Microbiological Water Quality

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Microbiological Water Quality
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What Does Water Quality Mean?
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What Does Water Quality Mean?

• US Safe Drinking Water Act
• microbial contamination of drinking water not
  individually prioritized for regulation
• 0 pathogens (based on monitoring for fecal
  coliform indicators)

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What Does Water Quality Mean?

• US Safe Drinking Water Act
• microbial contamination of drinking water not
  individually prioritized for regulation
• 0 pathogens (based on monitoring for fecal
  coliform indicators)
• US EPA Surface Water Treatment Rule
• 99.9 reduction of Giardia and viruses
• Potable water is regulated by EPA (upper limit of
  500 cfu/ml, total count)
• Bottled water is food ? gt regulated by FDA
• may only contain safe and suitable
  antimicrobials and some fluoride
• requires membrane filtration assay or 10-tube MPN
  of 10 ten-mL samples

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What Does Water Quality Mean?

• EU standard
• 0 pathogens (based on total coliforms, fecal
  coliforms and total colony counts as indicators)
• UK singles out Cryptosporidium oocyst as a
  detection parameter for drinking water quality

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What Does Water Quality Mean?

• EU standard
• 0 pathogens (based on total coliforms, fecal
  coliforms and total colony counts as indicators)
• UK singles out Cryptosporidium oocyst as a
  detection parameter for drinking water quality
• Bottled mineral (non-carbonated) water
• naturally contains salts and microbes. Bugs
  survive bottling process.
• must be labeled appropriately
• un-altered levels of salts and microbes
• 1,000-10,000 CFU per ml
• (1 wk after bottling)

Diversity of microbes isolated from mineral
water, 3 weeks after bottling Loyet al., 2005
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Emerging Pathogens and Drinking Water

• The fear of cholera, typhoid fever have been lost
  in developed countries
• Emerging and re-emerging pathogens
• What are they?
• What are the factors that contribute to emergence
  and re-emergence?
• Pathogens in water distribution systems
• New kinds of pathogens
• Survival, lifestyle

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Drinking water as an ecosystem

• What are the biotic, abiotic pressures on
  microbes within drinking water distribution
  systems?
• K vs r-selected organisms. Who would do better?

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Biofilms in water distribution systems

• Structure
• Function