Shankar IAS Test: Environmental Pollution- 1 - UPSC MCQ

Correct Statement: 1
Yes, carbon monoxide (CO) can lower the amount of oxygen in your blood. When inhaled, CO binds to hemoglobin in red blood cells, forming carboxyhemoglobin (COHb). This reduces the amount of hemoglobin available to carry oxygen.

Ozone: It occurs naturally in the upper layers of the atmosphere.

This important gas shields the earth from the harmful ultraviolet rays of the sun. However, at the ground level, it is a pollutant with highly toxic effects. Vehicles and industries are the major sources of ground-level ozone emissions. Ozone makes our eyes itch, burn, and water. It lowers our resistance to cold and pneumonia.

• Photochemical smog (smog) is a term used to describe air pollution that is a result of the interaction of sunlight with certain chemicals in the atmosphere.

• One of the primary components of photochemical smog is ozone.

• Ground-level ozone is formed when vehicle emissions containing nitrogen oxides (primarily from vehicle exhaust) and volatile organic compounds (from paints, solvents, printing inks, petroleum products, vehicles, etc.) interact in the presence of sunlight.

1. Fly ash bricks are light in weight and offer high strength and durability.

   • This statement is correct. Fly ash bricks are known for being lightweight, having high strength, and offering durability. They are often used as a building material due to these properties.

2. Fly ash is a better fill material for road embankments and in concrete roads.

   • This statement is correct. Fly ash is used as a fill material in road embankments and in the construction of concrete roads. It improves the workability and strength of concrete, and it can also be used to stabilize soil in road construction.

3. Fly ash can be used in reclamation of wastelands.

   • This statement is correct. Fly ash can be utilized in the reclamation of wastelands by improving soil properties, enhancing fertility, and supporting vegetation growth, which helps in land restoration.

Given that all three statements are correct, the answer is: All of these.

Control of particulate matter: Two types of devices - arresters and scrubbers are used to remove particulate pollutants from the air. These are arresters and scrubbers.

Arresters: These are used to separate particulate matters from contaminated air.

Scrubbers: These are used to clean air for both clouds of dust and gases by passing it through a dry or wet packing material.

• Polluted water reduces Dissolved Oxygen (DO) content, thereby, eliminates sensitive organisms like plankton, molluscs and fish etc.

• Biocides, polychlorinated biphenyls (PCBs) and heavy metals directly eliminate sensitive aquatic organisms. Hot waters discharged from industries, when added to water bodies, lowers its DO content.

• DO, BOD, COD Presence of organic and inorganic wastes in water decreases the dissolved oxygen (DO) content of the water.

• Water having DO content below 8.0 mg L-1 may be considered as contaminated. Water having DO content below. 4.0 mg L-1 is considered to be highly polluted. DO content of water is important for the survival of aquatic organisms.

Effects of soil pollution on Agriculture; Reduced soil fertility; Reduced nitrogen fixation; Increased erosion; Loss of soil and nutrients; Reduced crop yield; Increased salinity; Deposition of silt in tanks and reservoirs

• Alpha particles can be blocked by a piece of paper and human skin.

• Beta particles can penetrate through the skin, while can be blocked by some pieces of glass and metal.

Gamma rays can penetrate easily to human skin and damage cells on its way through, reaching far, and can only be blocked by a very thick, strong, massive piece of concrete.