Reducing the particle size of materials is an efficient and reliable tool for improving the bioavailability of a gene or drug delivery system. In fact, nanotechnology helps in overcoming the limitations of size and can change the outlook of the world regarding science. However, a potential harmful effect of nanomaterial on workers manufacturing nanoparticles is expected in the workplace and the lack of information regarding body distribution of inhaled nanoparticles may pose serious problem. In this study, we addressed this question by studying the body distribution of inhaled nanoparticles in mice using approximately 50-nm fluorescent magnetic nanoparticles (FMNPs) as a model of nanoparticles through nose-only exposure chamber system developed by our group. Scanning mobility particle sizer (SMPS) analysis revealed that the mice were exposed to FMNPs with a total particle number of 4.89 × 10⁵ ± 2.37 × 10⁴/cm³ (low concentration) and 9.34 × 10⁵ ± 5.11 × 10⁴/cm³ (high concentration) for 4 wk (4 h/d, 5 d/wk). The body distribution of FMNPs was examined by magnetic resonance imaging (MRI) and Confocal Laser Scanning Microscope (CLSM) analysis. FMNPs were distributed in various organs, including the liver, testis, spleen, lung and brain. T2-weighted spin-echo MR images showed that FMNPs could penetrate the blood-brain-barrier (BBB). Application of nanotechnologies should not produce adverse effects on human health and the environment. To predict and prevent the potential toxicity of nanomaterials, therefore, extensive studies should be performed under different routes of exposure with different sizes and shapes of nanomaterials.

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To clarify genotoxic effects of occupational exposure to antineoplastic drugs in Japan, we examined DNA damage, assessed by the comet assay, in 121 female nurses and 46 female clerks working at three hospitals in the northeast of Japan. The comet assay is considered to be a sensitive and rapid method for DNA strand break detection in individual cells, and tail length and tail moment are used as the comet parameters. Concerning the basal characteristics, the 46 control subjects had higher rates of smoking and coffee-drinking habits and lower hemoglobin than the 121 nurses (p<0.05). The log-transformed tail length in the nurses was significantly longer than that in the control subjects after adjusting for possible covariates such as age and smoking habit (p<0.05). Also, the log-transformed tail length was significantly longer, in the 57 nurses who had handled antineoplastic drugs in the last six months, than that in the 46 control subjects (p<0.05); but, no significant difference in tail length or tail moment was seen between the two nurse groups with and without experience of handling hazardous drugs (p>0.05). These results suggest that Japanese nurses who have worked at hospitals using antineoplastic drugs may have a potential risk of DNA damage. To minimize this risk in Japan, use of biological safety cabinet and appropriate protective equipments, in addition to staff education and training, should be implemented in the healthcare environment.

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Due to the potential for an influenza pandemic, preparedness for infection control in healthcare settings is essential from the standpoint of occupational health for healthcare workers. We conducted questionnaire surveys among Japanese hospitals to assess preparedness at the individual and institutional levels and their inter-relationship. Questionnaires were administered at 7 tertiary hospitals in Japan during the spring of 2006. We analyzed 7,378 individual responses of the 10,746 questionnaires administered and all seven institutional responses by hospital infection control committees. Healthcare workers assigned low importance to personal protective equipment and showed mixed attitudes (anxious but accepting) to the potential risk. Institutional gaps existed in preparedness across hospitals and most hospitals lacked the specificity to cope with a pandemic. A higher level of institutional preparedness, as determined by expertise as well as general and specific countermeasures, was an important predictor of individual recognition of preventive measures, perception of institutional measures, and attitude toward coping with risk. A higher level of institutional preparedness stood out to be an important predictor of individual preparedness. Considering the risk of a future influenza pandemic, hospitals should improve preparedness at all levels.

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To date, the understanding of how recovery from work relates to cortisol output is poor. Considering this, the present study set out to investigate the associations between self-ratings of 15 items of rest and recovery and salivary cortisol sampled every second hour across two working days. Data came from 12 female and 13 male white-collar workers and were analyzed by linear regression analyses and repeated measures ANOVA. Poor rest and recovery was associated with high levels of morning cortisol, with the strongest relationships emerging for "rested in the morning", "rested after a weekend", "feel energetic during the working day", "tired during the working day", "sufficient sleep" and "worry about something". Moreover, significant interaction effects emerged between sex and "rested after a weekend" and "worry about something". To conclude, the findings show that self-ratings of rest and recovery are related to cortisol, particularly to morning cortisol, and that self-ratings provide important information on physiological recovery in terms of cortisol output.

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This study assessed the relationships of physical job demands (PJD), smoking, and alcohol abuse, with premature mortality before age 70 (PM-70) among the working or inactive population. The sample included 4,268 subjects aged 15 or more randomly selected in north-eastern France. They completed a mailed questionnaire (birth date, sex, weight, height, job, PJD, smoking habit, alcohol abuse (Deta questionnaire)) in 1996 and were followed for mortality until 2004 (9 yr). PJD score was defined by the cumulative number of the following high job demands at work: hammer, vibrating platform, pneumatic tools, other vibrating hand tools, screwdriver, handling objects, awkward posture, tasks at heights, machine tools, pace, working on a production line, standing about and walking. The data were analyzed using the Poisson regression model. Those with PM-70 were 126 (3.81 per 1,000 person-years). The leading causes of death were cancers (46.4% in men, 57.1% in women), cardiovascular diseases (20.2% and 11.9%), suicide (9.5% and 7.1%), respiratory diseases (6.0% and 4.8%), and digestive diseases (2.4% and 4.8%). PJD3, smoker, and alcohol abuse had adjusted risk ratios of 1.71 (95% CI 1.02-2.88), 1.76 (1.08-2.88), and 2.07 (1.31-3.26) respectively for all-cause mortality. Manual workers had a risk ratio of 1.84 (1.00-3.37) compared to the higher socio-economic classes. The men had a two-fold higher mortality rate than the women; this difference became non-significant when controlling for job, PJD, smoker and alcohol abuse. For cancer mortality the factors PJD3, smoker, and alcohol abuse had adjusted risk ratios of 2.00 (1.00-3.99), 2.34 (1.19-4.63), and 2.22 (1.17-4.20), respectively. Health promotion efforts should be directed at structural measures of task redesign and they should also concern lifestyle.

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Identification of the specific pollutants contributing most to the health hazard of the air pollution mixture may have important implications for environmental and social policies. In the current study, we conducted a time-series analysis to examine the specific effects of major air pollutants [particulate matter less than 10 microns in diameter (PM₁₀), sulfur dioxide (SO₂), and nitrogen dioxides (NO₂)] on daily mortality in Shanghai, China, using both single-pollutant and multiple-pollutant models. In the single-pollutant models, PM₁₀, SO₂, and NO₂ were found to be associated with mortality from both all non-accidental causes and from cardiopulmonary diseases. Unlike some prior studies in North America, we found a significant effect of gaseous pollutants (SO₂ and NO₂) on daily mortality even after adjustment for PM₁₀ in the multiple-pollutant models. Our findings, combined with previous Chinese studies showing a consistent, significant effect of gaseous pollutants on mortality, suggest that the role of outdoor exposure to SO₂ and NO₂ should be investigated further in China.

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The determination of the current antiblastic drug contamination levels in an Italian hospital oncology ward was carried out. Statistical evaluation of data aiming to identify potential exposure causes was performed. Cyclophosphamide (CP), ifosfamide (IF) and 5-fluorouracil (5-FU) were determined by wipe tests, extracted with diatomaceous earths and quantified by GC/MSMS or HPLC/UV. Data were analysed with respect to the potential contamination levels of sampled surfaces, and various amounts of handled analyte. χ² tests and Spearman correlation coefficients were calculated. Median concentration levels of 0.086, 0.071, 2.363 μg/dm² were obtained, (CP, IF, 5-FU, respectively). 3.8 and 13.5% of investigated surfaces showed CP and IF concentrations higher than 1 μg/dm² (up to 26.96 μg/dm²) and 13.4% of samples contained 5-FU concentrations in the range 20-208.9 μg/dm². Analytes' concentration levels were dependent on sampling sites, with significant correlations showing a progressive contamination decrement going from workbenches, floor, hood planes and other surfaces. A diffuse contamination (traces of all the three analytes) was found on all investigated surfaces, even when analytes had not been used during the sampling days. A significant correlation (ρs=0.303, p=0.001) between the measured analyte concentration and the analyte handled amount was found only in the case of IF. The risk management strategy should be improved, as suggested by the measured and widespread levels of contamination. Since contamination also depends on other factors attributable to working modalities and cleaning procedures, the obtained results suggest that performance of specific training courses as well as scheduling environmental monitoring plans to achieve an actual decrement of the observed contamination levels should be implemented.

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In this study, we evaluated the effects on subjective discomfort among cooks during food preparation through use of a standing aid that we developed to alleviate the workload on the low back in the forward-bent posture. Twelve female cooks who worked in a kitchen in a nursing home were asked to prepare foods in 2 working postures: (a) supported by the standing aid (Aid) and (b) without the aid (No aid). They were instructed to evaluate discomfort in 13-body regions during food preparation and the degree of fatigue at the day's end and to enter their ratings after the end of the workday. Since a significant correlation was observed between body height and the improvement effect of discomfort through use of the standing aid, cooks were divided into two groups according to the height, and ratings were analyzed in each group. Among the tall cooks, subjective discomfort in the low back and the front and back of thighs was significantly less with the Aid posture than with the No aid posture. However, in short cooks these values tended to increase in the Aid posture compared with the No aid posture. The results suggest that the standing aid was effective in alleviating tall cooks' workload on the low back in the forward-bent posture.

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The present study examined degrees of job-related stress factors as well as mental and physical symptoms among Japanese hospital nurses in various departments, and clarified associations of departments and job-related stress factors with those symptoms. A self-administered anonymous questionnaire was distributed to 1,882 full-time nurses at four acute care hospitals in Japan. The survey included demographic factors, and the Brief Job Stress Questionnaire. Among 1,599 nurses who completed all items relevant to the present study, we analyzed data from 1,551 female nurses. The results show that working in operating rooms was associated with fatigue, that working in intensive care units (ICU) was associated with anxiety, and that working in surgery and internal medicine was associated with anxiety and depression independently of demographic factors and job-related stress factors. The physical and mental health of nurses might affect their time off, quality of nursing care and patient satisfaction in acute care hospitals. Therefore, job-related stress factors should be minimized, to improve the physical and mental health of nurses, considering unique departmental demands.

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We conducted a questionnaire survey in order to grasp the actual conditions under which antineoplastic drugs are mixed for injection in hospitals. Questionnaires were sent to all 155 hospitals with 100 or more beds for general patients in Osaka Prefecture, Japan. The response rate was 69.0%. Mixing of antineoplastic drugs was done in 81.3% of the hospitals. The questionnaire was answered by doctors in 17.2% of the hospitals with antineoplastic drugs, nurses in 11.5%, and pharmacists in 70.1%. Mixing of antineoplastic drugs was done by doctors in 58.6% of the hospitals, nurses in 44.8%, and pharmacists in 63.2% (multiple answers). Occupational exposure to antineoplastic drugs was recognized in 97.7% of the hospitals. The mean frequency of the mixing operation was 8.8 d per month per worker. The mean number of antineoplastic drugs handled was 7.4 types. Guidelines for the safe handling of antineoplastic drugs were used in 52.8% of the hospitals and a biological safety cabinet was available in 57.4%. Gloves, mask, gown and goggles were used in 82.7, 69.0, 62.1 and 36.8% of the hospitals, respectively, but no personal protective equipment was used in 10.1%. The safety precautions of the hospitals in which the number of beds was small tended to be fewer than those of the hospitals in which the number of beds was large. Used vials and ampoules were disposed of as clinical, infectious or exclusive antineoplastic drug waste by 74.7% of the hospitals. Safety measures for handling the excrement of patients treated with antineoplastic drugs were performed in 8.0% of the hospitals. In 43.7% of the hospitals, the responders had experienced accidents during antineoplastic drug preparation, such as drugs adhering to hands or eyes, drug leakage, accidental injection and cutting by ampoules. Because of the adverse effects of antineoplastic drugs, all hospitals in which the healthcare workers handle them should promote safety precautions.

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A harsh psychosocial environment in the workplace might cause adverse health events, but the association has not been well demonstrated in the penitentiary environment. This cross-sectional study was designed to explore the association between workplace psychosocial risks and the mental health of correctional officers in a Spanish penitentiary center. A self-administered questionnaire was distributed to correctional officers. A total of 164 responded anonymously (response rate 43%). The SF36 survey was used to measure mental health and ISTAS21 (Spanish version of Copenhagen Psychosocial Questionnaire) was used to measure exposure to workplace psychosocial conditions. Low scores were obtained for mental health, high scores were obtained for psychological demands, low self-esteem, and low control and influence and moderate scores for low social support, double exposure, and insecurity at work. A linear regression analysis was constructed to study the influence of workplace psychosocial conditions (independent variables) on mental health (dependent variable). The effect was adjusted for sex, age, seniority, and occupational group. Psychological demands (highest impact), low control and influence, and double exposure had significant inverse associations with mental health. The association between low social support, low self-esteem, and insecurity at work with mental health was insignificant. Psychosocial work conditions are a potential target for mental health promotion programs at work.

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