Air & Water Pollution — Set 6

Correct Answer: B. Fluoride

Fluorosis is caused by long-term ingestion of high levels of fluoride, often through naturally contaminated groundwater. It leads to the staining of teeth and, in severe cases, the crippling of the skeletal system. Many parts of India face this problem due to specific geological formations.

Correct Answer: B. To remove gases and particles using a liquid spray

Wet scrubbers use a liquid (usually water) to collect dust or absorb gaseous pollutants like sulfur dioxide from exhaust streams. The pollutants are transferred from the air to the liquid, which is then treated separately. It is a versatile technology for controlling a wide range of industrial emissions.

Correct Answer: B. Burning of biomass fuels for cooking

Traditional stoves using wood, dung, or coal release high levels of smoke and particulate matter inside homes. This leads to millions of premature deaths every year due to chronic lung diseases and strokes. Promoting clean cooking energy like LPG is a major developmental goal.

Correct Answer: A. Methylmercury

Methylmercury was released by a chemical factory into Minamata Bay, where it was absorbed by fish and shellfish. Local people who ate the seafood suffered from severe brain and nervous system damage. This disaster highlighted the dangers of industrial heavy metal waste in aquatic environments.

Correct Answer: B. Absorption of excess Carbon dioxide from the air

The oceans absorb about 30% of the CO2 released into the atmosphere, which reacts with water to form carbonic acid. This change in chemistry harms marine life that relies on calcium carbonate to build shells. It is often referred to as the 'other CO2 problem' besides global warming.

Correct Answer: A. The Lungs

Silicosis is a lung disease caused by breathing in tiny bits of silica, a mineral found in sand and rock. It leads to permanent scarring and hardening of the lung tissue, making it difficult to breathe. It is a common occupational disease among stone-crushers and glass-factory workers.

Correct Answer: B. Biochemical Oxygen Demand

BOD indicates the amount of organic pollution in a sample of water. Higher BOD means more oxygen is needed by bacteria to break down the waste, leaving less for fish. It is one of the most important measures used in environmental monitoring and wastewater management.

Correct Answer: B. Vehicle exhaust and Sunlight

Smog is a type of intense air pollution that reduces visibility and irritates the eyes and lungs. It forms when industrial and vehicle emissions react chemically with sunlight in the lower atmosphere. Stagnant air and high temperatures often worsen the smog condition.

Correct Answer: B. Arsenic

Arsenicosis is the chronic health condition resulting from drinking water with high arsenic levels over a long period. It typically manifests as skin color changes, hard patches on palms, and eventually various cancers. It is a major issue in the Ganga-Brahmaputra river basins.

Correct Answer: A. Reducing Greenhouse gas emissions

The Kyoto Protocol is an international treaty that committed industrialized nations to reduce their greenhouse gas emissions. It was adopted in 1997 and provided the framework for later climate agreements like the Paris Accord. It recognized that human-made emissions are the main cause of the global temperature rise.