Biological and chemical monitoring of occupational exposure to ethylene oxide

Studies were carried out on two populations occupationally exposed to ethylene oxide (EtO) using different physical and biological parameters. Blood samples were collected from 9 hospital workers (EI) and 15 factory workers (EII) engaged in sterilization of medical equipment with EtO and from matched controls (CI and CII). Average exposure levels during 4 months (the lifespan of erythrocytes) prior to blood sampling were estimated from levels of N-(2-hydroxyethyl)valine adducts in hemoglobin. They were significantly enhanced in EI and EII and corresponded to a 40-h time-weighted average of 0.025 ppm in EI and 5 ppm in EII. Exposures were usually received in bursts with EtO concentrations in air ranging from 22 to 72 ppm in EI and 14 to 400 ppm in EII. All samples were analyzed for HPRT mutants (MFs), chromosomal aberrations (CAs), micronuclei (MN) and SCEs. MFs were significantly enhanced by 60% in EII but not in EI. These results are the first demonstration of mutation induction in man by ethylene oxide. CAs were significantly enhanced in EI and EII by 130% and 260% respectively. MN were not enhanced in EI but significantly in EII(217%). The mean frequency of SCEs was significantly elevated by 20% in EI and by almost 100% in EII. SCE was the only parameter that allowed distinction between daily and occasionally exposed workers in EII. An interesting finding in exposed workers was the large increase of the percentage of cells with high frequencies of SCE (3–4 times in EI and 17-fold in EII).

The relative sensitivity of endpoints for detection of EtO exposure in the present investigation was in the following order: HOEtVal adducts > SCEs > chromosomal aberrations > micronuclei > HPRT mutants.     

护士职业压力与职业倦怠的相关性研究

目的:了解护士职业压力、职业倦怠现状;探讨两者之间的关系。方法:方便抽样,抽取哈尔滨市5所三级医院的468名护士进行问卷调查。采用护士一般情况调查表、护士工作压力源量表、职业倦怠量表进行调查。结果:护士职业倦怠程度为中等,去人格化属于中度倦怠,情感衰竭、低成就感程度达到了高度倦怠;职业压力得分为87.56±20.43,以工作量及时间分配维度压力最高,病人护理维度压力最低。情感耗竭与除工作环境及资源之外的职业压力维度呈显著正相关;去人格化与职业压力各维度均呈显著正相关;低成就感与职业压力中护理专业及工作、病人护理呈显著负相关(P0.05)。护士职业压力各维度对其职业倦怠的3个维度均有较好的预测作用,尤其对护士情感耗竭的解释程度达25.5%。结论:护士职业倦怠现象不容忽视,护理管理者有针对性的对护士进行管理,鼓励护士加强自身修养、学会自我疏导,适当授权等是降低护士职业倦怠的正性激励措施。     

Vital working hour schemes: The dynamic balance between various interests

“Balancing Interests”, the theme of the 17th International Symposium on Shift Work and Working Time held in Hoofddorp, The Netherlands (September 2005), refers to the ambition to reach an optimal balance between the various aspects of shift work. Economic, ergonomic, physical, and psychosocial factors all interact in determining the impact of shift work at the individual, organizational, and societal level. It is the challenge of this multidisciplinary field of research to model all relevant factors in such a way that it will allow us to optimize the dynamic trade-off between the yield and the risk of shift work. The organizers of the 17th International Symposium and the co-editors of these proceedings are convinced that the high quality of the contributions will bring us closer to this ultimate goal.     

Determination of six hydroxyalkyl mercapturic acids in human urine using hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC–ESI-MS/MS)

Mercapturic acids are increasingly used as biomarkers for exposure to certain carcinogenic substances. Glycidol, ethylene oxide, propylene oxide, acrolein and 1,3-butadiene are important intermediates of toxicological concern used in the industrial production of various chemicals. The main urinary metabolites of these alkylating substances are hydroxyalkyl mercapturic acids. Therefore, we developed and validated an analytical method for the simultaneous determination of six hydroxyalkyl mercapturic acids in human urine after solid phase extraction. The mercapturic acids were separated using hydrophilic interaction liquid chromatography (HILIC) and quantified by tandem mass spectrometry using isotopically labelled internal standards. The developed method enables for the first time the determination of 2,3-dihydroxypropyl mercapturic acid (DHPMA), a metabolite of glycidol, in human urine. Additionally, the mercapturic acids of ethylene oxide (hydroxyethyl mercapturic acid, HEMA), propylene oxide (2-hydroxypropyl mercapturic acid, 2-HPMA), acrolein (3-hydroxypropyl mercapturic acid, 3-HPMA) as well as of 1,3-butadiene(3,4-dihydroxybutyl mercapturic acid, DHBMA and monohydroxy-3-butenyl mercapturic acid, MHBMA) can be determined. The limits of detection range from 3.0 to 7.0 μg/L. Intra- and inter-day precision was determined to range from 1% to 9%. Due to the good accuracy and precision and the low limits of detection the developed method is well suited for the determination of occupational exposure to alkylating substances as well as for the determination of background concentrations of the respective mercapturic acids in the general population.     

Occupational exposure in a PET/CT facility using two different automatic infusion systems

PurposeThe aim of this study was to measure the occupational exposure using active personal dosimeters (APD) in the PET/CT department at different stages of the operation chain i.e. radiopharmaceutical arrival, activity preparation, dispensing, injection, patient positioning, discharge and compare the radiation exposure doses received using two automatic injection/infusion systems. This paper also reflects optimization processes that were performed to reduce occupational exposure.MethodsMeasured APD data were analysed for medical physicists, radiology technologists and administrative staff from 2014 till 2018. For dispensing and injecting ¹⁸F-FDG, the automatic infusion/injection system IRIDE (Comecer, Italy) or the automatic fractionator ALTHEA (Comecer, Italy) with wireless injection system WIS (Comecer, Italy) were used. Radiation exposure optimization methods were applied during the data collection period (installation of the transport port, patient management, APD alarm threshold and etc.).ResultsRadiology technologists who perform injection procedures, regardless of the automatic infusion system, received the highest radiation exposure dose. The average doses to the radiology technologists per one study were 1.72 ± 0.33 μSv and 1.16 ± 0.11 μSv with ALTHEA/WIS and IRIDE system, respectively. The average dose for accompanying the patient to the PET/CT scanner and scan procedure was 0.52 ± 0.07 μSv. For the medical physicists, the average dose was 0.29 ± 0.09 µSv. The measured dose for administrative staff was 0.30 ± 0.15 μSv.ConclusionsOccupational exposure can be effectively optimized by different means including staff monitoring with APD, implementation of radiation safety culture and the usage of automatic infusion systems.     

不同职业人群对口罩的选择与正确佩戴

口罩是预防呼吸道暴露的重要防线,正确选择和佩戴口罩可以降低新型冠状病毒(2019 novel coronavirus,2019-nCoV)等呼吸道传播病原感染的风险。但是,口罩类型、防护等级、职业性质、工作环境和防护要求以及正确的佩戴方式均会影响防护效果。本文以国家标准、行业标准以及诊疗方案等资料为参照,针对不同职业人群对口罩的选择与佩戴的关键点展开论述,为不同人群正确使用口罩提供参考,降低各类人群的暴露风险,以利于疫情的控制。     

Urethrographic examinations: Patient and staff exposures and associated radiobiological risks

Medical exposure of the general population due to radiological investigations is the foremost source of all artificial ionising radiation. Here, we focus on a particular diagnostic radiological procedure, as only limited data are published with regard to radiation measurements during urethrograpic imaging. Specifically, this work seeks to estimate patient and occupational effective doses during urethrographic procedures at three radiology hospitals. Both staff and patient X-ray exposure levels were calculated in terms of entrance surface air kerma (ESAK), obtained by means of lithium fluoride thermoluminescent dosimeters (TLD-100(LiF:Mg:Cu.P)) for 243 urethrographic examinations. Patient radiation effective doses per procedure were estimated using conversion factors obtained from the use of Public Health England computer software. In units of mGy, the median and range of ESAK per examination were found to be 10.8 (3.6–26.2), 7.0 (0.2–32.3), and 24.3 (9.0–32.0) in Hospitals A, B, and C, respectively. The overall mean and range of staff doses (in µGy) were found to be 310 (4.0–1750) per procedure. With the exception of hospital C, the present evaluations of radiation dose have been found to be similar to those of previously published research. The wide range of patient and staff doses illustrate the need for radiation dose optimisation.     

The Impact of Rest Breaks on Temporal Trends in Injury Risk

This study examined the impact of rest breaks on temporal trends in industrial accident risks in an attempt to replicate earlier findings of a linear increase in risk as a function of elapsed time on task. In two separate studies, the trend in work‐related injuries were studied in relation to the timing of rest breaks. In study one, comparisons were made between on‐ and off‐track workers on weekly rotating three‐shift systems operating in a large engineering company. Records of on‐duty injuries that occurred over 12 months were examined (N=4645 incidents). Study two involved interviewing patients who had suffered work‐related hand injuries in a variety of occupational settings (N=407 patients). Hierarchical log linear analysis was used in both studies. In study one, risk increased from the first to the second half‐hour of continuous work following a break, but then remained relatively constant in subsequent half‐hour periods, although there was a fall in the third half‐hour for on‐track workers. In some of the data, there was also a decrease in risk in the period leading up to the end of a work period. There was a sharp decline in reported injuries toward the very end of a shift, but otherwise the observed trends did not differ between successive periods of continuous work or between morning, afternoon, and night shifts. In study two, risk increased from the first to the second half‐hour of continuous work and then remained relatively constant in the third half‐hour. The contrast between the current and previous findings may be due to the relatively unique work environment of the previous study. It is suggested that the current trends reflect the effects of working in a relatively unconstrained task environment, and that causes other than fatigue may underlie the trends observed in both the previous and current studies.     

Urinary excretion of 1-hydroxypyrene as a biomarker of exposure to polycyclic aromatic hydrocarbons from different sources

1-Hydroxypyrene (1-OHP) urinary excretion has been studied in subjects exposed to polycyclic aromatic hydrocarbons (PAH) from different sources (urban air pollution, cigarette smoking, food contamination or occupational exposure). In Study A, statistically significant differences among subjects categorized according to daily cigarette consumption were observed: 1-OHP median excretion of heavy smokers (more than 20 cigarettes per day; 1-OHP=371 ng l^-1; n=6) was significantly increased over that of non-smokers (1-OHP=160 ng l^-1; n=79), light smokers (less than 10 cigarettes per day,1-OHP=157 ng l^-1; n=7) and also medium smokers (10-20 cigarettes per day, 1-OHP=154 ng l^-1; n=13) (p<0.04). In smokers, 1-OHP excretion (y, ng l^-1) increased with the intensity of cigarette consumption and was associated with self-reported number of cigarettes smoked daily (x, n) (y=20+16.6x; r=0.58, n=22, p<0.01), urinary thiocyanate (x, µmoll^-1) (y=55+2.6x; r=0.57, n=20, p<0.01) and cotinine (x, µg l^-1) (y=89+0.23x; r=0.62, n=17, p<0.01). In Study B the influence of smoked food consumption on 1-OHP excretion was evaluated: 1-OHP excretion began to increase as soon as 3 h after a PAH-rich meal and peak values were reached between 6 and 9 h after lunch. Maximum excretion mean values were respectively 525 ng l^-1 for non-smokers (n=8) and 650 ng l^-1 for smokers (n= 4). 1-OHP concentrations in next-morning samples were back to pre-lunch levels both for non-smokers and smokers. In Study C non-smoker workers (n=28) occupationally exposed to PAH in a steel plant were investigated. At values of airborne pyrene ranging between 6 and 30 µg m^-3, excretion values of 1-OHP up to 80000 ng l^-1 were observed. The use of urinary 1-OHP as a screening test to discriminate between smokers and non-smokers in the presence of uncorrected dietary influence has been calculated according to a cut-off value of 461 ng l^-1 (reference group upper limit): the 1-OHP positive predictive value is 57%, its predictive negative value is 77%, sensitivity is 15% and specificity is 96%. In conclusion, 1-OHP appears to be a valuable biomarker of pyrene exposure. It will be nevertheless more accurate in assessing human PAH exposure from multiple sources if the influence of different kinetics for inhaled (particulate or gaseous) or ingested PAH are considered and if the role of oxidative polymorphism is adequately elucidated. The possibility of using 1-OHP to estimate the total burden of PAH from different sources or of screening groups with different PAH exposure appears to be a possible approach. However, the use of 1-OHP to evaluate the associated risk of cancer is still a premature target.     

职业倦怠与抑郁症的相关性及其生物学基础研究*

职业倦怠和抑郁症是当今社会人群中普遍存在的影响心理健康的重要因素和疾病,这两者之间有一定的相关性.职业倦怠主要表现在三个方面:情感枯竭,去个性化,个人成就感缺乏.抑郁症主要表现在心境障碍或情感性障碍,缺乏激情.职业倦怠和抑郁症在表现行为方面存在一定关联,患有职业倦怠和抑郁症的人通常态度消极,缺乏对生活和工作的热情,自我评价低,影响工作和生活质量.抑郁情绪易引发职业倦怠,职业倦怠也可以导致抑郁症,二者相互影响.本文就职业倦怠与抑郁症的概念,两者之间的联系及相关的生物学基础进行了综述.