Occupational cancer in Germany.

As in probably mostly all other European countries, the incidence of occupational cancer in Germany increased steadily after World War II. In 1994 about 1,600 cases of occupational cancer were compensated--more than ever before. More than half of these cases were lung cancer, most caused either by asbestos (n=545) or by ionizing radiation ((italic)n(/italic)=306). Other frequent target organs of asbestos were the pleura and the peritoneum with 495 cases of mesotheliomas. Asbestos was the single most important risk factor for occupational cancer, causing more than 1000 deaths per year. All other malignant diseases, such as bladder cancer, leukemia, angiosarcoma of the liver, adenocarcinoma of the nose or nasal sinuses, and skin cancer, were comparatively rare. Although primary exposure to ionizing radiation in uranium ore mining occurred in the 1950s and attributable lung cancers seem to be on the decline, this is not true for asbestos, where the peak incidence in lung cancer and mesothelioma has not been reached yet. ImagesFigure 2

The most generally accepted estimates of cancers attributable to occupation are those given by Doll and Peto for the United States in 1981 (1). They concluded that about 4% of all cancer deaths may be caused by occupational carcinogens. The percentage is higher for lung cancer (males, 15%; females, 6%) and bladder cancer (males, 10%; females, 5%). These estimates are proportions and therefore dependent on the prevalence of occupational and other carcinogenic risk factors in a population. They cannot readily be transferred from the United States to Germany or any other country. As Boffetta et al. (2) pointed out, in specific populations the proportion of different cancers due to occupational exposures can be much higher. In Germany this is true, for example, for Saxony and Thuringia, where a high proportion of lung cancer in the population is due to prior exposure to a-radiation in underground uranium mining. This is a rare cause of lung cancer in other parts of Germany. Without knowledge of the prevalence of exposure, attributive risk estimates may be misleading. This  An attempt is made to describe the potential exposures present or formerly present in the industries of Germany and the statistics referring to the burden of occupational cancer. Official statistics (3,4) relate to newly diagnosed and compensated occupational diseases, which are only the "tip of the iceberg" of the true total, as many patients fail to obtain compensation because their disease is not recognized as occupational and is not reported to the authorities. Skov et al. (5) showed that the Register of Reported Occupational Diseases of Denmark contained only about 50% of the cases of pleural mesothelioma and sinonasal adenocarcinoma in the Danish Cancer Register. Reporting of all known or suspected occupational diseases to the Labor Inspection Service is compulsory in Denmark, and the same is true for Germany. Therefore, it seems very likely that underreporting is also a problem in Germany. The number of unknown cases will vary according to the disease, or as Skov put it, "If this [underreporting] is the state of affairs with well-known occupational cancers like mesothelioma and sinonasal adenocarcinoma, one wonders about cancers that are not as unequivocally associated with occupational exposures." (5). Therefore, by examining the tables and figures presented here, the reader is cautioned against taking them for granted. Rather, they present a rough and lower estimate of what has to be expected realistically. Also, as official statistics relate only to occupational exposures and diseases that are part of the German list of occupational diseases (6), other possible occupational cancers are not considered here.

The Legal Basis of Compensation for Occupational Diseases in Germany
Occupational diseases have been compensated in Germany since 1925. They are defined by law [SGB VII §9(1)] (7) as diseases caused by exposures occuring more frequently among people at specific workplaces than in the general population. Occupational diseases are recognized as such by legal regulations (8) of the German government and are named individually in "Berufskrankheitenliste", which is updated about every 10 years. After the Second World War, East and West Germany took their own ways of updating the list of occupational diseases, but the principle mechanism of compensation remained the same for both. For a synopsis of malignant occupational diseases in East and West Germany before 1990, refer to Table 1. After the German unification there was a short transitional period (1991 to the end of 1993) in which occupational diseases were compensated according to both the standards of the former German Democratic Republic and the Federal Republic of Germany. Since 1994 new claims have been evaluated according to the law of the Federal Republic of Germany (7,8 Table 2, as well as the year when the disease was included in the list of occupational diseases (6). Some occupational diseases are defined by the necessary occupational exposure without localizing the disease (e.g., diseases caused by chromium or its compounds), others describe the disease as well (e.g., dysplasia or cancer of the urothelium caused by aromatic amines). Occupational diseases that are defined by their exposure only can apply to different diseases and can be malignant as well as nonmalignant. Most Group 1 carcinogens evaluated in the IARC monographs (9) are covered by the presently valid list (Table 3).
Once a disease is acknowledged as an occupational disease and becomes part of the list, it is not important in the compensation procedure whether individual lifestyle factors such as smoking contributed to the risk of getting the disease. Length of employment and latency period will usually be evaluated by an expert and become part of the final judgment as to whether it is plausible to assume an occupational disease, but these factors are not part of the definition of the occupational disease in the list. Compensations are paid by the compulsory accidental insurance system, which is divided into three major groups: the accident insurance of the industrial trade associations, the agricultural trade associations, and the public service. If there is new scientific evidence that a disease is caused by occupational exposure before a new revision of the list of occupational diseases is released, it can be compensated by way of exception according to SGB VII 59(2) (7).
Yearly statistics of all compensated occupational diseases are published in the "Bundesarbeitsblatt" (4) and by the top organization of accident insurance of the industrial trade associations for cancer [Hauptverband der gewerblichen Berufsgenossenschaften (HVBG)] (10) ( Table 4). As seen in Table 4, most occupational cancers occur in industrial workers and are compensated by the accident insurance of the industrial trade associations. Statistics on occupational cancer in East Germany until 1990 are presented in Table 5.

Many occupational diseases in West
Germany, especially those caused by chemical exposures, have a definition that does not allow to distinguish between malignant and nonmalignant conditions. The official statistics published in the "Bundesarbeitsblatt" are not very useful in this respect. More detailed information regarding cancer is available from a review report of the accident insurance of the bCicatrix cancer originating from conglomerated silicotic nodules. industrial trade associations (11). Data from Cancer Caused by that report are presented in the following Chemical Exposure paragraph and in Table 6, which also shows the mean of the duration of exposure and In East Germany 142 patients received latency in years and the age at diagnosis. compensation for occupational disease   (2), mostly for asbestosinduced cancer of the larynx (n= 33), which has been included in the list of occupational diseases only since 1997.

Cancer Caused by Ionizing Radiation
In the Middle Ages, silver was mined in the Ore Mountains of Saxony and Bohemia. Miners often died young of what was then called Schneeberger lung disease, named after a small town in the Ore Mountains. By the end of last century (12)(13)(14), it became apparent that lung cancer was the cause of death. Schneeberger lung cancer has been part of the list of occupational diseases since 1929. Compensation was hardly ever necessary until after World War II, when uranium mining was initiated on a large scale by the Soviet Union.
The uranium mining company Wismut Environmental Health Perspectives * Vol 107, Supplement 2 * May 1999  1960  1965  1970  1975  1980  1985 1990  90  Malignant neoplasms   3  2  9  7  6  3  7  of the skin  91  Malignant diseases  0  0  1  2  3  17  14  caused by chemicals  92  Malignant diseases caused  8  74  168  231  233  204 164  by ionizing radiation  93  Malignant diseases caused   1  2  5  44  99  209 363  by asbestos   Total  12  78  183  284  341  433   employed a total of at least 150,000 workers (men and women) underground. Working conditions before 1955 were poor. There was no artificial ventilation, and because of dry drilling, exposure to dust and a-radiation was very high. As seen in Figure 1, the number of compensated lung cancers increased steadily up to 200 to 300 cases per year from 1970 onward. When mining was discontinued in 1990, 5,700 patients with lung cancer had been compensated. For a sample of Wismut workers, the exposure history could be reconstructed. Having established the age distribution and taking into account the mortality from other causes, the expected age-specific mortality rates from lung cancer were calculated. Statistical risk models by Lubin et al. (15), Jacobi et al. (16), and BEIR IV (17) were applied. Assuming that for Saxony approximately 156,000 workers were exposed in underground mining and/or uranium processing, about 7,000 to 25,000 excess lung cancer cases are estimated to be due to exposure to radon and its progeny (past and future). When using the model from 1995 onward, about 1,300 to 4,800 additional cases are predicted in the population of exposed former Wismut workers in Saxony. The peak incidence was reached between 1985 and 1991 (18 it is now below 10,000 tons per year. In East Germany, asbestos import steadily increased from 8 What is surprising, though, is the short latency for asbestos-related lung cancer in East Germany, which may be explained by poor working conditions and high asbestos exposure in the late 1950s and early 1960s.
Cases of lung cancer compensated between 1978 and 1990 for West Germany and 1960Germany and 1965Germany and 1970Germany and 1975Germany and 1980 1985 1990 between 1991 and 1994 for all Germany Year were reported mainly from the following lumber of compensated lung cancer cases caused by ionizing radiation (no. 92) or caused by asbestos industries (11) (8) construction (n= 311). It is not known whether these industries also had the highest asbestos consumption. The jobs most often encountered were locksmiths (n = 347), chemical workers (n = 234), and plumbers and pipe fitters (n= 132). Cases of mesothelioma have been compensated in West Germany since 1977 ( Table 2) and in East Germany since the middle of the 1980s (3) as part of occupational disease number 93 (cancer caused by asbestos). The mesothelioma rate in West Germany was higher in 1985 and 1990 compared to lung cancer but lower in 1994 ( Figure 2). This is probably due to the fact that in 1993 the definition for the occupational disease number 4,104 changed. Formerly, for a compensation of lung cancer the radiologic evidence of lung asbestosis or pleural disease was necessary. After 1993 lung cancer cases were also compensated, if occupational exposure was at least that of 25 fiber-years (2 x 106 fibers/m3 x years) (17). Additional signs of asbestosis were no longer a prerequisite, which made compensation of lung cancer easier. Patients compensated for mesothelioma between 1978 and 1994 (9) had worked mainly in the following industries: iron and metal industry (n= 1107), chemical industry (n= 608), and light engineering and electrotechnics (n= 419). Jobs named most often were the same as for lung cancer: locksmiths (n = 535), chemical workers (n= 265), and plumbers and pipe fitters (n= 194).

Cancer of the Skin
Between 1978 and 1990, 123 patients with skin cancer were compensated in East Germany (3) and 69 were compensated in West Germany (11). After the unification until 1994, another 36 patients were compensated (11).