136. Common indicators of water pollution with enteropathogens are following EXCEPT-
(a) Bacillus spp.,
(b) Clostridium spp.,
(c) E. coli,
(d) Streptococcus spp

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Understanding Water Pollution and Enteropathogens

Water pollution caused by enteropathogens is a serious environmental issue. These harmful microorganisms contaminate water sources, leading to various health risks, including gastrointestinal infections. Enteropathogens can originate from human or animal fecal matter, and identifying them is essential to ensuring water safety. Among the most commonly used indicators of water contamination are species like E. coli, Bacillus spp., and Clostridium spp. However, Streptococcus spp. is not typically considered a reliable indicator of water pollution in this context.

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Common Indicators of Water Pollution with Enteropathogens

Enteropathogens that indicate water pollution are typically organisms associated with the presence of fecal contamination, signaling potential health hazards. Here’s a closer look at the most common indicators:

1. E. coli:

   • Escherichia coli (E. coli) is the most widely known and studied indicator of fecal contamination. Certain strains of E. coli, such as E. coli O157:H7, can cause severe gastrointestinal illness and are often used as markers for waterborne disease outbreaks.

2. Bacillus spp.:

   • Bacillus species are another common group of bacteria that can be used to indicate water pollution. Some species, such as Bacillus cereus, can cause food poisoning, and their presence in water suggests the possibility of contamination by fecal matter or other organic waste.

3. Clostridium spp.:

   • Clostridium species are anaerobic bacteria that thrive in low-oxygen environments, including those found in sewage. Clostridium perfringens, in particular, is frequently used as an indicator of water contamination, as it can be found in both human and animal feces.

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Why Streptococcus spp. Is Not Typically Used for Water Pollution

While Streptococcus spp. are part of the normal microbiota of the human and animal intestines, they are not as commonly used as indicators of enteropathogenic water pollution. This is because:

• Streptococcus spp. are more often associated with other types of infections, such as throat infections or skin diseases, rather than being a direct indicator of water contamination.

• Although certain strains of Enterococcus faecalis, a member of the Streptococcus genus, are sometimes used in water quality testing (especially in recreational water), the broader genus Streptococcus does not serve as a common or reliable marker for enteric pathogens.

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Conclusion

Among the most common indicators of water pollution with enteropathogens, E. coli, Bacillus spp., and Clostridium spp. are typically used in water quality testing due to their strong association with fecal contamination. However, Streptococcus spp. is not typically considered a reliable indicator of waterborne diseases related to enteropathogenic pollution.

Correct Answer:

(d) Streptococcus spp.