be inherited. Considering small
concentration, it is impossible to reveal toxins without special
equipment. Yet, toxins concentration is one of the main criteria for
assessing ecological environment.
