Cancer incidence following chlorophenol exposure in a community in southern Finland.

Chlorophenols have contaminated the drinking water system and the local lake in the village of J?rvel? in southern Finland. Local geology, ground water streams, and chemical analyses incriminated a local sawmill as the only plausible source of exposure. Cancer incidence in the municipality of K?rk?l? (half of the population lives in J?rvel?), compared with the rest of the local health-care district and with the greater cancer control region, indicated an excess of soft-tissue sarcomas and non-Hodgkin's lymphomas. A case-control study, which focused on cancers of the colon, bladder and soft tissues, lymphomas, and leukemia, demonstrated a significantly elevated risk ratio for non-Hodgkin's lymphomas among persons who consumed fish from the local lake, which was contaminated with chlorophenols. Probable exposure to chlorophenol-contaminated drinking water played a role in the increased incidence of non-Hodgkin's lymphomas and possibly was a factor in the development of soft-tissue sarcoma.     

Increase of specific symptoms after long-term use of chlorophenol polluted drinking water in a community

Chlorophenols contaminated the drinking water system and a local lake in the village of Järvelä in southern Finland. Period prevalence rates of symptoms, signs and diseases among the residents 15 years or older who responded (69%) to a survey in the contaminated area (1773 subjects) were compared with the rates of three uncontaminated areas (2018 subjects). Gastrointestinal and skin symptoms, in particular, were significantly (p < 0.05) more common in the contaminated area than in each control area. Nausea, general malaise, headache, anorexia, exceptional tiredness, and respiratory infections were significantly increased compared to the control areas combined. A dose–response was also observed: higher consumption of drinking water and contaminated fish further significantly increased (p < 0.05) reported symptoms. In conclusion, long-term use of chlorophenol polluted household water and fish can cause symptoms already familiar in connection with occupational chlorophenol exposures.     

Follow-up study of a pregnant woman 16 years after exposure in the Xinzhou radiation accident

To investigate the late effects of radiation on child-bearing women, a follow-up study was performed on a 39-year-old survivor 16 years after a (60)Co radiation accident. The woman, Fang, was 19 weeks pregnant at the time of exposure. Physical examinations, a full range of clinical laboratory and imaging tests, as well as cytogenetic analyses were conducted to evaluate Fang's current health conditions. Fang shows the appearance of premature ageing and has a decreased menstrual period. Laboratory studies and imaging tests suggest nodular goitre disease and osteoporosis. Otherwise, no apparent abnormalities were found in the major organs. No malignant tumours were detected by either tumour markers or imaging tests. However, the existence of chromosome aberrations warrants long-term follow-up for tumour incidence in the future. Fang became pregnant 8 years after the accident, but suffered a miscarriage due to the death of the foetus at 6 months into the pregnancy. In conclusion, our findings suggest that the intrauterine death of the foetus might be associated with the previous exposure. There is no evidence of malignant tumours as of the date of the follow-up study. Non-cancerous diseases, i.e. thyroid disease and osteoporosis, which may be related to radiation exposure, are the major manifestations of the long-term effects of the accident.     

Epidemiological study of nasal and nasopharyngeal cancer and their relation to phenoxy acid or chlorophenol exposure

Soft tissue sarcoma and malignant lymphoma have been related to exposure to chlorinated phenoxy acids or chlorophenols as well as exposure to organic solvents and malignant lymphoma. However, colon cancer studied by the same case-referent design did not show any such associations, which helps to rule out alleged systematical bias of the study approach. Further considerations about exposure routes for phenoxy acids and chlorophenols suggested that nasal and nasopharyngeal cancers should be studied. Forty-four cases with nasal cancer and 27 cases with nasopharyngeal cancer were eligible for study during 1970-1979 together with 541 referents, as utilized also in the aforementioned studies. Exposure to phenoxy acids gave formally a doubled but insignificant risk for the studied cancer types. Exposure to chlorophenols, as present particularly in woodwork, was related to an about sevenfold and significant increase in the risk for both cancer types. In woodworkers without exposure to chlorophenols there was an approximate normal risk, but cabinet makers, even without exposure to chlorophenols, had nearly doubled (but insignificant) risk of nasal cancer.     

Fonofos exposure and cancer incidence in the agricultural health study

BACKGROUND: The Agricultural Health Study (AHS) is a prospective cohort study of licensed pesticide applicators from Iowa and North Carolina enrolled 1993-1997 and followed for incident cancer through 2002. A previous investigation in this cohort linked exposure to the organophosphate fonofos with incident prostate cancer in subjects with family history of prostate cancer. OBJECTIVES: This finding along with findings of associations between organophosphate pesticides and cancer more broadly led to this study of fonofos and risk of any cancers among 45,372 pesticide applicators enrolled in the AHS. METHODS: Pesticide exposure and other data were collected using self-administered questionnaires. Poisson regression was used to calculate rate ratios (RRs) and 95% confidence intervals (CIs) while controlling for potential confounders. RESULTS: Relative to the unexposed, leukemia risk was elevated in the highest category of lifetime (RR = 2.24; 95% CI, 0.94-5.34, Ptrend = 0.07) and intensity-weighted exposure-days (RR = 2.67; 95% CI, 1.06-6.70, Ptrend = 0.04), a measure that takes into account factors that modify pesticide exposure. Although prostate cancer risk was unrelated to fonofos use overall, among applicators with a family history of prostate cancer, we observed a significant dose-response trend for lifetime exposure-days (Ptrend = 0.02, RR highest tertile vs. unexposed = 1.77, 95% CI, 1.03-3.05; RRinteraction = 1.28, 95% CI, 1.07-1.54). Intensity-weighted results were similar. No associations were observed with other examined cancer sites. CONCLUSIONS: Further study is warranted to confirm findings with respect to leukemia and determine whether genetic susceptibility modifies prostate cancer risk from pesticide exposure.     

Phorate exposure and incidence of cancer in the agricultural health study

BACKGROUND: We recently reported a link between use of the organophosphate pesticide phorate and risk of prostate cancer among applicators with a family history of prostate cancer in the Agricultural Health Study (AHS). OBJECTIVE: This finding, together with findings of associations between other organophosphate pesticides and cancer more broadly, prompted us to examine phorate exposure and overall cancer incidence in the AHS. Adding 3 years of follow-up and using more detailed exposure information allowed us to see whether the prostate cancer finding held. METHODS: The AHS is a prospective study of licensed restricted-use pesticide applicators from North Carolina and Iowa. To our knowledge, this is the largest examination of workers occupationally exposed to phorate. Pesticide exposure and other information was collected using two self-administered questionnaires completed from 1993 to 1997. Poisson regression was used to calculate rate ratios (RR) and 95% confidence intervals (CI), adjusting for potential confounders. RESULTS: Phorate use was not related to the incidence of all cancers combined or to any individual cancer, although we had insufficient numbers to study non-Hodgkin lymphoma or leukemia, which have been linked to organophosphates in other studies. Although prostate cancer risk was not significantly related to phorate use overall or among those without a family history, the risk tended to increase among applicators with a family history of prostate cancer. The interaction RR was 1.53 (95% CI, 0.99-2.37). CONCLUSION: The observed statistical interaction suggests a gene-environment interaction between family history and phorate exposure in the incidence of prostate cancer, but other explanations are also possible.     

Breast cancer incidence: geographical correlations in Finland.

Correlation analysis was performed on breast cancer incidence and risk factors in geographical areas of Finland. Breast cancer risk is associated with fertility and taxable income but not with the size of the woman. Trends in risk factors indicate that the rapid increase in the incidence of breast cancer is likely to continue. It is concluded that factors which are reflected by the standard of living and fertility might act independently and not through the nutritional status, for which the size of the woman is an operational indicator.     

Asthma incidence in wood-processing industries in Finland in a register-based population study

OBJECTIVES: This register-based population study determined incidence rates of clinically verified asthma among woodworkers, other blue-collar workers, and administrative personnel employed in wood-processing industries in Finland. Exposure to wood dust was under special scrutiny. METHODS: All Finns employed in wood-processing industries were followed for asthma incidence via record linkage in the years 1986-1998. Incident cases included people with asthma reimbursed for medication by the national health insurance or registered as having occupational asthma. Age-adjusted incidence rates and relative risks (RR) by gender were estimated for wood workers, other blue-collar workers, and administrative employees (referents) in wood industries. RESULTS: The relative risk of asthma was increased for all woodworkers among both genders [men: RR 1.5, 95% confidence interval (95% CI) 1.2-1.8; women: RR 1.5, 95% Cl 1.2-1.7]; a similarly elevated risk was also found for other blue-collar workers (men: RR 1.5, 95% Cl 1.2-1.8; women: RR 1.4, 95% Cl 1.2-1.6) in the same wood industries. Statistically increased relative risks were found for low and medium exposure to wood dust, but not for high exposure. Altogether 217 of the 4074 clinically verified asthma cases were reported as occupational asthma in the Finnish Register on Occupational Diseases. CONCLUSIONS: The incidence rates for asthma were significantly increased both among the woodworkers and the other blue-collar workers in wood industries but without a clear dose-response. Cases recognized as occupational asthma accounted for only a small part of the total asthma excess, indicating that much of the work-related asthma excess remains unrecognized in these industries.     

Follow-up survey of vasectomy in Finland

Résumé Cet article décrit les résultats d'une étude rétrospective, faite en moyenne 4,7 ans après vasectomie, auprès de 107 personnes ayant demandé une stérilisation en 1972/1973 et qui étaient en bonne santé psychique à ce moment-là. 24 % d'entre elles se sont déclarées très satisfaites de l'opération et 74 % se sont dites satisfaites; seules deux n'étaient pas satisfaites. Il n'a pas été noté de complications psychiatriques postvasectomie. Dans 32 % des cas est signalée une amélioration de la capacité et des pulsions sexuelles, alors qu'une diminution est signalée par 3 % des répondants.

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Follow-up study of vasectomy patients in Finland

Summary A follow-up study of 107 healthy males was conducted on average 4.7 years after vasectomy. Altogether 24 % of the subjects mentioned great satisfaction with the outcome of the surgical procedure; 74 % of the patients reported general satisfaction, and only 2 % appeared dissatisfied with regard to the performed vasectomy. In no instance had postoperative psychiatric complications been observed. In 32 % of the patients the sexual potency was said to have improved after vasectomy, whereas 3 % reported impairment of sexual function following the operation.

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Retrospektive Umfrage bei Vasektomiepatienten in Finnland

Zusammenfassung Bei 107 psychisch normalen Männern wurde in den Jahren 1972/73 eine Vasektomie durchgeführt. Sie wurden im Durchschnitt 4,7 Jahre nach der Operation nachuntersucht. 24 % der Patienten waren mit dem Operationsresultat sehr zufrieden, 74 % waren zufrieden und nur 2 % unzufrieden. Nach den Operationen sind keine psychiatrischen Komplikationen aufgetreten. In 32 % der Fälle wurde als Folge der Sterilisierung eine Verbesserung von Geschlechtstrieb und -fähigkeit beobachtet, während 3 % erklärten, als Folge des Eingriffs sei eine Schwächung der sexuellen Funktionen aufgetreten.

     

Effect of mustard gas exposure on incidence of lung cancer: a longitudinal study

Sulfur mustard, an agent used in chemical warfare, is an alkylating substance with carcinogenic potential. However, the precise long-term carcinogenic effects of mustard gas are unclear. Since 1952, the authors have conducted health surveys of former workers who were employed from 1929 to 1945 in a poisonous gas factory in Okuno-jima, Hiroshima, Japan. This prospective study was undertaken from 1952 to 2005 to examine the incidence of lung cancer among the workers who were exposed to mustard gas (n=480), lewisite (n=55), and/or diphenylcyanarsine (n=178), as well as the incidence among unexposed workers (n=969). The stochastic relation between exposure and lung cancer was explored on the basis of multistage carcinogenesis by using an accelerated hazard model with a transformed age scale. Mustard gas exposure was found to transform the age scale for developing lung cancer. One year of exposure in subjects ≤18 or >18 years old at first exposure shifted the age scale down by 4.9 years and 3.3 years, respectively. On the basis of the long-term follow-up of former workers in the poisonous gas factory, the authors concluded that sulfur mustard decreased the age at which people were at risk of developing lung cancer and that the effect declined with aging.     

Malathion exposure and the incidence of cancer in the agricultural health study

Malathion is the most common organophosphate insecticide applied in the United States, and while some studies suggest that it may be clastogenic, its carcinogenicity has not been demonstrated in rodents. However, malathion has been associated with non-Hodgkin's lymphoma in several epidemiologic studies. The authors investigated associations between malathion exposure and cancer among 19,717 pesticide applicators enrolled in the Agricultural Health Study between 1993 and 1997. Information on lifetime years and days per year of use and intensity of malathion exposure was obtained with self-administered questionnaires prior to the onset of any cancer. The average follow-up time was 7.5 years (1993-2002). Rate ratios and 95% confidence intervals were calculated using Poisson regression, adjusting for potential confounders. Overall, lifetime days of malathion use (top tertile of exposure, >39 days) was not associated with all cancers combined (rate ratio = 0.97, 95% confidence interval: 0.81, 1.15). The risk of non-Hodgkin's lymphoma was not associated with malathion use, although the number of cases was small. The risk of melanoma with more than 39 lifetime exposure-days was 0.39 (95% confidence interval: 0.14, 1.03). In summary, malathion exposure was not clearly associated with cancer at any of the sites examined. Although the rate ratios for melanoma were reduced, small numbers and lack of experimental evidence suggest that the observed reductions may have arisen by chance.     

Wood dust exposure and cancer incidence: a retrospective cohort study of furniture workers in Estonia

BACKGROUND: Occupational wood dust exposure is associated with increased risk of sinonasal cancer in men. However, little is known whether it is associated with sinonasal cancer in women or with malignancies of other sites. METHODS: In a retrospective cohort study of furniture workers, cancer incidence in 3723 men and 3063 women between 1968 and 1995 was compared to the incidence in the general population of Estonia. Cancer risks were analyzed by employment duration and occupation. RESULTS: The standardized incidence ratio (SIR) for all cancers did not differ significantly from one. Two men and one woman had sinonasal cancer (expected 1.07 and 0.53, respectively). Significantly increased risk of colon cancer was seen in the cohort (SIR 1.65, 95% confidence interval (CI) 1.22-2.17). Subjects employed for 10 years and over had significant excess of colon cancer (SIR 2.29, 95% CI 1.28-3.77) and rectal cancer (SIR 2.10, 95% CI 1.05-3.76) in the analysis by employment duration using exposure with a latency of 20 years. The nonsignificant excess of pharyngeal cancer in men (SIR 1.82) and lung cancer in women (SIR 1.43) was restricted to short-term workers. CONCLUSIONS: This study found an excess of colon and rectal cancer in furniture workers. There was no increase in total cancer risk.     

石家庄某高校学生结核病发病情况及随访观察

了解大学生的结核病发病情况及相关因素,为制定学校结核病防控措施提供依据.方法 选取河北经济管理学院2006级至2009级4届新生,按入学时的TB-PPD试验结果分为阴性组、一般阳性组和强阳性组,每届学生均观察3年,采用回顾性队列研究的方法对在校期间的结核病发病情况进行分析.结果 2006级至2009级共8 414人,有PPD结果8 394人,阳性率、强阳性率分别为2006级39.0%,12.1%;2007级33.6%,7.6%;2008级46.4%,11.2%;2009级50.4%,13.0%,各年级之间差异均有统计学意义(P值均<0.05).阳性率、强阳性率女生均高于男生,差异均有统计学意义(x2值分别为6.003,39.938,P值均<0.05).城市学生的阳性率(47.2%)高于农村学生(39.6%),强阳性率均为10.9%.累计观察25 242人年,共发现结核病人37例,年发病率为146.6/10万.PPD结果阴性组、一般阳性组、强阳性组的发病率差异有统计学意义(x2=132.720,P<0.01),发病率与强阳性率呈正相关(r=1.00,P<0.01).强阳性组中农村学生发病率高于城市(x2 =5.319,P=0.021).结论 青年学生是结核病的高危人群.应做为重点关注对象,给予适当的干预措施.     

A review of pesticide exposure and cancer incidence in the agricultural health study cohort

We reviewed epidemiologic evidence related to occupational pesticide exposures and cancer incidence in the Agricultural Health Study (AHS) cohort. Studies were identified from the AHS publication list available on a Medline/PubMed database search in March 2009. Findings related to lifetime-days and/or intensity-weighted lifetime-days of pesticide use are the primary focus of this review, because these measures allow for the evaluation of potential exposure-response relationships. Most of the 32 pesticides examined were not strongly associated with cancer incidence in pesticide applicators. Increased rate ratios and positive exposure-response patterns were reported for 12 pesticides currently registered in Canada and/or the United States. Exposure misclassification is also a concern in the AHS and may limit the analysis of exposure-response patterns. Epidemiologic evidence outside the AHS remains limited with respect to most of the observed associations, but animal toxicity data support the biological plausibility of relationships observed six pesticides. Continued follow-up is needed to clarify associations reported to date. In particular, further evaluation of registered pesticides is warranted.     

Use of exposure registration in the prevention of occupational cancer in Finland

A nationwide system for monitoring occupational exposure to a wide range of carcinogens has been in operation in Finland since 1979. The primary aim of the system is to lead to the identification, evaluation, and eventual elimination of the exposures. The number of exposed workers reported to the register was about 20,000 out of the work force of 2.3 million in 1979-1984. The most common exposures were chromates, nickel and its inorganic compounds, and asbestos. Data are presented to show that the system has been at least partially successful in decreasing exposures at work places. As an example, we discuss the decrease in the use of hydrazine, which was previously widely used as an anticorrosive agent at power plants. The statistical quality of the system is discussed, and possibilities for future research uses of the computerized data base are outlined.     

Reliability of retrospective chlorophenol exposure estimates over five decades

For a cohort study of chlorophenate-exposed sawmill workers, historical exposures from the 1940s to the 1980s were estimated by teams of 9–20 employees (each interviewed individually). The mill histories were divided into eras when jobs and exposures were relatively stable. Raters with at least 5 years of work experience in an era were asked to estimate the frequency and duration of exposure for each job in the mill. Reliability measures for these estimates were calculated for each of the 39 mill and time period combinations, using the individual intraclass correlation coefficient (ICC_ind) to assess agreement between raters and the group intraclass correlation coefficient (ICC_group) to assess the stability of the mean estimates of exposure. ICC_ind were low, with means that increased from 0.24 to 0.35 over the five decades. ICC_group were considerably higher (means increasing from 0.78 to 0.88 over time), indicating that the number of raters used in this study was sufficient to produce stable average estimates of exposure throughout the study period. These data confirm the intuitive expectation that reliability of exposure estimates decreases when reconstruction of conditions in the distant past is required, and therefore that the random component of exposure misclassification is a greater threat to validity in these earlier time periods. © 1996 Wiley-Liss, Inc.     

Population exposure to ultraviolet radiation in Finland 1920-1995: Exposure trends and a time-series analysis of exposure and cutaneous melanoma incidence

Ultraviolet radiation (UVR) is the principal cause of cutaneous malignant melanoma (CMM). However, the relation between CMM and UVR exposure is not clear. We present the trends of population exposure to UVR and conduct a time-series analysis of the relation between UVR exposure and incidence of CMM. Data on CMM incidence were obtained from the Finnish Cancer Registry. Clothing coverage of the body was scored from archival photographs and the proportion of uncovered skin was used as a measure of solar exposure. Information on the number of sunny resort holidays, duration of annual holidays, and sunscreen sales were obtained from various sources. Exposed skin area doubled from 1920 to 1985. The average duration of annual holidays increased 30-fold. The number of sunny resort holidays and the sales of sunscreens increased rapidly from 1980. CMM was most strongly associated with solar exposure of 5-19 years earlier. There is a considerable decrease in clothing coverage during the 20th century. UVR exposure preceding CMM occurrence 4 years or less does not appear relevant, whereas the period 5-19 years prior to CMM occurrence might be the most relevant period. However, findings of ecological studies may not be applicable at the individual level.