Biomedical subjects

Katja Radon

Publications and source records attributed to Katja Radon.

At least 19 recordsLinked to original sources

PubMed2006

Adult obesity, farm childhood, and their effect on allergic sensitization.

BACKGROUND: Obesity as well as a reduced microbial exposure, 2 markers of Western lifestyle, might be associated with an increased risk of allergic sensitization. OBJECTIVE: We aimed to analyze the interplay of these markers of Western lifestyle on allergic sensitization. METHODS: A questionnaire survey was completed by rural adults (18-45 years). Clinical assessments included those of sensitization (specific IgE) against inhalant allergens and body mass index (BMI). Subjects were grouped on the basis of their recent BMI (obesity: BMI > or =30 kg/m2) and whether they had regular farm contact during the first 3 years of life (farm subjects). Nonobese nonfarm subjects served as the reference group. Overall, 1861 subjects were included in the analyses. RESULTS: Compared with nonobese nonfarm subjects, nonobese farm subjects showed a decreased odds ratio for sensitization (odds ratio, 0.6; 95% CI, 0.5-0.8). This decrease was not observed in obese subjects (obese nonfarm subjects: 1.2, 0.8-1.9; obese farm subjects: 1.0, 0.6-1.6). Associations were similar for symptoms of allergic rhinitis. CONCLUSION: Obesity, as a risk factor for respiratory allergies per se, might diminish or even cancel the protective effect of a farm childhood. CLINICAL IMPLICATIONS: The high prevalence of respiratory allergies in inner-city societies despite lower levels of hygiene might be explained by obesity.

Adolescent↗

PubMed2006

Geographical distribution of acute symptoms after a train collision involving epichlorohydrin exposure.

In September 2002, two freight trains collided in a northern German town. The inhabitants were potentially exposed to the probable human carcinogen epichlorohydrin. As no objective data on the level of exposure were available, we aimed to assess the geographical distribution of acute symptoms among local residents and subjects occupationally involved in the accident (e.g., firemen). A random sample of 932 adult local residents and 342 occupationally involved subjects were invited to answer a mail-in questionnaire. The main outcome measures were self-reported acute symptoms potentially associated with combustion products (e.g., irritation of the eyes, nose, or throat) and stress-related nonspecific symptoms. The main location during the first 26 h after the accident served as exposure proxy. For occupationally involved subjects, the time spent at the accident site was also used. The overall prevalence of symptoms potentially associated with combustion products was 9.8% for residents and 25.4% for occupationally involved subjects. After adjustment, subjects whose main location was close to the accident site had an increased risk for such symptoms. Among occupationally involved subjects the risk increased with duration at the accident site. Neither main location nor time at the accident site was significantly associated with non-specific symptoms. We could provide an example for designing and carrying out an epidemiologic study shortly after a local accident with potential public health impact. We could define parts of the population at increased risk for symptoms potentially specific for the exposure under study.

Accidents↗

PubMed2006

Acute blood neutrophilia induced by short-term compost dust exposure in previously unexposed healthy individuals.

OBJECTIVES: Systemic effects of organic dust inhalation have been described in farming environments. The purpose of this study was to examine whether a single exposure at a biowaste composting facility could also exert systemic effects in healthy volunteers not previously exposed to organic dust from such facilities. METHODS: Seventeen subjects (age 20-35 years) were exposed to organic dust for 2 h (exposure day) during moderate exercise; 12 of these subjects also took part in a control experiment (control day). Spirometry was performed before and immediately after the exposure. White blood cell counts and levels of tumor-necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) in peripheral blood were determined before and 3 h after exposure. RESULTS: Exposures did not result in significant changes in lung function or blood cytokine levels. In contrast, the number and percentage of neutrophils increased during the exposure day [median (range) percent change of percentages 14 (-2; 67) %; P=0.002], but not during the control day [5 (-22; 35) %; P=0.66). Furthermore, there was a decrease in the number and percentage of eosinophils during the exposure day [-47 (-57; 0.0) %; P=0.002], whereas the change during the control day was smaller [-8 (-56; 71) %; P=0.68]. CONCLUSION: Short-term exposure of healthy, young subjects to organic dust from composting facilities had opposite effects on the numbers of blood neutrophils and blood eosinophils. These effects, though mild, suggest that even during a limited period of moderate work a sufficient amount of bioactive material can be deposited in the lung to elicit acute systemic alterations.

Adult↗

PubMed2006

Personal dosimetry of exposure to mobile telephone base stations? An epidemiologic feasibility study comparing the Maschek dosimeter prototype and the Antennessa SP-090 system.

The aim of our study was to test the feasibility and reliability of personal dosimetry. Twenty-four hour exposure assessment was carried out in 42 children, 57 adolescents, and 64 adults using the Maschek dosimeter prototype. Self-reported exposure to mobile phone frequencies were compared with the dosimetry results. In addition, dosimetry readings of the Maschek device and those of the Antennessa DSP-090 were compared in 40 subjects. Self-reported exposures were not associated with dosimetry readings. The measurement results of the two dosimeters were in moderate agreement (r(Spearman) = 0.35; P = .03). Personal dosimetry for exposure to mobile phone base station might be feasible in epidemiologic studies. However, the consistency seems to be moderate.

Adolescent↗

PubMed2006

Adolescents' jobs and the course of dermatitis symptoms throughout puberty.

OBJECTIVES: This study evaluated the course of dermatitis symptoms throughout puberty taking into account occupational exposures in a population-based study. METHODS: Participants enrolled in the ISAAC-II (International Study of Asthma and Allergies in Childhood) study in Munich and Dresden in 1995 and 1996 were sent a postal questionnaire in 2002 (age at follow-up 16 to 18 years). The questionnaire included items on atopic diseases, jobs, including holiday jobs and vocational training, and potential confounders. The most recent of the adolescents' jobs held for at least 8 hours a week, and for at least 1 month, were coded according to the ISCO-88 system. RESULTS: Overall, data of 3785 adolescents were included in the analyses. The incidence of dermatitis symptoms during puberty among those without such symptoms at baseline was 7%. Altogether 31% of the participants reported an employment history. Those already employed were more likely to report a new onset of dermatitis symptoms. Jobs associated with a new onset of symptoms were work in the health care sector, vocational training in bakeries, and cleaning. The first 9 months of exposure were particularly relevant for new cases of dermatitis symptoms (odds ratio 3.7, 95% confidence interval 1.5-9.6). CONCLUSIONS: Early occupational exposure is associated with the development of symptoms of dermatitis. The types of skin alterations need to be assessed in the next stage of the study.

Adolescent↗

PubMed2006

Ambient endotoxin level in an area with intensive livestock production.

High levels of endotoxin are found inside and near to animal houses. However, there is a lack of data on environmental endotoxin in areas with intensive animal production facilities. We conducted a cross-sectional study of respiratory health in two villages of Lower Saxony with intensive livestock production. We assessed the level of endotoxin exposure in the backyards of 32 participants with two 24-hours measurements of inhalable fraction (one in winter and one in summer). The geometric mean (geometric standard deviation) of the levels of endotoxin varied between 2.0 (2.9) EU/m3 in winter and 2.9 (2.4) EU/m3 in summer. Potential predictors--season, sampling sites, and weather conditions--explained 24% of the variability in ambient endotoxin concentration in the study area. The results indicate that, compared with urban residents, exposure to endotoxin is greater among people living in rural areas with intensive animal production. This might affect their respiratory health. However, these exposures are characterized by a large spatial variability.

Air Pollutants, Occupational↗

PubMed2006

Case-based e-learning in occupational medicine--The NetWoRM Project in Germany.

The aim of the NetWoRM Project is the development, evaluation and implementation of a case-based e-learning tool for occupational medicine to increase the knowledge in clinical aspects of occupational medicine. To date, 19 e-learning cases have been developed. Cases were validated by 2 experts and user evaluated. Results of the user evaluation at 3 German Medical Schools are presented. Of 557 medical students registered for the online course 377 answered the online evaluation form (68%). Depending on the case, the median time spent on a case ranged from 25-43 minutes. Students enjoyed working with the cases and asked to replace more seminars by case-based e-learning. The level of knowledge required to work on the cases was rated high. This was supported by the fact that on median only 47-71% of the questions were answered correctly. Cases focusing on occupational health problems such as needle stick injuries were rated highest with respect to fun, importance for future career and the overall score. Students enjoy working on e-learning cases as an add-on to traditional teaching. Because of the high international interest the NetWoRM project is currently shared on an international base.

Computer-Assisted Instruction↗

PubMed2005

Lung function decline, chronic bronchitis, and occupational exposures in young adults.

RATIONALE: Occupational exposures to vapors, gas, dust, or fumes have been shown to be a risk factor of airway obstruction in cross-sectional studies in the general population. OBJECTIVES: Our aim was to study the relationships between specific occupations and occupational exposures during a 9-yr follow-up period and changes in lung function and symptoms of chronic bronchitis. METHODS: Subjects from the general population aged 20 to 45 yr were randomly selected in 1991-1993 within the European Community Respiratory Health Survey. Follow-up took place from 1998 to 2002 among 4,079 males and 4,461 females in 27 study centers. A total of 3,202 men and 3,279 women twice completed lung function measurements. Job history during follow-up was linked to a job exposure matrix and consequently translated into cumulative exposure estimates. MAIN RESULTS: Individuals exposed to dusts, gases, and fumes during the period of follow-up did not have a steeper decline of FEV1 than did individuals with consistently white-collar occupations without occupational exposures (relative change among men and women, + 1.4 and -3.1 ml/yr, respectively; p > 0.2), nor an increase of prevalence or incidence of airway obstruction defined as an FEV1/FVC ratio of less than 0.7. The incidence of chronic phlegm increased in men exposed to mineral dust (relative risk, 1.94 [1.29-2.91]) and gases and fumes (relative risk, 1.53 [0.99-2.36]), which was not modified by smoking. CONCLUSION: Occupational exposures to dusts, gases, and fumes occurring during the 1990s are associated with incidence of chronic bronchitis, although these did not impair lung function in a population of relatively young age.

Adult↗

PubMed2005

The physical and biological doses of methacholine are different for Mefar MB3 and Jaeger APS sidestream nebulizers.

BACKGROUND: Within a study on respiratory symptoms in rural areas, we used the European Community Respiratory Health Survey methacholine challenge protocol. For quicker and more reliable handling, we had to change the nebulizer in the bronchial challenge system from Mefar model MB3 (Bovezzo, Italy) to Jaeger APS Sidestream (similar to Mefar; Würzburg, Germany). Therefore, we compared the physical properties of the two systems, adapted the challenge protocol, and compared the results of both systems in subjects with and without airway hyperresponsiveness to methacholine. METHOD: The physical properties of both systems were characterized by the residual method indicating a similar particle size distribution and an average output of 6 muL/s for Mefar MB3 and 1.25 muL/s for APS Sidestream. In the comparison study, 34 subjects were included. Airway responsiveness was quantified by provocative dose of methacholine causing a 20% fall in FEV(1). RESULTS: A significant difference was found between the two challenge systems (p =0.004, McNemar test). Nine subjects reached a 20% drop in FEV(1) with the APS Sidestream only. The FEV(1) dropped by > 20% using either system in eight subjects. In 17 subjects, none of the two systems caused a 20% decrease in FEV(1). CONCLUSION: Even if the physical dose is determined with elaborate methods, the biological dose may vary between two nebulizer systems, causing incomparable outcomes for subjects tested with different systems.

Adult↗

PubMed2005

Exposure to farming environments in early life and type 1 diabetes: a case-control study.

It has been hypothesized that a stimulation of regulatory cytokines by microbial compounds reduces autoimmune as well as atopic diseases. Farm-related contact to microbial compounds protects from allergies, but no data on the association between farm contact and type 1 diabetes is available. The aim of this study was to test this association. A case-control study was conducted in five children's hospitals. Regular contact to farm animals and potential confounders were assessed using a postal questionnaire. Eligible subjects were all prevalent cases with type 1 diabetes registered in the hospitals and hospital-based control subjects (response rate 91%). Included were children aged 6-16 years living in rural areas with German nationality (242 case and 224 control subjects). Regular contact to stables (adjusted odds ratio 1.2 [95% CI 0.5-2.7]) was not associated with type 1 diabetes. In addition, regular contact to specific farm animals was not associated with case status. There was a tendency for an inverse relationship between allergic rhinitis and type 1 diabetes (0.6 [0.3-1.1]; P = 0.11). There was no evidence that early exposure to farm animals largely decreases the risk in children for developing type 1 diabetes.

Adolescent↗

PubMed2004

Childhood visits to animal buildings and atopic diseases in adulthood: an age-dependent relationship.

BACKGROUND: Several studies reported protective effects of farming environments against atopic diseases. Therefore, we aimed to establish the relevant timing of exposure in early life. METHODS: A cross-sectional study was carried out in a rural town. Overall, 4,537 inhabitants aged 18-44 years were eligible. Of these, 3,112 (69%) responded to a postal questionnaire on atopic diseases, life-time exposure to farming environments, and potential confounders. RESULTS: Those with regular childhood exposure to animal buildings had a significantly reduced risk of nasal allergies. The greatest reduction in risk was seen for respondents starting regular visits to animal stables during the 1st year of life or between ages 3 and 5. Participants reporting start of exposure after age 5 remained at a lower risk for nasal allergies (0.70, 0.49-1.01). CONCLUSIONS: The preventive effect of animal buildings' exposure against atopic respiratory diseases continues into adulthood. The magnitude of the effect appears to be age-dependent.

Adult↗

PubMed2004

Chlorophenol exposure in harbor workers exposed to river silt aerosols.

OBJECTIVES: While dredging the river Elbe in the harbor of Hamburg, workers are potentially exposed to river silt aerosols containing organic compounds. The aim of this cross-sectional study was to determine the internal load of chlorophenols in exposed workers. METHODS: Eighty-four exposed workers and eighty-four unexposed office workers were examined. Urinary samples were analyzed for dichlorophenols, trichlorophenols, tetrachlorophenols, and pentachlorophenol (PCP). RESULTS: For exposed workers, more than 2/3 of the urinary samples were above detection limit for 2,5-dichlorophenol, 2,4/3,4-dichlorophenol, 2,4,6-trichlorophenol, and PCP. Harbor workers had significantly higher median levels of 2,5-dichlorophenol (0.6 vs. 0.4 microg/g creatinine) and PCP (1.4 vs. 1.0 microg/g creatinine) as compared to unexposed subjects. These differences remained statistically significant after adjustment for age, smoking habits, and fish consumption. CONCLUSION: Harbor workers in the harbor of Hamburg have a statistically significant higher internal load of chlorophenols than the general population. However, the internal load is within the range of exposure reported from the general population. Therefore, even though chlorophenols are found in the river silt these exposures do not seem to be the major source of the internal load among workers in the harbor of Hamburg.

Adult↗

PubMed2004

Chronic obstructive pulmonary disease in never-smoking animal farmers working inside confinement buildings.

BACKGROUND: In animal farming, respiratory disease has been associated with indoor air contaminants and an excess in FEV1 decline. Our aim was to determine the characteristics and risk factors for chronic obstructive pulmonary disease (COPD) in never-smoking European farmers working inside animal confinement buildings. METHODS: A sample of participants in the European Farmers' Study was selected for a cross-sectional study assessing lung function and air contaminants. Dose-response relationships were assessed using logistic regression models. RESULTS: COPD was found in 18 of 105 farmers (45.1 SD 11.7 years) (17.1%); 8 cases (7.6%) with moderate and 3 cases (2.9%) with severe disease. Dust and endotoxin showed a dose-response relationship with COPD, with the highest prevalence of COPD in subjects with high dust (low=7.9%/high=31.6%) and endotoxin exposure (low=10.5%/high=20.0%). This association was statistically significant for dust in the multivariate analysis (OR 6.60, 95% CI 1.10-39.54). CONCLUSION: COPD in never-smoking animal farmers working inside confinement buildings is related to indoor dust exposure and may become severe.

Adult↗

PubMed2004

Livestock odours and quality of life of neighbouring residents.

Neighbours of intensive livestock production facilities frequently complain of odour annoyance. They are also concerned about potential negative health effects of environmental exposures to livestock emissions. Quality of life (QoL) was assessed in residents of a rural community neighbouring an area with high concentration of animal farms. A postal cross-sectional survey was carried out among the 4,537 residents, aged 18-44 years. Of these, 3,112 (69 %) responded to questions on annoyance by livestock odours (4-point scale), on QoL (assessed by the short form 12, SF-12), and on potential confounders (age, gender, respiratory symptoms, smoking, living on or close to a farm, and employment status). SF-12 scores were available for 2745 (88 %) subjects. Sixty-one percent of the respondents complained about unpleasant odours, 91 % of these accused livestock as source of these odours. Physical and emotional SF-12 scores were inversely related to annoyance scores. Better risk communication might improve QoL in concerned neighbours of intensive livestock production facilities.

Adaptation, Psychological↗

PubMed2003

Toxoplasma gondii infection, atopy and autoimmune disease.

While for many allergens a dose-response relationship has clearly been established the association between early childhood exposure to cat allergens and risk of sensitisation is still controversial and even inverse relations have been described. At the same time, a negative association between Toxoplasma gondii (T. gondii) infection and atopic diseases has been found in epidemiologic studies. As cats are the major source of T. gondii oocysts, we hypothesize that cat allergen exposure might be a confounder in the association between T. gondii infection and allergic diseases. Furthermore, it is well known that atopic diseases are T helper cell 2 (Th2) driven while autoimmune diseases are dominated by a Th1 response. A counterbalance between Th1 and Th2 cells has been postulated. However, it has been shown recently that subjects with autoimmune disease are more likely to suffer from atopic diseases. Therefore, similar cytokine profiles might underlie these disorders. If this holds true it can be hypothesised that T. gondii infection is associated with a lower prevalence of autoimmune disease.

Allergens↗

PubMed2003

Associations between ambient air pollution and daily mortality among persons with congestive heart failure.

We conducted a mortality time series study to investigate the association between daily mortality for congestive heart failure (CHF), and daily concentrations of particles and gaseous pollutants in the ambient air of Montreal, Quebec, during the period 1984-1993. In addition, using data from the universal Quebec Health Insurance Plan, we identified individuals >/=65 years of age who, one year before death, had a diagnosis of CHF. Fixed-site air pollution monitors in Montreal provided daily mean levels of pollutants. We regressed the logarithm of daily counts of mortality on the daily mean levels of each pollutant, after accounting for seasonal and subseasonal fluctuations in the mortality time series, non-Poisson dispersion, weather variables, and other gaseous and particle pollutants. Using cause of death information, we did not find any associations between daily mortality for CHF and any air pollutants. The analyses of CHF defined from the medical record showed positive associations with coefficient of haze, the extinction coefficient, SO(2), and NO(2). For example, the mean percent increase in daily mortality for an increase in the coefficient of haze across the interquartile range was 4.32% (95% CI: 0.95-7.80%) and for NO(2) it was 4.08% (95% CI: 0.59-7.68%). These effects were generally higher in the warm season.

Aged↗

PubMed2002

Uptake of antineoplastic agents in pharmacy personnel. Part II: study of work-related risk factors.

OBJECTIVES: This study aimed to find working conditions related to internal exposure of substances handled in centralised cytostatic drug preparation units in hospitals. Recommendations to avoid this uptake should be deduced from the results. METHOD: In a longitudinal study over 3 years, 87 pharmacy technicians and pharmacists of 14 different hospitals in Germany provided 24-h urine samples separately up to three times (three sampling cycles: cycles 1-3) at the end of a working week. Additional samples were taken after 2 days and after at least 3 weeks of absence. Cyclophosphamide and ifosfamide, doxo-, dauno- epi-, and idarubicin, and platinum deriving from cis- and carboplatin were determined in urine samples by gas chromatography/mass spectrometry, liquid chromatography (HPLC) and voltammetry. The following working conditions were assessed by questionnaire: working tasks, different ways that the workbenches were run, cleaning conditions, waste disposal, number of preparations, amount of substances handled, and use of gloves (material, thickness and changing interval). RESULTS: Two-thirds of the subjects showed at least one positive result with regard to all three cycles (56 of initially 87 subjects). Employees who only pass material that is needed for processing are affected, just as are those who only prepare administrations and those alternating in both functions (25% vs. 24.1% vs. 50.6%, respectively). The storage of waste in containers that could be opened to add waste tends to increase the risk of internal exposure of ifosfamide and cyclophosphamide (odds ratios (95% confidence interval): 0.08 (0.013-0.5) and 0.19 (0.03-1.12), respectively). The amount handled and number of preparations of cyclophosphamide for "manufacturers" were associated with internal exposure of cyclophosphamide (28.04 (1.75-448.74) and 1.22 (1.03-1.44), respectively). The total number of preparations handled by assistants seemed to increase the risk of intake of any of the substances under study [1.04 (1.00-1.08)]. CONCLUSION: Since employees who pass materials are affected in the same way as those who prepare administrations, both have to be included in reviewing protective measures. Further studies must be carried out to verify the generated hypotheses of factors related to internal exposure found in this study.

Adult↗

PubMed2002

Web-based training in occupational medicine.

OBJECTIVES: The aim of our project was to develop and evaluate an interactive computer-based approach to teach medical students in occupational medicine. To enhance interest in occupational medicine the major focus was on clinical and practical aspects of occupational medicine. METHODS: The computer program was designed in HTML and JavaScript. It presents a guided tour of the patient's case history followed by information on practice and theory of occupational medicine. The program was integrated into the curriculum during the summer term of 1999 and the following winter term. To assess the effectiveness and acceptability of the program we asked students to rate the program on an 18-item questionnaire. RESULTS: Overall, 287 students participated in the evaluation of the program. The participants highly recommended the program structure and had no difficulties in handling the program. This was independent of the computer experience of the students. The evaluation showed that it was possible to enhance interest in occupational medicine by using "virtual patients". CONCLUSION: The program represents a student-orientated learning tool that points out clinical and practical aspects of occupational medicine. The availability via the Internet allows the application as a self-learning tool as well as a teaching tool for the medical curriculum.

Humans↗