Comparative assessing for radiological, chemical, and physical exposures at the French uranium conversion plant: Is uranium the only stressor?

Our plain-English summary of Comparative assessing for radiological, chemical, and physical exposures at the French uranium conversion plant: Is uranium the only stressor?, by I. Guseva Canu, F. Paquet, M. Goldberg, et al (International Journal of Hygiene and Environmental Health, 2009).

The study

• Authors: I. Guseva Canu, F. Paquet, M. Goldberg, B. Auriol, P. Bérard, P. Collomb, J.C. David, G. Molina, P. Perez, M. Tirmarche
• Journal: International Journal of Hygiene and Environmental Health
• Published: 2009;212(4):398-413
• Cited by: 18 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

This study presents the pattern of exposure to uranium and other occupational pollutants known to be potentially carcinogenic, mutagenic or toxic and used at the main uranium conversion plant in France. For different uranium compounds specified according to their solubility and purity, and 16 other categories of pollutants: chemicals, fibres, vapours, dust, and heat a time- and plant-specific job exposure matrix (JEM) was created covering the period 1960-2006. For 73 jobs and for each pollutant the amount and frequency of exposure were assessed on a four-level scale by different time periods. The JEM shows 73% sensitivity and 83% specificity. Although exposure assessment was semi-quantitative, the JEM allows computing of individual cumulative exposure score for each pollutant across time. Despite the predominant natural uranium compounds exposure, the amount of exposure to other pollutants such as TCE and other chlorinated products, asbestos, and fibres, is important at the plant. Numerous correlations detected between uranium compounds exposure and exposure to chemicals warrants improving biological monitoring of exposed workers and accounting for associated exposures in epidemiological studies. Results of this study will be used for further investigation of association between exposure and mortality among uranium conversion workers cohort.

In plain English

The authors built a job exposure matrix, a tool assigning estimated exposure levels to jobs and time periods, for the AREVA NC uranium conversion plant in Pierrelatte, France, covering 1960 to 2006. The study did not look at disease. Experts defined 73 jobs (232 job-period pairs) and 22 exposure agents, including uranium compounds, trichloroethylene (TCE), asbestos and other fibres. Then 353 active and retired workers, each rating only jobs they knew personally, scored how often exposure occurred and the quantity of product handled. Applied to 2709 workers, the matrix classed 1894 (69.97%) as exposed to asbestos and 2253 (83.23%) to fast-absorbed natural uranium compounds. Compared with medical records, overall kappa was 0.56, sensitivity 0.72 and specificity 0.83. For asbestos, agreement was poor (kappa 0.09); the authors said this was probably because medical files recorded such products less systematically. Asbestos exposure correlated with exposure to TCE and other chlorinated products. The authors concluded that, despite predominant natural uranium exposure, exposure to pollutants such as TCE and asbestos was important at the plant. They named the lack of usable measurement data as a major obstacle.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Retrospective exposure assessment: construction and validation of a plant-specific job exposure matrix (no health outcomes studied)
• Who was studied: AREVA NC uranium conversion plant, Pierrelatte, south-east France, 1960–2006. There were 73 jobs divided into 232 job-period pairs. Exposure was scored by 353 workers: 182 active workers out of 182 contacted and 171 retired workers out of 550 contacted. Each respondent assessed only job-period pairs they were personally familiar with. The matrix was applied to 2709 plant workers.
• Exposure: 22 exposure agents. These included natural and reprocessed uranium compounds grouped by absorption type (fast, moderate, slow), chlorinated agents, TCE, fluoride and nitrogenous agents, and aromatic solvents. Also covered were asbestos (fireproofing, insulation and braids), vitreous fibres and rock wool, refractive ceramic fibres, chromate, lead, mercury, silica, hydrazine and other fuels, welding fumes, and heat. Each job-period pair was scored on four-level scales for frequency of exposure and for the quantity of product the worker handled.
• Main results:
  • Of the 2709 workers, 1894 (69.97%) were classed as exposed to asbestos.
  • Of the 2709 workers, 2253 (83.23%) were classed as exposed to fast-absorbed natural uranium compounds.
  • Compared with medical records from a random 1% sample of workers, the matrix showed poor agreement for asbestos (kappa 0.09; observed agreement 0.61, sensitivity 1.00, specificity 0.60).
  • Across all exposure categories compared with medical records, observed agreement was 0.78, kappa 0.56, sensitivity 0.72 and specificity 0.83.
  • Asbestos, glass wool and rock wool were found in around 50% of jobs. Asbestos exposure correlated with exposure to TCE and other chlorinated products; the article does not show these data.
• The authors' conclusion: The authors concluded that, despite the predominant exposure to natural uranium compounds, exposure to other pollutants known as carcinogenic, mutagenic or toxic, such as TCE and asbestos, was important at the plant. They said correlations between uranium and chemical exposures call for better monitoring, and for associated exposures to be accounted for in epidemiological studies.
• Limitations the authors state:
  • There were no usable instrument measurement data, so the exposure assessment was semi-quantitative.
  • The matrix does not account for accidental exposures.
  • Medical records, used as the validation reference, recorded asbestos and some chemicals less systematically. The plant's first asbestos inventory dates only from 1997.

Topics

Medical terms in this study, explained in our Lexicon: Carcinogenic, Cumulative Exposure.

Related studies

• Impact of chemical exposure on cancer mortality in a French cohort of uranium processing workers — S. Zhivin, D. Laurier, et al. (2013)
• French cohort of the uranium processing workers: mortality pattern after 30-year follow-up — I. Guseva Canu, E. Cardis, et al. (2010)
• Study of the count-to-mass conversion factor for asbestos fibres in samples collected at the emissions of three industrial plants — S. Puledda, A. Marconi (1991)
• Errors and blunders in the estimation of radiation exposure for the uranium miners of WISMUT in Germany — G.G. Eigenwillig (2006)
• An experiment to develop conversion factors to standardise measurements of airborne asbestos — M. Dodic-Fikfak (2007)
• Analyses of radiation and mesothelioma in the US Transuranium and Uranium Registries — H. Gibb, K. Fulcher, et al. (2013)

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