Occupational Exposure to Trichloroethylene and Cancer Risk for Workers at the Paducah Gaseous Diffusion Plant

Objective: The Paducah Gaseous Diffusion Plant (PGDP) became operational in 1952; it is located in the western part of Kentucky. We conducted a mortality study for adverse health effects that workers may have suffered while working at the plant, including exposures to chemicals. Materials and Methods: We studied a cohort of 6820 workers at the PGDP for the period 1953 to 2003; there were a total of 1672 deaths to cohort members. Trichloroethylene (TCE) is a specific concern for this workforce; exposure to TCE occurred primarily in departments that clean the process equipment. The Life Table Analysis System (LTAS) program developed by NIOSH was used to calculate the standardized mortality ratios for the worker cohort and standardized rate ratio relative to exposure to TCE (the U.S. population is the referent for age-adjustment). LTAS calculated a significantly low overall SMR for these workers of 0.76 (95% CI: 0.72-0.79). A further review of three major cancers of interest to Kentucky produced significantly low SMR for trachea, bronchus, lung cancer (0.75, 95% CI: 0.72-0.79) and high SMR for Non-Hodgkin\u27s lymphoma (NHL) (1.49, 95% CI: 1.02-2.10). Results: No significant SMR was observed for leukemia and no significant SRRs were observed for any disease. Both the leukemia and lung cancer results were examined and determined to refect regional mortality patterns. However, the Non-Hodgkin\u27s Lymphoma finding suggests a curious amplification when living cases are included with the mortality experience. Conclusions: Further examination is recommended of this recurrent finding from all three U.S. Gaseous Diffusion plants

A novel lineage of proteobacteria involved in formation of marine Fe-oxidizing microbial mat communities

© The Authors, 2007. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 2 (2007): e667, doi:10.1371/journal.pone.0000667.For decades it has been recognized that neutrophilic Fe-oxidizing bacteria (FeOB) are associated with hydrothermal venting of Fe(II)-rich fluids associated with seamounts in the world's oceans. The evidence was based almost entirely on the mineralogical remains of the microbes, which themselves had neither been brought into culture or been assigned to a specific phylogenetic clade. We have used both cultivation and cultivation-independent techniques to study Fe-rich microbial mats associated with hydrothermal venting at Loihi Seamount, a submarine volcano. Using gradient enrichment techniques, two iron-oxidizing bacteria, strains PV-1 and JV-1, were isolated. Chemolithotrophic growth was observed under microaerobic conditions; Fe(II) and Fe0 were the only energy sources that supported growth. Both strains produced filamentous stalk-like structures composed of multiple nanometer sized fibrils of Fe-oxyhydroxide. These were consistent with mineralogical structures found in the iron mats. Phylogenetic analysis of the small subunit (SSU) rRNA gene demonstrated that strains PV-1 and JV-1 were identical and formed a monophyletic group deeply rooted within the Proteobacteria. The most similar sequence (85.3% similarity) from a cultivated isolate came from Methylophaga marina. Phylogenetic analysis of the RecA and GyrB protein sequences confirmed that these strains are distantly related to other members of the Proteobacteria. A cultivation-independent analysis of the SSU rRNA gene by terminal-restriction fragment (T-RF) profiling showed that this phylotype was most common in a variety of microbial mats collected at different times and locations at Loihi. On the basis of phylogenetic and physiological data, it is proposed that isolate PV-1T ( = 1ATCC BAA-1019: JCM 14766) represents the type strain of a novel species in a new genus, Mariprofundus ferrooxydans gen. nov., sp. nov. Furthermore, the strain is the first cultured representative of a new candidatus class of the Proteobacteria that is widely distributed in deep-sea environments, Candidatus ζ (zeta)-Proteobacteria cl. nov.Funding was provided to DE and CLM by the National Science Foundation (0348330) and to DE through the NASA Astobiology Institute

Help-Seeking for Intimate Partner Violence and Forced Sex in South Carolina

Purpose: In this population-based, random-digit-dial, cross-sectional survey, we assessed the lifetime victimization of intimate partner violence (IPV) and forced or coerced sex among 556 women and men in South Carolina, and the help-seeking behaviors of victims. Results: Among women, 25.3% experienced IPV (sexual, physical, or emotional violence) compared with 13.2% of men. Although women were significantly more likely to report physical or sexual IPV (17.8%) than were men (4.9%), men (8.3%) were as likely as women (7.4%) to report perceived emotional abuse without physical or sexual IPV. One half of men and women with annual income