3. 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

1. 1, 2 and 3 only

2. 1 and 3 only

3. 2 and 4 only

4. 1, 2, 3 and 4

Correct Answer :

1 and 3 only