Air pollution and its effects on Human passagesIn the search for health effects of air pollution there is a tendency to study primarily the effects of pollution on the lungs and air passages. There are, however, also more generalized effects of air pollution. A number of pollutants that are inhaled via the air are absorbed into the circulation, and can affect various parts of the body (e.g. heavy metals, carcinogens, etc.). Furthermore, pollutants in the air are deposited on land or in water, and thus may enter the body via the digestive system or skin. Not all persons react to inhaled irritants in the same way. Clinical investigations have shown that two different types of sensitivity can be distinguished: so-called specific sensitivity and a specific irritantaltivity give rise to an allergic reaction in the body by stimulating formation of specific antibodies. Depending on the place in the body where these antibodies settle e.c. in the blood vessels or attached, to cells), different types of allergic reaction occur. In the lungs and air passages the allergic reactions produce symptoms of hayfever, asthma, granulomatous reactions, etc. In the people with a specific sensitivity obstruction of the air passages may appear when irritants are inhaled in small amounts that cause no measurable reaction in normal people. This sensitivity is called aspecific because no single agent causes the reaction. People with an aspecific sensitivyty (also called hyperactivity) of the air passages may react to fog, tobacco, smoke, perfumes, paint, sometimes even to cold. air. Epidemiological investigations have shown that now there is a real cause-and-effect relationship between air pollution and lung diseases. Упражнение 1. Прочтите и переведите заголовок текста. Просмотрите текст. О чем идет речь? Упражнение 2. Прочтите и переведите интернациональные слова: tendency stimulate heavy metal reaction carcirogen symptom clinical asthma specific granulomatous aspecific hyperactivity allergic epidemiological Упражнение 3. Запомните произнесение и перевод следующих слов: search исследование, поиск passage путь (дыхательный) inhale вдыхать via через absorb всасывать, впитывать, абсорбировать deposit откладывать, давать осадок irritant раздражитель sensitivity чувствительность depending on в зависимости от hayfever сенная лихорадка obstruction затруднение, препятствие single определенный fog густой туман perfume аромат, запах, духи paint краска 4. relationship взаимоотношение, отношение, связь Упражнение 4. а) Прочтите текст, используя новую лексику. б) Найдите и переведите абзац, в котором говорится о: specific and aspecific sensitivity Упражнение 5. Расскажите о путях проникновения вредных веществ в организм человека. Используйте данную информацию: Pollutants inhaled via the air heavy metal are absorbed into the circulation carcinogens deposited into the body on land and in water via the digestive system via the skin
|
