Question

In the following groups of materials, which group(s) contains only non-biodegradable items?

1. Wood, paper, leather
2. Polythene, detergent, PVC
3. Plastic, detergent, grass
4. Plastic, bakelite, DDT

• A. (iii)
• B. (iv)
• C. (i) and (iii)
• D. (ii) and (iv)

Answer 1

The correct option is D

(ii) and (iv)

The correct option is D.

The explanation for the correct option:

Biodegradable substances:

1. Biodegradable substances are defined as materials that get decomposed through natural processes by biological agencies like detritivores (bacteria, fungi, insects, worms, and some crustaceans).
2. They do not cause any pollution.
3. Examples: peels of vegetables and fruits, wood, paper, and grass.

Non-biodegradable substances:

1. Non-biodegradable substances are materials that cannot be degraded by natural agents like detritivores (bacteria, fungi, insects, worms, and some crustaceans).
2. They do not break down or dissolve for many years.
3. They are toxic and cause pollution.
4. Examples: plastic, Bakelite, insecticides like DDT, detergent, PVC, etc.
5. Plastic does not decompose well because it is not an organic material.
6. The majority of traditional plastics, like polyethene, are not biodegradable, posing a threat to the environment and the world as their collection grows.
7. DDT is harmful to all life on Earth since it cannot biodegrade and concentrates as it passes up the food chain.
8. Hence, from the above facts it is concluded that groups (ii) and (iv) contain non-biodegradable substances.

The explanation for the incorrect options:

Option A:

Out of Plastic, detergent and grass, grass is a biodegradable material as after some time it decomposes and mixes with soil. Whereas plastic and detergent are non-biodegradable.

Option B:

1. Polythene, PVC, and detergent are also non-biodegradable substances.
2. DDT is an organic compound that is odourless and colourless and is mostly employed as an insecticide in agricultural fields.
3. Since there is no feasible method for its decomposition by any means, they have now turned into a contaminant that affects environmental life forms and non-biodegradable substances.

Option C:

1. Wood is considered a renewable, sustainable, recyclable, cultivated nearby, adaptable, and biodegradable material that has lower energy, water, and carbon footprint during its life cycle than other products.
2. Paper is formed of generally biodegradable plant materials.
3. Leather has the potential to decompose because it is made from the collagen cells of animals.

Final answer: The group(s) that contains only non-biodegradable items is II. Polythene, detergent, PVC and IV. Plastic, bakelite, DDT.