How is chemical oxygen demand (COD) significant in assessing water quality?

Chemical oxygen demand (COD) is a crucial parameter in assessing water quality because it quantifies the amount of oxygen that is required to oxidize both organic and inorganic compounds in a water sample. This measurement is significant because it provides insight into the level of pollutants present in the water, which can impact the overall health of aquatic ecosystems.

High COD levels indicate a substantial presence of oxidizable substances, which can originate from various sources such as industrial discharges, agricultural runoff, and sewage. By quantifying COD, wastewater treatment facilities can gauge the effectiveness of treatment processes in breaking down contaminants and ensuring that the effluent released into the environment meets regulatory standards.

While factors like acidity, heavy metal presence, and biological activity are important in evaluating water quality, they are not directly measured by COD. Instead, COD focuses explicitly on the oxygen demand of substances that can be chemically oxidized, making it a vital indicator for assessing the potential impact of wastewater on the environment.