Bakery Workers Research Articles

A diagnostic model for the detection of sensitization to wheat allergens was developed and validated in bakery workers

Objectives To develop and validate a prediction model to detect sensitization to wheat allergens in bakery workers. Study Design and Setting The prediction model was developed in 867 Dutch bakery workers (development set, prevalence of sensitization 13%) and included questionnaire items (candidate predictors). First, principal component analysis was used to reduce the number of candidate predictors. Then, multivariable logistic regression analysis was used to develop the model. Internal validation and extent of optimism was assessed with bootstrapping. External validation was studied in 390 independent Dutch bakery workers (validation set, prevalence of sensitization 20%). Results The prediction model contained the predictors nasoconjunctival symptoms, asthma symptoms, shortness of breath and wheeze, work-related upper and lower respiratory symptoms, and traditional bakery. The model showed good discrimination with an area under the receiver operating characteristic (ROC) curve area of 0.76 (and 0.75 after internal validation). Application of the model in the validation set gave a reasonable discrimination (ROC area = 0.69) and good calibration after a small adjustment of the model intercept. Conclusion A simple model with questionnaire items only can be used to stratify bakers according to their risk of sensitization to wheat allergens. Its use may increase the cost-effectiveness of (subsequent) medical surveillance.

Application of a prediction model for work-related sensitisation in bakery workers

Identification of work-related allergy, particularly work-related asthma, in a (nationwide) medical surveillance programme among bakery workers requires an effective and efficient strategy. Bakers at high risk of having work-related allergy were indentified by use of a questionnaire-based prediction model for work-related sensitisation. The questionnaire was applied among 5,325 participating bakers. Sequential diagnostic investigations were performed only in those with an elevated risk. Performance of the model was evaluated in 674 randomly selected bakers who participated in the medical surveillance programme and the validation study. Clinical investigations were evaluated in the first 73 bakers referred at high risk. Overall 90% of bakers at risk of having asthma could be identified. Individuals at low risk showed 0.3-3.8% work-related respiratory symptoms, medication use or absenteeism. Predicting flour sensitisation by a simple questionnaire and score chart seems more effective at detecting work-related allergy than serology testing followed by clinical investigation in all immunoglobulin E class II-positive individuals. This prediction based stratification procedure appeared effective in detecting work-related allergy among bakers and can accurately be used for periodic examination, especially in small enterprises where delivery of adequate care is difficult. This approach may contribute to cost reduction.

Systems, Not Men: Producing People in Charlotte Perkins Gilman’s Herland

When Curt Muller required his female employees to work shifts in excess of ten hours at Grand Laundry in Portland, Oregon, it is unlikely he thought he was threatening future of human race. However, when he received a fine for overworking women in his laundry and contested fine's constitutionality before Supreme Court, Court's Justices would argue that matter of women's labor hours brought to fore precisely this issue. As first decade of twentieth century opened, labor reformers and captains of industry waged numerous battles over labor hours and conditions. Because stories of women and children suffering on factory floors gained sympathy for labor movement and sold newspapers, cases concerning women and minors typically led way for other labor regulations. In Supreme Court's 1908 ruling on Muller v. Oregon, Court found that a woman's special reproductive function could take precedence over freedom of contract established by due process clause in 14th Amendment. Muller is notable not just because it took an important first step in limiting demands employers could place upon workers, but also because it flew in face of Lochner v. New York (1905), and thus established a precedent for different treatment of men and women under law. In contradistinction to Lochner--which found that state could not legislate a maximum number of labor hours for male bakery workers without violating 14th Amendment--in his delivery of Court's opinion, Justice Brewer noted that although not all women are mothers, it is not unconstitutional to enforce a maximum number of labor hours for women because the of race justifies to protect her from greed as well as passions of men. Therefore, Justice Brewer notes, limitations which this statute [48 Or. 252] places upon her contractual powers, upon her fight to agree with her employer as to time she shall labor, are not imposed solely for her benefit, but also largely for benefit of all. The rhetoric in Brewer's opinion makes at least two important conversions: first, conversion of all women to mothers; second, a conversion of mothers to incomplete legal persons--persons who cannot fully exercise right to contract their labor. In other words, if ability to contract one's labor is a measure of legal personhood, Muller v. Oregon presupposes that protection of women and well-being of race requires legal limitation of this particular measure of personhood because as representative persons (mothers of race), women can never be same kind of legal persons that men are. Concerns about right to contract one's labor and definitions of personhood frequently intersected in American Progressive Era. In his reading of Muller Daniel Rodgers notes, From beginnings of protective labor legislation movement, assumption that women and children belonged in a separate, special category of workers had been central (239). One need only envision horror of 146 women burning alive or jumping to their deaths during Triangle Shirtwaist factory fire of 1911 to understand public concern about working conditions for women. Popular fiction and film from century's first decade, including Theodore Dreiser's Sister Carrie (1900) and white slavery film Traffic in Souls (1913), added a salacious undertone to physical risks female workers faced by drawing attention to unscrupulous men who might prey upon working girls. Furthermore, women may have been especially vulnerable to labor exploitation because union organizers typically overlooked female laborers in their organizing efforts. As Alice Kessler-Harris explains, out of all women engaged in industrial occupations in 1910 only 1.5 percent of these women were in unions (92). With women thus isolated from labor movement, sex-based legislation like Muller, paternalistic as its tone might be, may have been an important inroad to labor reform for female workers who were going largely ignored by American Federation of Labor. …

A dynamic population-based model for the development of work-related respiratory health effects among bakery workers

Objectives:This paper presents a dynamic population-based model for the development of sensitisation and respiratory symptoms in bakery workers. The model simulates a population of individual workers longitudinally and tracks the...

Construct validation in leadership research: Explication and illustration

The field of leadership typically employs constructs—variables that cannot be directly measured—in its research. Yet, our measures are rarely subjected to systematic assessment of their construct validity. This paper presents arguments about the importance of the construct validation process and illustrates why such concerns are well founded by examining the most commonly used measure of subordinate-perceived leader–member exchange, the LMX-7 scale. Using bakery workers ( N = 379) and employed MBA students ( N = 350), discriminant validity was investigated by exploratory factor analysis in the first sample, confirmatory factor analysis in the second sample, and correlation and multiple regression analysis in a subset of the second sample ( N = 220). The results suggested poor subordinate LMX-7 discriminant validity and that subordinate LMX-7 scores were substantially predicted by measures of supportive leadership and supervisor satisfaction ( R 2 = .71). Implications for future LMX theory and research are discussed as well as the types of construct validity evidence that we need to gather on our research instruments before and while they are employed in substantive studies of leadership phenomena.

Determinants of asthma phenotypes in supermarket bakery workers

While baker's asthma has been well described, various asthma phenotypes in bakery workers have yet to be characterised. Our study aims to describe the asthma phenotypes in supermarket bakery workers in relation to host risk factors and self-reported exposure to flour dust. A cross-sectional study of 517 supermarket bakery workers in 31 bakeries used a questionnaire, skin prick tests, and specific immunoglobulin E to wheat, rye and fungal alpha-amylase and methacholine challenge testing. The prevalence of probable occupational asthma (OA, 13%) was higher than atopic (6%), nonatopic (6%) and work-aggravated asthma (WAA, 3%) phenotypes. Previous episodes of high exposure to dusts, fumes and vapours causing asthma symptoms were more strongly associated with WAA (OR 5.8, 95% CI 1.7-19.2) than OA (2.8, 1.4-5.5). Work-related ocular-nasal symptoms were significantly associated with WAA (4.3, 1.3-13.8) and OA (3.1, 1.8-5.5). Bakers with OA had an increased odds ratio of reporting adverse reactions to ingested grain products (6.4, 2.0-19.8). OA is the most common phenotype among supermarket bakery workers. Analysis of risk factors contributes to defining clinical phenotypes, which will guide ongoing medical surveillance and clinical management of bakery workers.

Allergic sensitization in US bakery workers (140.9)

Abstract As part of a health hazard evaluation (HHE), the National Institute for Occupational Safety and Health (NIOSH) performed a study at a commercial bakery designed to evaluate allergic sensitization to bakery associated allergens (BAA; alpha-amylase, [AA]; wheat, [W], or flour dust, [FD]). Sera was obtained from 96 employees, dichotomized as having low exposure (N=33) or high (or past) exposure (N=63) to BAA. Workers were evaluated for atopy (AlaTOP®, total IgE), and serum-specific IgE (AA, FD, and W; IMMULITE® 2000). There was no significant difference in the prevalence of atopy between groups by AlaTOP® (47% of high exposure vs. 41% of low exposure, p=0.6) or total IgE (3.9 kU/L [high exposure] compared to 3.7 kU/L [low exposure], p=0.5). At an IMMULITE® specific IgE cutoff of > 0.35 kU/L, there was significantly greater prevalence of positive specific IgE to W. When an IMMULITE® positive cutoff of >0.10 was used, significantly greater prevalence (p<0.05) of specific IgE to FD, AA, and W was observed in the high vs. low exposure groups. Atopics had significantly higher rates of sensitization to W and FD at both the 0.1 and 0.35 kU/L levels, and to AA at the 0.1 level. Exposure to BAA puts workers at a higher risk for sensitization to BAA (specific IgE). As has been shown for other occupational allergens (Annals of Allergy, Asthma, & Immunology, 97:196-202, 2006), using the IMMULITE® at a cutoff of 0.10 kU/L vs. 0.35 kU/L appears to increase the sensitivity of the assay.

Application of a dynamic population-based model for evaluation of exposure reduction strategies in the baking industry

Recently a dynamic population model was developed that simulates a population of bakery workers longitudinally through time and tracks the development of work-related sensitisation and respiratory symptoms in each worker. Input for this model comes from cross-sectional and longitudinal epidemiological studies which allowed estimation of exposure response relationships and disease transition probabilities This model allows us to study the development of diseases and transitions between disease states over time in relation to determinants of disease including flour dust and/or allergen exposure. Furthermore it enables more realistic modelling of the health impact of different intervention strategies at the workplace (e.g. changes in exposure may take several years to impact on ill-health and often occur as a gradual trend). A large dataset of individual full-shift exposure measurements and real-time exposure measurements were used to obtain detailed insight into the effectiveness of control measures and other determinants of exposure. Given this information a population wide reduction of the median exposure with 50% was evaluated in this paper.

Wheat allergen exposure and the prevalence of work‐related sensitization and allergy in bakery workers

Occupational airway diseases are common among bakers. The present study describes the association between exposure to wheat allergen levels and sensitization to wheat allergens, work-related upper and lower respiratory symptoms and asthma in bakery workers. As part of a Health Surveillance System for early detection of (allergic) occupational airway diseases a so-called 'validation study' was performed among Dutch bakers for validation of a diagnostic model that predict the likelihood of sensitization to specific workplace allergens. The present study used serology and questionnaire results of a subgroup of 860 bakers participating in the validation study. An earlier developed job-exposure matrix was used to predict average and cumulative personal exposure to wheat allergens. The prevalence of wheat sensitization, work-related respiratory symptoms and asthma increased till average wheat exposure levels of approximately 25-30 microg/m3, leveled off and decreased at higher exposure concentrations. Exposure-response curves showed a stronger pronounced bell-shape with cumulative exposure. Associations were strongest for asthma and work-related lower respiratory symptoms (PR approximately 2 and PR approximately 3.5-4.5 for average and cumulative exposure, respectively). Associations were only found in atopics. Wheat sensitization was an important factor in the prevalence of respiratory symptoms. In accordance with earlier studies, the present study showed a bell-shaped exposure-response relationship especially for cumulative wheat allergen exposure with sensitization, allergic respiratory symptoms and asthma. The healthy worker effect may be the possible explanation for the bell-shaped relationship.

Rye flour allergens: An emerging role in baker's asthma

Exposure to wheat flour is usually considered the most important cause of baker's asthma. However, other flours frequently used in bakeries may play an emerging role as relevant allergens causing occupational asthma. We report on two cases of baker's asthma mainly caused by exposure to rye flour. The profile of allergen sensitization to cereal flour was investigated. Two bakery workers suffering from rhinoconjunctivitis and asthma symptoms at work underwent an in vivo study (skin prick tests and bronchial allergen challenge) and in vitro study (total serum IgE, specific serum IgE and immunoblotting). Specific inhalation challenge with wheat flour did not elicit an asthmatic reaction, however both patients showed an early asthmatic reaction with the rye flour challenge. Rye flour-immunoblotting showed IgE-binding bands around 12-15 kDa, that correspond to rye flour enzymatic inhibitors which were not present in the wheat flour immunoblot. Both bakers had developed occupational asthma to rye flour (confirmed by specific inhalation challenge test). Rye flour allergens (enzymatic inhibitors) are important allergens that should be considered in the diagnosis of baker's asthma.

Prevalence of work-related symptoms and serum-specific antibodies to wheat flour in exposed workers in the bakery industry

Although baker's asthma (BA) is a common occupational asthma, there have been few reports on this disease in Korean subjects. We evaluated the prevalence of serum-specific IgE, IgG1, and IgG4 antibodies in relation to work-related respiratory symptoms in a single industrial bakery. Three hundred and ninety-two bakery workers were administered and taken a questionnaire regarding respiratory symptoms. For symptomatic workers, the methacholine bronchial challenge test and specific bronchoprovocation tests with wheat extracts were carried out. Skin prick tests were performed and serum-specific IgE, IgG1, and IgG4 antibodies to wheat flour were detected. The IgE- and IgG4-binding components were identified by immunoblotting. Sixty-seven workers (17.1%) complained of work-related upper and lower respiratory symptoms. The prevalence of BA based on positive bronchoprovocation test results was 1.5%. The sensitization rate to wheat flour was 5.9% by skin prick test and 6.5% by ELISA, and was closely associated with the presence of atopy and work-related lower respiratory symptoms (P<0.001 for both). IgE immunoblotting revealed six major IgE-binding components (27, 31, 36, 43, 54, and 72 kDa). The presence of wheat-specific IgG1 and IgG4 antibodies was found to be significantly associated with exposure intensity (P<0.05 for both). The overall prevalence of wheat sensitization in a Korean bakery was 5.9%. We confirmed that an IgE-mediated response is the major pathogenic mechanism for the induction of work-related symptoms in wheat-exposed workers. Wheat-specific IgG antibodies may represent current or previous exposure to wheat dust.

Prevalence of asthma and rhinitis in bakery workers in the city of Sanandaj, Iran.

Baker's asthma is one of the most common forms of occupational asthma. This study was conducted to determine prevalence of asthma and rhinitis among bakery workers in the city of Sanandaj, the provincial center of Kurdistan province in the west of Iran in the in Summer 2006. In this study 776 bread bakery workers were included. These subjects were selected randomly among 1620 bakery workers. The diagnosis of asthma was based on a medical history of episodic symptoms of cough, chest tightness, and dyspnea and spirometry. Airflow obstruction was determined with spirometry, the definition of airflow obstruction which was used in this study was an FEV1/FVC ratio < 0.8, and FEV1 or FVC increases of > or = 12 percent and at least 200 mL after using a short-acting inhaled beta2-agonist. Rhinitis was diagnosed by typical history of work related symptoms. Analyses were performed on 776 subjects (all were men) without missing data for asthma and rhinitis. All of subjects were male with mean age of 33.69+/-11.09 years. Mean duration of bakery working for these subjects was 13.91+/-9.37 years. Prevalence of asthma at the time of study was 11.9%. 93 subjects were diagnosed as asthma with history, physical and spirometry findings. 31 (33.3%) of asthmatic workers were diagnosed as asthma previously and 62 (66.6%) workers were known as new asthmatic patients which were diagnosed in this study program. The prevalence of rhinitis was (9.9%). Subjects with asthma had longer history of working at bakery than others (P=0.001). Asthma prevalence among these bakery workers that were included in our study was similar and in some instances the prevalence was lower than other studies.

Determinants of elevated exhaled nitric oxide (eNO) among bakery workers in South Africa

Determinants of elevated exhaled nitric oxide (eNO) among bakery workers in South Africa

Predictors of work-related symptoms, allergic sensitisation and occupational asthma among supermarket bakery workers in South Africa

Predictors of work-related symptoms, allergic sensitisation and occupational asthma among supermarket bakery workers in South Africa

Inhalable β(1→3)glucans as a non-allergenic exposure factor in Dutch bakeries

Objectives:To obtain an overview of inhalable β(1→3)glucans levels in Dutch industrial bakeries and explore possible associations with reported respiratory health effects in bakery workers.Methods:β(1→3)glucan levels were analysed in 186 personal...

Work-related chronic venous disease in office and bakery workers

A prospective study was undertaken in order to establish the prevalence and risk factors of chronic venous disease (CVD) in two occupational groups: office employees working in a prolonged sitting or standing position, and people working in bakeries, in a hot microclimate. It included 160 individuals over 40 years old, 97 women and 63 men. A survey assessing subjects' work place ergonomics, Doppler sonography – currently the diagnostic tool of choice in the assessment of sufficiency of venous valves, and an observational study were performed. Doppler signs of CVD in persons working in sitting or standing positions and in hot microclimate were found in 59.4%, 83.4% and in 76.4%, respectively. Most often diagnosed were perforating veins and vena saphena magna incompetence. Occurrence of CVD was significantly higher in people working in a standing position than in those working in a sitting position (p-value =0.0145). Occurrence of CVD among office workers working in sitting or static standing conditions and among people working in a hot microclimate were comparable (p-values =0.1152 and 0.7116, respectively). Conclusions: Occupational CVD is a frequent condition among office workers and people working in a hot microclimate. Static standing position at work constitutes a significantly greater risk for CVD development than prolonged sitting or work in a hot microclimate and thus should be a subject for specific prophylaxis interventions.

Bronchial responsiveness in bakery workers: relation to airway symptoms, IgE sensitization, nasal indices of inflammation, flour dust exposure and smoking

Bronchial hyperresponsiveness (BHR) is common in bakery workers. The relation between bronchial responsiveness measured with a tidal breathing method and smoking, airway symptoms, IgE-sensitization, nasal indices of inflammation and flour dust exposure have been studied with bronchial responsiveness expressed as a continuous outcome. Bakery workers (n = 197) were subjected to interviews, questionnaires, allergy tests, workplace dust measurements and bronchial metacholine provocation. Eosinophil cationic protein (ECP) and alpha(2)-macroglobulin were measured in nasal lavage. Bronchial responsiveness was expressed as slope(conc), a measurement based on regressing the per cent reduction in FEV(1) at each provocation step. BHR expressed as slope(conc) was associated with smoking (P = 0.009), asthma symptoms at work (P = 0.001), and occupational IgE sensitization (P = 0.048). After adjusting for baseline lung function the association between BHR and IgE sensitization was no longer present. We demonstrated an association between nasal ECP and BHR (slope(conc) < 3: P = 0.012), but not to alpha(2)-macroglobulin in nasal lavage. No association was seen between BHR and current exposure level of flour dust, number of working years in a bakery or a history of dough-making. BHR is related to baseline lung function, work-related asthma symptoms, smoking and nasal eosinophil activity, but not to occupational IgE sensitization and current flour dust exposure when measured with metacholine provocation. The slope(conc) expression seems to be a useful continuous outcome in bronchial responsiveness testing.

Allergy in bakers’ apprentices and factors associated to non-participation in a cohort study of allergic sensitization

To describe the prevalence of atopy and respiratory symptoms among baker apprentices at the start of the education and factors associated with non-participation in the study. A total of 346 students, 22.1(0.6) years of age, mean (SD), from the food production programme of technical colleges in Denmark were invited to participate in a 3 year study. Of the students, 187 agreed to participate and filled in a physician-administered questionnaire. The presence of atopy was determined by skin prick test (SPT) and serum allergen specific IgE (SpIgE). Bronchial hyper responsiveness to methacholine (PD(20) <or= 1,440 microg) was determined. Prevalence of atopy was 32%. The prevalence of symptoms from the lungs and nose was 19.8 and 25.5%, respectively. Significantly, more SPT reactions were seen in males compared to females (39 vs. 22%, P < 0.05). Sensitization towards flour was significantly more frequent if determined as SpIgE (7.3%) compared to SPT (0.5%). We found a positive association between atopy and lung symptoms OR 6.1 (2.8-13.2 SD) and nasal symptoms OR 3.7 (1.8-7.5 SD). The major reason for non-participation was fear of blood sampling (25.5%). The prevalence of atopy in bakers' apprentices was of the same magnitude in the general Danish population. Significantly, more male bakers' apprentices had atopy. This finding has major impact on the diagnostic procedures of occupational allergy in bakery workers emphasizing the need for standardization of the clinical tests. The main reasons for non-participation were, fear of blood-sampling (57%) and the 3 years commitment to the follow-up study (39%).

Assessment of Nasal Swab Samples, Environmental Microbiological Analyses and Respiratory Function Tests of Bakery Workers Working Under Modern Conditions: A Brief Report

Studies have shown that bakery workers may develop asthma and rhinitis as a result of their occupation and approximately 30% of bakery workers and wheat farmers will become sensitised. This ratio can change depending on the exposure time and a history of atopy. The present study has looked at the relationship between nasal and environmental flora and pulmonary function in such workers to see if it can explain the occurrence of asthma and rhinitis. Workers from three of the largest bakery companies in Istanbul were recruited, a total of 372 people; 223 bakery workers and 149 administrative employees of the same companies as a control group. Face to face interviews were conducted to determine asthma status and all were given physical examinations with nasal flora samples collected by sterile swabs. Aerial samples were taken from administrative and product departments for microscopic examination. Compared to administrative staff, bakery workers had insignificantly more asthma symptoms (p&gt; 0.05). C. albicanswas isolated from four (1.9%) nasal samples from bakery workers and one (0.7%) from the control group (p&gt; 0.05). A statistically significant level of wheeze (X2= 4.65, p= 0.03, OR= 2.32 95% CI (1.06–5.07)), suggesting bronchial obstruction, was detected in 28 (13.1%) bakery workers and in nine people (6.1%) from the control group. Looking at smoking and non-smoking groups, a significant decrease was observed for PEF (%) in the smokers and FEV1/FVC (%) in the non-smokers. These results suggest that pulmonary function of bakery workers is slightly impaired even with modern engineering controls.

Wheat and maize thioredoxins: A novel cross-reactive cereal allergen family related to baker's asthma

Baker's asthma is a serious problem for a significant proportion of workers in bakeries, confectionaries, and the food industry. Although several wheat allergens related to baker's asthma have been described, standardized reagents for a reliable diagnosis are not yet available. To clone novel wheat allergens related to baker's asthma and investigate the cross-reactive potential of their maize and human homologues. A wheat cDNA phage display library was screened with sera from bakers with occupational asthma for IgE-binding structures. Homologous sequences from maize and human thioredoxins were amplified from corresponding cDNA libraries. Within the enriched wheat cDNA repertoire we identified, among others, the sequence encoding wheat thioredoxin-hB (Triticum aestivum allergen 25 [Tri a 25]). The recombinant protein displayed enzymatic activity, and we observed a sensitization rate of 47% among bakers with occupational asthma and of 35% among patients with grass pollen allergy, but without a clinical history of cereal allergy. Furthermore, the previously characterized maize thioredoxin-h1 (Zea mays allergen 25 [Zea m 25]), sharing 74% identity with Tri a 25, exhibited distinct IgE cross-reactivity with its wheat homologue. Two bakers also showed sensitization to human thioredoxin, which shares 29% identity with Tri a 25. In a comparative study, we included recombinant alpha-amylase inhibitor 0.19, showing a sensitization rate of 65% in individuals with baker's asthma. Thioredoxins represent a novel family of cross-reactive allergens that might contribute to the symptoms of baker's asthma and might in addition be related to grass pollen allergy, as indicated by the reactivity of grass pollen allergic patients to cereal thioredoxins. The recombinant cereal thioredoxins will, together with the already reported wheat allergens, contribute to a more reliable diagnosis of baker's asthma and, perhaps, become a tool for the development of component-resolved immunotherapy.