Question

which are invisible pollutants

Answer 1

The smallest particles can cross the alveolus-capillary barrier and make their way into the bloodstream. Invisible pollutants (nitrogen oxides,sulfur dioxide, volatile organic compounds, carbon monoxide) also pose a threat to health.

Answer 2

Invisible pollutants ( nitrogen oxide, sulphur dioxide, volatile organic compounds, carbon monoxide ) also pose a threat to health.

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