The question asks about the scope of harmful effects of environmental pollution. To answer this, we need to consider all major components of the ecosystem that can be negatively impacted by pollution.
Correct Option: A) Plants, Animals and Human Beings. Environmental pollution has widespread harmful effects across the entire biological spectrum, impacting plants, animals (including humans), and microorganisms.
The question asks to identify a substance or phenomenon that can exist in solid, liquid, or gaseous states. We need to evaluate each option based on its physical states.
Correct Option: C) Pollutants can exist in solid (e.g., particulate matter, plastic waste), liquid (e.g., oil spills, chemical effluents), and gaseous (e.g., carbon monoxide, sulfur dioxide) forms, making this the most appropriate answer.
The question asks us to identify the correct statements regarding mercury pollution. We need to evaluate each statement individually based on general knowledge about environmental science and pollution sources.
Artisanal and small-scale gold mining (ASGM) is indeed the largest anthropogenic source of mercury emissions globally. Mercury is used in the amalgamation process to extract gold from ore. This mercury is then often burned off, releasing it into the atmosphere and contaminating water bodies and soil. This statement is correct.
Coal naturally contains trace amounts of mercury. When coal is burned in thermal power plants, this mercury is released into the atmosphere as a gaseous pollutant. These emissions are a significant global source of mercury pollution. This statement is correct.
While mercury is highly toxic, particularly methylmercury, and even low levels of exposure can be harmful, the statement "no known safe level" is a strong claim. Regulatory bodies and scientific organizations often establish reference doses or tolerable daily intakes for mercury, implying that there are levels below which adverse health effects are not expected. For example, the EPA and WHO have guidelines for mercury exposure. While minimizing exposure is crucial, stating there is "no known safe level" is generally considered an overstatement in a scientific context where thresholds are often defined, even if very low. Therefore, this statement is generally considered incorrect in the context of established scientific and regulatory thresholds.
B) Only two
Statements 1 and 2 are correct, while statement 3 is incorrect. Therefore, only two of the given statements are correct.
The question asks for the definition of a pollutant in terms of its concentration relative to a baseline. A pollutant is generally defined as a substance present in the environment at a level that causes harm, and this level is typically compared to what would naturally occur.
B) Natural Abundance — A pollutant is defined as a substance present in the environment in a concentration greater than its natural abundance, causing harmful effects to living organisms or the environment.
To determine how many more times an average human being requires air than food, we need to compare the typical daily intake of air (by weight or volume) with the typical daily intake of food (by weight).
Correct Option: A) 12-15 Times. An average human being requires approximately 12-15 times more air by weight than food. This figure is a widely accepted physiological estimate reflecting the continuous and voluminous nature of respiration compared to intermittent food intake.
The question asks about pollutants that cannot be degraded by natural processes and are harmful to what. This refers to non-biodegradable pollutants and their impact on biological entities.
Correct Option: D) Living Organisms. Pollutants that cannot be degraded by natural processes (non-biodegradable pollutants) are harmful to all forms of life, which are collectively referred to as living organisms. They can accumulate in the environment and food chains, causing toxic effects, diseases, and death across various species.