Water Quality
The taste and smell of water is not necessarily related to its safety. Many contaminates are tasteless and odorless while many tastes and odors are caused by harmless substances.
Asking members of the public is not a reliable way to determine the safety of a water source.
Lack of acute symptoms does not mean that the water is safe. For example heavy metals and organic compounds can build up in the body over time while any health problems progress slowly.
The term organic in relation to water treatment refers to the chemistry of carbon compounds, usually artifically produced, and has a different meaning than the word organic used in organic farming or organic food.
Distillation involves boiling the water to produce water vapour. The vapour contacts a cool surface where it condenses as a liquid. Because the solutes are not normally vaporised, they remain in the boiling solution. Even distillation does not completely purify water, because of contaminants with similar boiling points and droplets of unvaporised liquid carried with the steam. However, 99.9% pure water can be obtained by distillation. Distillation does not confer any residual disinfectant and the distillation apparatus may be the ideal place to harbour microorganisms such as Legionnaires' disease.
The initial source of the water by itself does not determine the quality of water coming from a treatment facility. Water sourced from a poluted source can be made safe if the water treatment facility is designed to handle the contamination. For example there are "toilet to tap" water systems that can convert raw sewage into safe drinking water. Poluted source water becomes a serious issue when there is a new contaminate or higher levels of contamination that the treatment system was not originally designed to handle, e.g. a spill of chemicals or sewage into a source river.
Activated charcoal removes dissolved chemicals from water. The activated charcoal must be replaced periodically to be effective. The activated charcoal removes chlorine so water treatment plants add chlorine after activated charcoal treatment. Some filters have activated charcoal and are often called charcoal filters but the activated charcoal in the filter is not itself a filtering material and does not filter out particulate matter. Using charcoal to treat tap water can be bad because removal of the chlorine can make the water susceptible to microorganisms particularly if the water must travel through more plumbing or is stored.
Purchased bottle water does not usually have chlorine and once opened should be used before it becomes contaminated.
Filters remove suspended particles including some microorganisms. Most filters cannot remove dissolved chemicals nor heavy metals.
There are filters available that will remove almost everything but usually microorganisms and viruses are killed using an added chemical, boiling or UV light. Chemicals such as chlorine or iodine have the advantage over UV and boiling in that they will continue to protect the water as it flows through plumbing or while in storage.
Boiling water only kills microorganisms and viruses but will not remove contaminates.
Few water systems use lead pipes for supply however there are still many supply lines in service that have lead in the joints. Flowing water tends not to absorb lead and the water often becomes contaminated when it sits still in the pipes near the user in the home or business. Letting a tap flow for two minutes will flush out the stagnate water and reduce the lead contamination caused by lead in pipe joints.
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