Tag: air pollution and its effects

The heat island is a phenomenon where heat can no longer escape. The high temperature in urban areas as compared to rural areas can be called heat island effect. With the loss of vegetation and land surface in urban areas, heat gets trapped between buildings and dense areas which cause a warming effect. The air pollution due to greenhouse gases is responsible for this. Bigger cities have large heat island effects, the waste heat from energy use, seasonal changes, local weather also contribute to heat islands.

• Classical smog, also known as London smog or Sulphurous smog, is formed when there is high concentration of sulphur dioxide and particulate matter produced due to combustion of fuels. It occurs in cold and humid climate and has reducing nature.
• Photochemical smog, also known as Los Angeles smog, is formed when sunlight acts on the oxides of nitrogen and hydrocarbons produced from factories or by automobiles. It occurs in warm and dry climate and has oxidising nature.

• Classical smog, also known as London smog or Sulphurous smog, is formed when there is high concentration of sulphur dioxide and particulate matter produced due to combustion of fuels. It occurs in cold and humid climate and has reducing nature.
• Photochemical smog, also known as Los Angeles smog, is formed when sunlight acts on the oxides of nitrogen and hydrocarbons produced from factories or by automobiles. It occurs in warm and dry climate and has oxidising nature.

• Motor vehicle emissions are one of the causes of poor air quality. Other causes include wood-burning fires, fires on agricultural land, exhaust from diesel generators, dust from construction sites, burning garbage and illegal industrial activities in Delhi.
• Air pollution exposure can trigger new cases of asthma, exacerbate (worsen) a previously-existing respiratory illness, and provoke development or progression of chronic illnesses including lung cancer, chronic obstructive pulmonary disease, and emphysema. If untreated result in death.
  
• An annual number of deaths in Delhi believed to be due to air pollution is 7500.
  
• So, the correct answer is '7500'.

There are a number of chemicals, which causes lung cancer and one of them is 3, 4- benzopyrene. Benzopyrene mutates three key positions in the p53 gene, which leads to lung cancer. Hence, the correct answer is option C.

Acid rain is a mixture of wet and dry deposition (deposited material) from the atmosphere containing higher than normal amounts of nitric and sulfuric acids. Sulfur dioxide ($SO _2$) and nitrogen oxides (NOx) are the principal pollutants, that cause acid precipitation. $SO _2$ and NOx emissions released to the air react with water vapor and other chemicals to form acids that fall back to earth. The majority of NOx comes from cars, buses, trucks, and other forms of transportation and from power plants. Therefore, the correct answer is option E.

Skeletal fluorosis or osteoporosis is a bone disease caused by excessive accumulation of fluoride in the bones. In advanced cases, skeletal fluorosis causes pain and damage to bones and joints. Due to a high fluorine concentration in the body, the bone is hardened and thus less elastic, resulting in an increased frequency of fractures. Other symptoms include thickening of the bone structure and accumulation of bone tissue, which both contribute to impaired joint mobility. Ligaments and cartilage can become ossified. As a result, bone flexibility decreases making the bone more amenable to fractures.