Water intended for human consumption must not contain chemicals and micro-organisms in quantities that may affect health. It must be safe and harmless to health, not cloudy and free of color and unpleasant odor and taste. It must be safe and harmless to health, not cloudy and colorless and unpleasant smell and taste.The location, construction, operation and supervision of a water source (springs, tanks, water treatment and distribution) must be such as to exclude any pollution of water. Most countries in the world have established drinking water quality standards in their territory and use methods of analyzing and expressing similar results to make it easy to compare. In addition, epidemics of water-borne diseases can be avoided if strict controls are carried out by the water authorities and health authorities regarding the quality of drinking water. According to the Sanitary Regulation, “drinking water” means water used for human consumption, whether pre-treated or not, whatever its origin.LEGISLATION
The Sanitary Regulation for Drinking Water, in force today (A5 / 288 / 23-1-86 GG53 / Issue B / 20-2-86) is in line with Council Directive 80/778 / EU.
It contains 62 parameters classified into five basic groups:
Organoleptic – Physicochemical – Undesirable – Toxic – Microbiological. “Indicative Level” (EU) and “Maximum Acceptable” are set for each parameter.
Concentration ”(APS). Article 5 (2) states that the values of the drinking water quality parameters must in any case be lower than or equal to the MRL. and to approach the EU. Derogations from these values are permitted in exceptional cases (set out in Articles 7 and 8 of the Health Order), but they do not pose a risk to Public Health. Annex II sets out the parameters to be taken into account for controls and the frequency of standard analyzes. Article 11 of the Order stipulates that the “Competent Authority” for its implementation are the Health Services of the Ministry of Health, Welfare and Social Security, which control the “Responsible” for compliance with the terms of the Health Order. “Responsible” for the design, construction, operation, cleaning of water systems, monitoring of drinking water quality and generally for taking measures to ensure the regular supply of healthy water on a permanent basis are:
For Municipalities and Communities, the respective Organization or Business or
Link.For industries, institutions etc., which have their own water supply, their legal representatives.
Finally, Annex III sets out the analytical reference methods for the determination of the 62 parameters listed in the Sanitary Regulation.
HYGIENE IMPORTANCE OF CHEMICAL PARAMETERS
If the results of chemical analyzes in a water exceed the upper limit
acceptable concentrations specified by the Health Order, then or water is judged
inappropriate or take measures to clean it (eg chlorination, sedimentation, source protection).
A. ORGANIZATIONAL PARAMETERS
Color
If present, it is undesirable for drinking water and may be due to the presence of dissolved pigments, either from plant roots, tree leaves, or organic or inorganic (salts, corrosion iron). The presence of color in the water does not mean that it is always dangerous. It has to be chemically examined to trace the origin of the color. No permissible limit for color in drinking water is proposed.
Turbidity
It is due to solids that are suspended inorganic or organic matter. Water that is
cloudy should be checked for contamination. The suspended solids also precipitate
cause problems in pipelines and tanks. Consuming canopy water can be hazardous to health. Drinking water disinfection is not effective if there is cloudiness, as many pathogens are trapped in particles that are suspended and protected by the disinfectant. Particles can also absorb harmful organic or inorganic substances. Drinking water should be clear when it reaches the consumer.
Odor – Taste
Drinking water must be odorless and tasteless. All waters are special
their taste due to their dissolved salts and their dissolved gases. Flavor and odor in water are usually not considered important from a health point of view. But it is not desirable in drinking water because it is usually due to either chemicals or microorganisms. Water with a strong odor may be contaminated, so it must be examined to find the cause, especially if there is a sudden change.
B. PHYSICOCHEMICAL PARAMETERS
Temperature
The temperature of the water affects its taste. As the temperature rises
water is less delicious because the gases dissolved in it are expelled. The most
pleasant taste is between 5-15 ° C (mainly 9-10 ° C). When the temperature of the water exceeds 15 ° C the germs that multiply may multiply. It also reduces its ability to dissolve gases, while solubility in solids increases, or biological activities accelerate. It also increases the amount of chlorine required and favors the growth of algae resulting in the appearance of unpleasant odors and flavors.
Conductivity
Conductivity is the numerical expression of the capacity of an aqueous solution
to conduct electricity. This ability depends on the presence of ions, their total concentration, their strength and their individual concentrations, and the measurement temperature. Water conductivity increases with temperature.
Chlorides (Cl-). They are widely used in nature as sodium, potassium and calcium salts. They come from the erosion of rocks. Because they are highly mobile and easily soluble they enter the land or are transported in closed tanks and oceans. However, they may result from the use of fertilizers, sewage and industrial waste or seawater penetration in coastal areas. They have no harmful effect on the human body, but on high ones
Concentrations give the drinking water a sweet taste. The sharp increase in chlorine in the water, if not due to seawater entry, indicates possible sewage pollution and requires an immediate on-site health inspection. Contamination must be confirmed by other measurements (microbiological, ammonia, nitrite). Since no human chlorine toxicity has been observed in humans, a maximum level in drinking water has not been established.
Calcium (Calcium – Ca)
It is found in all natural waters and comes from rocks (limestone, dolomite, gypsum) through which water passes. The calcium concentration
varies from zero to a few hundred mg / l depending on the origin of the water and contributes to its overall hardness. It has no adverse health effects.
Magnesium (Magnesium – Mg)
It is abundant in nature (eighth in a row) and is one of the common ingredients of natural waters. Its salts together with calcium constitute the total hardness of the water and when heated they form pipes and boilers. Waters with magnesium concentrations greater than 125 mg / l may have laxative and diuretic properties.
Hardness
Hardness expresses the total dissolved calcium and magnesium salts
and depends on the rocks that have passed through the water. It is distinguished by carbonate (or transient) hardness due to acidic (bicarbonate) salts and non-carbonate (permanent) hardness due to other salts (chloride, sulphate, nitrate, carbonate). High hardness values do not pose a health risk; however, a significant correlation has been found between increased hardness and a decrease in cardiovascular disease. Hardness is also desirable in brewing and baking because it aids enzymatic activity. Hard water does not taste good, it prevents the food from boiling, does not foam with soap and creates pipes and household appliances. Also in some industries (tanneries, dyes, chemicals and pharmaceuticals) hard water is detrimental to the treatment and the finished product. Water with a hardness up to 500 mg / l CaCO3 can be used for drinking, but the best values are between 80 and 150.
Sodium (Sodium – Na)
It is a key element for man. Sodium salts are found in all foods and drinking water. Due to its abundance in nature (sixth in a row) it is found in all natural waters at concentrations ranging from 1-500 mg / l. In drinking water it does not exceed 20 mg / l, except where it has been softened by the ion exchange method in waters with high hardness. At concentrations greater than 200 mg / l it affects the taste of water. Sodium (mainly its ratio to other cations in water) is of great importance for agriculture and human pathology. Soil permeability is adversely affected by a high proportion of sodium in the water. People suffering from chronic heart disease need low sodium water. There are epidemiological studies reporting health effects of high sodium concentrations in drinking water, but existing data cannot conclusively draw conclusions about the relationship of sodium to water and the development of hypertension.
Potassium (Potassium – K)
It is the seventh element in abundance in nature. Therefore, it is found in all natural waters. Rarely does the drinking water content reach 20 mg / l of potassium. No adverse health effects have been reported.
Dissolved Oxygen
The dissolved oxygen content of the water should be at the saturation point, ie 100%, so the water has a pleasant taste. No health effects have been directly linked to the reduction or lack of dissolved oxygen in drinking water. However, there are some indirect effects: Pipes are corroded resulting in increased water content of metals (eg iron, zinc, lead, cadmium). Anaerobic conditions are also created which help to reduce nitrates to nitrates, sulfates to sulfates, resulting in the production of unpleasant odors. Dissolved oxygen decreases as water temperature and salinity increase.
C. PARAMETERS CONCERNING UNDESIRABLE SUBSTANCES
Nitrogen compounds (Ammonia-Nitrite-Nitrates / Nitrogen compounds: Ammonia – Nitrites – Nitrates)
The determination of the various nitrogen compounds in drinking water is an indicator of the health quality of the water. Prior to the development of bacteriological analyzes, the measurement of nitrogen compounds in water was the only indicator of possible contamination. In freshly polluted waters, nitrogen is in the form of organic nitrogen and ammonia. As time passes, the organic nitrogen is gradually converted to ammonia and later, if aerobic conditions are present, the ammonia is oxidized to nitrite and nitrate. On the basis of the above, waters containing high amounts of organic nitrogen and ammonia are considered to have been recently polluted and therefore present a high risk to public health. Waters containing nitrogen in the form of nitrates means that they have been contaminated long ago and therefore do not pose an immediate threat to public health.
Ammonia (NH3).
Groundwater usually contains less than 0.2 mg / l ammonia. Higher concentrations are observed in forest soils. Ammonia does not directly affect health at concentrations that may be present in drinking water, but is an important indicator of fecal contamination. At concentrations greater than 0.2 mg / l it causes odor and taste problems in the water and reduces the efficiency of disinfection. It also contributes to the formation of nitrides in water systems.
Nitrite (NO2) – Nitrate (NO3).
They are part of the nitrogen cycle in nature, so they exist in natural waters, but the nitrate concentration is usually low. High concentrations are due to fertilizers, waste and animal or human waste. They are even present in the air due to air pollution, so they are drifted by rain or deposited on the ground. In aerobic conditions nitrates penetrate the aquifer. Drinking water containing large amounts of nitrate may cause children to develop methemoglobinemia due to their reduction to nitrite.
Iron (Iron – Fe)
It exists mainly in groundwater, passing through rocks rich in iron salts. Continuous consumption of water with high concentrations of iron can cause tissue damage (hemochromatosis) in humans, and especially children. Iron gives water a taste that is detectable at very low concentrations. Iron in water causes problems in washing machines and weavers (stains are created in fabrics) and in water distribution pipes (favors bacteria growth and deposits are created).
Manganese (Mn)
Harmful effects of manganese-containing drinking water have not been reported. The elements are considered to be the least toxic to humans. Its absorption in the body is directly linked to the absorption of iron. High concentrations in the water cause an unpleasant taste. Manganese causes fabric stains in washing machines and weaving machines. It facilitates the growth of microorganisms in the networks resulting in increased cloudiness, odor and deposition.
Copper (Copper – Cu)
It is a key element in human metabolism. Copper salts are toxic to aquatic plants and are used (mainly copper sulfate) to inhibit algal growth. Due to corrosion of copper pipes, significant amounts of copper are dissolved in drinking water. If the water remains stationary for 12 hours in the pipes, the copper concentration may exceed 20 m / g. For this reason, the Sanitary Regulation states two indicative levels: at the exit of the plant and after a 12-hour rest in the pipes. Copper gives color and astringent taste to drinking water. It creates stains on fabrics and sanitary ware. There is no evidence that it causes damage to health.
Zinc (Zinc – Zn)
It is an important element for humans and animals. Sources of zinc in the water
is the corrosion of galvanized pipes and the waste of mines and pellets. Concentrations greater than 5 m / g give color and astringent taste to drinking water. No adverse health effects have been observed.
Phosphorus (P)
All phosphorus compounds occur in the water either dissolved, either as particles or in the body of aquatic organisms. Phosphorus, like nitrogen, is a key element in the growth of algae, and its water content is a determining factor in the eutrophication of surface water. Most of the inorganic phosphorus is due to human waste water and comes from the breakdown of proteins during metabolism. It is also found in many detergents and phosphate fertilizers. Minor amounts of phosphate
they enter the networks from water treatment, where they are used to prevent corrosion in pipelines and boilers. No health effects reported.
Fluoride (F)
Fluoride is found in the waters as fluorinated salts, derived from volcanic rocks. It is usually found in groundwater rather than surface water. It is not elemental in nature because it is very active. It is a key element for man. Research and epidemiological studies have found that fluoride in small amounts in water (up to 1 mg / l) is beneficial because it prevents tooth decay, while at higher concentrations it causes decay (black spots on tooth enamel) or even damage to the bones. It is used in the production of aluminum, steel and glass industries, fertilizers and ceramics. Fluorine-free water is fluorinated by the addition of fluoride and fluorosilicate compounds. In such cases, the fluoride content of the water must be checked frequently so that it does not exceed the permissible limit.
Residual Chlorine
Residual chlorine should be measured in chlorinated waters. Our price
indicates whether the chlorination is sufficient. During chlorination, sufficient amount of chlorine is added to the water to destroy the pathogenic germs and to remain free chlorine so as not to contaminate the water in the pipes. Chlorine gives the water a slight odor and distorts its taste. The small amounts of chlorine present in drinking water disappear with the gastric fluid and are therefore harmless to humans. Large amounts of chlorine cause irritation of the mouth and throat. Chlorination of water must be done properly and monitored regularly so that only small amounts of chlorine reach consumers.
D. PARAMETERS CONCERNING TOXIC SUBSTANCES
Arsenic (As)
Most natural waters contain arsenic at concentrations above 5 µg / l.
It reaches the recipients from the mines, as it is present in almost all sulfur minerals, from pesticides and combustion of fossil fuels. The natural sources of arsenic in the environment are the volcanic activities and the decomposition of plant organic matter. It is toxic and possibly carcinogenic. The toxicity of arsenic depends on its chemical and physical form, dose, exposure time and the way it is introduced into the human body. Causes damage to the gastric, nervous and respiratory system and various skin lesions. Doses between 70 and 180 mg As are fatal.
Cadmium (Cadmium – Cd)
It is one of the most toxic metals. It occurs in nature in sulphurous minerals with
lead and zinc. In natural waters it is found mainly in sediment of the seabed and in floating particles. In unpolluted water the cadmium concentration is below 1 µg / l. Sources of cadmium in water are industrial waste and corrosion of galvanized pipes. In water systems, which are supplied with soft low-pH water, high cadmium concentrations can be found because these waters are more corrosive and the solubility of cadmium in water depends on pH and hardness. Cadmium affects the liver, kidneys, spleen and thyroid gland, is deposited in the bones, where it replaces calcium causing ITAI-ITAI disease. It has been found to cause cancer in experimental animals and some epidemiological studies have linked it to human cancer.
Chromium (Chromium – Cr)
It exists in the earth’s crust and appears as trivalent and weak chromium. In the water they are mainly salts of hexavalent chromium because they are soluble, while they rarely exist as trivalent, because their compounds are insoluble and precipitate. In the atmosphere it is in the aerosol and drained by the rain or deposited on the ground polluting the surface water. The mean concentration in rain water is 0.2 – 1 µg / l, in the sea 0.05 0.05 / l and in natural waters 0.5 – 2 µg / l, while in the basements it is very low. Higher concentrations are due to pollution from industrial waste. It is used in the paint and leather industries, in metal processing plants, in the manufacture of alloys and catalysts. Often, chromates are added to the water to control corrosion. The effects of chromium on health depend on its form. Hexavalent chromium is very toxic. It causes damage to the skin and liver and is considered carcinogenic. Trivalent chromium has not been found to cause health damage.
Lead (Pb)
It is a very toxic metal. Natural waters usually contain up to 5 µg / l lead. Higher concentrations are due to the waste of mines, industries, and the erosion of lead plumbing. Large amounts of lead are present in the atmosphere from the tetraethyl lead added to gasoline as a shock. In most countries unleaded petrol has been abandoned and used. It is also used for the production of batteries, alloys, pigments, anticorrosives. The effects of lead on health were studied many years ago because there were lead poisonings in drinking water resulting from the erosion of lead plumbing. This has led to the abandonment of lead water pipes and the use of lead-based paints for interior decoration. It is a poison with accumulative action. Causes damage to the liver, brain and nervous system.
CONCLUSIONS
Most of the problems in drinking water quality, especially in small communities, are due to fungal infections. Many times though,
serious problems arise from chemical pollution due to natural or human sources. Chemical investigations must be carried out to investigate these cases. However, it would be very costly and time consuming to determine many parameters on an ongoing basis, especially in small populations. For this reason, the parameters recommended for monitoring drinking water quality are those that will determine the health and safety of the water system. The Health Parameter states the following parameters that must be taken into account for controls:
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Minimal Control, E1 includes: Odor, Taste, Conductivity, Residual Chlorine, Microbiological
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Routine Testing, E2 includes: Odor, Flavor, Blurry, Conductivity, pH, Residual Chlorine, Nitrate, Nitrite, Ammonia, Microbiological
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Periodic control, E3 includes: E2 and other parameters.
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Extraordinary E4 inspection is performed in special cases or accidents. The competent authority shall determine the parameters according to the circumstances.
Prior to operating a power source, it is advisable to do so a general analysis (first examination). The parameters to be measured will be those of routine control, to which various toxic or undesirable substances could be added, depending on the source, the type of soil and the pollution from industrial waste.Bibliography
“Standard Methods for the Examination of Water and Wastewater”,
17th Edition, prepared and published by American Public HealthAmerican Water Works Association and Water Pollution Association
Control Federation.
W. Fresenius, K.E. Quentin, W. Schneider (Eds), “Water Analysis”
Springer-Verlag, 1988Degremont, “Water Treatment Handbook” Fifth Edition, 1979, John
Wiley & Sons.C. N. Sawyer & P.L. McCarty: “Chemistry for the Environment
Engineering ”, Third Edition, 1978, McGraw-Hill InternationalEditions (Chemical Engineering Series)
World Health Organization, “Guidelines for Drinking Water Quality”,
Volume 1,2,3 Second Edition, 1993
