Ch 8.3-8.7, 8.9 Flashcards
(29 cards)
three categories of pathogens that produce water-borne diseases
Parasite
Bacteria
Virus
Pathogenic
Disease-causing
Parasite example
Giardia
Source = fecal contamination & uncooked food
Health problems = vomiting, diarrhea, & cramps
Bacteria example
E.coli
Source = fecal contamination
Health problems = diarrhea & cramps
Virus example
Polio
Source = fecal contamination
Health problems = flu symptoms & paralysis
What to avoid when traveling to places w/ no comprehensive water sanitation procedures
Ice
Tap water
Vegetables & fruits that don’t have a peel
Potable
Means drinkable
Boiling water
Kills bacteria, viruses, & protozoa
Boil for 1 min (3 min for altitude > 5,000ft)
This does not destroy heavy metals, salts, & other chemicals
Disinfecting water at home
A diluted form of liquid chlorine (household) bleach (don’t use color safe or scented)
Or ammonia
NEVER BOTH AT ONCE
Contaminant
Any physical, chemical, biological, or radiological substance or matter in water
Anything other than water molecules
Combustion sources & how combustion processes affect water sources
Sources = vehicles & power plants
They combust fossil fuels & generate compounds NOxs, SOxs, CO, & CO2 and some of these compounds become soluble in water
Result = affects pH (pH < 5.6 = acid rain)
Acid rain
Involves sulfuric, nitric, and carbonic acids
Affects living organisms & building materials
Can corrode metals & make them soluble too
Northeast US = most problems w/ acid rain (dense population, lots of cities)
Inorganic contaminants
Hard water
Soft water
Eutrophication
Lead
Arsenic
Mercury
Cadmium
Uranium
Hard water
Large concentration of minerals
Ions = calcium, magnesium, carbonate, & iron
Not toxic but can affect industrial processes
Scale = building up of new formed solid ions (can damage equipment internally)
Can contribute to formation of kidney stones
Soft water
Potassium & sodium ions present
Does not form scale
Does produce excessive lathers w/ soap
Preferred over hard water but sodium content can affect if ingested at high concentration
Eutrophication
When an excessive amount of nitrites (fertilizer) or phosphates dissolve in water & these chemicals then activate plants/algae to grow
Leads to overgrowth in plant life which can inhibit oxygen from entering the water (can kill aquatic animals)
Toxic inorganic species
Lead = construction work
Arsenic = waste sites
Mercury = fish
Organic chemical concerns
Dioxin = byproducts of industrial practices produced by incineration processes & can be released into air during forest fires
Persistent Organic Polluters (POPS) b/c of their long residual life-times
Fat soluble which affects health of living organisms
Harms hormonal & reproductive systems
PCBs = carcinogen, used to be electrical insulators
Why drinking water requires sanitation
Sanitation = disinfects water & kill germs
3 types of water sanitation methods
Chlorine-based
Ozone disinfection
UV radiation
Chlorine methods
Rids water of bacteria & viruses (not parasite)
Offers residual protection from treatment facility to consumer
Alters taste & smell
Possible disinfectant byproducts
Residual protection
Low level of chlorine remaining in water after its initial application
Ozone disinfection
Toxic to most waterborne organisms
Kills viruses & bacteria
Does not alter the taste or smell
No residual protection
Fewer disinfectant byproducts
Most expensive method
Disinfectant byproducts
New compounds formed by chemical compound used to sanitize water
Can be a primary contaminant
