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Risk assessment/limit value setting for metals at the workplace is often based primarily on animal data. Epidemiological data providing information on quantitative exposure-response relationships is rarely available, but should be used preferentially if of sufficient quality, as in the case of chromium(VI). In Germany, the Committee of Hazardous Substances has derived an assessment criterion for chromium(VI) of 1 µg/m³ reflecting a tolerable risk of 4 additional cancer cases in 1000 workers exposed over their whole working life. For various metals human data is less informative. Thus, for cobalt, a tolerable concentration of 5 µg/m³ (respirable fraction) as been calculated based on inhalation studies in rats and mice which developed lung tumors after exposure to more than 1 mg/m³. However, recently published epidemiological studies among more than 30 000 hardmetal and cobalt production workers do not provide any evidence for carcinogenicity in humans at exposures in the range from 10–100 µg/m³ - between the tolerable concentration based on animal data and the concentration used in the animal experiments. The implications for risk assessment will be discussed also taking into account additional epidemiological data addressing potential inflammatory or fibrogenic effects with impairment of lung function at higher workplace exposures. Copper is another compound for which in Germany a limit value has been proposed by the MAK (maximal workplace concentration) commission based on animal data. Based on a 28 day rat inhalation study with copper(I) oxide which demonstrated inflammatory effects at concentrations starting around 200 µg/m³ a MAK value of 10 µg/m³ (respirable fraction) has been derived. However, copper has been used at workplaces for centuries at concentrations even in the mg range without observation of clear health effects. Potential explanations for these discrepancies as well as requirements of additional health data will be presented.

In the WELDOX study a statistical model of the exposure to respirable manganese (Mn) in welders, based on the applied welding technique, the material and its manganese content, the room conditions and the ventilation was estimated. Using this model, prediction and prediction intervals (PI) of exposure were calculated and made available in an easy to use web tool for industrial hygienists in order to estimate the airborne concentration. Between 2007 and 2009 personal sampling of respirable Mn was carried out in 241 welders during shift and information about the working conditions was gathered. The determinants of exposure concentrations were estimated with a multiple regression model that explained 72% of the variance. Prediction and 50%-, 80%- and 95%-PIs of Mn exposure were calculated and the results were graphically visualised. The predictions are valid for work places that are similar to the work places in the WELDOX study. A web tool was programmed and made available on a website. The user selects the applied welding technique, type of material and Mn content, room condition and the efficiency of the ventilation system. Then he receives the prognosed respirable Mn concentration with PIs. For example a welder applying tungsten inert gas welding with stainless steel with a Mn content of the material below 1.7% under normal room conditions without an efficient ventilation system has a prognosed concentration of 5.8 µg/m³ with 95%-PI 0.6 – 53 µg/m³. The presented web tool allows a fast prognosis of the respirable Mn exposure. It allows a quantitative prediction of the change of exposure concentrations when workplace characteristics are changed. Mn concentrations compiled in exposure databases may be helpful to validate the estimates.

Background High exposure to manganese (Mn) can cause movement disorders, but less is known if subclinical effects can occur at low doses or persist after termination of exposure. Objectives This study aimed to investigate the effect of exposure to Mn on fine motor deficits in a prospective cohort among elderly men from an industrial area with steel production. Methods Questionnaire-based data on occupations with exposure to Mn (mainly in the production and processing of steel) and fine motor tests were obtained in the second follow-up of the Heinz Nixdorf Recall Study (2011–2014). Occupational exposure to inhalable Mn was estimated for at-risk jobs based on 4,665 personal measurements and ancillary data on the workplaces between 1989 and 2015 compiled in the exposure database MEGA. Mn was determined in blood samples (MnB) archived at baseline (2000–2003). The study population included 1,232 men (median age 68 years). Regression models were applied to estimate the effects of working in at-risk occupations, MnB, and cumulative exposure to Mn on errors in line tracing, steadiness, or aiming and tapping hits with the non-dominant hand, adjusted for covariates. Results Median cumulative exposure to inhalable Mn was 58 µg/m³ years in 307 men who ever worked in at-risk occupations. Exposure in the highest quartile (>185 µg/m³ years) was associated with impaired tapping and line tracing. Baseline MnB above 15 µg/L was not associated with fine motor deficits. High age, low education and current smoking predicted impaired dexterity. Conclusion In this cohort of elderly men we found evidence that former exposure to Mn above 185 µg/m³ years may result in persistent fine motor deficits.

Powdered latex gloves or latex gloves with high allergen content are forbidden in Germany since 1998. It was the aim of this study to test the hypothesis that nationwide preventive measures enable health care workers with latex allergy to work without health risks about 10 years afterwards.Ninety-one health care workers who had been reported to the accident insurance between 1996 and 2004 for occupational latex allergy were examined in 2007. The survey included a questionnaire, a physical examination, spirometry, methacholine testing, skin prick testing and serum IgE measurements to latex and environmental allergens.Recent work-related possibly allergic symptoms were reported by 32 subjects (35%), among them 18 subjects (20%) with symptoms of the eyes, nose or airways. Current sensitization to latex was detected in 61 subjects (67%), and 60 subjects (66%) were atopic. Eleven subjects (12%) showed mild airway obstruction, and 27 subjects (30%) were considered hyperresponsive to methacholine. Whereas overall recent symptoms of the eyes, nose or airways were associated with current latex sensitization (OR 4.5; 95% CI 1.3-16.2), this was not the case for objective outcome parameters (spirometry, bronchial hyperresponsiveness).Although most subjects had only mild disease, ongoing work-related symptoms of the eyes, nose or airways in a substantial number of subjects with latex allergy suggest the need for further secondary preventive measures in German healthcare.

Students in the Penn State course entitled Problem Solving in Tropical Agriculture (INTAG 481) participated in an extended field trip to Puerto Rico. They were interviewed prior to boarding the plane about their expectations and what they had learned at the inception of the semester. The students were randomly selected for interviews. The interviews suggest that students perceived the field trip to Puerto Rico to be a significant and valuable learning experience that could not have been duplicated in the classroom. This direct, hands-on involvement and meaningful exposure to a "real world" situation provided a learning experience students recognized as being both valuable and unattainable within the confines of the classroom. Their learning experience included not only learning the content material but also applying what they learned, developing sensitivity to another culture, and growing personally and professionally.

Menopause timing has a major impact on infertility and risk of disease. Younger age at natural (nonsurgical) menopause (ANM) is associated with a higher risk of osteoporosis, cardiovascular disease, and type 2 diabetes and a lower risk of breast cancer. Late menopause is associated with a higher risk of breast cancer. It is well known that the age at which women go through menopause is partly determined by genes, but the underlying mechanisms are poorly understood. Genome-wide association studies have identified 18 common genetic variants associated with ANM. These variants explain less than 5% of the variation in ANM compared with the 21% explained by all common variants on genome-wide association study arrays. This genome-wide association study was the collaborative effort of researchers from 177 institutions worldwide. The study was designed to investigate genetic variants associated with timing of menopause among a population of approximately 70,000 women of European ancestry. A dual strategy was used to identify both common and, for the first time, low-frequency coding variants associated with ANM. The causal relationship between ANM and breast cancer was investigated using a Mendelian randomization approach. Combined analysis identified 1208 single-nucleotide polymorphisms (SNPs) of a total of approximately 2.6 million that reached the genome-wide significance threshold for association with ANM. Forty-four regions with common variants were identified; among these 44 loci were 2 rare low-frequency missense alleles of large effect. A majority of ANM SNPs were enriched in DNA damage response (DDR) genes, including the first common coding variant in BRCA1 associated with any complex trait. Mendelian randomization analyses supported a causal relationship between delayed ANM and breast cancer risk; there was approximately 6% increase in risk per year; P = 3 × 10-14); increased risk with delayed menopause appeared to be mediated primarily by prolonged sex hormone exposure in a woman’s lifetime, not DDR mechanisms. This is the first study to confirm the link between early and late menopause and breast cancer risk using genetic information. Age at natural menopause genetic variants influence breast cancer risk primarily through variation in menopause timing. Although carrying higher numbers of ANM-increasing variants and enrichment in DDR genes are associated with a modest increase in breast cancer risk, the major mechanism for increased risk appears to be prolonged estrogen and/or progesterone exposure due to delayed menopause.

Methacholine testing is one of the standard tools for the diagnosis of mild asthma, but there is little information about optimal outcome measures. In this study a total of 395 college students were tested by the ATS dosimeter protocol for methacholine testing, with minor modification. Body plethysmography and spirometry were measured after each inhalation step. The end-of-test-criteria were (i) decrease in forced expiratory volume in 1 s (FEV1) of ≥ 20 % and (ii) doubling of specific airway resistance and its increase to ≥ 2.0 kPa∙s. The results were expressed by receiver operating characteristic (ROC) plots using questionnaire answers as a reference. The areas under the ROC curves were iteratively calculated for a wide range of thresholds for both measures. We found that ROC plots showed maximal sensitivities of about 0.5–0.6 for FEV1 and about 0.7 for specific airway conductance (sGt), with similar specificities of about 0.7–0.8 taking questions with the known high specificity as references. Accordingly, larger maximal areas under the ROC curve were observed for body plethysmography, but the differences were small. A decrease in FEV1 of about 15 % and a decrease of sGt of about 60 % showed the largest areas under the ROC curves. In conclusion, body plethysmography yielded better sensitivity than spirometry, with similar specificity. However, replacing the common spirometric criterium for a positive test (20 % decrease in FEV1 from baseline) by the optimal body plethysmographic criterium would result in an increase of false positive tests from about 4 to 8 % in healthy young adults.

A 42-year-old female non-smoking onion and potato sorter developed work-related shortness of breath, cough, fatigue and flu-like symptoms. The diagnosis of hypersensitivity pneumonitis was based on patchy infiltrates in both lungs on high resolution computed tomography and lymphocytosis of 71% in a bronchoalveolar lavage sample with a CD4/CD8 ratio of 0.4. Exposure cessation and initial corticosteroid therapy resulted in complete recovery. IgG antibodies to Penicillium species and Fusarium solani cultivated from samples from the patient's workplace were detected in the patient's serum and cross-reactivity was demonstrated within Penicillium species, but also between Penicillium species and Aspergillus fumigatus. We conclude that occupational hypersensitivity pneumonitis due to molds may develop in onion and potato sorters.

A 62-year-old female sausage packer reported progressive work-related asthma, rhinitis and contact urticaria after contact to dry sausages refined by moulds. Whereas skin prick tests with commercial mould extracts were negative, the patient showed weak skin sensitization to a cultivated mould sample from a dry sausage. Specific immunoglobulin E antibodies to various moulds were demonstrated by ImmunoCAP and antibodies to the cultivated mould sample were demonstrated by enzyme allergosorbent test. The mould was identified by pheno- and genotyping as Penicillium camemberti. Five atopic controls did not show sensitization with the same tests. Crossreactivity of P. camemberti and Penicillium notatum was shown by enzyme allergosorbent inhibition tests. Although no challenge tests were considered due to the patient’s airway obstruction, a diagnosis of allergic occupational asthma was made. We conclude that immunoglobulin E-mediated allergic occupational asthma due to moulds may occur in dry sausage packers.

Cross-reactivity between grass pollen and grain flour allergens is well known, but their significance in apprentice bakers with primary sensitization to grass pollen is not known. Twenty-five subjects with mild asthma (most of them with hay fever), but without prior occupational flour exposure, underwent standardized experimental inhalation challenges with placebo and wheat and rye flours in randomized order on three consecutive days. Sensitization to flours and environmental allergens was assessed by skin prick tests and specific IgE antibodies in sera. IgE inhibition experiments were performed with wheat and rye flours as solid phases, and grass and tree pollen as inhibitors. Five subjects experienced a positive reaction after flour inhalation (responders), whereas 20 subjects did not show such a reaction (non-responders). All responders showed sensitizations to flours, whereas only 25% of the non-responders demonstrated the same sensitization. Specific IgE concentrations to flours, but also to grass and tree pollen, were higher in responders. Inhibition experiments demonstrated cross-reactivity between flours and grass or tree pollen, with higher inhibition rates in responders. Subjects with pronounced sensitizations to grass or tree pollen, but without prior occupational exposure to flours, may experience both sensitization and allergic asthmatic reactions to flours due to cross-reactive grass and tree pollen allergens.

Background Whereas platinum salts are well known occupational allergens, rhodium salts have not been identified as inhalative sensitizing substances. Methods A 27-year-old atopic operator of an electroplating plant developed work-related shortness of breath and runny nose with sneezing after exposure to rhodium salts. Quantitative skin prick tests (SPT) and bronchial challenge tests with a dosimeter protocol were performed with quadrupling doses of the sodium chloride salts of rhodium (Na3RhCl6) and platinum (Na2PtCl6). Results The patient showed positive SPT reactions and positive bronchial immediate-type reactions with rhodium and platinum salts. Sensitivity to rhodium salt was much higher than to platinum salt; the molar concentrations differed by a factor of 256 in SPT and a factor of 16 in bronchial challenges. Conclusions Rhodium salts should be considered as occupational immediate-type allergens. Am. J. Ind. Med. 53:42–46. 2010. © 2009 Wiley-Liss, Inc.

Summary Background Skin prick testing (SPT) is the basic method for diagnosing IgE-mediated allergies. However, skin reactivity is related to the quality of allergen extracts, which are often poorly defined for occupational allergens. Objective To compare wheat and rye flour SPT solutions from different producers. Materials and methods Standardized SPTs were performed in seven allergy centres with wheat and rye flour solutions from four producers in 125 symptomatic bakers. Optimal cut-off levels for weal sizes were assessed with the Youden Index. Comparisons between SPT results of different solutions were made with flour-specific IgE (sIgE) as the gold standard. Sensitivities, specificities, positive and negative predictive values, and test efficiencies were calculated and compared with McNemar and χ2-tests. The influence of the choice of the gold standard (sIgE or challenge) test was examined for 95 subjects. Additionally, SPT solutions were analysed for protein and antigen content. Results The optimal cut-off level for all SPT solutions was a weal size of 1.5 mm. While differences between wheat and rye flours were small, differences between producers were important. Variability of sensitivities (0.31–0.96), negative predictive values (0.42–0.91), and test efficiencies (0.54–0.90) were higher than variations of specificities (0.74–1.00) and positive predictive values (0.88–1.00). Similar results were obtained when using challenge test results as the gold standard. Variability could be explained by the different antigen contents of the SPT solutions. Conclusion There is a wide variability of SPT solutions for wheat and rye flour from different producers, mainly with respect to sensitivities, negative predictive values, and test efficiencies. Improvement and standardization of SPT solutions used for the diagnosis of baker's asthma are highly recommended.

To date, there is little information in the literature that hypersensitivity pneumonitis due to birds may occur without direct contact to birds. A 62-yr-old pensioner developed mild flu-like symptoms, fatigue and polyuria several hours after each meeting with his new female partner, either in hotels or his apartment. After divorcing from her ex-husband, who was a canary fancier, the female had moved into a bungalow approximately 6 months earlier. When the couple met for the first time at the bungalow, the patient's symptoms worsened and he developed shortness of breath. The patient had never entered the bird house or the married couple's house. Hypersensitivity pneumonitis was demonstrated by chest radiography, computed tomography, a restrictive ventilatory defect, decreased diffusion capacity and hypoxaemia after physical exercise. Sensitisation to canaries was shown by immunoassays. Canary antigens were detected by a polyclonal immunoassay at different locations of the married couple's house and the female's bungalow, where no birds had ever been kept. In conclusion, hypersensitivity pneumonitis should be recognised as a further consort disease, i.e. a disease that can be transmitted by partners.

Background: Wood dust is known to cause allergic occupational asthma and obeche (Triplochiton scleroxylon) is a prominent exponent in this field. However, the knowledge about wood allergens is still limited. The aim of this study was to identify and characterize obeche wood allergens. Methods: Obeche extracts were prepared from freshly ground in comparison to 7 years stored wood dust and investigated by Sodium dodecyl sulfate-polyacrylamid gel electrophoresis, enzyme-linked allergosorbent test and immunoglobulin (Ig)E-immunoblot. Allergens were detected by specific IgE of seven obeche allergic patients’ sera and protein analysis was performed by mass spectrometry. Cross-reactivity was demonstrated by ImmunoCAP-inhibition with sera of seven obeche and four latex-allergic patients. Results: Obeche extracts showed different protein pattern and IgE-binding capacities depend on the age of the wood dust. A 38 kDa protein was identified as major obeche wood allergen, detected by six of seven (85%) obeche allergic patients’ sera and was entitled as Trip s 1. Trip s 1 is homologous to plant class I chitinases and exhibited enzyme activity demonstrated by chitinolysis. Co-recognition or cross-reactivity of Trip s 1 according to structural similarity was seen in sera of latex allergic patients. IgE inhibition studies with obeche as solid phase and Trip s 1 and latex hevein as inhibitor demonstrated that Trip s 1 was a more effective inhibitor in obeche as well as in latex allergic patients’ sera. Conclusions: Trip s 1 is a new obeche wood allergen of the plant class I chitinase family. This finding may explain the dominant role of obeche in sensitization against wood dust.

As Chinese agricultural schools have gradually transferred from ineffective academic institutions to vocational education, the need for renewing teachers’ attitudes, knowledge, and skills to implement the curriculum innovations is evident. The purpose of this study was to describe teachers’ perceptions toward teacher training and reforms of curriculum and instruction in agricultural schools in China. The population for the study was teachers in 12 agricultural schools. A systematic random sampling technique generated a sample of 398 teacher participants. The results revealed that teachers supported curriculum reforms and they were interested in trying new ideas in their teaching practice. They believed that high quality of teacher training and professional development programs would help them to carry out the reform initiatives in curriculum and instruction. They also thought that knowledge and skills of teachers, attitudes of teachers, and new facilities and equipment were important factors affecting the process of curriculum reforms in agricultural schools. Therefore, policy makers and administrators should seize this opportunity to develop effective teacher education programs and address the needs of teachers in the process.

The purpose of this study was to identify the topics and teaching methods appropriate in a beginning international agriculture undergraduate course. A three round Delphi procedure was used to solicit expert opinions regarding important topics and effective teaching methods to deliver an international agriculture course for U.S. undergraduate students. The results revealed that the highest rated topics needed to be included in the international agriculture course were: role of agriculture in economic development; globalization and the implications/affect on agriculture; the role of culture in agricultural international development; definition of a developing country and a developed country; why a world-view is important to today’s agricultural producers and leaders; and agricultural extension and education systems in different countries. The top five teaching methods suggested by the panel of experts included experiential learning; presentations and dialog with those who have worked long term in relevant countries; field studies/trips to view various agricultural practices (one-three weeks); internships; and field trips to a country. Educators might consider the directions provided by this panel of experts when they develop coursework in international agriculture.

Agricultural schools in China have undergone numerous transitions as the system is shifting from non-effective academic institutions to vocational-oriented education brought by China’s economic reforms during the past two decades. Changes of traditional curricular and instructional methods have been recognized as an important strategy to strengthen vocational offerings of the existing agricultural educational system. The purpose of this study was to examine teachers’ current and desired knowledge and skills related to curriculum and instruction. The population for the study was teachers of 12 agricultural schools in China. A systematic randomization resulted in a sample of 398 participants from the population. A survey questionnaire was constructed and used to collect data from randomly selected teachers. The results showed that teachers indicated a significantly lower level of current knowledge and skill and they desired to have a higher level of knowledge and skills regarding curriculum and instruction. Teachers also indicated that they were particularly in lack of expertise in educational technology and curriculum and innovative teaching. Based on the results from this study, a need for teacher training and professional development is evident at these 12 schools. It is strongly recommended that teachers should be given opportunities and support to attend teacher training and professional development programs, which will increase their current knowledge base and enable them to successfully implement curriculum innovations.

Summary Platinum (Pt) salts are potent occupational allergens in precious metal refineries and catalyst productions. The threshold limit value of 2000 ng soluble Pt/m 3 enforced in many countries has been questioned because there is still a high incidence of Pt salt allergy. The objective of the present case series is to define the predictive value of biological monitoring by relating Pt in the serum of catalyst production workers and control subjects to sensitization to Pt salts as assessed by skin prick testing. A total of 38 Pt measurements were taken from sera of six workers investigated several times during a 5-year cohort study. Three subjects showed a conversion of skin prick test (SPT) with Pt salts from negative to positive during the cohort study (all considered highly exposed to Pt), and three did not show SPT conversion. Previous therapy with Pt-containing anti-cancer drugs and metallic dental alloys were considered as confounders. Only one of the three workers sensitized to Pt salt had clearly elevated serum Pt concentrations, but this elevation was not observed in each examination. Elevated Pt concentrations were also found in two subjects with low or no exposure to Pt. Both had metallic dental alloys. One control subject without metallic dental alloys showed low Pt concentrations in the serum in four examinations, but a single unexplained high concentration in his initial examination. In this small case series, serum Pt concentrations were neither sensitive nor specific for the prediction of Pt salt sensitization. Low specificity may be explained by Pt-containing metallic dental alloys, but additional unknown confounders may be of importance.

Background: Acid anhydrides are used in a variety of industrial branches because of their highly reactive anhydride groups. Adverse effects of anhydride exposure include toxic/irritative effects as well as IgE- and IgG-mediated respiratory disorders. It was the aim of this study to examine the usefulness of conjugates of pyromellitic dianhydride (PMDA) and laminin, a respiratory tract protein, for the in vitro diagnosis of sensitization to PMDA. Methods: Sera of PMDA-exposed workers (n = 9) and nonexposed controls (n = 8) were tested with an enzyme allergosorbent test (EAST). Human laminin and human serum albumin (HSA) were derivatized with PMDA and used as solid-phase in a commercial assay. Results: Seven out of 9 exposed workers revealed elevated IgE antibody concentrations (>0.35 kU/l) against laminin-PMDA whereas 5 of 9 subjects had elevated IgE antibody concentrations to HSA-PMDA. All 9 workers had elevated IgE antibody concentrations in at least one of the two tests. Of the 4 workers who complained of shortness of breath, 3 were positive for laminin-PMDA and 2 for HSA-PMDA. All of the nonexposed subjects were negative (Conclusion: PMDA-modified laminin could provide an additional diagnostic tool for the detection of sensitization to PMDA.

In response to the nation’s economic and agricultural system reform, Chinese agricultural schools have begun the transformation from academic institutions to vocational and technical education. Significant efforts have been made to reform the curricula, as it is the key element needed for the formation of the new educational system. Prior to the nation’s reform starting in 1978, the curriculum in agricultural schools was theoretical information based and the instruction was teacher-centered. Students usually had little involvement in teaching and learning. In addition, the value of practical “hands-on” experiences in agricultural education had been neglected. During the past decade new ideas and approaches in curriculum development and instruction have been gradually incorporated into the agricultural vocational education through new policy initiatives and a pilot project launched by the Food and Agriculture Organization of United Nations during 1994-1998. The decentralization is one major feature of these changes. Introduction/Background China is undergoing a large transformation as its economic system is shifting from a centrally planned to a market-driven system (State Council, 1999). Agriculture the traditional foundation of Chinese society faces an especially great challenge in restructuring its system to meet the needs of the market economy. In particular, agricultural education is playing an important role in preparing people for a new phase of rural development. During the past decade, agricultural schools have started to take actions to reform their existing educational systems and to strengthen their vocational programs (Ministry of Agriculture, 1997). There are 360 agricultural schools distributed among the provinces, autonomous regions, and municipalities throughout China. Agricultural schools are typically resident schools that require students to pass standardized admission exams. Schools usually enroll graduates from junior secondary schools and each program lasts for three or four years. The average enrollment for each school ranges from 1000-3000 students. One-third of agricultural schools are governed at the provincial level, while two-thirds are administered by prefectures. None of the schools falls directly under the Ministry of Agriculture (MOA). However, the Ministry undertakes the function of guidance and macro-management for all agricultural schools. In the past, agricultural schools were academic institutions classified as secondary specialized schools. The mission of these schools was officially described as to train intermediate-level specialists who were political and technical experts. Students were required to master basic theory, to have specialized knowledge, and to develop practical technical skills. Graduates from these schools were graded as “middle-level specialists” (Henze, 1984). Students were usually trained theoretically and narrowly. Most subjects studied in the schools were academic and usually had little relevance to the students’ workplace and reality. Upon leaving school, graduates were often assigned jobs according to a centrally organized plan. Just like graduates from higher education institutions or at least in theory every graduate would be assigned to a job position that could be characterized as “white collar.” In recent years, significant changes have taken place to reflect the continued reform and the development of the “socialist market economy.” Today, jobs for graduates are no longer guaranteed and the government can only hire approximately 50% of agricultural graduates (Chen, 2000). As a result, it is becoming increasingly difficult for an agricultural graduate to find a job in the public sector. Accordingly, graduates need to find their employment in the private sector or they need to be self-employed. Students’ education has become more purposive and selective, since it now must relate to their training and to employment opportunities in the labor market. Moreover, the feedback to schools has indicated

Objectives The role of occupational exposures in agricultural and industrial settings has been addressed in several breast cancer studies. Recently, the influence of shift work in nurses added as an occupational hazard that has been intensively discussed. Here, we investigate the association of job tasks in the industrial and health sector and breast cancer in a large case-control study. Method The population-based case-control study Gene-ENvironment Interaction and Breast CAncer (GENICA) was conducted in the Greater Region of Bonn, Germany. Occupational history and job task information were collected in computer-assisted interviews. Thirty pre-defined job tasks were assessed for 1143 cases and 1155 controls in addition to the occupational history. Risk estimates were calculated as odds ratios (ORs) with 95% confidence intervals (CIs) conditional on age and adjusted for potential confounders. Results First preliminary results indicate an increased age-adjusted risk for women who ever worked in anaesthesia (OR 1.87; 95% CI 1.03–8.0), based on fourteen cases and five controls. Conclusions Our study revealed an increased risk for ever working in anaesthesia. This elevated risk might origin from chemical exposures or night shift work. Interactions between exposures and night work might be relevant in the progression of breast cancer. However, the results of this study are limited by the low prevalence of risk jobs and specific exposures.

Golka and colleagues ([1][1]) critically refer to our observation that NAT2 genotype had no impact on bladder cancer risk ([2][2]). We were able to demonstrate in our case–control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC) that occupational exposure to

Objectives The aim of this analysis was to explore exposure to welding fumes and potential influencing factors of the airborne concentrations. Methods Personal sampling of welding fumes was carried out in 241 welders. Ninety respirable dust measurements were below the limits of detection (LOD). Therefore, we applied Tobit regression and imputations of values below LOD according to the log-normal distributions of the data ≥LOD with maximum likelihood estimation. We estimated regression coefficients for the welding processes, protective measures, and other factors. Results Main determinant of the concentrations was the type of welding process. The use of flux-cored wire in gas metal arc welding was estimated to increase the concentration in comparison with gas metal arc welding with solid wire (GMAW) by a factor of 2.20 (95% CI 1.58 to 3.06) using Tobit regression and by 2.36 (95% CI 1.51 to 3.69) using imputation. Tungsten inert gas welding was associated with 0.15 fold lower levels than with GMAW in both models. Dust extraction reduced the concentrations, whereas welding in confined space increased exposure levels with significant effects in both approaches. Conclusions Exposure to respirable welding fumes was frequently found below LOD. Two different approaches to deal with data

Objectives This investigation aimed to estimate predictors and associations of airborne and systemic exposure to manganese (Mn) and iron (Fe) among welders. Methods Personal air sampling of welding fumes was carried out in 241 welders during a shift. Metals were determined in the respirable and inhalable particle fraction. Mn in blood (MnB) and serum ferritin (SF) were determined in post-shift samples. The exposure variables were log-transformed for the estimation of predictors with multiple regression models. Results Respirable Mn ranged up to 2400 µg/m 3 (median 62 µg/m 3 ) and comprised 82% of the concentrations in the inhalable fraction. Inhalable Fe was twofold higher than respirable Fe. Mn was correlated with Fe (respirable fraction: r=0.92). Statistical modelling revealed a good model fit for both metals in the welding fumes. The concentrations were mainly predicted by the type of welding process and modified by workplace characteristics. Model building revealed an influence of the parent metal on MnB and SF, respectively. However, internal exposure levels were only weakly influenced by welding-related factors due to biological regulation. Median MnB was 10.30 µg/l, median SF 131 µg/l. MnB and SF were not correlated (r=0.08). Conclusions Welding resulted in similar Mn concentrations in both particle fractions of welding fumes, whereas inhalable Fe was twofold higher than respirable Fe. Biological regulation may at least partially explain the lack of association between MnB and SF. Mechanisms underlying Mn organ distribution and neurotoxicity need to be evaluated.

Background The risk of metastasis and the survival in patients with primary extremity soft tissue sarcomas is worse when tumour size is large and the grade of malignancy is high. Such tumours may receive chemotherapy and/or radiation therapy (RTX) for optimising local control. Irradiation can either be applied preoperatively or after tumour resection. The question arises if the kind of RTX in the absence of chemotherapy influences the outcome concerning local control, metastatic disease, survival and complications. Methods We retrospectively reviewed the clinical outcome of 233 patients with a primary extremity soft tissue sarcoma treated between 1990 – 2000 with a mean follow-up of 35.8 (4–120) months in our institute. 41 patients had high grade, deep and large tumours (>8 cm), an AJCC stage III (no evidence of metastasis prior to treatment) and were treated with limb salvage surgery and irradiation but stayed without additional chemotherapy. Two groups of patients were compared: the first group received postoperative RTX after tumour resection (n = 33); the second group was treated with preoperative RTX (n = 8). Both groups did not differ concerning clinical parameters. We analysed primary and secondary outcomes. Results 56% (23/41) of the population developed metastatic disease, 24% (10/41) local recurrence. The risk of metastasis was higher in the group with preoperative irradiation (p = 0.046). The overall (p = 0.0248) and relapse free survival (p = 0.104) were worse in this group. The delay to tumour resection amounted 8 weeks on average in the preoperative group. Local control was not different (p = 0.38) in both study groups. Wound infections and other combined therapy related complications were equally distributed (p = 0.22). Conclusion Without chemotherapy there remains a high risk of metastasis in AJCC grade 3 patients. In high risk patients treated without chemotherapy the elapsed time to tumour resection after preoperative radiation might contribute to the development of metastasis. This outcome may support the thesis that a combination of RTX and offensive multimodal treatment protocols is advantageous in such a subset of patients