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Hygienic standartisation biological factors in environment.
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Hygienic standartisation biological factors in environment.
Such factors in environment are: 1) Pathogenic activators infectious or invasive nature - bacteria, viruses, gelmints, the elementary or it toxins, 2) Allergens biological nature
Main principles standartisation microbe pollution of environment.
1. Absence activators infectious diseases in the certain volumes or amount of object of an environment.
2. Substantiation the allowable contents of microorganisms in objects of an environment at which it are considered safe in the epidemiological attitude.
3. Use at normalization display (sanitary - indicative) microorganisms.
The display-indicative principle of normalization microbes in the environment, offered 100 years more back by R. Koh, and now remains conducting principle of standartisation microbe environmental contamination.
At a choice sanitary - indicative microorganisms as indicators of pathogenic microbes take into account:
1) Commonplace of inhabitation in an organism of the person
2) Identical ways of hit to an environment and organism of the person (way of transfer)
3) Higher survival rate in the environment in comparison with pathogenic microbes, higher stability to disinfecting
4) Harmlessness for the person (inability to cause infectious diseases)
Now as indicator virus pollution of environment use bacteroifags of intestinal stick (E. coli) - coli - fags. It on structure, survival rate, are similar for enteroviruses, causing intestinal infections.
Various sanitary - indicative microorganisms for estimation various objects of an environment were offered, for example, for water of reservoirs - bacteria group of Esherichia coli (BGEC), coli - fags.
The quantitative estimation goes on a coli - index - quantity BGEC in the certain volume of test object and coli - titr - volume of test object in which one BGEC is found out.
For example, for drinking water coli - index - up to 3, coli - titr - more than 300 ml, in sewage coli - index - up to 1000, coli - fags - up to 1000, absence pathogenic microbes in 1 l water. (Tab. 1)
BACTERIAL NORMATIVES IN OBJECTS OF ENVIRONMENT
Tabl. 1
FOR WATER:
| Kind of water | Coli-index | Coli-fag | Absence pathogenic viruses in 1 l of water |
| Drinking | < 3 | - | 10 |
| For bathing | < 1000 | < 1000 in 1 l | 1 |
| Sewage after clearing | < 1000 | < 1000 in 1 l | 1 |
Sanitary estimation microbe air pollution.
Display parameter microbe air pollution of rooms is common microbe number (CMN) - quantity microorganisms in 1 m3 of air, a parameter of direct epidemiological danger - quantity haemolytic streptococcus in 1 m3 of air. Criteria of an estimation bacterial pollution of air of rooms – see tab. 2.
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Special requirements to microbe air pollution are showed in operational, maternity halls for preventive intrahospital infections, postoperative complications (see tab. 3).
Tabl. 2
FOR ESTIMATION AIR OF PREMICES:
| Quality of air | Common microbe number in 1 m3 | Amount haemolytical Streptococcus in 1 m3 |
| Clear | < 2000 | < 10 |
| Satisfactory clear | 2000 – 4000 | 11 – 40 |
| Low polluted | 4000 – 7000 | 40 – 120 |
| Polluted | > 7000 | > 120 |
Tabl. 3
FOR ESTIMATION AIR OF OPERATIONAL:
| Time of definition | Common microbe number in 1 m3 | Amount golden Staphylococcus in 1 m3 |
| Before operation | < 500 | 0 |
| During operation | < 1000 | < 4 |
For the estimation bacterial pollution of ground used Coli-titr, titr Cl. Perfringens, amount eggs of helmints in 1 kg.
FEATURES OF HYGIENIC REGLAMENTATION HARMFUL FACTORS IN VARIOUS OBJECTS OF ENVIRONMENT
Hygienic standartisation pollutants in atmospheric air.
Pollution atmospheric air represents the greatest health hazard for the person among other objects of an environment for the following reasons:
1) The majority of emissions harmful substances acts in air and is carried on the big distances - plenty of the population is exposed to its influence
2) At inhalation way of receipt the big surface of lungs, penetrated capillaries is exposed to influence - in blood quickly create high concentration pollutant and blood from lungs pass a liver and is carried on an organism, causing poisonings
3) Except for direct negative action on organism of the person, atmospheric pollution renders indirect negative effects on health and conditions of life of the population.
Kinds of hygienic specifications in atmospheric air.
Atmosphere pollutants by influence on an organism share on 3 groups:
1) Substances of the reflex (irritating) action
2) Substances of the absorbtion (toxic) action
3) Substances of the reflex - absorbtion action
2 kinds maximal permissible concentration for atmospheric air:
1) Maximal – single permissible concentration (MPC m. s. ) - are designed for 20-30 minutes influence of irritation pollutants and are directed to prevention reflex reactions and poisonings in people at high concentration pollutants in air (emergencies). Are established on irritating action on mucous of eye and toxic influence. For toxic substances such researches will be carried out on animals with carry of the data for the person.
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2) Daily average maximal permissible concentration (MPC d. a. ) are designed for absence pathological changes at people at round-the-clock influence during all life, and also for absence the remote effects in the subsequent generations. MPC d. a. below MPC m. s. in view of the greater exposition (time) of influence.
Criteria harmful action at standartisation pollutants in atmospheric air:
1) organoleptic (threshold concentration of pollutant on change odour, colouring, transparence of air)
2) Reflex (threshold concentration on irritation - olfactive influence on the man or laboratory animal)
3) Toxicological (threshold on common toxic, specific or remote effects at inhalation action at laboratory animal)
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