Lecture 08 - Water Treatment Flashcards
Why is water treatment necessary
to eliminate pathogens in water that pose an acute risk to human health
What is the main cause of diarrheal deaths
the use of unsafe water, improper sanitation or poor hygiene
What re DBPs
disinfection byproducts
How are DBPs formed
when disinfectants react with natural organic matter and contaminants in source water
What are the regulated DBPs
THMs, HAAs, bromate, chlorite, chlorate, NDMA
How do they analyze DBPs
samples are prepared and then separated by chromatography then put through mass spectrometry for detection and analysis
What trend do genotoxic and cytotoxic DBPs follow
iodinated > bromated > chlorinated
What association has been seen with DBP exposure
increased risk of bladder cancer, colorectal cancer, adverse reproduction/developmental outcomes
What are the main challenges in water treatment
- changes to source water
- changing chemical treatment practices
- challenges in the distribution system
What is the danger with reusing wastewater
effluent organic matter can promote the formation of nitrogen containing DBPs
Why are measurements taken at water treatment plants not always representative of water being used by end users
because DBPs can form from residual disinfectant reacting with pipe materials, biofilms, deposits, ect
