scholarly journals Combination of methods of thermal and radiation treatment of sediments associated with PCBs – the Delor type

Nukleonika ◽  
2021 ◽  
Vol 66 (4) ◽  
pp. 207-211
Author(s):  
Marko Fülöp ◽  
Andrea Šagátová ◽  
Ivan Benkovský ◽  
Karel Prokes ◽  
Lubica Foltinova
Keyword(s):  
Heat Treatment ◽  
Polychlorinated Biphenyls ◽  
Efficient Method ◽  
Radiation Treatment ◽  
Reduction Factor ◽  
Radiation Processing ◽  
Pcb Congeners ◽  
Fold Reduction ◽  
Dioxins And Furans ◽  
Combination Of Methods

Abstract An efficient method of burning polychlorinated biphenyls (PCBs) is often used to remove the environmental burden of PCBs. However, combustion produces toxic dioxins and furans (PCDD/F), so residents are increasingly rejecting this method. The heat treatment (HT) method does not burn PCBs but evaporates it from sediments. Even in this process, PCDD/Fs are formed to a lesser extent, which are destroyed by radiation processing (RP) following the HT. At the same time, the RP method degrades PCB congeners down to biphenyls, which decompose easily in the environment. A block assembly of a complex synergistic combination of equipment for methods of thermal (HT) and radiation (RP) destruction of PCBs in sediments is proposed. The efficacy of this complex was preliminarily determined at a level of 70-fold reduction in PCB concentration in sediments. To achieve a higher reduction factor in the concentration of PCBs, possible procedures for optimizing the settings of individual devices of this complex are presented.

scholarly journals Polychlorinated biphenyls and risk of hepatocellular carcinoma in the population living in a highly polluted area in Italy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Francesco Donato ◽  
Marco Moneda ◽  
Nazario Portolani ◽  
Angelo Rossini ◽  
Sarah Molfino ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Polychlorinated Biphenyls ◽  
Serum Levels ◽  
Polluted Area ◽  
Sufficient Evidence ◽  
Pcb Congeners ◽  
Non Hodgkin Lymphoma ◽  
And Gender ◽  
Few Data ◽  
Incident Cases

AbstractPolychlorinated biphenyls (PCBs) are human carcinogens, based on sufficient evidence for melanoma and limited evidence for non-Hodgkin lymphoma and breast cancer. Few data are available for liver cancer, although PCBs cause it in rats and determined liver damage in poisoned people. We investigated the association between PCB serum levels and hepatocellular carcinoma (HCC) with a case–control study in a PCB-polluted area in North Italy. We enrolled prospectively 102 HCC incident cases and 102 age and gender-matched hospital controls. Serum concentrations of 33 PCB congeners were determined by a gas chromatograph coupled to mass spectrometry. Of 102 HCC cases, 62 who had lost < 3 kg of body weight in past 3 years were included in the analysis (67.7% males, mean age 68 years). The odds ratio (OR) for HCC for 3rd compared to 1st tertile of PCB distribution was 1.76 (95% confidence interval 0.62–5.03) for total PCB, adjusting for socio-demographic variables and risk factors for HCC by logistic regression. For most PCB congeners, ORs > 1.5 or 2 were found, although the 95% CIs included the null value for almost all of them. This preliminary study suggests that PCBs might play a role in HCC development.

scholarly journals Bacterial degradation of a mixture of hydroxy- and metoxypolychlorinated biphenyls

2019 ◽  
Vol 486 (3) ◽  
pp. 307-311
Author(s):  
D. O. Egorova ◽  
T. I. Gorbunova ◽  
M. G. Pervova ◽  
K. A. Plotnikova ◽  
T. D. Kiryanova ◽  
...  
Keyword(s):  
Polychlorinated Biphenyls ◽  
Total Content ◽  
Bacterial Degradation ◽  
Specific Rate ◽  
Bacterial Transformation ◽  
Initial Concentration ◽  
Chemical Functionalization ◽  
Pcb Congeners ◽  
Total Absence ◽  
Rhodococcus Wratislaviensis

In this work, the possibility of combining the methods of chemical functionalization of a mixture of polychlorinated biphenyls before the formation of a mixture of hydroxy- and methoxy-chlorinated biphenyls and the bacterial transformation of the compounds obtained with the aim of their utilization was investigated. As a result of a 100% conversion, a mixture of compounds identified as methoxy- (30 compounds), hydroxy- (44 compounds) and methoxy (hydroxy) derivatives (47 compounds) was obtained by reacting a mixture of Sovol with MeONa in MeOH and DMSO. PCB congeners. The total content of all hydroxy derivatives was 77.2%. It was established that the strain Rhodococcus wratislaviensis KT112-7 carries out the destruction of 73-93% of this mixture at the initial concentration of 0.25-1.50 g/l. The best result was obtained with a decomposition of 0.1 g/l of a mixture of methoxy- and hydroxy-polychlorobiphenyls (on the 10th day the total absence of the starting compounds). The specific rate of destruction was in direct correlation with the initial concentration of the mixture. It has been shown that during bacterial transformation there is no accumulation of toxic intermediate compounds.

Perchlorination of Polychlorinated Biphenyls

1974 ◽  
Vol 57 (2) ◽  
pp. 416-417
Author(s):  
James N Huckins ◽  
Jerome E Swanson ◽  
David L Stalling
Keyword(s):  
Polychlorinated Biphenyls ◽  
Efficient Method ◽  
Antimony Pentachloride

Abstract A simple and efficient method for the perchlorination of polychlorinated biphenyls (PCBs) to decachlorobiphenyl, using antimony pentachloride, is described. Average yields of decachlorobiphenyl from 3 individual samples of Aroclors 1016 and 1254 were 85 and 104%, respectively. Bromine was identified as a contaminant in certain lots of antimony pentachloride. PCB perchlorinations with bromide-contaminated antimony pentachloride resulted in significant amounts of bromononachlorobiphenyl.

scholarly journals Determining the Dose of Radiation and Radurisation Effects on the Antioxidant Activity of Fish and the Thermophysical Characteristics of Fish Muscle Tissue

Foods ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 130
Author(s):  
Roza T. Timakova ◽  
Sergey L. Tikhonov ◽  
Nataliya V. Tikhonova ◽  
Sergey V. Shikhalev
Keyword(s):  
Antioxidant Activity ◽  
Electron Paramagnetic Resonance ◽  
Radiation Dose ◽  
Muscle Tissue ◽  
Radiation Treatment ◽  
Fish Muscle ◽  
Radiation Processing ◽  
Thermophysical Characteristics ◽  
Paramagnetic Resonance ◽  
Electron Paramagnetic

The aim of this article is to develop a method for determining the dose of radiation in the processing of chilled fish and its effect on the antioxidant activity and thermophysical characteristics of muscle tissue. Radiation processing of chilled fish was performed using a linear electron accelerator model LEA-10-10S2. The dose of radiation was determined by the method of electron-paramagnetic resonance. After being treated with ionizing radiation, the cooled fish meets the requirements of the technical regulations of TR TU 021/2011 “On food safety” and TR EAEU 040/2016 “On the safety of fish and fish products”. As a result of our research, a correlation was established between the area of the Electron Paramagnetic Resonance (EPR) signal and the absorbed dose of the radiation dose. We proved a decrease in the antioxidant activity of muscle tissue of fish with an increase in radiation dose. It is established that radiation treatment of chilled fish affects the thermophysical properties of muscle tissue.

The ecotoxicology of coplanar polychlorinated biphenyls

1995 ◽  
Vol 3 (2) ◽  
pp. 171-190 ◽  
Author(s):  
Christopher D. Metcalfe ◽  
G. Douglas Haffner
Keyword(s):  
Polychlorinated Biphenyls ◽  
Toxicity Tests ◽  
Molecular Configuration ◽  
Coplanar Pcbs ◽  
Toxic Activity ◽  
Pcb Congeners ◽  
Coplanar Polychlorinated Biphenyls ◽  
Toxic Equivalents

Polychlorinated biphenyls (PCBs) have been recognized for over 25 years as global environmental contaminants. However, many PCB congeners may be relatively harmless, while a small group of PCB congeners are highly toxic to biota. The toxic coplanar PCB congeners are chlorinated at meta positions and at one or none of the ortho positions on the biphenyl ring, thus resembling 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in molecular configuration. In vitro and in vivo toxicity tests with rodents, fish, and birds have shown that the coplanar PCB congener 126 is almost as toxic as TCDD. Several coplanar PCBs (e.g., 77, 126, 105, 118) are present in biota at parts per billion concentrations, which is orders of magnitude higher than concentrations of TCDD. Thus, coplanar PCBs may account for over 95% of the dioxinlike toxic activity affecting biota, such as fish-eating birds in the Great Lakes. There is some evidence that the toxicokinetics of coplanar PCBs in organisms differs from that of other PCB homologues. If coplanar PCBs are more persistent than their homologues, they could become enriched in biota as they pass up through the food chain (i.e., trophic enrichment), or as overall PCB levels decline with time (i.e., temporal enrichment). Overall, the available data do not support the concept of trophic or temporal enrichment in the environment.Key words: polychlorinated biphenyls, coplanar, toxic equivalents, kinetics, mixed function oxidase, 7-ethoxyresorufin-O-deethylase.

scholarly journals Radiation processing for cultural heritage preservation – Romanian experience

Nukleonika ◽  
2017 ◽  
Vol 62 (4) ◽  
pp. 253-260 ◽  
Author(s):  
Ioan Valentin Moise ◽  
Mihaela Ene ◽  
Constantin Daniel Negut ◽  
Mihalis Cutrubinis ◽  
Maria Mihaela Manea
Keyword(s):  
Ionizing Radiation ◽  
Cultural Heritage ◽  
Radiation Treatment ◽  
General Rule ◽  
Research Programme ◽  
Storage Conditions ◽  
Radiation Sterilization ◽  
Radiation Processing ◽  
Widespread Application ◽  
Cellulose Pulp

Abstract Radiation sterilization has been considered a mass decontamination technique for biodegradable cultural heritage (CH) since its widespread application in the medical field. Initial experiments have revealed advantages, for example, efficiency and effectiveness, but also disadvantages, namely “side effects” concerning CH materials. More than 50 years later, the adequacy of ionizing radiation for some CH artefacts is still the subject of discussion. The main reason why is that science and industry are not yet able to provide a more efficient technique for treating mass decontamination. For wooden items, there is general agreement that the irradiation dose required for insect eradication is not damaging, even in the case of polychromed wood. For cellulose pulp (paper), there is a reduction in polymerization degree (DP) at the high doses necessary to stop the attack of fungi, but this should be considered taking into account the purpose of the treatment. Emergency or rescue treatments are necessary to mitigate the consequences of accidents or improper storage conditions. In some cases (archives), the value of written information is greater than the historical value of the paper support. For other materials, namely textiles, leather and parchment, less research has been published on the effect of ionizing radiation treatment. As a general rule, irradiation is not necessary when only a few CH elements are present that are affected by biological contamination since restorers can solve the problem by classical means. The need for radiation treatment arises when large collections (hundreds, thousands or even more elements) are heavily affected by the biological attack. In Romania, the IRASM gamma irradiator of IFIN-HH is receiving an increasing number of requests for CH treatment, mainly due to an intensive research programme concerning this topic and close liaison with CH owners or administrators. Besides reviewing the scientific results obtained in Romania and abroad, this paper presents some examples from experiences in Romania.

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