Biomedical subjects

S Wing

Publications and source records attributed to S Wing.

60 records · Page 4Linked to original sources

PubMedDate not supplied

Missing annual external radiation dosimetry data among Hanford workers.

Epidemiological studies of workers employed at the Hanford Site have been underway for nearly 30 years. Although the external radiation dosimetry program at Hanford has been fairly comprehensive, some workers included in previous epidemiological analyses have periods of employment during which there are missing annual external radiation dosimetry records. In this report, employment history records and annual external dosimetry records have been used to investigate the extent of missing annual external dosimetry records for workers at the Hanford facility. A "nearby" procedure for estimating values for missing annual external dosimetry records was evaluated. Among the 33,459 workers who were employed at least 180 days and had at least one annual external dosimetry record, annual external dosimetry records were missing for 8% of the years of employment (32,323 missing annual external dosimetry records). Missing annual external dosimetry records were more common for female Hanford workers than for male workers, and for workers employed in the early years of Hanford's operation than for workers employed in later years of operation. The nearby procedure provided reliable estimates of values for missing annual external dosimetry records. Using this procedure, 18,937.5 mSv were estimated for missing annual external dosimetry records; this was 2% of the total recorded cumulative external radiation dose for these workers. Missing annual external dosimetry records should be considered as a potential source of bias and uncertainty in investigations of radiation-cancer associations among Hanford workers.

Air Pollution, Radioactive↗

PubMedDate not supplied

Evaluation of annual external radiation doses at values near minimum detection levels of dosimeters at the Hanford nuclear facility.

In epidemiological studies of workers exposed to ionizing radiation, recognition of the limitations of available radiation dosimetry data is important to interpretation of a study's findings. This paper provides an investigation of external radiation dosimetry data for workers at the Hanford nuclear facility, focusing on changes over time in practices for recording dosimetry measurements that were between zero and the minimum detectable level of a radiation dosimeter. Reported annual external radiation doses for the years 1944-1989 were examined for 33,459 workers; these records are the sum of periodic dosimetry measurements within a calendar year. For each year, the proportion of annual external doses with values in the range of minimum detectable level was examined. Contrary to previous researchers, we conclude that there is evidence that dosimetry measurements with values between zero and the minimum detectable level may have been recorded as zero in some historical periods. This conclusion is supported by evidence drawn from historical documentation about radiation dosimetry practices at the Hanford facility. Although workers at the Hanford facility have relatively complete and detailed external radiation dosimetry data compared to some other nuclear facilities that began operation in the 1940s, these data may suffer limitations related to dosimetry recording practices at the facility.

Adult↗

PubMedDate not supplied

Bahia-Carolina Program in Environmental and Occupational Health: A North-South partnership for workplace and environmental justice.

The Bahia-Carolina Program in Environmental and Occupational Health is an interdisciplinary collaborative program in research and training linking the Institute for Collective Health (ISC), the Federal University of Bahia, Brazil, and the School of Public Health, University of North Carolina at Chapel Hill. An important goal of this Fogarty Center-funded project is to improve workplace and environmental conditions and the well-being of the general population, particularly those workers in the informal sector. Major accomplishments include training taking place in the United States, training in Brazil, and support of Brazilian institutions. Brazilians studying in the United States have researched occupational risk factors for non-Hodgkin's lymphoma, the effectiveness of an environmental sanitation program, the health of refinery workers, and statistical methods for multilevel analysis, among other topics. The program also emphasizes the opportunity for U.S. faculty and students to learn from Brazilian colleagues. Challenges encountered in the collaboration process are described.

Brazil↗

PubMedDate not supplied

Cancer risk from low-level ionizing radiation: the role of age at exposure.

This article examines methodological issues related to epidemiologic investigations of the influence of age at exposure on radiation risk estimates; the epidemiologic literature on the role of age at exposure in radiation-cancer associations; and biological mechanisms that may account for associations observed in these studies. There is substantial evidence that young children, and especially the fetus, are highly vulnerable to ionizing radiation. Investigations also suggest that sensitivity may increase at the oldest ages of exposure. Further attention to modifying factors in radiation-cancer associations, such as age at exposure, may help to protect workers and the public by improving our understanding of sensitivity variation within populations.

Age Factors↗

PubMedDate not supplied

Recording of external radiation exposures at Oak Ridge National Laboratory: implications for epidemiological studies.

Accurate measurements of radiation exposure for individuals are critical to assessing radiation-mortality associations. This paper is based on a study of changes in recorded doses and in radiation monitoring programs at Oak Ridge National Laboratory, a U.S. Department of Energy facility where whole body external penetrating radiation exposures have been of primary epidemiological interest. External radiation monitoring data from 1943-1984 are analyzed for a group of white males (N = 8,318). The proportion of workers monitored for external radiation increased from about 50% in 1943 to over 80% in 1944 to above 98% after 1948. Mean radiation doses showed maxima in 1944 and 1957, followed by steady and long-term declines. Numerous changes in monitoring programs occurred during the study period, including changes in the types of dosimeters used, the frequency of reading dosimeters, methods of calculating doses, and practices of recording doses. Temporal patterns of doses in the lower range of the distribution showed some changes suggestive of changes in policies and practices for recording doses, which would influence dose values used in epidemiological studies. Reliable and accurate exposure measurements are especially important in studies of low level exposures due to small differences in outcomes between exposure groups. Evidence of changes in recorded doses due to monitoring and recording practices, rather than to actual changes in exposures in this well-monitored population, suggests the importance of comparable studies of other populations used for epidemiological studies of radiation-mortality associations.

Bias↗

PubMedDate not supplied

New long stay patients: from acute wards to where?

Inadequate alternatives to the old mental hospitals have placed many inner city acute psychiatric units under great pressure as bed numbers have contracted and disturbed patients have accumulated. This study set out to assess the outcome at two-year follow-up of a cohort of 26 patients resident on an acute psychiatric ward for more than six months. Results showed that a substantial minority of 'new long stay' patients made a successful return to independent living, but that at two-year follow-up half the cohort remained in a highly supported setting. Two deaths had occurred, neither by suicide. Psychiatric services remained involved with 90% of the patients in the cohort.

Adolescent↗