Consider the statement: “Carbon monoxide is a common atmospheric pollutant.” With reference to environmental science, is this statement correct or incorrect?

Introduction / Context:
Carbon monoxide (CO) is a colourless, odourless gas produced primarily through incomplete combustion of carbon containing fuels such as petrol, diesel, coal, and wood. Understanding whether CO qualifies as a common atmospheric pollutant is crucial for environmental science and general awareness because it directly affects air quality and human health. The question presents a statement about carbon monoxide and asks whether it is correct or incorrect.

Given Data / Assumptions:

• The statement under evaluation is: “Carbon monoxide is a common atmospheric pollutant.”
• The term “atmospheric pollutant” here refers mainly to pollutants found in ambient air, both outdoor and, by extension, indoor environments.
• Sources of CO are primarily vehicle exhausts, industrial processes, residential burning of fuels, and other combustion activities.
• We assume standard textbook definitions of air pollutants and common knowledge about urban air pollution.

Concept / Approach:
In environmental science, an air pollutant is any substance present in the atmosphere at concentrations high enough to harm humans, animals, vegetation, or materials. Carbon monoxide fits this definition because it is frequently detected in urban air, especially near traffic junctions and enclosed parking areas, and it can interfere with the oxygen carrying capacity of blood. Therefore, the approach is to evaluate whether CO is indeed common and whether it is recognised as a pollutant in air quality standards.

Step-by-Step Solution:
Step 1: Recall that carbon monoxide is produced by incomplete combustion, which occurs in many everyday situations such as vehicle engines and household fuel burning.Step 2: Recognise that these sources are widespread, especially in cities and industrial regions, so CO is present in the atmosphere at significant levels.Step 3: Air quality monitoring agencies include carbon monoxide among the standard pollutants they track, confirming its status as a recognised pollutant.Step 4: Because of its toxicity and broad occurrence in outdoor and indoor air, carbon monoxide clearly qualifies as a common atmospheric pollutant.Step 5: Conclude that the statement given in the question is correct and select “Correct” as the answer.

Verification / Alternative check:
Verification can be done by recalling that ambient air quality standards in many countries, including India, specify permissible limits for carbon monoxide. Environmental reports often list CO along with other key pollutants such as particulate matter, nitrogen oxides, and sulphur dioxide. These documents describe typical levels of CO in urban atmospheres and sometimes highlight episodes where it exceeds safe limits. All of this confirms that carbon monoxide is recognised as a common atmospheric pollutant.

Why Other Options Are Wrong:
Option B (Incorrect) is wrong because it would imply that carbon monoxide is not a pollutant, which contradicts scientific and regulatory consensus. Option C (Only correct for indoor air, not for outdoor air) is incorrect because CO is present in both indoor and outdoor environments, particularly near traffic and combustion sources, and is monitored in outdoor air quality as well. Option D (Cannot be determined from the given information) is also wrong, because basic environmental science clearly establishes CO as a pollutant and the statement provides enough context to decide.

Common Pitfalls:
A common pitfall is to think that only visible pollutants like smoke or dust qualify as atmospheric pollutants, leading some people to underestimate invisible gases such as carbon monoxide. Another mistake is to believe that CO is mainly an indoor hazard related to faulty heaters, ignoring its role in outdoor air pollution. To avoid these errors, students should remember that both indoor and outdoor sources of CO contribute to its status as a common atmospheric pollutant.

Final Answer:
The correct answer is Correct. The statement “Carbon monoxide is a common atmospheric pollutant” is accurate in the context of environmental science.