Q. Which of the following pollutants are notified under “National Ambient Air Quality Standards (NAAQS)”?
1. Sulphur Dioxide
2. Nitrogen Dioxide
3. Benzene
4. Ozone
5. Lead
Select the correct answer using the code given below: 
Answer: D
Notes:
National Ambient Air Quality Standards (NAAQS) were notified in the year 1982, duly revised in 1994 based on health criteria and land uses.
The NAAQS have been revisited and revised in November 2009 for 12 pollutants, which include
- sulphur dioxide (SO2),
- nitrogen dioxide (NO2),
- particulate matter having size less than 10 micron (PM10),
- particulate matter having size less than 2.5 micron (PM2.5),
- ozone,
- lead,
- carbon monoxide (CO),
- arsenic,
- nickel,
- benzene,
- ammonia, and
- benzopyrene.
Source: The Hindu
