Most hazardous metal pollutant of automobile exhaust is

Options

A. Mercury
B. Cadmium
C. Lead
D. Copper

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the most hazardous metal pollutant of automobile exhaust.

2. **Recall the Common Pollutants**: In automobile exhaust, various pollutants are emitted, including carbon monoxide, nitrogen oxides, hydrocarbons, and heavy metals. Among the heavy metals, lead is a significant concern.

3. **Understand the Role of Lead**: Lead is released into the atmosphere primarily through the combustion of petrol, where it is used in the form of tetraethyl lead (C2H5)4Pb. This compound was commonly added to petrol as an anti-knock agent to improve fuel efficiency and reduce engine knocking.

4. **Explain the Hazards of Lead**: Lead is highly toxic and can cause severe health issues, including lead poisoning. This condition can affect multiple systems in the body, including the nervous system, liver, kidneys, and can even lead to brain damage.

5. **Discuss the Impact of Lead Poisoning**: In adults, lead can accumulate in the body, with typical levels ranging from 150 to 400 mg. Elevated blood lead levels (around 70 mg per 100 ml) can result from lead poisoning, leading to serious health consequences.

6. **Conclude the Answer**: Based on the information gathered, the most hazardous metal pollutant of automobile exhaust is lead (Pb).

**Final Answer**: The most hazardous metal pollutant of automobile exhaust is lead (Pb).

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