Flour exposure, sensitization and respiratory health among Alberta trainee bakers

BACKGROUND

Sensitization to allergens encountered in baking, and allergic disease including asthma and rhinitis, is recognized. Attempts to reduce this risk have been instituted in some workplaces, but awareness remains low. This study aimed to quantify the current risk among Alberta bakers.

AIMS

To estimate the onset of sensitization to bakery allergens and allergic disease among trainee bakers at the outset of their career.

METHODS

Trainees attending one of the two bakery programmes were recruited between 2015 and 2018. At entry, an interview was held and spirometry and skin prick tests were performed. Participants were contacted every 6 months by telephone or online interview for 3 years to update work and health information. An exit interview was completed between 2018 and 2019 for all who could be contacted. Exposure was estimated using collected work history and a job exposure matrix was prepared for this study.

RESULTS

A total of 220 individuals participated in the entry interview, 204 completed one or more periodic interviews and 113 completed the exit interview. Six who completed exit testing developed new sensitization to bakery antigens, an incidence of 2.49/100 person-years. Positive skin prick tests for bakery antigens were associated with bread making. Rhinitis symptoms were associated with total flour dust and new-onset rhinitis to months in trade. New-onset asthma was related to cumulative exposure to flour improvers.

CONCLUSIONS

Trainee bakers in Alberta remain at risk of sensitization and occupational respiratory disease.

Respiratory health, occupation and the healthy worker effect

BACKGROUND

Workers are exposed to physical, chemical and other hazards in the workplace, which may impact their respiratory health.

AIMS

To examine the healthy worker effect in the Canadian working population and to identify the association between occupation and respiratory health.

METHODS

Data from four cycles of the Canadian Health Measures Survey were utilized. The current occupation of employed participants was classified into 10 broad categories based on National Occupation Category 2011 codes. Data relating to 15 400 subjects were analysed.

RESULTS

A significantly lower proportion of those in current employment than those not in current employment reported respiratory symptoms or diseases or had airway obstruction. Similarly, those currently employed reported better general health and had greater mean values for percent-predicted forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory flow between 25% and 75% of FVC (FEF25-75%) and FEV1/FVC ratio. Among males, females and older age groups, significant differences were observed for almost all the respiratory outcomes for those in current employment. Those in 'Occupations unique to primary industry' had a significantly greater likelihood of regular cough with sputum and ever asthma and had lower mean values of percent-predicted FEV1/FVC and FEF25-75% than those in 'Management occupations'. Those in 'Health occupations' had the highest proportion of current asthma.

CONCLUSIONS

Participants in current employment were healthier than those not in current employment providing further support for the healthy worker effect. Those in 'Occupations unique to primary industry' had an increased risk of adverse respiratory outcomes and reducing workplace exposures in these occupations has the potential to improve their respiratory health.

Workers' recovery from concussions presenting to the emergency department

BACKGROUND

The emergency department (ED) is the first point of care for many patients with concussion, and post-concussion syndrome can impact vocational outcomes like successful return to work. Evaluation of concussion in general adult populations is needed.

AIMS

To document the occurrence and outcomes of work-related concussion presenting to the ED for treatment.

METHODS

This study enrolled adults presenting with concussion to three urban Canadian EDs. Baseline ED interviews, physician questionnaires and patient phone interviews at 30 and 90 days documented work-related events, ED management, discharge advice, patient adherence and symptom severity. Work-related injury and return to work were modelled using logistic or linear regression, as appropriate.

RESULTS

Overall, 172 enrolled workers completed at least one follow-up. Work-related concussions were uncommon (n = 28). Most employees (80%) missed at least 1 day of work (median = 7; interquartile range: 3-14). Most (91%) employees returned to work within 90 days, while 41% reported persistent symptoms. Manual labour and self-reported history of attention deficit hyperactivity disorder were associated with work-related concussion, while days of missed work increased with marital status (divorced), history of sleep disorder and physician's advice to avoid work.

CONCLUSION

Work-related concussions are infrequent; however, most workers who sustain a concussion will miss work, and many return while still experiencing symptoms. Work-related concussion and days of missed work are mainly affected by non-modifiable factors. Workers, employers and the workers' compensation system should take necessary precautions to ensure that workers return to work safely and successfully following a concussion.

Course participation and the recognition and reporting of occupational ill-health

BACKGROUND

The Foundation Course in Occupational Medicine for community-based physicians was started in Alberta in 2012 and has since been implemented across Canada. As part of the evaluation of the first 4 years, two studies were initiated to assess the impact of the course on assessment of work-relatedness and case-reporting.

AIMS

To determine whether assessment of work-relatedness, intention to report cases and number of cases reported to the Workers' Compensation Board (WCB) changed during/after the course.

METHODS

In study 1, course participants were asked to rate scenarios describing ill-health potentially resulting from work. They rated work-relatedness on a visual analogue scale and recorded whether they would report to the WCB. Assessments were made before the course started, after course completion or both. In study 2, numbers of reports to the WCB were documented for physicians giving consent, both for Foundation Course participants and a comparison group of community-based physicians. Multilevel regression models were fitted to allow for potential confounders and clustering within respondent.

RESULTS

Among 102 physicians completing at least one set of scenario assessments, ratings of work-relatedness (β = 6.5; 95% CI 2.6-10.4) and likelihood of reporting to the WCB (OR = 1.9; 95% CI 1.2-3.1) increased significantly post-course. The mean annual number of cases reported to the WCB increased from 91.8 to 125.7 among the 35 Alberta physicians included in study 2. This change was only significant (P < 0.05) on a one-sided test.

CONCLUSION

The two evaluative studies showed good evidence of changes in perceptions and intentions but only weak evidence of behavioural change.

A-29 The Mediating Effects of Personality on Sleep Quality and Executive Dysfunction

Objective

This study examined the relationship between personality traits, sleep quality, and executive dysfunction.

Method

Participants were 195 college students (65.6% female; 53.8% Caucasian, 33.3% African American, 4.1% Asian,; age range 17 – 46 years, Mage = 19.58 years, SD = 3.41; 73.3% no psychological diagnosis) who completed the following attention tasks: 120-item IPIP Neo (NEO), the Pittsburgh Sleep Quality Index (PSQI), and the Barkley Deficits in Executive Functioning Rating Scale-IV (BDEFS-IV).

Results

Mediation analyses were tested using 5000 bootstrapping resamples with bias-corrected 95% confidence estimates to investigate if personality traits mediated the effect of sleep quality on executive dysfunction. The total effect between PSQI and BDEFS-IV was significant, F(1,193) = 15.80, p < .001, r2 = .08, 95% CI = 1.79, 5.31). The model was significant when examining the relationship between the independent variable, mediators, and dependent variable, F(6,188) = 29.31, p < .000, r2 = .48. Three of the five mediators demonstrated significant indirect effects: neuroticism, (B = 1.07, t (188) = 5.39, p = .000, 95% CI = .68, 1.46), extraversion (B = .63, t (188) = 3.46, p = .000, 95% CI = .27, .99), and conscientiousness (B = -1.91, t (188) = -7.46, p = .000, 95% CI = -2.42, -1.41). The direct effect of PSQI and BDEFS-IV was not significant (B = .731, t (188) = .99, p = .32, 95% CI = -.72, 2.18) when controlling for all five mediators, confirming a full mediation.

Conclusions

Neuroticism, Extraversion, and Conscientiousness significantly mediated the relationship between self-reported sleep quality and executive dysfunction.

A-64 The Relationship between Big-5 Personality Factors and Cognitive Health

Objective

The purpose of the current study was to examine the relationship between factors of personality and cognitive health.

Methods

Two hundred and two participants (M age = 19.51, SD = 3.33; M education = 12.40, SD = .75; 72.3% Female, 55.3% White, 36.0% African American, 4.6% Asian, 4.1% Other) completed the cognitive health questionnaire (CHQ) and a 120-item International Personality Item Pool Representation of the NEO-PI-R (IPIP-NEO) as a part of a larger battery in an institutional setting. A CHQ total score was calculated based on items of four positive factors of cognitive health including social/intellectual activities, nutrition, exercise, and eating habits.

Results

A multiple linear regression using backwards elimination was calculated to predict scores on the Cognitive Health Questionnaire utilizing the five personality factors of the IPIP-NEO. The overall five-factor regression model yielded a significant regression equation (F(5,196) = 7.76, p < .001), with an R2 of .165. The final three-factor regression model consisting of extraversion, openness, and consciousness yielded significant results (F(3,198) = 12.70, p < .001), with an R2 of .161.

Conclusions

This exploratory study investigated the relationship between factors of personality and cognitive health. Although a multiple regression model involving all five factors of personality were significantly predictive of cognitive health, the results of this study indicate that greater variance of cognitive health is predicted by extraversion, openness and conscientiousness than neuroticism and agreeableness. Further research should investigate each factor of cognitive health and how these components are predicted by features of personality.

Systematic review: plantar fasciitis and prolonged weight bearing

BACKGROUND

Plantar fasciitis (PF) is one of the most common causes of foot pain. Work can involve factors that may predispose to foot pain.

AIMS

To systematically review the evidence of the association between weight bearing (walking or standing) and PF among workers.

METHODS

Literature search of relevant indexing databases from inception to May 2012, grey literature, websites of relevant organizations and reference lists for all identified articles. Two reviewers independently selected studies for full review, assessed methodological quality and graded evidence. Findings were summarized qualitatively.

RESULTS

Four studies were included; all were assessed as high or unclear risk of bias. Three studies were case-control studies; two used clinic populations and one used volunteers. The other study was cross-sectional involving the workforce of an assembly plant. A number of associations between PF and risk factors were identified including sex, obesity, foot biomechanics and job factors (e.g. job tenure). Two case-control studies and the cross-sectional study found an association with weight bearing, but the assessment of weight bearing varied (e.g. time on feet, time walking or standing). There was low-quality evidence to confirm a causal relationship (Royal College of General Practitioners (RCGP) * grade).

CONCLUSIONS

This systematic review found low-quality evidence of an association between PF and weight-bearing tasks such as walking and standing on hard surfaces. The only occupations specifically identified as having higher risk were those associated with the engine assembly plant. Further research is required to fully determine the association between weight bearing and PF.

Validation study of the Self-Assessment Goal Achievement (SAGA) questionnaire for lower urinary tract symptoms

BACKGROUND

Patients' treatment goals for overactive bladder (OAB) and other lower urinary tract symptoms (LUTS) may not be aligned with their healthcare provider's goals. Successful management of OAB symptoms is improved by individualised treatment plans with attainable treatment goals. Goal attainment setting may facilitate patient-provider interaction and the development of a personalised treatment plan based on realistic, individual goals, thereby increasing patient satisfaction and therapeutic outcomes. The purpose of this study was to validate the utility of the Self-Assessment Goal Achievement (SAGA) questionnaire for LUTS in helping patients identify and achieve realistic treatment goals.

METHODS

The 2-module SAGA questionnaire consists of nine prespecified (fixed) items and five open-ended items for goal identification and ranking (baseline module) and goal achievement rating (follow-up module). Adult patients in the United States (n = 104) seeking treatment for LUTS, including symptoms of OAB, completed the SAGA baseline module, micturition diary, other patient-reported outcome measures (PROs), and discussed their urinary goals with a clinician at baseline. The SAGA follow-up module was completed 2-4 months later. SAGA was validated based on analyses of face, concurrent, known-groups, and convergent validity and item distribution.

RESULTS

Among the nine fixed goals of SAGA, four were ranked as very important by > 50% of patients (i.e. reduce night-time frequency, daytime frequency, urine leakage, urgency). Most patients did not change the importance level of their goals after discussion with their healthcare provider. Pearson correlations between SAGA, diary variables and PRO scores were generally of low to moderate strength. The global mean (SD) follow-up SAGA T-score was 32.54 (12.54), indicating that overall goal attainment was not achieved after 3 months. The goal attainment score was significantly different between groups differing in symptom severity, health-related quality of life, bladder control and continence status.

CONCLUSIONS

The results support the validity of SAGA as a measure of patients' goals and goal achievement for the treatment of LUTS, including symptoms of OAB. SAGA may improve healthcare provider-patient interactions and treatment outcomes in clinical practice.

Mental ill-health and second claims for work-related injury

BACKGROUND

There is some evidence that mental ill-health (MIH) is associated with injury at work, but data are sparse.

AIMS

To examine, within a cohort of workers with a first workers' compensation claim, whether those with a history of MIH had a higher than expected number of second claims.

METHODS

All Workers' Compensation Board (WCB) records from January 1995 to December 2004 were linked to administrative health records, and a physician diagnosis of MIH in the 48 months prior to the first WCB claim extracted. The first and second (if any) claim for each worker were identified and time to second claim calculated. Survival time to second claim was estimated by Cox regression with history of MIH as a covariate.

RESULTS

Results were available for 389 903 WCB first claimants. Of these 53% of men and 38% of women had a second claim, with a mean time between claims of 768 days (men) and 785 days (women). Those with a history of MIH were somewhat more likely to make a second claim and, in the survival analysis, to make this claim sooner. Type of injury at first claim did not appear to modify this effect.

CONCLUSIONS

Workers with a recent history of MIH at the time of making a first WCB claim for a work injury are at greater risk of a second injury, leading to a new claim. Strategies to get workers back to work after the first injury/claim should include management of MIH to reduce the risk of further injury.

How physicians allocate causation: a scenario study with factorial design

BACKGROUND

Causation is a complex concept but important in suspected work-related disease. Physicians routinely make initial assessments of causation as part of their work, but the factors contributing to these assessments are not well understood.

AIMS

To determine which factors influence a family physician's assessment of causation when seeing patients with suspected work-related injury or illness.

METHODS

Four groups of family physicians with differing levels of prior reporting (zero, low, medium, high) to the Workers Compensation Board received a questionnaire including four randomly allocated case scenarios. For each scenario there were four versions with either strong or weak causal features suggesting work or non-work factors were important causes or contributors. Responses to questions were made on a series of visual analogue scales.

RESULTS

The nature of the condition and scenario type (i.e. strength of the causal information about workplace and non-workplace factors) were associated with the physicians' opinion on work-relatedness. Understanding the nature of the patient's work, the timing of symptoms and the patients' opinion about work-relatedness were viewed by the physicians as important. A decision that a condition was not work related was influenced primarily by the strength of potential causes outside work. Prior reporting history of the physician was not associated with opinions on work-relatedness, nor the factors considered in reaching this decision.

CONCLUSIONS

The characteristics of the case scenario were more important in determining a physician's opinion about work-relatedness than the characteristics of the physician.

Mental health in Alberta grain farmers using pesticides over many years

BACKGROUND

Exposure to organophosphates and certain other pesticides has been related to symptoms of mental ill-health. There is particular interest in whether exposure over many years may result in chronic ill-health.

AIMS

To relate lifetime history of pesticide exposure to symptoms and medical records of mental ill-health in elderly grain farmers in Alberta.

METHODS

Two populations of grain farmers were identified for study: cohort A (n = 5986), members of an Alberta farm organization in 1983; cohort B (n = 4781), grain farmers registered with the provincial department of agriculture. In 2002-03 both groups completed a questionnaire on lifetime history of pesticide use, physician diagnosed disease and recent neuropsychological symptoms. Durations of exposure to seven pesticide components were calculated and a factor score extracted from responses to the symptom questionnaire. For a sub-cohort surviving to 2009 medical records for mental ill-health were identified. Records and symptom scores were related to pesticide exposures allowing for confounding.

RESULTS

From cohort A, 1348 and cohort B, 1078 were alive and interviewed (median age 63 years; median duration in farming 40 years): 1371 were linked to the medical records database. Mental ill-health symptom scores were related to duration of exposure to phenoxy compounds (but not to other pesticides) and to mental ill-health in medical records. Those with mental ill-health in hospital discharge records were more likely to have been exposed to phenoxy compounds for ≥35 years.

CONCLUSIONS

The relationship of long-term exposure to phenoxy herbicides and neuropsychiatric symptoms was unexpected but not explained by measured confounders.

Physician diagnosed mental ill-health in male and female workers

BACKGROUND

Although there have been many studies of work demands and self-reported job strain, few have examined incident physician-diagnosed mental ill-health (MIH) by detailed occupational group.

AIMS

To investigate whether linkage of occupation from worker compensation claims to diagnoses from administrative health records can give credible information on occupation and incidence of MIH by diagnostic group and gender.

METHODS

Information on occupation from all worker compensation claims 1995-2004 in Alberta, Canada were linked to administrative health records of MIH diagnoses. Relative risks for affective, substance use and psychotic disorders by four digit occupational codes were calculated for men and women aged 18-65 years in a log-binomial regression adjusting for age and stratifying by sex.

RESULTS

There were 327883 male and 88483 female compensation claims available for the analysis of incident cases. Affective disorders (5.2% men, 11.5% women) were much more common than substance use disorders or psychotic disorders (both ≤1%) in this population of working people. In men, the type of work appeared to either protect from or precipitate affective disorders, but no protective effect was seen for women. Substance use disorders clustered mainly in physically demanding occupations typically involving employment outside the urban areas. New onset psychotic disease was rare but seen in excess in painters, boilermakers and chefs.

CONCLUSIONS

Data linkage of occupation close to the time of new onset MIH can provide important insight into the relation between work and physician-diagnosed MIH and indicate areas in which intervention might be appropriate.

Using a symptom diary to investigate work-related urticaria

BACKGROUND

The strategy of keeping a diary may not be considered by many treating clinicians, but this approach has been recommended for occupational asthma and proved useful in this case of chronic urticaria associated with work.

AIMS

To report a case of a health care worker who had significant allergic reactions that were found to be associated with exposure to test allergens while working in an asthma clinic.

METHODS

The patient, a nurse working in a paediatric asthma clinic, was known to be allergic to common allergens that were used to test patients in the clinic. She developed reactions including swelling of the eyelids and urticarial reactions on the forehead, torso and upper and lower limbs on different occasions. A symptom diary was used to collect information on the reactions and the activity performed at the time they occurred.

RESULTS

She recorded symptoms that were mainly urticarial, with additional rhinitis or wheeze on occasion, on 20 (74%) working days and only 5 (28%) non-work days, indicating a significant association (P < 0.01) between her symptoms and working days.

CONCLUSIONS

Medical management had not controlled her symptoms, which improved on removal from the work activity and was confirmed by further diary recording.

Explaining Alberta's rising mesothelioma rates

Although mesothelioma rates have been rising worldwide, little is known about mesothelioma trends in Alberta. This population-based descriptive study used Alberta Cancer Board Registry data from 1980 to 2004 to develop an age-period-cohort model of male pleural mesothelioma incidence rates over time. Both age and cohort effects are associated with incidence rates. The highest-risk cohort comprised men born between 1930 and 1939, reflecting widespread asbestos use and exposure beginning in the 1940s in Canada. We predict that 1393 Albertan men 40 years and older will die of pleural mesothelioma between 1980 and 2024; 783 (56.2%) of these deaths will occur between 2010 and 2024. The total number of mesothelioma deaths in Alberta will be higher when all age groups, both sexes, and all disease sites are included, with numbers likely peaking sometime between 2015 and 2019. In addition to the ongoing efforts that focus on eliminating asbestos-related disease in Alberta, the challenge is to implement surveillance systems to prevent future epidemics of preventable occupational cancers in Alberta.

Quantification of 2,4-D on Solid-Phase Exposure Sampling Media by LC-MS-MS

Three types of solid-phase chemical exposure sampling media: cellulose, polyurethane foam, and XAD-2, were analyzed for 2,4-dichlorophenoxyacetic acid (2,4-D) and the amine salts of 2,4-D. Individual samples were extracted into acidified methanol, and the extracts were analyzed via liquid chromatography-tandem mass spectrometry using electrospray ionization and a C(8) reversed-phase LC column. (13)C 2,4-D and a labeled benzoic acid (13)C or d5) were employed as the surrogate and internal standard, respectively. Over a three-year study of pesticide exposure among agricultural workers involving a high volume of analyses, values of average % recovery for (13)C 2,4-D on personal exposure samples ranged from 87 to 98 with a % relative standard deviation ranging from 7 to 12. The performance of the method compares favorably with that of the current National Institute for Occupational Safety and Health-recommended approach for the analysis of 2,4-D on these types of exposure sampling matrices.

Continuing professional development of occupational medicine practitioners: a needs assessment

OBJECTIVE

The aim of this study was to identify elements of occupational medicine practice used on a frequent basis which are considered to be of high priority for continuing professional development (CPD).

METHODS

A postal questionnaire covering 28 areas of knowledge or practice was sent to all members of the Society of Occupational Medicine in September 2000. Respondents were asked to allocate scores to the 28 items for both CPD priority and frequency of use.

RESULTS

The return rate for questionnaires was 29.5%. There was reasonable agreement between frequency of use and CPD priority ratings for the elements covered in the questionnaire.

CONCLUSIONS

Despite the low return rate for questionnaires, this survey has helped identify themes which are important to physicians practising occupational medicine and has also highlighted those which are less important for inclusion in a CPD programme. Some differences in responses were identified between accredited specialists, specialist registrars and non-specialist practitioners of occupational medicine. The findings from this survey should be useful to providers of continuing medical education in planning courses, study days and electronic or distance learning educational packages.

Implementation of statutory occupational respiratory health surveillance

Health surveillance is required by UK regulations in certain circumstances, and is usually provided through an occupational health organization. Although there are studies assessing the provision of health surveillance across the country, there are no published studies addressing the practical application of legislation, guidelines and medical research to respiratory health surveillance programmes. An audit of a multidisciplinary health surveillance programme was carried out, using review of occupational health records, occupational hygiene reports and managers' risk assessments, to compare the implementation of health surveillance in different organizations and under different contractual relationships. Sixty-six per cent of National Health Service (NHS) and 56% of industrial workplaces were able to provide risk assessments but were unable to link these with appropriate health surveillance. Twenty-seven per cent of NHS employees potentially exposed to respiratory sensitizers had baseline surveillance, compared with 87% in industry. Fifty-five per cent of Medical Research Council questionnaires were inappropriately administered by the employee themselves, rather than an interviewer as recommended. Other follow-up questionnaires in use had not been formally validated. Non-regular lung function assessment using spirometry was the predominant tool used for follow-up surveillance. There was no overall strategic approach to respiratory health surveillance in the organization studied. Health surveillance programmes should focus on disease prevention without becoming a repetitious application of unvalidated tools. Clinical governance demands quality assurance standards that will effectively implement a coordinated approach to health surveillance.

Longitudinal analyses of chest radiographs from the European Carbon Black Respiratory Morbidity Study

High levels of exposure to carbon black have been linked with an increased prevalence of chest radiograph abnormalities. However, it is unclear to what extent current levels of exposure in the carbon black manufacturing industry are associated with new cases of and progression in small opacities. Longitudinal analyses were carried out on data from workers in the European carbon black manufacturing industry who provided three full-size chest radiographs sequentially between 1987-1995. All chest radiographs were independently read by three experienced readers according to the International Labour Organisation (ILO) classification. After exclusion of participants with previous lung diseases or injuries, females, unreadable chest radiographs and from factories with a low participation rate, data from 675 workers were available for the longitudinal analyses. An association was observed between cumulative carbon black exposure and new cases of chest radiograph abnormalities (ILO category > or = 1/0) and progression in small opacities. These associations were mainly related to changes in chest radiographs from workers at one factory. A large percentage of workers with chest radiograph abnormalities reversed to normal chest films; however, after adjusting for other factors, this was not associated with levels of exposure to carbon black dust. In conclusion, the results show that exposure to carbon black is associated with increased risk of chest radiographic abnormalities, which may be reversible after reduction or cessation of exposure.

Dichlorodiphenyldichloroethene, polychlorinated biphenyls, and breast cancer among African-American and white women in North Carolina

We examined plasma dichlorodiphenyldichloroethene (DDE) and total polychlorinated biphenyl (PCB) levels in relation to breast cancer in a population-based, case-control study of African-American women (292 cases and 270 controls) and white women (456 cases and 389 controls) in North Carolina. Adjusted odds ratios (ORs) for breast cancer comparing the highest to lowest third of DDE were 1.41 [95% confidence interval (CI), 0.87-2.29] in African-American women and 0.98 (95% CI, 0.67-1.43) in white women. ORs comparing the highest to lowest third of total PCBs were 1.74 (95% CI, 1.00-3.01) in African-American women and 1.03 (95% CI, 0.68-1.56) in white women. Among African-Americans, the OR for total PCBs was highest for obese women (body mass index 234.2; OR, 4.92; 95% CI, 1.63-14.83). In contrast, the OR for DDE was highest for the leanest African-American women (body mass index, <25; OR, 3.84; 95% CI, 0.98-15.08). ORs for DDE were not elevated among women who lived or worked on farms or elevated among farming women who reported exposure to pesticides. Our results suggest absence of a strong effect for DDE or total PCBs in breast cancer but lend support for associations among subgroups of women. In our study, factors such as income, parity, breastfeeding, race/ethnicity, and body mass index influenced the relationship of organochlorines and breast cancer. Differing distributions of such factors may explain some of the inconsistencies across previous studies.

Chemical and mutagenic properties of asphalt fume condensates generated under laboratory and field conditions

Exposure to asphalt fumes is widely recognized as a potential occupational health concern for paving and roofing workers. Two studies suggest that asphalt fumes generated in the laboratory are carcinogenic to mice. In this study, asphalt fume condensate (AFC) was collected from the head space of an operating hot mix asphalt storage tank and from a laboratory fume-generating apparatus operating at approximately 149 degrees C and 316 degrees C. Salmonella assays for mutagenesis, in vitro chromosomal aberration assays using Chinese hamster ovary (CHO) cells, chemical analyses, and simulated distillations were performed using gas chromatography to characterize the toxicological and chemical properties of AFCs generated by these two methods. The 316 degrees C lab AFC sample was more mutagenic in the Salmonella assay than the 149 degrees C lab AFC sample, with mutagenicity indices (MIs) of 8.3 and 5.3, respectively. AFCs collected from the storage tank were not mutagenic. Chromosomal aberration assays of all AFCs were negative. Chemical analyses and simulated distillations showed substantial differences in the chemical composition of the AFC samples. The 316 degrees C lab AFC sample contained more higher-boiling-point (three- and four-ring) polycyclic aromatic sulfur heterocycle compounds than the 149 degrees C lab AFC sample, and both lab AFC samples contained 5 to 100 times more of these compounds than AFC samples collected from the asphalt storage tank. These results are consistent with other data reported in the scientific literature describing the carcinogenicity of higher-boiling-point sulfur heterocycle compounds. In contrast to other recent studies, the results of this study indicate that the chemical composition and toxicological properties of laboratory-generated asphalt fumes are not representative of those properties of fumes to which workers and the public might be exposed.

Four-year changes in college athletes' ethical value choices in sports situations

Positive values for fairness in competition are supposed to undergird the behavior of athletes engaged in sport. Whether athletes' values actually develop over 4 years in a college that emphasizes character development is the focus of this study. Athletes' (N = 631) use of deontological ethics (Hahm, Beller & Stoll, 1989) in 21 sports value dilemmas were evaluated. At entrance, as well as near graduation, intercollegiate athletes' value scores were lower than intramural athletes' scores. Both groups' scores declined while they were in college. Individual-sport athletes had higher scores than team-sport athletes but manifested a greater decline over 4 years. The findings are consistent with other studies that show decreases in "sportsmanship orientation" and an increase in "professional" attitudes associated with participation in sport.

Respiratory symptoms and lung function in two prebake aluminum smelters

BACKGROUND

Respiratory symptoms are known to occur in some aluminum smelter employees working in the potroom department but little is known about the respiratory health of employees in other departments.

METHODS

This cross-sectional study examined the prevalence of work-related respiratory symptoms and levels of lung function in different departments of two aluminum smelters compared to administration employees. Multiple logistic regression was performed with each of four work-related symptoms as outcomes and multiple linear regressions were performed with FEV1 and FVC as outcomes.

RESULTS

There were 1,529 male participants in the two smelters representing a response rate of 89.6%. After adjusting for age and smoking, work-related respiratory symptoms were reported significantly more often among the ingot mill, anode, and potroom groups in Smelter A. In Smelter B, ingot employees were more likely to report work-related wheeze and potroom employees were more likely to report work-related rhinitis. Symptoms tended to increase with increasing time in the potrooms but were more likely to occur in new employees in the ingot mill and anode process groups. After adjusting for age, height, and smoking, there were no significant differences between the process groups for either FEV1 or FVC at Smelter A, and at Smelter B potroom employees had slightly greater FEV1 and FVC than the administration employees.

CONCLUSIONS

Work-related respiratory symptoms among aluminum smelter workers are not reported only by potroom employees but also by ingot mill and anode employees.

The G209A mutation in the alpha-synuclein gene is not detected in familial cases of Parkinson disease in non-Greek and/or Italian populations

OBJECTIVE

To determine whether the G-to-A substitution at nucleotide 209 (G209A) mutation in the alpha-synuclein gene is responsible for familial Parkinson disease (PD) in the US population.

DESIGN

Polymerase chain reaction-based DNA analysis of consecutive patients with PD and family history of PD.

SETTING

A university-affiliated movement disorder clinic and a Veterans Affairs clinical research laboratory.

PATIENTS

Forty-four patients with PD and family history of PD and 29 patients with sporadic PD, all with no known Greek and/or Italian background.

RESULTS

None of the DNA samples showed the G209A mutation.

CONCLUSION

The G209A mutation is rare in US patients with familial PD.

Distinct roles for LFA-1 and CD28 during activation of naive T cells: adhesion versus costimulation

Efficient T cell activation requires the engagement of a variety of ligand/receptor molecules in addition to T cell receptor (TCR)-major histocompatibility complex (MHC)/peptide interactions. The leukocyte function antigen 1 (LFA-1) and the CD28 glycoprotein have both been implicated in T cell activation. The present study dissects the roles of LFA-1 and CD28 in the activation of naive virus-specific CD8+ T cells. We demonstrate that LFA-1 facilitates T cell activation by lowering the amounts of antigen necessary for T cell activation. In the absence of LFA-1, 100-fold more antigen was required for T cell-antigen-presenting cell (APC) conjugation and all subsequent events of T cell activation, including TCR down-regulation, Ca2+-flux, T cell proliferation, and lytic effector cell induction. Thus, LFA-1 facilitates the functional triggering of TCRs by promoting adhesion of T cells to APCs but does not affect T cell activation otherwise. In contrast, CD28 played an entirely different role during T cell activation. CD28 reduced the number of TCRs that had to be triggered for T cell activation and allowed activation of T cells by low affinity ligands. CD28 but not LFA-1 prevented induction of T cell unresponsiveness after stimulation of TCRs. These results demonstrate that LFA-1 and CD28 exhibit distinct, nonoverlapping ways to influence T cell activation and suggest that the terms costimulation and signal 2 should be revisited.