Water Filters
In 2006 about 4.5 billion people worldwide (64% of the global population) had access to piped water supply through house connections. Another 1.3 billion (20%) had access to safe water through other means than house connections, including standpipes, “water kiosks”, protected springs and protected wells. Finally, more than 1 billion people (16%) did not have access to safe water, meaning that they have to revert to unprotected wells or springs, canals, lakes or rivers to fetch water.
The World Health Organization has defined around 20 liters per capita per day as basic access, which implies high health concerns, and 100 liters per capita per day as optimal access, associated with low health concerns.
Both an adequate amount of water and adequate water quality are essential for public health and hygiene. Waterborne diseases are among the leading causes of morbidity and mortality in low- and middle-income countries, frequently called developing countries. For example, an estimated 900 million people suffer (and approximately 2 million die) from water-related diarrhoeal illnesses each year. At least 17 percent of the total burden of human diseases in many developing countries can be attributed to diarrhea and infestations by intestinal worms. The most common waterborne or waterwashed diseases are diarrhea, typhoid and cholera. Another example is trachoma, an infectious disease of the eye, which results in many cases of blindness in developing countries, which is associated with poor water supply, poor sanitation and failure to adequately process human excrement.
Water filters are primarily used to remove chemicals and metals such as chlorine and lead. Water filters can be used for health reasons in the case of harmful substances, or aesthetic reasons, to remove a disagreeable taste or smell.