Question 97 from UPSC CSE 2015 - Current Affairs

Question

With reference to bio-toilets used by the Indian Railways, consider the following statements:
1. The decomposition of human waste in the bio-toilets is initiated by a fungal inoculum.
2. Ammonia and water vapour are the only end products in this decomposition that are released into the atmosphere.
Which of the statements given above is/are correct?

IASCODEX · Accepted Answer

Correct Option: D. Neither 1 nor 2

Strategy: Focus on the biological process used: Indian Railways' bio-toilets work via anaerobic bacteria (not fungi), ruling out Statement 1. For Statement 2, recall the process end-products: they release methane in addition to water vapor; ammonia is not the only gas produced. Thus both statements are factually incorrect.

Key Info: **Technology and Process**
Bio-toilets in Indian Railways use anaerobic bacteria, often developed by the Defence Research and Development Organisation (DRDO), to decompose human waste. The bacterial inoculum is strictly anaerobic and does not involve fungi. This process converts human excreta into simpler substances.

**End-Products**
The main end-products of the decomposition are:
- Methane gas
- Carbon dioxide
- Water

The methane can be collected or vented, while the water released is colorless and odorless. Ammonia, if present, is minimal and not a primary end-product.

**Benefits and Application**
The system provides an eco-friendly disposal method, which reduces manual scavenging and prevents track contamination. DRDO-developed bio-digesters are specifically designed for Indian field conditions, allowing their use in trains and other remote government sites.

IASCODEX · Answer

Option A: 1 only

IASCODEX · Answer

Option B: 2 only

IASCODEX · Answer

Option C: Both 1 and 2