Organoleptic indicators of drinking water quality

• What indicators are called organoleptic?
• Methods and assessment of organoleptic indicators of water
• What substances in water affect organoleptic characteristics?
• Hach Solutions

What indicators are called organoleptic?

Organoleptic refers to those qualities of water that affect the senses. The organoleptic indicators of water quality include: color, turbidity, transparency, smell and taste. Water that is absolutely pure from a chemical point of view does not have these qualities, since it has no smell and taste, however, such water does not occur in nature and is not used for drinking. Requirements for organoleptic indicators of water are established by goverment regulations.

Methods of analysis and evaluation of organoleptic indicators

Turbidity

Occurs due to the presence of suspended solids in the water (particles with a diameter of more than 100 microns). Turbidity is measured by weight or non-phylometric methods, expressed in mg/l or turbidity units (FMU, NTU, FNU, etc.). The main reason for the need for turbidity control is the decrease in the effectiveness of water disinfection with ultraviolet light and the development of microorganisms due to the presence of suspended solids.

Turbidity is determined using turbidity meters. The principle of operation of these devices is based on the determination of light scattering in a disperse medium. The standard for turbidity of drinking water is 2.6 turbidity units for formazin or 1.5 mg/l for koalin. The method for measuring turbidity is established in appropriate standards.

Color

It characterizes the intensity of water color. It is determined on the platinum-cobalt scale and expressed in degrees. One degree of color corresponds to the content in 1 liter of a solution of 2.49 mg of potassium chloroplatinate (K2[PtCl6]) and 2.018 mg of cobalt chloride CoCl2▪6H2O;

For color the established limit is no more than 30 degrees. Color is determined using colorimeters or spectrophotometers.

Smell and taste

These indicators are present due to dissolved salts, gases, organic compounds formed during the life of aquatic organisms. The main causes of taste and smell in water are:

• rotting plants;
• fungi and mold;
• glandular and sulfurous bacteria;
• heavy metal compounds;
• salts of alkali and alkaline earth metals;
• industrial waste;
• water chlorination.

Unlike turbidity and color, these indicators cannot be accurately measured and are evaluated by an expert method using a special scale.

What substances in water affect organoleptic characteristics?

Turbidity is affected by all substances insoluble in water.

For color - all colored, such can be metal compounds or some organic substances.

Taste and smell - these indicators in water can provoke various organic and inorganic compounds. Among which are: ammonia / ammonium ion, hydrogen sulfide (putrefactive, rotten), alcohols, wood resins, magnesium salts (bitterness), sulfates (bitterness), chlorides (salty).

Hach Solutions

Hach provides a wide range of high-quality equipment that provides the most accurate water analysis.

AquaAnalytics®💧is the official representative of Hach in Russia and CIS countries. Contact us and our specialists will select the necessary instruments and reagents for water quality analysis.

Representative office in Russia: +7 (495) 201-53-02 info@aquaanalytics.ru

Representative office in Uzbekistan: +998 (90) 174-57-84 info@aquaanalytics-tekhnika.ru