UPSC Prelims 2012 Q15: Environment & Ecology – Pollution & Waste Management
Lead, ingested or inhaled, is a health hazard. After the addition of lead to petrol has been
banned, what still are the sources of lead poisoning?
1. Smelting units
2. Pens and pencils
3. Paints
4. Hair oils and cosmetics
Select the correct answer using the codes given below :
- (a) 1, 2 and 3 only
- (b) 1 and 3 only
- (c) 2 and 4 only
- (d) 1, 2, 3 and 4
Answer: (b) 1 and 3 only
Explanation
Sources of lead poisoning after leaded petrol was banned
| Source | A source of lead poisoning? (official key) | Fact |
|---|---|---|
| 1. Smelting units | Yes | Lead and zinc smelters and battery recycling units release lead fumes |
| 2. Pens and pencils | No | Pencil 'lead' is graphite, a form of carbon |
| 3. Paints | Yes | Lead pigments in enamel paints; old paint flakes and dust |
| 4. Hair oils and cosmetics | No | Not counted by the official key |
Effects of lead:
| Effect | Detail |
|---|---|
| Nervous system | A neurotoxin; lowers the intelligence of children |
| Blood | Causes anaemia |
| Kidneys | Long-term damage |
Steps taken in India: leaded petrol phased out by 2000; lead in household paints limited to 90 parts per million from 2017.
Answer: (b) 1 and 3 only.
Why each option is right or wrong
- (a) Incorrect. Pens and pencils are not a source; pencil lead is graphite.
- (b) CORRECT. Smelting units and paints remain sources of lead poisoning.
- (c) Incorrect. Pens and pencils and cosmetics are not the accepted sources.
- (d) Incorrect. Pens and pencils do not contain lead.
Key point
Lead sources today: smelters, battery recycling, lead-based paints, some pipes. Pencil 'lead' is graphite. Lead is a neurotoxin, worst for children.
Remember
Lead today: smelters and paints.
Common mistakes
- Believing that pencils contain lead.
- Forgetting battery recycling as a major source.
- Thinking the ban on leaded petrol ended lead exposure.
Exam tip
Pencil 'lead' is a misnomer. It is carbon.
Sources
- Ministry of Environment, Forest and Climate Change — Regulation of Lead Contents in Household and Decorative Paints Rules, 2016
- World Health Organization — Lead poisoning and health: fact sheet