Source: HT
Context: High levels of fecal coliform bacteria were detected in the Ganga and Yamuna rivers at Prayagraj during Maha Kumbh 2025, as per a CPCB report submitted to NGT.
About Fecal Coliform:
- What it is?
- A subgroup of coliform bacteria that primarily originate from the intestinal tracts of warm-blooded animals, including humans.
- Limit: The Central Pollution Control Board (CPCB) standards have set a permissible limit of 2,500 units of faecal coliform per 100 ml of water, while for drinking water, E. coli must be absent.
- Types of Bacteria: Includes Escherichia coli ( coli), with certain strains like E. coli O157:H7 being harmful and capable of causing intestinal infections.
- What its Presence Indicates?
- Sewage contamination of water sources.
- Potential presence of disease-causing pathogens such as those responsible for typhoid, hepatitis A, and gastroenteritis.
- Poor waste management, leakage from septic systems, or agricultural runoff polluting water bodies.
- Impacts of Fecal coliform on BOD and COD:
- BOD Increase: Fecal coliform bacteria decompose organic waste, consuming dissolved oxygen and raising Biochemical Oxygen Demand (BOD), leading to oxygen depletion and aquatic life suffocation.
- COD Increase: Contaminants from sewage and industrial discharge raise Chemical Oxygen Demand (COD), indicating non-biodegradable pollutants, lowering water quality and harming ecosystems.
