Review Article

Occupational respiratory diseases in hungary – some experiences in the last 40 Years

András Mándi

National Institute of Occupational Health, Budapest, Hungary

Corresponding author:

Professor Dr. András Mándi

National Institute of Occupational Health

Budapest, POB 22, Hungary H-1450

Phone: (361) 215-7890

Fax: (361) 215-6891

CEJOEM 1996, 2:309-316

Abstract: Abstract: 40 years’ Hungarian experiences with the most important occupational respiratory diseases: silicosis, asbestosis, lung cancer, extrinsic allergic alveolitis, occupational asthma and industrial bronchitis are reviewed. The trends and changes of incidence, diagnostic methods, clinical manifestations are discussed.

Key words: Silicosis, asbestosis, lung cancer, extrinsic allergic alveolitis, occupational asthma, industrial bronchitis, lung functions

Abbrevations:
Co: cobalt
CT: computertomography
FEV1: forced expiratory volume in one second
IgE: immunglobulin E
ILO: International Labour Office
MDI: methyl-diisocyanate
Raw:airways resistance
TDI: toluene-diisocyanate
VC: vitalcapacity.

Introduction

Professor Imre Pacséri MD, PhD (1900–1980) organized the first polyclinic for occupational diseases in Budapest in the early ’30s as a department of the National Insurance Company. This polyclinic developed into the National Institute of Occupational Health in the ’50s and it has been working as a central institute of the Ministry of Health and Welfare since that time.

In my memorial lecture remembering on Professor Pacséri I would like to present a short overview on the evolution, changes and trends of the incidence, diagnostic methods and clinical manifestations of the most important occupational respiratory diseases in the last 40 years in Hungary.

Silicosis

As we have recently published in this Journal ( Mándi et al. 1995) the incidence of silicosis decreased during this period from 800–900 cases per annum to 20–30 new cases and parallel with this drop the severity of radiological findings in newly diagnosed cases diminished. At the beginning of our diagnostic work in the ’50-s only an X-ray film was taken on each patient for screening purposes applying the ILO Pneumoconiosis Classification ( ILO 1958).

Detailed medical investigations, lung function measurements including spirometry, lung mechanics – lung compliance, later measurement of airways resistance by body pletysmography, flow-volume curves – and blood gas analysis were introduced in the ’60-s. Our studies, in good agreement with the data of British and German authors (Cochrane 1973, Ulmer et al. 1968), proved the following: in cross-sectional studies respiratory complaints characteristic to chronic simple bronchitis – chronic cough and expectoration – were significantly more frequent among silica dust exposed persons than in non exposed persons (Table 1), but the mean values of the airways resistance (Raw) of these groups were statistically equal (Table 2) i.e. while occupational silica dust exposure itself caused an increased rate of simple chronic bronchitis, it didn’t induce general airway obstruction characterized by elevated airways resistance. In another cross sectional study comparing the airways resistance values of silica dust exposed persons grouped according to their radiological grades of silicosis we observed a significant elevation of this parameter only in the most severe group with B–C grade of silicosis (Table 3) (Mándi et al. 1972).

**Table 1. Frequency of cardiorespiratory complaints and the proportion of complaints indicating chronic bronchitis (regular cough and expectoration) in dust exposed and control persons**
	Non dust exposed (n=123)	Dust exposed (n=377)
Free of complaints	73.1%	53.5%
Cardiorespiratory complaints	26.9%	46.5%
From these bronchitic complaints	9.8%	20.9%

**Table 2. Mean airways resistance values of dust exposed and control persons**
	Non exposed (n=123)	Dust exposed (n=377)
Mean Raw (cmH2O/l/s)	2.17	2.22 *
±SD	1.26	1.16
*: p > 0.05

**Table 3. Mean airways resistance values (Raw) in different radiological grades of silicosis**
**(Radiological grade)**
	SiO	p	q	r	A	B–C
n	549	172	58	32	66	29
Mean Raw (cmH2O/l/s)	3.27	3.07	3.20	2.97	3.43	5.42
±SD	2.13	2.46	1.79	1.60	1.70	3.00
p < 0.05

The airways obstruction has a significant effect on the surviving prognosis of the dust exposed persons with chronic bronchitis: in our first 10-years follow-up study (Mándi and Galgóczy 1972) we found that the starting FEV1/VC values of dust exposed persons were significantly higher in survivors than among patients dying of respiratory illness during the observation period (Table 4). In our second follow-up study (Table 5) the same surviving rate of dust exposed persons with and without silicosis was found with the exception of the most severe radiological (B–C) group at the start, in which the bad prognosis was determined by the massive fibrosis and the airways obstruction, respectively (Mándi et al. 1984).

Table 4. Relationship between the FEV1/VC value and a 10-year survival time of patients with chronic bronchitis ( n = 138 )
Survived
n=115
(83%) Died in 10 years
n=23
(17%)

Mean FEV1/VC at the start
of the studies (%) 71.8 65.8

±SD 11.5 11.8

p<0.05

Table 5. Relationship between the starting radiological grade of silicosis and 10 years of survival
(Radiological grade)
SiO p q r A B–C

Alive n
% 174.3
181.3 65.3
80.2 25.3
86.2 18.3
72.7 27.3
78.8 14.3
33.3

Died of other disease n
% 35.3
16.4 11.3
13.6 2.3
6.9 13.3
27.3 15.3
15.1 0
0

Died of respiratory insufficiency n
% 5.3
2.3 5.3
6.2 2.3
6.9 0
0 2.3
6.1 18.3
66.7

p<0.05

Our above mentioned results contributed to the elaboration of Hungarian measures concerning silicosis. As it was mentioned in our previous article the sharply decreased incidence due to prevention and early diagnosis meets the requirements of “The eradication of the silicosis by 2000” WHO program.

Asbestosis

The screening of the asbestos exposed persons was started in the early ’60-s in an asbestos textile factory, later in the asbestos cement industry, among insulation workers, construction workers and among mechanics working with brakes containing asbestos, but the screening has never covered the whole asbestos exposed population. The incidence rate of asbestosis is relatively constant: between 15–30 cases per annum. The most severe asbestos fibroses and lung cancers were found among the asbestos textile workers. Now the production of asbestos textile as well as the use of crocidolite asbestos is banned in Hungary. In the early diagnosis of asbestos caused pleural and lung diseases computertomography has been playing an increasing role although correct indications considering the cost versus benefit ratios, graduation of the findings and comparison between the CT and ILO classification is still lacking (Posgay et al. 1995).

Lung cancer

Since 1983 lung cancer of uranium miners depending on their former WLM (working level of month) exposure has been a compensated occupational disease in Hungary. The incidence rate is between 5 and 25.

Lung cancer and mesothelioma of patients with proven occupational asbestos exposure even in cases without a previously diagnosed asbestos fibrosis have been accepted as compensated occupational diseases since 1993.

Although cancerogenity of silica dust is generally more and more accepted we haven’t observed this effect in our silicotic patients, neither Kádas could detect a higher lung cancer incidence among coal workers of the coal mines in Pécs, southern Hungary (Kádas 1996).

Organic dust

The two main types of occupational respiratory diseases caused by organic dusts are extrinsic allergic alveolitis and occupational asthma.

Among the etiologic factors of extrinsic allergic alveolitis thermophilic actinomycetes play the most important role causing an inflammatory process characterized by fever, leucocytosis, lung infiltration, cough, dyspnoea and crepitation over the lung. The first cases published in Hungary were those of paprika splitters and mill workers in the early ’30s, the most frequently observed form in the last years is mushroom worker’s lung (Csepura et al. 1995).

Occupational asthma

Among the definitions of occupational asthma we prefer the definition of Brooks: “occupational asthma is a respiratory disorder characterized by reversible obstruction of airways and caused by the inhalation of substances or materials which are manufactured or directly used by a worker or are incidentally present at the work site.” (Brooks 1977).

The real incidence of occupational asthma in Hungary is not known. While in the majority of highly developed countries occupational asthma is the most frequent occupational respiratory disease of the 90s the number of registered cases in Hungary had been a one figure number which only in 1995 outnumbered 10 with the 17 new cases. This misleadingly low number can be explained by the fact that although occupational asthma is a registerable disease in Hungary, it is not eligible for compensation. In consequence patients are not interested in the registration from a financial viewpoint. The asthma register in Hungary, therefore, seriously underrecords the true incidence of the disease and is not at all comparable with that in other countries.

In the diagnosis of occupational asthma we apply the internationally recommended criteria (Sterk et al. 1993).

Obligatory criteria

The patient’s history must include the exact working history, detailed information about all the materials to which there is exposure and about the irritative or sensitizing potential of these materials. Also, a precise description of the clinical symptoms is needed. In particular, it is necessary to define how symptoms relate to the working situation and the time of onset of dyspnoea in relation to exposure: is it an immediate or a late reaction? Does the occurrence of dyspnoe depend on the presence of some suspected working material or on a new material, etc.?

A specific bronchial challenge test is the gold standard for the diagnosis. Tests of this kind generally involve inhalation exposure of the suspected workplace material(s) to see if such an exposure provokes bronchoconstriction. Great caution is needed in the application of such tests.

Additional data

A procedure widely followed in some countries is to monitor the PEF at home and at work. However in our opinion the reliability of this procedure is much less than that of challenge tests.

Skin tests (prick tests) using standard non-occupational and occupational solutions are also widely used. Such tests have proven their value in the detection of sensitization but not in the diagnosis of asthma.

The detection of specific IgEs has diagnostic value in some cases.

The non-specific airway responsiveness can be determined by histamine or metacholine challenge. The reaction is positive if there is a decrease in the FEV1 value by 20% or more after the inhalation of small concentrations or doses of histamine or metacholine (PC20 or PD20: provocative concentration or provocative dose, respectively).

The main causes of occupational asthma in Hungary are similar to those in other countries. (Table 6)

**Table 6. Main causes of occupational asthma in Hungary**
High-molecular-weight compounds	Low-molecular weight compounds
Laboratory animals (e.g. rats and mice) Flour (e.g. wheat and rye) Textiles (e.g. cotton) Pollens Algae Biological enzymes (e.g. papain, pancreatin, amylase) Herbs (e.g. soap root Saponaria officinalis L.)	Di-isocyanates (TDI,MDI) Anhydrides (phtalic) Metals (Co) Drugs (e.g. a-methyl-dopa, hexachlorophene) Resins (e.g. colophony, epoxy, phenol- formaldehyde) Formaldehyde

Industrial bronchitis

Chronic bronchitis as an occupational or work related disease might be diagnosed only on the basis of epidemiological studies, because chronic simple and obstructive bronchitides are polyetiological diseases. Despite the difficulties there are exposures and occupations in which the incidence and prevalence of chronic obstructive bronchitis are higher than in non exposed persons of the same age and smoking habits. In the ’70s we found significantly increased mean airways resistance value and increased frequency of elevated resistance values in aluminum foundry workers compared to those of iron casting workers (Table 7), and this elevated frequency had a good correlation with exposure time (Table 8). This could be explained by the high concentration of fluorides, sulfur dioxide and carbon monoxide at the workplace in consequence of the technology used (Mándi et al. 1975).

**Table 7. Mean airways resistance values of iron casting and aluminium foundry workers**
	Iron casting (n=377)	Aluminium foundry (n=153)
Mean Raw (cmH2O/l/s)	2.22	2.78
±SD	1.16	1.71
p < 0.05

**Table 8. Relationship between the length of work history and the frequency of pathologic airways resistance values in iron casting and aluminium foundry workers**
	Exposure time (years)	Frequency of increased Raw values (%)
	Iron casting (n=377)	Aluminium foundry (n=153)
<5	6.1	12.5
66–10	11.5	7.1
11–15	11.0	20.0
15<	8.8	31.5

For the future the research of allergic occupational lung diseases, occupational cancers, occupational bronchitis, research of new methods for the early diagnosis and the preservation of the results achieved on the field of pneumoconioses seem to have a great importance.

REFERENCES

BROOKS, S. M. (1977). “Bronchial asthma of Occupational Origin.” Scand. J. Work. Environ. Health 3:53–72.

CSEPURA, O., ANDRÁSSY, K. and SZÉKELY, K. (1995). (In Hungarian) “Mass allergic respiratory disease in mushroom workers.” Egészségtudomány 39:181–183.

COCHRANE, A. L. (1973). “Relation between radiographic categories of coalworkers’ pneumoconiosis and expectation of life.” Brit. Med. J. II:532–534.

ILO (1958). “Meeting of experts on the international classification of radiographs of the pneumoconioses.” ILO, Geneva, 1958.

KÁDAS, I. (1996). “Simultaneous Occurrence of Silicosis and Lung Cancer. Coincidental or Associated?” Cent. Eur. J. Occup. Environ. Med. 2:37–46.

MÁNDI, A. and GALGÓCZY G. (1971). (In German) “Follow-up study of dust exposed persons with chronic bronchitis.” Pneumonologie 144:315–322.

MÁNDI, A., GALGÓCZY, G., CSUKÁS, M., VILLÁNYI, GY. and MÁGA R. (1972). (in German) “Relationship between clinical symptoms, smoking habits and lung functions in dust exposed persons.” Int. Arch. Arbeitsmed. 30:245–71.

MÁNDI, A., GALGÓCZY, G., GALAMBOS, É., HORVÁTH, F. and CSUKÁS., M. (1975). “The Prevalence of Obstructive Bronchial Diseases among the Workers of Aluminum Electrolysis and Iron Casting Factories. “VIII. Interasma Congress, Vlissingen, pp. 484–499.

MÁNDI, A., GALGÓCZY, G., GALAMBOS, É., NÉMETH, L. and DOMBOS K. (1984). “Changes in Clinical Status and Lung Functions of Patients with Chronic Respiratory Diseases over 10 Years.” Respiration 46:151–159.

MÁNDI, A., Galambos, É. and Galgóczy, G. (1995). “Silicosis in Hungary.” Centr. Eur. J. Occup. Environ. Med. 1:262–5.

POSGAY, M., NÉMETH, L. and MESTER, Á. (1995). “About Classification in High Resolution Computed Tomography of the Chest after Asbestos Exposure.” Centr. Eur. J. Occup. Environ. Med. 1:125–131.

STERK, P. J., FABBRI, L. M., QUANJER, Ph. H., COCKROFT, D. W., O’BYRNE, P. M., ANDERSON, S. D., JUNIPER, E. F. and MALO, J. L. (1993). “Airway Responsiveness: Standardized Challenge Testing with Pharmacological, Physiological and Sensitizing Stimuli in Adults.” Eur. Respir. J. 6 (Suppl. 16):53–83.

ULMER, W. T., REICHEL, G. and WERNER, U. (1968). (In German) “Chronic obstructive Bronchitis of the Coal Miner. An Epidemiological Study of its Incidence in the Normal Population and in Coal Miners. The Importance of Dust and Smoking”. Int. Arch. Gewerbepath. Gewerbehyg. 25:75–98.

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