Environmental Health

Step 1: Understanding pneumoconiosis.
Pneumoconiosis is a group of occupational lung diseases caused by long-term inhalation of mineral dust particles.
Step 2: Common causative agents.
Silica dust causes silicosis, coal dust causes coal workers’ pneumoconiosis, and asbestos causes asbestosis.
Step 3: Analyzing the options.
(A) Correct, inhalation of silica dust leads to silicosis, a type of pneumoconiosis.
(B) Incorrect, NO causes respiratory irritation but not pneumoconiosis.
(C) Incorrect, lead causes systemic toxicity, not lung fibrosis.
(D) Incorrect, cadmium affects kidneys and bones primarily.
Step 4: Conclusion.
Pneumoconiosis is caused due to inhalation of silica dust.

Step 1: Understanding lapse rate.
Lapse rate is the rate at which atmospheric temperature decreases with an increase in altitude. Ambient lapse rate refers to the actual temperature gradient of the atmosphere.
Step 2: Comparing with adiabatic lapse rate.
The adiabatic lapse rate represents the rate of temperature change of a rising or falling air parcel without heat exchange. When the ambient lapse rate is greater than the adiabatic lapse rate, the atmosphere becomes highly unstable.
Step 3: Analyzing the options.
(A) Incorrect, this is a standard adiabatic reference rate.
(B) Correct, exceeding the adiabatic rate is termed super-adiabatic.
(C) Incorrect, this applies to saturated air conditions.
(D) Incorrect, sub-adiabatic means less than adiabatic.
Step 4: Conclusion.
When the ambient lapse rate exceeds the adiabatic lapse rate, it is known as the super adiabatic lapse rate.