Waste, contamination and remediation — UPSC Prelims PYQs

Which of the following is/are the most significant implication(s) of obtaining Oeko-Tex certification for Eri Silk in the global textile industry? 1. It allows Indian exporters to compete in high-end markets that prioritise chemical-free products. 2. It confirms that Eri Silk meets international safety, environmental, and quality standards, enabling its entry into premium eco-conscious markets. Select the answer using the code given below:

At the United Nations Ocean Conference (UNOC) held in June, 2025 in France, the Food and Agricultural Organization (FAO) of the United Nations demonstrated its leading voice on marine and ocean issues, especially on sustainable fisheries and aquaculture for resilient livelihood and "Blue Transformation". Which of the following combinations about the "Four Betters" proposed by FAO for "Blue Transformation" is correct?

Consider the following: I. Cigarette butts II. Eyeglass lenses III. Car tyres How many of them contain plastic?

Consider the following statements: Statement I: Circular economy reduces the emissions of greenhouse gases. Statement II: Circular economy reduces the use of raw materials as inputs. Statement III: Circular economy reduces wastage in the production process. Which one of the following is correct in respect of the above statements?

With reference to perfluoroalkyl and polyfluoroalkyl substances (PFAS) that are used in making many consumer products, consider the following statements: 1. PFAS are found to be widespread in drinking water, food and food packaging materials. 2. PFAS are not easily degraded in the environment. 3. Persistent exposure to PFAS can lead to bioaccumulation in animal bodies. Which of the statements given above are correct?

Consider the following statements: Statement-I: Many chewing gums found in the market are considered a source of environmental pollution. Statement-II: Many chewing gums contain plastic as gum base. Which one of the following is correct in respect of the above statements?

"Membrane Bioreactors" are often discussed in the context of:

Consider the following statements regarding World Toilet Organization : 1. It is one of the agencies of the United Nations. 2. World Toilet Summit, World Toilet Day and World Toilet College are the initiatives of this organization, to inspire action to tackle the global sanitation crisis. 3. The main focus of its function is to grant funds to the least developed countries and developing countries to achieve the end of open defecation. Which of the statements given above is/are correct?

With reference to the role of biofilters in Recirculating Aquaculture System, consider the following statements: 1. Biofilters provide waste treatment by removing uneaten fish feed. 2. Biofilters convert ammonia present in fish waste to nitrate. 3. Biofilters increase phosphorus as a nutrient for fish in water. How many of the statements given above are correct?

Why is there a concern about copper smelting plants? 1. They may release lethal quantities of carbon monoxide into the environment. 2. The copper slag can cause the leaching of some heavy metals into the environment. 3. They may release sulphur dioxide as a pollutant. Select the correct answer using the code given below.

Magnetite particles, suspected to cause neurodegenerative problems, are generated as environmental pollutants from which of the following? 1. Brakes of motor vehicles 2. Engines of motor vehicles 3. Microwave stoves within homes 4. Power plants 5. Telephone lines Select the correct answer using the code given below.

‘Triclosan’, considered harmful when exposed to high levels for a long time, is most likely present in which of the following?

When reference to carbon nanotubes, consider the following statements: 1. They can be used as carriers of drugs and antigens in the human body. 2. They can be made into artificial blood capillaries for an injured part of the human body. 3. They can be used in biochemical sensors. 4. Carbon nanotubes are biodegradable. Which of the statements given above are correct?

Steel slag can be the material for which of the following? 1. Construction of base road 2. Improvement of agricultural soil 3. Production of cement Select the correct answer using the code given below:

With reference to chemical fertilisers in India, consider the following statements: 1. At present, the retail price of chemical fertilisers is market-driven and not administered by the Government. 2. Ammonia, which is an input of urea, is produced from natural gas. 3. Sulphur, which is a raw material for phosphoric acid fertilizer, is a by-product of oil refineries. Which of the statements given above is/are correct?

As per the Solid Waste Management Rules, 2016 in India, which one of the following statements is correct?

In the context of which one of the following are the terms ‘pyrolysis and plasma gasification’ mentioned?

In the context of solving pollution problems, what is/are the advantage/advantages of bioremediation technique? 1. It is a technique for cleaning up pollution by enhancing the same biodegradation process that occurs in nature. 2. Any contaminant with heavy metals such as cadmium and lead can be readily and completely treated by bioremediation using microorganisms. 3. Genetic engineering can be used to create microorganisms specifically designed for bioremediation. Select the correct answer using the code given below:

Consider the following pairs: Commonly used/ - Unwanted or consumed materials controversial chemicals likely to be found in them 1. Lipstick - Lead 2. Soft drinks - Brominated vegetable oils 3. Chinese fast - Monosodium food glutamate Which of the pairs given above is/are correctly matched?

With reference to ‘fly ash’ produced by the power plants using coal as fuel, which of the following statements is/ are correct? 1. Fly ash can be used in the production of bricks for building construction. 2. Fly ash can be used as a replacement for some of the Portland cement contents of concrete. 3. Fly ash is made up of silicon dioxide and calcium oxide only, and does not contain any toxic elements. Select the correct answer using the codes given below.

Brominated flame retardants are used in many household products like mattresses and upholstery. Why is there some concern about their use? 1. They are highly resistant to degradation in the environment. 2. They are able to accumulate in humans and animals. Select the correct answer using the code given below.

Improper handling and storage of cereal grains and oilseeds result in the production of toxins known as aflatoxins which are not generally destroyed by the normal cooking process. Aflatoxins are produced by:

Due to improper/indiscriminate disposal of old and used computers or their parts, which of the following are released into the environment as e-waste? 1. Beryllium 2. Cadmium 3. Chromium 4. Heptachlor 5. Mercury 6. Lead 7. Plutonium Select the correct answer using the codes given below:

What is the role of ultraviolet (UV) radiation in the water purification systems? 1. It inactivates/kills the harmful microorganisms in water. 2. It removes all the undesirable odours from the water. 3. It quickens the sedimentation of solid particles, removes turbidity and improves the clarity of water. Which of the statements given above is/are correct?

With what purpose is the Government of India promoting the concept of “Mega Food Parks”? 1. To provide good infrastructure facilities for the food processing industry. 2. To increase the processing of perishable items and reduce wastage. 3. To provide emerging and eco-friendly food processing technologies to entrepreneurs. Select the correct answer using the codes given below: