Water is the only natural resource, both because it is necessary for the survival of humans and other organisms, and because, in the long range, in theory the total available amount of water in each area is approximately constant.

Water pollution and general pollution of water resources concerns for decades the international community. The water contamination by pathogenic microorganisms is the main problem in most underdeveloped and developing countries, while the chemical water pollution has emerged as an equally serious threat to all countries with agricultural and industrial development. The most important microorganisms in groundwater are pathogenic bacteria, fungi and other parasites.

The serious health problems caused by microorganisms underground water is typhoid, cholera and hepatitis. The sources of microorganisms are human and animal sewage and waste. The groundwater pollution caused by verses disposal of wastewater in urban wastewater treatment plants and septic tanks, washes from the dumps, and various agricultural practices such as land disposal of animal manure mulch. Substances with the greatest risk for our health, such as organic chemicals, heavy metals and micro-organisms, it is invisible, odorless and tasteless. The water filter systems are used to remove a wide range of water pollutants such as mentioned above. Asbestos contained in the water can be natural or be the result of pollution. Asbestos pollution in drinking water may come from surface water pollution as a result of production processes or the release of asbestos fibers from the pipes.

Consumers should be very careful and do a market research before deciding to purchase a filter, because each has specific standards and not all are suitable for all occasions and for all water qualities. Therefore it would be good to ask specialized technicians from official companies, taking into account the living area and the type and age of the dwelling and not to make hasty moves, guided only cost because more often than the cheap is the most expensive.