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Toxicological characteristic main groups pesticides
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TOXICOLOGICAL CHARACTERISTIC MAIN GROUPS PESTICIDES
1. Chlorine- organic (CHOP). Mechanism insecticide and toxic action - blockade respiratory enzymes in tissues, it is especial cytochromoxidaze (display enzyme for diagnostics poisoning). Clinic of poisoning: defeat CNS, liver, kidneys, endocryne systems, mutagen, cancerogenic action.
Ecological danger - very much stable in biosphere, therefore practically all are forbidden to application. According to Washington Academy of Sciences, half-life period of DDT in biosphere - some centuries.
2. Phosporos-organic (PHOP). Mechanism action – blockade enzyme cholinesteraze in blood. Cholinesterase need for destruction acetylcholine, when it is inactivated - accumulation acetylcholine in cynapses. 2 stages of poisoning - excitation, then oppression and destruction vital centers CNS. Clinic - overexcitation choline-reactive systems. Poisonings because of small stability PHOP in the environment (1-3 months) are more often sharp. Last years for PHOP is found out remote neurotoxity - defeats of peripheral nervous system and CNS after years after poisoning (functional cumulation). Prospects of the further application are insignificant because of big toxicity and accustoming of wreckers (the oldest group of pesticides).
3. Carbamates. (The salts of carbaminic acids). Now it group frequently offered by chemical firms. The mechanism of action is like PHOP, but blockade of cholinesterase is convertible and through time its activity is restored, therefore poisonings less heavy, than at action of PHOP. Rather stable in biosphere (about one year and more), for some preparations are established the remote effects (in experiment).
4. Mercury and arsenic organic pesticides. Mechanism of action - blockade tiolov enzymes (contain SH-group. ), are extremely toxic. Are applied as fungicides at grain.
5. Preparations of copper. It is old preparations, are applied on vineyards, including in Crimea. Has low toxity - in intestines formed copper albuminates - is not absorbtion in the blood, has irritating action in intestines. Poisonings are usually easy or average degree. Treatment is washing stomach, application antidotes of heavy metals - pectins, unitiol.
6. Symmetric triasines. It is widely applied as herbicides in rice checks in Crimea and with waste waters pollute coastal sea water areas. Basically is low toxic. Has high stability in biosphere. It is revealed cytotoxic action - influence at structure nuclein acids.
7. Synthetic pyretroides - rather new group with sharp selectivity for insects. Are synthesized on the basis of natural pyretrins (flowers of Dalmat camomiles in the beginning of 20 th century were applied as insecticides). It is low toxic for the person and also are unstable in the environment, the mechanism of action not good studied, there are separate messages about the remote effects. Perspective group, but rather expensive preparations.
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HYGIENE of WORK WITH PESTICIDES
Because it is very toxic group of agrochemicals, there are very strong demands to conditions of work and contact with these substances.
Hygiene of work at storage pesticides.
The territory of warehouse for pesticides should be protected from access of other persons, must be removed from living houses and other objects on 200-1000m (depending on toxicity of stored preparations – if there is extremely toxic group of pesticides – 1 km). On territory must be platforms for washing motor transport and mechanisms from the rests of pesticides, measures for prevention drains in environmental places. An internal covering of a warehouse must be from not adsorbing materials, preparations should be stored in tight container, good ventilation, must be premises for stay of the personnel, storage clothes, souls. It is necessary constant current sanitary control levels pesticide pollution air, hands, overalls of the personnel, tightness of packing preparations, rules of work with toxic substances.
Hygiene of work at transportation pesticides.
Common rules of transportation chemically dangerous cargoes: special transport, the routes specially chosen by sanitary service – far off towns, hospitals, sanatoria, etc. In the car must be means of individual defence and desintoxication pesticides in case of failure.
Hygiene of work at application pesticides.
Because many pesticides are highly toxic substances, at work with them - strict safety requirements:
- Restriction of work time - 4 hours (pesticides 2-3 class of danger) or 2 hours (1 class of danger);
- Observance term of renewal works (after processing plants), in hothouses it is very small - 1-3 days;
- Observance term of expectation - the period between processing and harvesting (depends on toxicity, stability of preparation, culture of plants), for example, for PHOP on apple trees - 20 days;
- Preliminary and current physical examinations, early revealing and treatment pesticide poisonings (in special clinics);
- Preventive and current sanitary control at application pesticides;
- Use individual means of protection bodies of breath and skin;
- Observance rules of personal hygiene - bath after work, feed in special places.
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