The article ‘Water – Liquid of Life’ in Nyam News Nos 1 & 2, August 2001, published by the Caribbean Food and Nutrition Institute contains information which many consumers would wish to have concerning home filtration and bottled water. Here we go:
“Home Filtration
“There are several types of water filtration systems now available for home use. Filters are membranes with pores in them with the size of the pores measured in macrons. (A macron is one millionth of a metre). The ability of a filter to remove contaminants such as solid minerals and chemicals – depends on the size of the pores. A one micron filter may filter out larger bacteria (e.g. Cryptosporidium) but leave behind smaller ones (which may measure an average of 0.5 microns), viruses (0.005 microns) and pesticides (0.00 microns). So, if you filter your water, you will want to check the size of the filter. All filters that have the words ‘reverse osmosis’ on the label protect against Cryptosporidium. The efficiency of filtration is increased when treated water is used. Treatment with chlorine is sufficient to kill most bacteria. Viruses are most difficult to eliminate.
“Bottled Water
“This is a general term used to describe several types of water. Bottled water or drinking water is water sealed in sanitary containers that meet all applicable standards. It cannot contain any chemical additives (other than very small amounts of flavorous, extracts or essences) or sweeteners and must be calorie-free and sugar-free. However, various kinds of bottled water are commercially available. These all have different standards for their packaging and labelling.
“Artesian Water comes from a confined underground source. The water is under pressure and rises above the water table.
“Deionized Water is water processed by highly reactive chemical resins which extract positive and negatively charged ionic particies such as calcium, sulphate, magnesium, iron, etc. The deionisation process does not remove toxic chemicals or bacteria.
“Distilled Water is water that has been evaporated and allowed to condense, resulting in the removal of all minerals and contaminants. Note that distillation is the only water purification method that removes l00 per cent of microorganisms and 99 per cent of other contaminants in the water.
“Purified Water is typically from the municipal supply, or groundwater treated by distillation, and deionization or reverse osmosis. Depending upon the water treatment process used the water may be labelled as distilled water, purified drinking water, distilled drinking water or deionized water.
“Mineral water is bottled water containing not less than 250 parts per million (ppm) of total dissolved solids (minerals and trace elements). Natural mineral water contains only the mineral present in the water as it flows from the ground. Mineral water not labelled “natural” may have had minerals added or removed.
“Reverse Osmosis is a method of using water pressure to purify water by passing it through a semi-permeable membrane that blocks the transport of salt and other solutes through it.
“Sparkling water contains naturally occurring or added carbon dioxide. The process of addition of CO2 is referred to as carbonization.
“The carbonization increases the acidity of the water, and this has a beneficial effect (i.e. it kills bacteria). Sparkling water is not to be confused with soda water, seltzer water or tonic water.
“Spring water comes from an underground source, flowing naturally to the surface. The water can be collected only at the spring or from a bore hole adjacent to the spring.
“Well water is brought to the surface by pumps from an aquifer (a water bearing rock or soil formation located underground)”
(To be concluded)
