Indicators of Water Contamination
Microbial indicators are used in water quality testing to signal the potential presence of disease-causing microorganisms (pathogens). Their detection suggests that the water might be unsafe for consumption.
Role of Coliform Bacteria
- Coliform bacteria are frequently used as a primary indicator of potential fecal contamination in water supplies.
- Their presence suggests that the water may have been contaminated with the feces of humans or animals.
- While the coliform group includes bacteria that are often harmless, their detection flags the possibility that harmful pathogens might also be present.
- Testing for coliforms is a standard, cost-effective method for routine water quality monitoring.
Other Organisms and Water Safety
- Giardia and Cryptosporidium are specific protozoan pathogens that cause waterborne illnesses. While their presence indicates contamination and risk, they are not used as general *indicator* organisms in the same way coliforms are.
- Tobacco mosaic virus is a plant virus and is not relevant to the microbial contamination of drinking water.
Important Questions from Environmental Pollution and Control
A 500 MW coal based power station is operating at an efficiency of 30%. If the coal has 1% of sulphur content and 1 tonne of coal produces 8000 kWh energy, how much SO2 will be emitted daily by the plant?
Name the low heat thermal process that destroys the pathogen in biomedical waste by heating that occurs inside the waste material.
Arrange the following functional elements of solid waste management in the order in which they appear :
(i) On-site handling, storage and processing
(ii) Collection
(iii) Process recovery
(iv) Transfer and transport
Choose the correct answer from the code given below :
The dominant mechanism(s) of deposition of aerosol particles in the size range 5 -10 μm in the respiratory tract are
(i) Sedimentation
(ii) Impaction
(iii) Diffusion
Choose the correct answer from the code given below :
A tributary flowing at a rate of 4 m3/s converges into a river flowing at a rate of 8.0 m3/s. The concentration of a pollutant 'X' at the upstream of the tributary before convergence was 12 mg/L and that of the river was 30 mg/L. If the pollutant X is completely mixed in the downstream, what would be its concentration?
