The present of which bacteria is an indicator of water pollution?

Correct option is B

(b) E. coli coliform

Explanation:

• The presence of E. coli (Escherichia coli), a type of coliform bacteria, is a strong indicator of water pollution, particularly contamination from fecal matter. E. coli is commonly found in the intestines of warm-blooded animals, including humans. Its presence in water suggests contamination from sewage or animal waste, which may also carry harmful pathogens.
• Other bacteria like Mycobacterium tuberculosis, Salmonella typhi, and Vibrio cholerae are disease-causing agents but are not specifically used as indicators of water pollution. These bacteria may be present in polluted water, but E. coli is the standard indicator due to its higher association with fecal contamination.

Important Key Points:

1. E. coli is a primary indicator of fecal contamination in water.
2. Its presence suggests possible pathogens like viruses, bacteria, and parasites in water.
3. Regular testing for E. coli helps monitor water quality and safety.
4. Salmonella and Vibrio cholerae cause diseases but are not standard indicators of water pollution.
5. Coliform bacteria are used as general indicators of water pollution.
6. Clean water standards require the absence of E. coli in drinking water.

Information Booster:

• Mycobacterium tuberculosis: Causes tuberculosis, typically affecting the lungs.
• Salmonella typhi: Causes typhoid fever, commonly spread through contaminated food or water.
• Vibrio cholerae: Causes cholera, often contracted by drinking contaminated water.