Māris kļaviņŠ, azamat azizov, JĀnis zaļoksnis environment, pollution, development: the case of uzbekistan

Figure 8.13. 
Structure of 
micelle

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8. WATER POLLUTION
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Water softener additives in detergents are needed to reduce the 
adverse effects of water hardness. These substances bind calcium and 
magnesium ions in stable complexes. The water softeners used most 
often are polyphosphates, sodium tripolyphosphate (Na
3
H
2
P
3
O
10
), 
sodium silicate or organic substances. These substances cause water 
eutrophication. 
The  compound  which  often  has  a  significant  impact  on  water 
quality  is  hydrogen  sulfide  H
2
S.  Hydrogen  sulfide  is  formed  in 
anaerobic environ ment, it is easily soluble and one of the few 
compounds whose amount in water is regulated by the water quality 
standards. Although hydrogen sulfide is toxic, its presence is felt at 
significantly lower concentrations than those, which, when reached, 
begin to cause the toxic effects of hydrogen sulfides.
In general, substances that adversely affect the taste and odour 
of drinking water are not regulated by any standards. There are 
several reasons for this. In general, substances which impair taste 
and smell of water are contained in water in microscopic quantities, 
and their effect is not toxic. 
Water can be contaminated due to the presence of increased 
amounts of many metals and microelements. Pollutants with a