Primary pollutants are the pollutants those are directly released from a source where as a secondary pollutant isn't directly emitted as such but it forms when primary pollutants react in air.

These pollutants can be highly risky to the environment by causing Environmental shifts, Global warming etc. Some secondary pollutants and primary pollutants can be carcinogenic in nature which may lead to disease of cancer. Apart from this humans may face air pollution related diseases like Asthma to other environmental pollution hazards like Jaundice etc.

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