We investigated the immune status in 1828 persons which had been exposed at work to harmful factors: 1174 of biological origin (1122 at producing protein-vitamin concentrates - PVC, 52 at producing hydrolysis yeast - HY), 543 - of chemical origin (311 had to do with respiration-irritant gases - RIG: chlorine, phosgene, sulphur dioxide, ammonia; 118 - with toluylene diisocyanate - TDI, 114 - with acryl compounds - AC), and 111 - of physical origin (local vibration - LV); moreover, 60 persons were examined that had no industrial contact with harmful factors (control group). A complex of immunology investigations was used: counting of T-Lymphocytes (T-L), high avid T-Lymphocytes (HAT-L), B-Lymphocytes (B-L), load tests with theophylline and levamisole with distinction of theophylline-resistant, theophylline-sensitive, and levamisole-reactive lymphocytes (ThR-L, ThS-L, LR-L), concentration of blood serum immunoglobulins - IgM, IgG, IgA; absorptive ability (phagocyte number - PhN) and metabolic activity of neutrophiles in spontaneous and stimulated NST-test; saliva immunity was evaluated by the level of IgM, IgG, IgA, secretion IgA (sIgA), lysozyme with calculation of balance coefficient (BC) of these factors; allergic reactivity - by the level of blood eosinophiles and basophiles, general IgE, basophiles degranulation test (BDT) and specific rosettforming reaction (SRR) [1, 2, 3]. Results evaluation was carried out with application of created model on the base of mathematical statistics and algorithm theory methods [4].

The investigation lets conclude that influence of industrial factors of biological, chemical, and physical origin results in forming the alternations of the immunity system. Their direction and profoundness depended on the kind of an influencing factor, on its strength, duration, and the basal state of the organism.

Under the influence of products of microbiologic protein synthesis, the following changes were revealed: a suppression of cellular immunity which is more explicit in persons contacting with HY (functional alternations of T-cells in this case are mainly connected with reversible masking of E-receptors); variously directed alternations of humoral immunity - depression in persons exposed to influence of PVC, and activation with influence of HY; oppression of neutrophile phagocytosis function; saliva immunity misbalance increased by HY; signs of sensibilization against production components, as for PVC - also allergization in comparison with the control [2].

Under influence of chemical compounds, the following was revealed: a less depression of a cellular link, which was accompanied by functional alternations of T-Lymphocytes in persons contacting mainly with TDI; humoral immunity suppression, more explicit while contacting with RIG, with simultaneous hyperproduction of IgA; inhibition of phagocyte and metabolic neutrophiles activity; increasing misbalance of local immunity and signs of organism allergization [3].

Under conditions of local vibration influence, with modification changes of T-cells which are eliminated by levamisole, the following was revealed: a depression of cellular immunity, inhibition of humoral link, oppression of neutrophilic phagocyte and metabolic activity; disbalance of saliva factors [1].

Comparing evaluation of immunity status in workers of various industry branches showed that depression of cellular immunity was detected in persons exposed to the biologic and the physical factor, while disturbance of functional activity of T-cells took place when influenced by both factors (decreasing of HAT-L while contacting with the physical, decreasing of TR-L while contacting with the biologic), and reversible modification changes of T-cells were detected only under influence of the physical (increasing of LR-L). Suppression of humoral immunity was mostly explicit in workers exposed to the physical factor - decreasing of IgM, IgG, IgA in blood serum and decreasing of B-L were detected, while in workers of PVC and HY factories only decreasing of B-L took place. Inhibition of neutrophilic phagocyte activity was revealed while contacting with the physical factor, greater disbalance of local immunity while dealing with chemical substances, the highest sensibilization level in persons contacting with biologic factor.
The analysis of immunological data depending on duration of work under conditions of harmful production factors influence revealed that under influence of biologic factor the highest level of sensibilization against PVC took place during first 10 working years: the peak of reagin and cellular reaction took place after 1-4 working years; also, decreasing of TS-L, B-L and increasing of IgA concentration was revealed. In persons working more than 10 years, the level of sensibilization against PVC products notably decreased, while depression of cellular immunity parameters came to being (on the background of increasing synthesis of IgM and IgG) and forming of more explicit saliva immunity disbalance. Among workers exposed to chemical factors the prevailing majority of changes were noticed after 10 working years: decreasing of T-cells and their functional activity, parameters of humoral immunity, disbalance of saliva factors. In workers contacting with the physical factor the greatest changes of immunity homeostasis took place after 10 working years till 20 working years and found their expression in depression of cellular immunity: decreasing of T-L and HAT-L, humoral immunity, misbalance of local immunity.

Clearing up the explicitness of immunological distortions depending on nosological form of pathology developed in workers exposed to influence of harmful production factors, some regularity was revealed. In persons contacting at work with the biologic factor respiratory allergosis was characterised by increasing of blood eosinophiles and BDT intensity, decreasing of HAT-L and TR-L. Development of chronic bronchitis in chemical industry workers was accompanied by decreasing of T-L, TR-L, IgM, IgG and neutrophilic phagocyte activity. With the vibration disease in persons contacting with local vibration, decreasing of T-L, HAT-L, TS-L, IgM, IgG, IgA, PN and saliva immunity disbalance.

Figure 1

The generalised immune parameter (GIP) was calculated on the base of a great list of immunological investigations; moreover, selection of diagnostically relevant data was carried out for determining a pathologic state in workers dealing with harmful production factors. A significant GIP excess during development of allergosis in persons contacting with PVC, during chronic bronchitis in workers of chemical factories and during vibration disease in persons working under conditions of vibration is revealed in comparison with healthy people. The limit GIP numbers were calculated for some forms of detected pathology, which are mostly probable prognostic criteria, exceeding of which is a base for considering the investigated persons to belong to the risk group of the pathology development.

The obtained results of immune status evaluation concerning workers of various industry branches witness an unfavourable influence of the biologic, chemical, and physical factor on the organism being in contact with it. First of all, influence of mentioned factors causes development of a certain pathology in a certain group of people. The occupational origin of this is proved. Further, the investigations revealed mainly a suppressive effect on the cellular immunity system which is mostly explicit under conditions of biologic factor influence; on humoral immunity system and neutrophilic functions increasing under physical factor influence; also, misbalance of local immunity protective qualities under chemical factor influence and high sensibilization level under influence of the biologic one.

It is to be stressed that with each form of pathology detected in workers exposed to various production factors there was a depression of cellular immunity parameters, and inhibition of humoral immunity and neutrophyles functions - under influence of the chemical and physical factor. Mostly unfavourable is a long-lasting production contact within 10 - 20 years, particularly, in contact with vibration the immune status alterations are gradually smoothed and vanish, which may be caused by development of compensatory-adaptive reaction. Out of the rule is forming of sensibilization to the products in workers of microbiologic industry, the maximum of which is registered during first 1-4 working years; later, decreasing of its intensity follows.
In concern with the above mentioned, for prophylactics of explicit pathology forms and harmful influence of industrial factors, early diagnosis of the influence and its prognosis is gaining great importance. The realisation is possible with the help of generalised immune parameter whose role is to determine risk groups among workers for carrying out treatment and prophylactics.

1. Egorova IV, Litovskaya AV. Med Truda Prom Ekol 1998;(4): 13-7.
2. Litovskaya AV, Egorova IV Immunologia, 1996 (deposited in Russian State Scientific Medical Library March 19, 1996, ¹ D25059).
3. Litovskaya AV, Egorova IV Immunologia, 1996 (deposited in Russian State Scientific Medical Library March 19, 1996, ¹ D25060).
4. Litovskaya AV, Sadovsky VV, Vifleemsky AB Med Truda Prom Ekol 1995; (9): 30-3.
5. Petrov RV, Khaitov RM, Pinegin BV Immunologia 1995;(2):4-5.