Chlorinated hydrocarbon solvents: Substituting our way toward human carcinogenicity

A discussion of the history of substitutions in industrial solvent use is presented, and animal carcinogenicity studies with certain chlorinated hydrocarbon solvents are reviewed. The present knowledge on the association between occupational exposure to chlorinated hydrocarbon solvents and human carcinogenicity is summarized, including a critical review of 23 studies pertaining to human carcinogenicity. Several deficiencies are identified in these studies that make interpretation of the results uncertain, including poor characterization of exposures in qualitative and quantitative terms, the small numbers of deaths or cases, and short follow-up periods. Despite these weaknesses, we conclude that, when viewed collectively, the evidence strongly suggests that occupational exposures to chlorinated hydrocarbon solvents are associated with an excess human cancer risk. The literature supports an association between occupational exposures to chlorinated hydrocarbons and elevated risks of leukemia, lymphoma, and urinary tract cancer. Parental occupational exposures are consistently associated with an elevated childhood cancer risk in the offspring. © 1993 Wiley-Liss, Inc.     

Early life patterns of common infection: a latent class analysis

Early life infection has been implicated in the aetiology of many chronic diseases, most often through proxy measures. Data on ten infectious symptoms were collected by parental questionnaire when children were 6 months old as part of the Avon Longitudinal Study of Parents and Children, United Kingdom. A latent class analysis was used to identify patterns of infection and their relationship to five factors commonly used as proxies: sex, other children in the home, maternal smoking, breastfeeding and maternal education. A total of 10,032 singleton children were included in the analysis. Five classes were identified with differing infectious disease patterns and children were assigned to the class for which they had a highest probability of membership based on their infectious symptom profile: ‘general infection’ (n = 1,252, 12.5%), ‘gastrointestinal’ (n = 1,902, 19.0%), ‘mild respiratory’ (n = 3,560, 35.5%), ‘colds/ear ache’ (n = 462, 4.6%) and ‘healthy’ (n = 2,856, 28.5%). Females had a reduced risk of being in all infectious classes, other children in the home were associated with an increased risk of being in the ‘general infection’, ‘mild respiratory’ or ‘colds/ear ache’ class. Breastfeeding reduced the risk of being in the ‘general infection’ and ‘gastrointestinal’ classes whereas maternal smoking increased the risk of membership. Higher maternal education was associated with an increased risk of being in the ‘mild respiratory’ group. Other children in the home had the greatest association with infectious class membership. Latent class analysis provided a flexible method of investigating the relationship between multiple symptoms and demographic and lifestyle factors.     

Occupational exposure to chemicals and risk of thyroid cancer in Sweden

Purpose  To explore thyroid cancer (TC) risk in the Swedish population, associated with occupational exposure to certain chemicals. Methods  National cancer and death registries were used to follow-up (1971–1989) all Swedish workers employed in the 1970 census. Each combination of occupation and industry was linked to a Swedish job-exposure matrix (JEM), with exposure to 13 chemicals classified as “possible exposure”, “probable exposure” or “unexposed”. Relative risks were obtained using Poisson models adjusted for age, period and geographical area. A second analysis was performed, in which adjustment was additionally made for simultaneous exposure to other matrix chemicals and ionising radiations. Results  Probable exposure to solvents among women displayed an increased risk (RR = 1.91; 95%CI:1.05–3.45), mainly due to a higher risk observed among shoe-cutters, lasters and sewers engaged in shoe-making. Conclusions  Exposure to solvents, used mainly in the shoe and leather industry, seems to be associated with excess TC among women.     

Occupational Exposure to Solvents and Risk of Non-Hodgkin Lymphoma in Connecticut Women

A population-based case-control study involving 601 incidentcases of non-Hodgkin lymphoma (NHL) and 717 controls was conductedin 1996–2000 among Connecticut women to examine associationswith exposure to organic solvents. A job-exposure matrix wasused to assess occupational exposures. Increased risk of NHLwas associated with occupational exposure to chlorinated solvents(odds ratio (OR) = 1.4, 95% confidence interval (CI): 1.1, 1.8)and carbon tetrachloride (OR = 2.3, 95% CI: 1.3, 4.0). Thoseever exposed to any organic solvent in work settings had a borderlineincreased risk of NHL (OR = 1.3, 95% CI: 1.0, 1.6); moreover,a significantly increased risk was observed for those with averageprobability of exposure to any organic solvent at medium-highlevel (OR = 1.5, 95% CI: 1.1, 1.9). A borderline increased riskwas also found for ever exposure to formaldehyde (OR = 1.3,95% CI: 1.0, 1.7) in work settings. Risk of NHL increased withincreasing average intensity (P = 0.01), average probability(P < 0.01), cumulative intensity (P = 0.01), and cumulativeprobability (P < 0.01) level of organic solvent and withaverage probability level (P = 0.02) and cumulative intensitylevel of chlorinated solvent (P = 0.02). Analyses by NHL subtypeshowed a risk pattern for diffuse large B-cell lymphoma similarto that for overall NHL, with stronger evidence of an associationwith benzene exposure. Results suggest an increased risk ofNHL associated with occupational exposure to organic solventsfor women. case-control studies; lymphoma, non-Hodgkin; risk factors; solvents     

The CASP-19 as a measure of quality of life in old age: evaluation of its use in a retirement community

Purpose  

The CASP-19 is a quality-of-life measure comprising four domains (‘control’, ‘autonomy’, ‘pleasure’ and ‘self-realization’), developed initially in a population aged 65–75 years. This study tested the scale for use in a population whose demographic profile and residential status differed markedly from the original population.     

Conceptualising Health: Insights from the Capability Approach

This paper suggests the adoption of a ‘capability approach’ to key concepts in healthcare. Recent developments in theoretical approaches to concepts such as ‘health’ and ‘disease’ are discussed, and a trend identified of thinking of health as a matter of having the capability to cope with life’s demands. This approach is contrasted with the WHO definition of health and Boorse’s biostatistical account. We outline the ‘capability approach’, which has become standard in development ethics and economics, and show how existing work in those areas can profitably be adapted to healthcare. Cases are used to illustrate the value of adopting a capability approach.

Emotions generated by food in elderly French people

Eating behaviour depends partly on food preference, which may be determined by different types of emotions. Among the emotions generated by food, disgust and pleasure are common and can lead to increased and reduced food consumption. We tested the hypothesis that (1) elderly men and women felt different emotions towards food, and (2) low energy intake is related to negative emotions towards food. In February 2004, a convenience sample of elderly participants was recruited locally by telephone. Food intake of 52 elderly people, aged 63–80 years, was monitored throughout each day for one week and made it possible to assign the elderly people to two groups (low and high energy intake from food consumption data). One month later, each of them assessed their likes or dislikes towards 30 food pictures (vegetables, cheeses, fruits, starchy foods, sweets, meat, fish, offal and eggs) using 19 emotional words (eight words with a positive valence: ‘to like’, ‘thrilled’, ‘satisfaction’, ‘surprise’, ‘serene’, ‘amused’, ‘pride’, ‘interest’, and 11 other words with a negative valence: ‘disgust’, ‘indifference’, ‘guilt’, ‘uneasiness’, ‘nostalgia’, ‘impatience’, ‘doubt’, ‘frustration’, ‘embarrassment’, ‘disappointment’ and ‘lassitude’. The emotional intensities experienced with the different pictures were analysed by ANOVA for each group (men and women, small and big eaters). There were differences in likes and dislikes between men and women. Both guilty and liking scores towards food were generally higher in women than in men. Small eaters felt more doubt, unease, disappointment and indifference towards food than big eaters. In conclusion, the report of low food intake was related to more negative emotions towards foods that might be associated with the willingness to restrict food intake or to undernutrition.     

Occupational risk factors for urothelial carcinoma: agent-specific results from a case-control study in Germany. MURC Study Group. Multicenter Urothelial and Renal Cancer

BACKGROUND: This multicentre population-based case-control study was conducted to estimate the urothelial cancer risk for occupational exposure to aromatic amines, polycyclic aromatic hydrocarbons (PAH), and chlorinated hydrocarbons besides other suspected risk factors. METHODS: In a population-based multicentre study, 1035 incident urothelial cancer cases and 4298 controls matched for region, sex, and age were interviewed between 1991 and 1995 for their occupational history and lifestyle habits. Exposure to the agents under study was self-assessed as well as expert-rated with two job-exposure matrices and a job task-exposure matrix. Conditional logistic regression was used to calculate smoking adjusted odds ratios (OR) and to control for study centre and age. RESULTS: Urothelial cancer risk following exposure to aromatic amines was only slightly elevated. Among males, substantial exposures to PAH as well as to chlorinated solvents and their corresponding occupational settings were associated with significantly elevated risks after adjustment for smoking (PAH exposure, assessed with a job-exposure matrix: OR = 1.6, 95% CI: 1.1-2.3, exposure to chlorinated solvents, assessed with a job task-exposure matrix: OR = 1.8, 95% CI: 1.2-2.6). Metal degreasing showed an elevated urothelial cancer risk among males (OR = 2.3, 95% CI: 1.4-3.8). In females also, exposure to chlorinated solvents indicated a urothelial cancer risk. Because of small numbers the risk evaluation for females should be treated with caution. CONCLUSIONS: Occupational exposure to aromatic amines could not be shown to be as strong a risk factor for urothelial carcinomas as in the past. A possible explanation for this finding is the reduction in exposure over the last 50 years. Our results strengthen the evidence that PAH may have a carcinogenic potential for the urothelium. Furthermore, our results indicate a urothelial cancer risk for the use of chlorinated solvents.     

Job Satisfaction and the Work Situation of Physicians: a survey at a German University hospital

Summary. Objective: Job demands and workload of hospital physicians are increasing. The object of this survey was to examine the factors that constitute job satisfaction and to analyse physicians’ work situation in the area of in-patient care. Methodology: 447 physicians at a German University Hospital received questionnaires with regard to work situation, job satisfaction and personal health. Data were analysed by MANOVA and multiple regression models. Results: A first regression model explained 53% of the variance in satisfaction with ‘work and profession’. Among the explanatory variables ‘superiors and hierarchy’ showed the highest beta-weight (β = −0.49). ‘Personal health’ also determined job satisfaction, for female physicians stronger (β = −0.31) than for male physicians (β = −0.11). In a second regression model on satisfaction with ‘Financial situation’ only 18% of the variance was explained, whereby ‘work condition on the ward’, ‘personal health’ and ‘collaboration between occupational groups’ showed the highest beta-weights. Discussion: Among resident physicians, work conditions, superiors, hierarchy, transparency and participation in decisions are very important variables for job satisfaction. Improvements in these aspects may improve job satisfaction and help to reduce physician shortage in hospitals. Submitted: 2 March 2005; Revised: 31 May, 29 August 2005, 15 November 2005; Accepted: 9 June 2006     

Systemic sclerosis and occupational risk factors: a case-control study

Aims: A case–control study was carried out between 1998 and 2000 to investigate the relation between systemic sclerosis and occupational exposure.

Methods: Eighty cases of systemic sclerosis admitted consecutively to the Department of Internal Medicine at the University Hospital of Tours from 1998 to 2000 were included. For each case, two age, gender, and smoking habits matched controls hospitalised during the same period in the same department were selected. A committee of experts was set up retrospectively to assess occupational exposure. Exposure to silica dust and organic solvents (such as trichlorethylene and other chlorinated solvents, and benzene and other aromatic solvents) was investigated using semiquantitative estimates of exposure. An exposure score was calculated for each subject based on probability, intensity, daily frequency, and duration of exposure for each period of employment. The final cumulative exposure score was obtained, taking into account all periods of employment.

Results: Significant associations with SS were observed for crystalline silica, trichlorethylene, chlorinated solvents, toluene, aromatic solvents, ketones, white spirit, epoxy resins, and welding fumes. Risk of SS was significantly associated with a high final cumulative exposure score of occupational exposure to crystalline silica, trichlorethylene, chlorinated solvents, welding fumes, and any types of solvents.

Conclusion: Results confirm the influence of occupational risk factors in the occurrence of SS in both men and women. The link is not only with silica but also with other compounds such as solvents.

     

Validation of a Risk Factor-Based Intervention Strategy Model Using Data from the Readiness for Return to Work Cohort Study

Background Low back pain (LBP) is a common and in some cases disabling condition. Until recently, workers presenting with non-specific LBP have generally been regarded as a homogeneous population. If this population is not homogeneous, different interventions might be appropriate for different subgroups. We hypothesized that (1) Clusters of individuals could be identified based on risk factors, (2) These clusters would predict duration and recurrences 6 months post-injury. Methods The study focuses on the 442 LBP claimants in the Readiness for Return-to-Work Cohort Study. Claimants (n = 259) who had already returned to work, approximately 1 month post-injury were categorized as the low risk group. A latent class analysis was performed on 183 workers absent from work, categorized as the high risk group. Groups were classified based on: pain, disability, fear avoidance beliefs, physical demands, people-oriented culture and disability management practice at the workplace, and depressive symptoms. Results Three classes were identified; (1) workers with ‘workplace issues’, (2) workers with a ‘no workplace issues, but back pain’, and (3) workers having ‘multiple issues’ (the most negative values on every scale, notably depressive symptoms). Classes 2 and 3 had a similar rate of return to work, both worse than the rate of class 1. Return-to-work status and recurrences at 6 months were similar in all 3 groups. Conclusion This study largely confirms that several subgroups could be identified based on previously defined risk factors as suggested by an earlier theoretical model by Shaw et al. (J Occup Rehab 16(4):591–605, 2006). Different groups of workers might be identified and might benefit from different interventions.     

Occupational exposure to hydrocarbons and chronic pancreatitis: a case-referent study.

OBJECTIVES--To investigate the hypothesis that hydrocarbon exposure is a risk factor for chronic pancreatitis. METHODS--102 cases of chronic pancreatitis and 204 age and sex matched referents were interviewed about their occupational histories, alcohol and cigarette consumption, and diet. Exposure to hydrocarbons was inferred from interview responses by four assessors who were blind to disease state, and these data were then summarised by a cumulative hydrocarbon exposure (CHE) score. RESULTS--After adjustment for alcohol, cigarettes, dietary antioxidants, and social class, odds ratios for low CHE scores were 1.20 (90% CI: 0.62-2.35) and 2.67 (90% CI: 1.22-5.87) for high scores. A test for trend with level of exposure among only those who had exposure scores > 0 gave p = 0.09. Analysis by type of hydrocarbon was limited to four exposures for each of which there were at least 20 exposed patients. The adjusted OR for paint solvents (any level) was 0.96 (90% CI: 0.48-1.93); for diesel exhaust fumes OR = 2.66 (90% CI: 1.05-6.73); for petrochemicals OR = 1.82 (90% CI: 0.80-4.11); and for chlorinated solvents OR = 1.49 (90% CI: 0.58-3.81). CONCLUSIONS--These results support the original hypothesis. Further studies are needed to confirm or refute the findings here and to clarify the types of hydrocarbon involved.     

Outdoor work and skin cancer incidence: a registry-based study in Bavaria

Objective  To analyse the association between occupational ultraviolet (UV) light exposure and skin cancer (basal cell carcinoma, BCC; squamous cell carcinoma, SCC; cutaneous malignant melanoma, CMM) based on data from the Bavarian population-based cancer registry. Methods  The population-based cancer registry of Bavaria (Germany) provided data on incident cases of BCC, SCC, and CMM, respectively, during the period 2001 until 2005. Eleven Bavarian districts with complete skin cancer registration were included in this analysis based on 2,156,336 person years. Cases were assigned to “indoor”, “mixed indoor/outdoor”, and “outdoor” exposure categories according to their job title. We computed age-specific and age-adjusted incidence rates of BCC (n = 1,641), SCC (n = 499), and CMM (n = 454) by work type, and the relative risk (RR) of skin cancer occurrence for “outdoor” and “mixed indoor/outdoor” workers, respectively, compared to “indoor” workers. Results  The risk of BCC was substantially elevated in male (RR, 2.9; 95% CI, 2.2–3.9) and female (RR, 2.7; 95% CI, 1.8–4.1) outdoor workers compared to male and female indoor workers, respectively. We also found an elevated risk of similar magnitude for SCC in male (RR, 2.5; 95% CI, 1.4–4.7) and female (RR, 3.6; 95% CI, 1.6–8.1) outdoor workers compared to male and female indoor workers, respectively. CMM risk was not significantly associated with outdoor work. Conclusion  Our study confirms previous reports on the increased risk of BCC and SCC in outdoor workers compared to indoor workers.     

Simultaneous trend analysis for evaluating outcomes in patient-centred health monitoring services

The research aim underpinning the Healthcare@Home (HH) information system described here was to enable ‘near real time’ risk analysis for disease early detection and prevention. To this end, we are implementing a family of prototype web services to ‘push’ or ‘pull’ individual’s health-related data via an system of clinical hubs, mobile communication devices and/or dedicated home-based network computers. We are examining more efficient methods for ethical use of such data in timeline-based (i.e. ‘longitudinal’) data analysis systems. A consistent data collation infrastructure is being created for use along the ‘patient path’—accessible wherever patients happen to be. This ‘patient-centred’ infrastructure can be applied in the evaluation of disease progression risk (in the light of clinical understanding of disease processes). In this paper we describe the requirements for making multi-data trend management ‘scale-up’, together with some requirements of an ‘end-to-end’ functioning data collection system. A Service-Oriented Architecture (SOA) approach is used to maximise benefits from (1) clinical evidence and (2) computational models of disease progression that can be made available elsewhere on the SOA. We discuss the implications of this so-called ‘closed loop’ approach for improving healthcare intervention outcomes, patient safety, decision support, objective measurement of service quality and in providing inputs for quantitative healthcare (predictive) modelling. To aid understanding, a concise glossary is provided for italicized technical or common ‘jargon’ terms that are not defined in the text.     

Occupational exposures and pancreatic cancer: a meta-analysis

OBJECTIVES—Consolidation of epidemiological data on pancreatic cancer and worksite exposures.
METHODS—Publications during 1969-98 were surveyed. Studies without verified exposures were excluded. Meta-analyses were conducted on data from 92 studies covering 161 populations, with results for 23 agents or groups of agents. With a standard format, five epidemiologists extracted risk estimates and variables of the structure and quality of each study. The extracted data were centrally checked. Random meta-models were applied.
RESULTS—Based on 20 populations, exposure to chlorinated hydrocarbon (CHC) solvents and related compounds was associated with a meta-risk ratio (MRR) of 1.4 (95% confidence interval (95% CI) 1.0 to 1.8). Nickel and nickel compounds were considered in four populations (1.9; 1.2 to 3.2). Excesses were found also for chromium and chromium compounds (1.4; 0.9 to 2.3), polycyclic aromatic hydrocarbons (PAHs) (1.5; 0.9 to 2.5), organochlorine insecticides (1.5; 0.6 to 3.7), silica dust (1.4; 0.9 to 2.0), and aliphatic and alicyclic hydrocarbon solvents (1.3; 0.8 to 2.8). Evidence on pancreatic carcinogenicity was weak or non-positive for the following agents: acrylonitrile (1.1; 0.0 to 6.2); arsenic (1.0; 0.6 to 1.5); asbestos (1.1; 0.9 to 1.5); diesel engine exhaust (1.0; 0.9 to 1.3); electromagnetic fields (1.1; 0.8 to 1.4); formaldehyde (0.8; 0.5 to 1.0); flour dust (1.1; 0.3 to 3.2); cadmium and cadmium compounds (0.7; 0.4 to 1.4); gasoline (1.0; 0.8 to 1.2); herbicides (1.0; 0.8 to 1.3); iron and iron compounds (1.3; 0.7 to 2.5); lead and lead compounds (1.1; 0.8 to 1.5); man-made vitreous fibres (1.0; 0.6 to 1.6); oil mist (0.9; 0.8 to 1.0); and wood dust (1.1; 0.9 to 2.5). The occupational aetiological fraction of pancreatic cancer was estimated at 12%. In a subpopulation exposed to CHC solvents and related compounds, it was 29%; to chromium and chromium compounds, 23%; to nickel and nickel compounds, 47%; to insecticides, 33%; and to PAHs, 33%.
CONCLUSION—Occupational exposures may increase risk of pancreatic cancer. High quality studies are called for on interactions between occupational, environmental, and lifestyle factors as well as interactions between genes and the environment.


Keywords: pancreatic cancer; occupational exposure; meta-analysis     

Time trends in occupational exposure to chemicals in Sweden: proportion exposed,distribution across demographic and labor market strata,and exposure levels

ObjectiveThis study investigated time trends in occupational exposure to various chemicals in Sweden and the distribution across demographic and labor market sectors.MethodsExposure to six chemicals was investigated from 1980 to 2013 by application of a job exposure matrix to national population registers. Respirable crystalline silica (RCS), diesel engine exhaust, welding fumes, wood dust, chlorinated hydrocarbon solvents, and lead were selected to represent different groups of chemicals. Trends in exposure prevalence were investigated by linear regression and compared to the occupationally active population. Confidence intervals for the rate of change over time were obtained by bootstrapping.ResultsThe proportion of workers born outside the Nordic countries increased over time in those exposed to RCS, diesel exhaust and wood dust. There was a shift of exposed jobs to small companies (<50 employees), especially for RCS, welding fumes, wood dust, and chlorinated hydrocarbon solvents. For RCS and welding fumes, there was a marked drop in exposure levels from 1980 to 1990 but small changes thereafter. Exposure to lead diminished, both in terms of prevalence and intensity.ConclusionsOver time, several exposures tended to shift to small companies, the construction sector, and migrant workers, all factors being indicative of less well-controlled working conditions. Occupational exposure to chlorinated organic solvents and lead diminished, while exposure levels to RCS and welding fumes have changed little since 1990. In view of the serious and well-established negative health effects, increased efforts to reduce exposure to RCS and welding fumes are needed.     

Attending to audience: comparing optometry student talk with and about patients

We explored mediating concepts that affect clinical novices shifting between their talk with patients in eye examinations and their talk about patients in case presentations (nCPs). In a Canadian optometry teaching clinic, patient ‘chief concern or request’, ‘illness experience’, and ‘management’ utterances were observed in ten eye examinations and nCPs. Twenty-three participants (8 students, 5 instructors, and 10 patients) were observed; 22 were subsequently interviewed. Of 10 nCPs, the ‘chief concern or request’ was absent in four, the ‘illness experience’ was incomplete or absent in 9 and 5 of 19 (35.7%) ‘management’ topics were not discussed with patients. During eye exams, 17 of 31 (54.8%) ‘management’ discussions with patients were not discussed with instructors during nCPs. Instructional ‘scaffolding’ (Bruner and Sherwood in Play: its role in development and evolution, p. 280, 1976) appeared limited regarding talk with and about patients. The limited and recontextualized reporting of patient concerns and experiences in nCPs represented lost opportunities to provide and learn patient-centered care. While Goffman’s (The presentation of the self in everyday life, p. 114, 1969) ‘front stage’ performances and Mishler’s (The discourse of medicine: dialectics of medical interviews, p. 14, 1984) healthcare ‘voices’ suggest separate worlds of talk before patients and instructors, we found these worlds were not wholly separate for neophyte speakers. Mediating concepts that influence clinical novices shifting their performances before their audiences, included: (1) pedagogical inconsistencies, (2) incompatible values associated with talk, (3) discordance between patient care and student education, (4) time limitations for teaching, and (5) insufficient instructional ‘scaffolding’ about talk.     

Time trends in exposure to environmental tobacco smoke and parental educational level for 6-year-old children in Germany

The aim of the study was to investigate the association between exposure to environmental tobacco smoke of 6-year-old children and parental educational level in Germany under the changing socioeconomic conditions after reunification. Logistic regression was used to examine the relationship between tobacco smoke exposure of children (current environmental tobacco smoke, maternal smoking during pregnancy, environmental tobacco smoke during the first 3 years of the child’s life) and the determinants parental educational level, time and region. In Germany, the risk of environmental tobacco smoke exposure among 6-year-old children was strongly associated with parental educational level (odds ratio: ≥2 ‘low’/‘middle’ versus ‘high’ parental educational level). In West Germany, environmental tobacco smoke exposure generally exhibited a decreasing trend of about 20%. In contrast, in East Germany the environmental tobacco smoke exposure was only decreasing for children of parents with higher education. The gap between low and high parental educational level with respect to current children’s tobacco smoke exposure has increased from 1991 to 2000 in East Germany. A considerable fresh increase of maternal smoking during pregnancy could be observed around 1991 in both parts of Germany. In East Germany, the transition from a socialist economic system to a market economy after reunification might in part explain the increased gap of tobacco smoke exposure between children of parents with lower and higher educational levels.     

Raised concentration of serum bile acids following occupational exposure to halogenated solvents, 1,1,2-trichloro-1,2,2-trifluoroethane and trichloroethylene

Objectives: The objectives of this study were␣threefold. First, to examine the hepatic effects of occupational exposure to 1,1,2-trichloro-1,2,2-trifluoroethane (FC 113) using conventional and newer tests (serum bile acids) of hepatobiliary function. Second, to assess the effects of altered work practices that included a reduced exposure to a different halogenated solvent (trichloroethylene) on the same parameters of liver function; and finally, to gather further data to support or refute the contention that serum bile acid (SBA) levels could provide a sensitive biological marker of exposure to these solvents. Design: Two groups of workers (control and exposed) in an Australian steel industry participated in the study. The exposed group (n = 5–6) comprised individuals who had either exposure to FC␣113 (68.2 ± 12.6 ppm) or trichloroethylene (8.9 ± 3.1 ppm) during the application of these solvents in a cleaning procedure, whereas the control group (n = 7–11) was composed of non-solvent-exposed office workers in the same company. The initial investigation involved exposure to FC 113 while a follow-up study was undertaken after changes in work practices were made including replacement of FC 113 with trichloroethylene (TRI). Methods: Standard liver function tests and individual serum bile acids (ISBA) were measured before and after exposure to solvents and simultaneously in the control subjects by enzymatic methods and high performance liquid chromatography (HPLC), respectively. Results: Statistical analysis of the data showed a significant increase in the concentration of total serum bile acids (TSBA), some of the subgroups of SBA, and a few of the ISBA in workers after a period of exposure to FC 113. After TRI replaced FC 113 together with other changes in work practices to give substantial reduction in exposure to solvent, a repeat study also found elevated SBA after the cleaning procedure but to a lesser extent. No other indications of adverse liver effects, as measured by conventional parameters of hepatobiliary function, were detected. Conclusion: Exposure to FC 113 was clearly associated with a significant rise in SBA levels, which are sensitive indicators of liver function. This finding is consistent with, and provides further support for, our previous investigations on chlorinated aliphatic hydrocarbon solvents which showed that SBA levels are a sensitive biological marker of exposure to these solvents. Changes in work practices including replacement of FC 113 resulted in a reduced effect on SBA, consistent with lower exposures. Received: 22 October 1996 / Accepted: 21 February 1997     

Dietary factors in relation to daily activity energy expenditure and mortality among older adults

Objectives  To examine the association between dietary factors to daily activity energy expenditure (DAEE) and mortality among older adults. Design and setting  A sub-study of Health, Aging, and Body Composition study. Participants  298 older participants (aged 70–82 years) in the Health, Aging, and Body Composition Energy Expenditure sub-study. Measurements  Dietary factors, DAEE, and all-cause mortality were measured in 298 older participants. Dietary factors include dietary intake assessed by the Block Food Frequency Questionnaire (FFQ), Healthy Eating Index (HEI), and self-reported appetite and enjoyment of eating. DAEE was assessed using doubly labeled water. All-cause mortality was evaluated over a 9 year period. Results  Participants in the highest tertile of DAEE were more likely to be men and to report having a ‘good’ appetite; BMI among men, proportion married, IL-6 and CRP levels and energy intake were also higher. Fewer black participants were in the ‘good’ HEI category. Participants in the ‘good’ HEI category had higher cognitive scores and a higher education level. Participants who reported improvement in their appetite as well as participants who reported a ‘good’ appetite were at lower risk for mortality (HR (95% CI): 0.42 (0.24–0.74) and 0.50 (0.26–0.88), respectively) even after adjusting for DAEE, demographic, nutritional and health indices. Conclusions  We showed an association between DAEE and appetite and mortality among well-functioning, community-dwelling older adults. These findings may have some practical use for the health providers. Inclusion of a question regarding appetite of an elderly patient may provide important information regarding risk for health deterioration and mortality.