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Purpose: Epidemiological studies in nuclear industry workers can produce relevant information to better appreciate the health risks related to chronic external exposure to low doses of ionizing radiation (IR). This work examined the relations between exposure to IR and mortality in workers at the French Electricity Company (EDF), followed up to year 2003., Methods: Permanent staff who had worked for at least 1 year at EDF during period 1961-1994 and who had been monitored for exposure to IR were included (n = 22,393). One-sided trend tests for mortality according to cumulative dose and relative risks at 100 mSv were estimated using Poisson regression. Main analyses were stratified on age, sex, calendar time and education., Results: A total of 874 deaths occurred, and 66 workers were lost to follow-up. Median age at end of follow-up was 48. None of the causes of death investigated increased significantly according to dose, except cerebrovascular diseases (p = 0.01), but this last observation was based on only 22 cases., Conclusions: These results do not allow dismissing a possible influence of IR on cancer risk in this population. The cohort is still relatively young and therefore confidence intervals for estimated relative risks remain wide, although they have considerably narrowed since a previous analysis. Chance is a possible explanation for the association between IR and cerebrovascular mortality, due to the low number of cases on which it is based. These results thus need to be stabilized by conducting joint analyses with similar cohorts.

Control of the risk of internal exposure of EDF PWR plant maintenance workers by alpha-emitting radioactive elements is based on identification and quantification of the contamination of the systems. In 2001, an experiment carried out at Cattenom Power Plant during a unit outage in the presence of a leaking fuel cladding, based on measurement of alpha-emitting radioactive elements, made it possible to determine a realistic particle resuspension coefficient. A resuspension coefficient of 10(-6) m(-1) was adopted for operational radiological protection. An appropriate monitoring system for workers was set in place in collaboration with the occupational medicine and radiological protection department. It was based on prior estimation of the level of alpha contamination, and confirmed by swipe measurements, atmospheric surveillance by monitors, and collective analysis by nose blow samples from workers selected on the basis of their workstations, as well as supplementary individual measurements (monitoring of faeces). This surveillance made it possible to validate an appropriate work area monitoring system.

With a view to providing help for occupational doctors supervising nuclear plant workers, this article explains what "recommendations" means for the law make. It is the advice and counselling provided to doctors in order to heighten their awareness of specific problems; it does not mean instructions or stipulations to be scrupulously executed. A team of EDF (National French Electricity Board) doctors proposes an interpretation of these recommendations showing that they can help doctors evaluate the ability of workers according to their age, their antecedents, and the job's requirements. Thus, doctors are given greater freedom in the selection, frequency and interpretation of complementary examinations. Finally, the article develops the administrative aspect (filing, dosimetry) of worker supervision, and its connection with medical supervision.

An epidemiological study of ragweed allergy was conducted on 646 employees belonging to 6 factories located in the Rhone valley south of the city of Lyon. Information on seasonal evocative clinical symptoms was obtained through a self-administered questionnaire. Biological prevalence was assessed by measuring anti-ragweed IgE specific antibodies. Measurements were performed by immunoenzymatic assay (W1 Phadezym RAST from Pharmacia). 34 (5,4%) subjects had evocative symptoms whereas 37 (5,9%) had increased specific IgE. Persons with the highest IgE levels were symptomatic. Concordance between symptoms and biology was 35% (12/34). Results indicate that sensitization level varies according to the location of the factory and people's residence, the risk to become allergic being of 10% in the most exposed population. This data emphasize the need to promote anti-ragweed eradication policy.