scholarly journals P,p′-DDT and p,p′-DDE in Blood Samples of Occupationally Exposed Workers: Community Studies on Pesticides, Dade County, Fla.

1969 ◽  
Vol 84 (1) ◽  
pp. 53 ◽  
Author(s):  
Walter F. Edmundson ◽  
John E. Davies ◽  
Gigi A. Nachman ◽  
Robert L. Roeth
2008 ◽  
Vol 65 (8) ◽  
pp. 613-618 ◽  
Author(s):  
Branka Djurovic ◽  
Vesna Spasic-Jokic ◽  
Branislav Djurovic

Background/Aim. During exposure to low-level doses (LLD) of ionizing radiation (IR), the most of harmful effects are produced indirectly, through radiolysis of water and formation of reactive oxygen species (ROS). The antioxidant enzymes - superoxide dismutase (SOD): manganese SOD (MnSOD) and copper-zinc SOD (CuZnSOD), as well as glutathione (GSH), are the most important intracellular antioxidants in the metabolism of ROS. Overproduction of ROS challenges antioxidant enzymes. The aim of this study was to examine if previous exposure to low doses of IR induces adaptive response by means of stimulation of intracellular antioxidant defense system. Methods. We investigated a group of medical workers occupationally exposed to IR (n = 44), 29 male and 15 female. The controls (n = 33) consisted of medical workers not exposed to IR, 23 male and 10 female. The examinees from both groups worked in the same environment and matched in crucial characteristics. All measurements were performed by a calibrated thermoluminiscent dosimeter type CaF2:Mn. SOD activity and GSH content were measured spectrophotometrically in the plasma of both groups of medical workers. Half of each blood sample was irradiated by 2Gy of ? radiation, dose-rate 0.45 Gy/min, and the distance from the source of 74 cm. Results. The dosimetry results indicate that occupational doses were very low. Our results confirmed significantly higher SOD activity in the exposed vs. unexposed workers (p < 0.00006). SOD activity after irradiation of blood samples failed to show a significant difference between the exposed workers and the controls (p = 0.905), even the difference in each group before and after the irradiation was significant. In blood samples of the exposed workers expression of enzymes after the irradiation, was not as high as in the controls, or even in the case of the exposed in nuclear medicine personnel, SOD activity was decreased. There were no significant differences in the content of GSH between the groups. Conclusion. Our results pointed out that occupational exposure to low doses of IR compromised mitochondrial function. During occupational exposure, the activity of antioxidant enzymes was increased as a protection against the increased production of ROS. After high-dose irradiation dysfunction of mitochondrial system was noticed, suggesting the break-down of antioxidant defense and failure of an adaptive response. Therefore, the "chronic oxidative stress" might reduce antioxidant defense in the case of accidental exposure to high doses of IR. It could indirectly increase the incidence of some other "free radicals' diseases" in occupationally exposed personnel. .


Author(s):  
Mohamed Anouar Nouioui ◽  
Manel Araoud ◽  
Marie-Laure Milliand ◽  
Frédérique Bessueille-Barbier ◽  
Dorra Amira ◽  
...  

1984 ◽  
Vol 41 (4) ◽  
pp. 533-538 ◽  
Author(s):  
A Mutti ◽  
M Falzoi ◽  
S Lucertini ◽  
G Arfini ◽  
M Zignani ◽  
...  

2017 ◽  
Vol 37 (9) ◽  
pp. 901-908 ◽  
Author(s):  
AM Samir ◽  
LA Rashed

Aim: The aim of this work was to investigate the relationships between aluminium levels, oxidative status and DNA damage in workers occupationally exposed to aluminium. Subjects and methods: This study was conducted in a secondary aluminium smelter. It included 96 male workers occupationally exposed to aluminium fume and dust compared to 96 male nonexposed individuals. Full history and clinical examination were done for all participants. Laboratory investigations in the form of serum aluminium, total antioxidant capacity (TAC), urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) and comet assay test were performed. Results: Serum aluminium level ranged from 4 to 30 µg/L of median: 10 µg/L; urinary 8-OHdG ranged from 2.7 to 17.2 ng/mg creatinine of median: 7.6 ng/mg creatinine; comet tail length (CTL) ranged from 19.7 to 50.5 µm of median: 45 µm, were statistically significantly increased in the exposed group compared to nonexposed group. In exposed workers, a statistically significant positive correlations were found between serum aluminium level and urinary 8-OHdG ( r = 0.75, p < 0.001); aluminium level and CTL ( r = 0.71, p < 0.001); and urinary 8-OHdG and CTL ( r = 0.71, p < 0.001). There was a statistically significant negative correlation between serum aluminium and TAC ( r = −0.76, p < 0.001). Conclusion: Occupational exposure to aluminium in secondary aluminium smelters was related to the induction of oxidative stress and DNA damage. This may promote the development of adverse health hazards in the exposed workers


2014 ◽  
Vol 37 (1) ◽  
pp. 267-274 ◽  
Author(s):  
Teodorico Casale ◽  
Tiziana Caciari ◽  
Maria Valeria Rosati ◽  
Pier Agostino Gioffrè ◽  
Maria Pia Schifano ◽  
...  

2018 ◽  
Vol 183 (4) ◽  
pp. 503-513 ◽  
Author(s):  
Tae Young Kong ◽  
Gamal Akabani ◽  
John W Poston

Abstract One of the most important issues in the nuclear power industry is the implementation of the 2007 Recommendations of the International Commission on Radiological Protection (ICRP) published in ICRP Publication 103. These recommendations include the implementation of the concept of dose constraints for occupationally exposed workers at nuclear power plants (NPPs). When considering these changes from a cost–benefit standpoint, the implementation of dose constraints is still highly controversial. This study analysed annual occupational dose distributions to determine whether a dose constraint is needed for occupationally exposed workers at the US NPPs. Results of the analysis showed that the use of dose constraints had no positive impact on radiation safety of workers at NPPs in the USA. In fact, it appears that the implementation of dose constraints will impose an unnecessary regulatory burden on licensees. Based on these results, implementation of dose constraints is not recommended.


2021 ◽  
Vol 53 (1) ◽  
pp. 351-356
Author(s):  
Tae Young Kong ◽  
Si Young Kim ◽  
Yoonhee Jung ◽  
Jeong Mi Kim ◽  
Moonhyung Cho

Antioxidants ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 12 ◽  
Author(s):  
Iman M. Ahmad ◽  
Maher Y. Abdalla ◽  
Tiffany A. Moore ◽  
Lisa Bartenhagen ◽  
Adam J. Case ◽  
...  

Studies have shown an increased risk for a variety of cancers, specifically brain cancer, in healthcare workers occupationally exposed to ionizing radiation. Although the mechanisms mediating these phenomena are not fully understood, ionizing radiation-mediated elevated levels of reactive oxygen species (ROS), oxidative DNA damage, and immune modulation are likely involved. A group of 20 radiation exposed workers and 40 sex- and age-matched non-exposed control subjects were recruited for the study. We measured superoxide (O2•−) levels in whole blood of healthcare workers and all other measurements of cytokines, oxidative DNA damage, extracellular superoxide dismutase (EcSOD) activity and reduced/oxidized glutathione ratio (GSH/GSSG) in plasma. Levels of O2•− were significantly higher in radiation exposed workers compared to control. Similarly, a significant increase in the levels of interleukin (IL)-6, IL-1α and macrophage inflammatory protein (MIP)-1α in radiation exposed workers compared to control was observed, while there was no significance difference in the other 27 screened cytokines. A significant positive correlation was found between MIP-1α and O2•− levels with no correlation in either IL-6 or IL-1α. Further, a dose-dependent relationship with significant O2•− production and immune alterations in radiation exposed workers was demonstrated. There was no statistical difference between the groups in terms of oxidative DNA damage, GSH/GSSG levels, or EcSOD activity. Although the biologic significance of cytokines alterations in radiation exposed workers is unclear, further studies are needed for determining the underlying mechanism of their elevation.


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