Atmospheric carbon monoxide concentration becomes harmful at

Options

A. 0.5 , 2mm Hg
B. 0.4 , 7mm Hg
C. 0.3 ,5mm Hg
D. 0.1, 0.7 mm Hg

Answer

To determine the harmful concentration of atmospheric carbon monoxide, we can follow these steps:

### Step 1: Understand Carbon Monoxide
Carbon monoxide (CO) is a colorless, odorless gas that is produced by the incomplete combustion of carbon-containing fuels. It is known to be lethal at certain concentrations.

**Hint:** Remember that CO is produced from burning fuels and is dangerous because it is colorless and odorless.

### Step 2: Effects of Carbon Monoxide
High levels of carbon monoxide in the atmosphere can lead to serious health issues. It binds with hemoglobin in red blood cells more effectively than oxygen, reducing the amount of oxygen that can be transported throughout the body. This can lead to symptoms like headaches, dizziness, nausea, and even unconsciousness.

**Hint:** Think about how CO affects oxygen transport in the body and the symptoms that arise from reduced oxygen levels.

### Step 3: Identify Toxic Concentration Levels
The question provides multiple options for the concentration of carbon monoxide that becomes harmful. According to the information, a concentration of 0.1 to 0.7 millimeters of mercury (mmHg) is considered toxic.

**Hint:** Focus on the specific range provided in the video transcript that indicates when CO becomes harmful.

### Step 4: Choose the Correct Option
From the options given:
- 0.5 or 2 mmHg
- 0.4 or 7 mmHg
- 0.3 and 5 mmHg
- 0.1 and 0.7 mmHg

The correct answer is **0.1 to 0.7 mmHg**, as this range is identified as toxic.

**Hint:** Look for the range mentioned in the transcript that specifies toxicity.

### Final Answer
The atmospheric carbon monoxide concentration becomes harmful at **0.1 to 0.7 millimeters of mercury**.

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