Documents Lie, Jenny-Anne S. 3 results

"Objective People living in industrialized societies have developed specific working schedules during the day and at night, including permanent night shifts and rotating night shifts. The aim of this study was to examine the association between circadian polymorphisms and rotating night shift work.Methods This cross-sectional study comprised 709 nurses and midwives (348 current rotating and 361 current day workers). Genetic polymorphism of selected clock genes BMAL1 (rs2279287), CLOCK (rs1801260), PER1 (rs2735611), PER2 (rs2304672), PER3 (rs10462020), CRY1 (rs8192440), CRY2 (rs10838527, rs10838527) was determined using real-time polymerase chain reaction (PCR) assays.Results There were no differences in BMAL1, CLOCK, CRY2, PER1, PER2, and PER3 genotypes among nurses and midwives working rotating night and day shifts. The frequency of women with rare CRY1 TT genotype was higher in the group of rotating night shift than day workers (17.0% versus 13.9%, P=0.06). Moreover, CRY1 TT genotype was associated with the total rotating shift-work duration, compared to women rarely working night shifts. Conclusions These results suggest that CRY1 (rs8192440) polymorphism may influence the adaptation to the rotating night shift work among nurses and midwives."

"Objective In order to devise effective preventive strategies, it is important to study workplace stressors that might increase the risk of workplace accidents - both affecting workers themselves as well as causing harm to third-parties. The aim of this report is to provide a systematic, updated overview and scientific review of empirical research regarding accidents in relation to long work hours and shift work, primarily based on epidemiological studies. Methods The search for articles was part of a large review study on the effects of work hours on various health outcomes, safety, and performance. The search strategy included 5 international scientific databases, and nearly 7000 articles were initially identified using our search string. Following the application of inclusion and exclusion criteria, 443 publications were found and evaluated using a pre-defined scoring system. Of these, 43 concerned safety and accidents but only 14 were considered to be of high quality (total score 2 or 3 on a scale from 0-3) and therefore used for this study.Results Both shift work and long working hours present a substantial and well-documented detrimental effect on safety - all the studies that are included in this review have one or more significant findings in this respect. The trends are quite coherent although the increases in accident rates are mostly from 50% to 100%. In epidemiological terms, this may be seen as rather small differences. The use of such data is therefore only of importance if the accident incidence is high or if accidents may have large effects.Conclusions The findings are most relevant to safety-critical activities such as the transport and health sectors. Work periods >8 hours carry an increased risk of accidents that cumulates, so that the increased risk of accidents at around 12 hours is twice the risk at 8 hours. Shift work including nights carries a substantial increased risk of accidents, whereas “pure” night work may bring some protection against this effect due to resynchronization. The evaluated studies give no clear indications of any age or gender being specifically susceptible or protected against the effects of work times scheduling on accident risk."

"A significant proportion of the work force is employed in unusual work schedules. The combined effects of working hours and chemical agents at the workplace may depend on the duration and/or timing of exposure. However, occupational exposure limits (OELs) usually assume working day-time, an 8-hour workday, 5 days/week and a 40-hour work week. The aims of this document were to review the scientific support for a combined effect of unusual working hours (shift work or extended working hours) and chemical exposure and, to the extent possible provide recommendations for down-adjustment of the OEL to account for unusual working hours. Animal data from chronopharmacological studies suggest that the time of exposure (day-night) may affect the biotransformation and toxicity of chemicals. A few epidemiological studies, i.e. regarding effects of dust and endotoxin on lung function, effects of acetone on sleep quality and tiredness, effects of carbon disulphide on coronary artery disease and effects of chemicals on spontaneous abortion, suggest more pronounced effects during night shifts compared to day shift exposure. However, the reviewed data are considered insufficient to conclude on recommendations for OEL adjustment for shift work. The Quebec method is recommended to adjust for extended working hours. Each chemical is assigned in categories based on the toxic effect. No adjustment is applied for ceiling values, short-term exposure limits and limit values based on asphyxiation, irritation or malodour. For other substances producing effects following short- or long-term exposure, the method is based on Haber's rule and the type of adverse effect."