Question

According to the EPA of the USA, which of the following is not one of the six major pollutants?
A.Ozone
B.Carbon monoxide
C.Nitrogen oxides
D.Carbon dioxide

Answer 1

The addition of any unwanted material to air, water, and soil by natural source or due to human activity to such a level of concentration which adversely affects the quality of the environment is known as environmental pollution and the unwanted substances that are added to the environment are known as a pollutant.

Complete step by step answer:
EPA is an Environmental pollution Agency that looks after environmental protection measures. According to the EPA of the USA, the six major pollutants are given below:
Ground-level ozone
Nitrogen oxides
Carbon monoxide
Sulphur dioxide
Lead
Particulate matter
Hence we can say carbon dioxide is not considered to be six major pollutants according to the EPA of the USA.

Hence, option D is correct.

Additional information: Pollutants are classified into two different ways:
Primary pollutants: These are those which after their formation enter into the atmosphere and remain as such. For example sulphur dioxide, nitrogen dioxide and nitric oxide etc. nitric oxide becomes pollutant if this is present in excess in the environment.
Secondary pollutant: These are those harmful and unwanted materials which are formed by the chemical reactions between primary pollutants in the atmosphere. For example peroxyacyl nitrates etc.

Note:
There exists a permissible limit for a pollutant in the atmosphere to which there is no adverse effect on humans or animals and that limit is known as threshold limit value i.e. TLV. TLV for carbon monoxide (CO) is 40ppm whereas for the poisonous gas such as phosgene is only 0.1 ppm.