Biochemical Oxygen Demand measures the oxygen required by aquatic microorganisms to decompose organic material in water. Which pollutant measure is this?

Biochemical Oxygen Demand measures the oxygen required by aquatic microorganisms to decompose organic material in water. Which pollutant measure is this?

• A. Dissolved inorganic carbon
• B. Water hardness
• C. Biochemical Oxygen Demand
• D. Salinity

Answer: (C)

The concept being tested is how we quantify organic pollution in water by looking at how much oxygen microorganisms will use to break it down. Biochemical Oxygen Demand is the measurement that captures this: it tells you how much oxygen would be consumed by microbes to decompose biodegradable organic matter under standard conditions. That’s why it’s used as an indicator of organic pollution and the potential for oxygen depletion in a water body. Dissolved inorganic carbon measures inorganic carbon species, not the oxygen demand from organic matter. Water hardness relates to calcium and magnesium ions, not oxygen consumption. Salinity is about the overall salt content. So Biochemical Oxygen Demand uniquely reflects the oxygen needed to break down organic pollutants, which is why it’s the correct measure.

The concept being tested is how we quantify organic pollution in water by looking at how much oxygen microorganisms will use to break it down. Biochemical Oxygen Demand is the measurement that captures this: it tells you how much oxygen would be consumed by microbes to decompose biodegradable organic matter under standard conditions. That’s why it’s used as an indicator of organic pollution and the potential for oxygen depletion in a water body.

Dissolved inorganic carbon measures inorganic carbon species, not the oxygen demand from organic matter. Water hardness relates to calcium and magnesium ions, not oxygen consumption. Salinity is about the overall salt content. So Biochemical Oxygen Demand uniquely reflects the oxygen needed to break down organic pollutants, which is why it’s the correct measure.