Modern medicine believes that the complete concept of healthy water should have the following 7 standards:
① Does not contain substances that are toxic, harmful and odorous to the human body;
②The hardness of water is moderate;
③ The minerals required by the human body are moderate;
④The acidity and alkalinity of water are neutral or weakly alkaline;
⑤ Dissolved oxygen and carbon dioxide in water are moderate;
⑥ The water molecules are small, and the vitality of water is high, which is easy to be absorbed and utilized by human cells;
⑦ Water has strong nutritional and physiological functions such as osmotic pressure,solubility,and metabolism.
We have to drink water every day.If we drink water that does not meet the hygienic requirements,it will do great harm to our body.So,how to judge the quality of drinking water?
Generally,there are the following three requirements:
1.Observe the sensory properties of water quality
Generally,the characteristics of water quality that can be detected by human eyes,nose,tongue and other sensory organs,such as water color,smell,taste,transparency and turbidity.Clean drinking water with good sensory properties,water quality without any color,clear and transparent,free from sediment,debris and visible organisms.If there is abnormal color,odor and turbidity,the water quality is often affected by pollution and adverse factors,and the water is not drinkable.
2.No chemicals
Good drinking water contains appropriate amounts of trace elements such as iron,iodine,copper,etc,which are required by the human body,but cannot contain cyanide,arsenic, mercury,cadmium,organophosphorus pesticides,etc,which are toxic and harmful to the human body,or the content is very small,which is not harmful to the human body. threatening.
3.Does not contain microorganisms such as pathogenic bacteria and viruses
Generally speaking,the total number of bacteria per milliliter of water should not exceed 100,and the number of Escherichia coli should not exceed 3 per 1000 milliliters of water.Such water can be considered as drinking water that meets sanitary standards.
