Potable water
Common obstacles of this system: Particulates & Sediments
- block UV rays from passing through water - act as shield for germs - suspended solids should be physically removed before water goes through system
Response to health risks
- bottle water phenomenon - home filters ie. Brita - in-line systems using UV light or reverse osmosis filtration - ceramic filtrations
Common obstacles of this system: Iron/manganese
- cause discolouration on quartz sleeve - reduces transmission of UV light/absorb UV energy - should be removed pre-treatment, or reduce to no more than .3ppm & 0.05 ppm
Controversies & support
- chemicals found in tap water are very common - over 2000 diff types of toxic chemicals - owning water purification very important
Chemicals with tap water
- enter through many sources ie. pollution - by public water systems ie. chlorine (most common, to kill bacteria)
Artesian & spring
- filtered by the earth - contains wide variety of trace - emerge from aquifer by own pressure - comes from well that taps a confined aquifer
Health risks from chemicals: Chlorine
bladder & rectal cancers, asthma, breast cancer (recently)
Health risks from chemicals: Lead
harmful for pregnant mothers & children, cause learning disorders & severe development delays
Health risks from chemicals: Giardia & Cryposporidium
protozoa that cause GI disease outbreaks (make way in water system when there's sanitation breakdown)
Potable water definition
water fit for consumption by humans and other animals; free from harmful contaminants
Confined aquifer
water-bearing underground layer of rock/sand which water level is above top of aquifer
Is Reverse osmosis the best technology?
- ability to filter minute particulate Long term health risks: - Demineralization of the water->more acidic - low mineral water increased diuresis 20% on average & increased elimination of sodium, potassium, chloride, calcium and magnesium ions from body (WHO)
Developed countries with common water for public consumptio
- Regulated sources of water provided by water mains - Tested, filtered, treatment - Enriched by substances for hea
Reverse Osmosis
- forcing water through a semi-permeable membrane, which filters out select number of water contaminants depending on size of contaminant *Contaminants larger than water molecules -> filtered out *Contaminants smaller -> remain in the drinking water
The threat to health concerning non-potable water is the contamination with:
- microbes - heavy metals - waste
UV Light Water Purification
- most effective method for disinfecting bacteria from water - penetrate harmful pathogens in home's water & destroy illness-causing microorganism by attacking their genetic core (DNA)
Health risks from chemicals:
- overtime, chlorine in small doses increase risk of cancer, heart disease & other health conditions 1) Chlorine 2) Lead 3) Giardia & Cryposporidium
Personal/non urban filtration options
- prevail in camping equipment market - filter solutions created for use in supporting emergency/crisis workers
Limitations with other organic/inorganic dissolved substances
- reduce germicidal effectiveness of UV light - should be pretreated before UV unit
Limitations when water is hard
- scale will build up on quartz sleeve around UV lamp-> stops UV from passing through - water softener should be used before UV unit
Contaminants in tap water:
- toxic metal salts - hormones & pesticides - may become contaminated by chemicals or microbes within pipes (ie. lead, bacteria, protozoa)
Tap Water
- treated with large number of chemicals in order to kill bacteria & other microorganisms
Waterborne disease
- world's leading killer (WHO) - 3.4 mill die as result of organisms/raw sewage contamination - 4,000 children day each day as result of ingestion - 4 out of 10 ppl in world do not have clean water to drink
The only healthy and safe way to drink ordinary tap water:
To use a water purification