scholarly journals Hyperhomocysteinemia in children and forest fires in the Chоrnobyl exclusion zone

2020 ◽  
pp. 21-26
Author(s):  
Yu.I. Bandazhevsky ◽  
◽  
N.F. Dubova ◽  

Objective: We determined a role of folate metabolism genotypes in the occurrence of hyperhomocysteinemia in children after a forest fire in the Chоrnobyl exclusion zone (ChEZ). Material and methods: In the study, we applied immunochemical, Real-time PCR, mathematical and statistical methods. Results: A survey of 84 adolescents from the Poliske district, Kiev region revealed changes in their metabolic processes in the form of increased homocysteine production in connection with a forest fire in the ChEZ which was recorded during April 26-29, 2015. A comparative analysis of the specific gravity of the folate cycle genotypes in the subgroups of the children with hyperhomocysteinemia before and after a forest fire showed that an endogenous factor in the form of a genetic apparatus, controling synthesis of folate cycle enzymes, was not involved in this phenomenon. Сonclusions: Forest and peat fires in the Chernobyl exclusion zone are one of the main causes for the elevation in blood homocysteine levels in children from the adjacent districts, regardless of the state of folate metabolism genetic system. Monitoring of the blood homocysteine levels in children and adults living under conditions of the exposure to wood combustion gases, containing radioactive elements, is a key component of the programmer for the prevention of cancer and cardiovascular diseases.

2020 ◽  
Vol 1 (154) ◽  
pp. 333-338
Author(s):  
S. Azarov ◽  
R. Shevchenko ◽  
S. Shcherbak

The paper deals with the problem of formation of general procedures for experimental study of environmental impact due to forest fire in complex radiation conditions of fire load formation and its further testing on the example of the ChNPP exclusion zone. The study carried out an experimental verification of the adequacy of the previously proposed methodological apparatus and identified the main directions of its further use as a basis for solving the problems of predicting the negative environmental impact on the environment. To this end, the following tasks have been solved:the general procedures of the methodology of experimental study of environmental impact due to forest fire in complex radiation conditions of fire load formation are formulated; a comprehensive experimental study was carried out using the developed method on the example of the fire load of the Chernobyl exclusion zone. Conducted studies in the field indicate that the content of radioactive smoke in the ground atmosphere of the Exclusion Zone can be dramatically increased by several orders of magnitude due to forest fires. Short-term (sever-al days) increased content of radioactive combustion products in the surface air can reach the level of radiation hazard for both the environment and directly for the life of the population living in a clean area at considerable distances (up to 30 km along the track axis) wildfire. The fires in the forests contaminated with Chornobyl radionuclide in the western trace due to the loss of TUE are of particular environmental danger, since the presence of plutonium combustion products in radioactive products results in significant dose loads for the environment and the population. The practical significance of the obtained results lies in the possibility of their application for carrying out complex ecological audit of the territory, which is subject to secondary radiation influence both inside and outside the exclusion zone of the Chornobyl NPP. Keywords: ecological safety, forest fire, radiation exposure, complex fire load


2021 ◽  
pp. 11-18
Author(s):  
Yu.I. Bandazhevskyi ◽  
◽  
N. F. Dubova ◽  

Objective We performed a comparative assessment of the blood levels of homocysteine, pituitary and thyroid hormones in children with different levels of physical development before and after forest fires in the Chornobyl exclusion zone (ChEZ) in 2015. Methods: We used immunochemical, instrumental, mathematical and statistical methods. Results: The analysis of variable dynamics was performed in 336 adolescents of the Polisskyi and the Ivankivskyi districts of Kyiv region. An association was found between homocysteine (Нсу), hormones of the pituitary-thyroid axis and physical development of children. A statistically significantly higher level of Нсу was observed in the adolescents from the Ivankivskyi district in comparison with the children from the Polisskyi district. Forest fires in the spring and summer of 2015 in the ChEZ should be considered the main cause for the increase in Нсу in the blood of the adolescents. The increased level of Т3 in the peripheral tissues induced by Нсy and TSH contributed to a decrease in the physical development index values. Due to a decrease in the intensity of the Т4 deiodination process, the insufficient formation of Т3 in the peripheral tissues was recorded in the group of children with a disharmonious high physical development.


2021 ◽  
Vol 94, 2021 (94) ◽  
pp. 35-43
Author(s):  
Andriy Babushka ◽  
◽  
Lyubov Babiy ◽  
Borys Chetverikov ◽  
Andriy Sevruk ◽  
...  

Earth remote sensing and using the satellite images play an important role when monitoring the effects of forest fires and assessing damage. Applying different methods of multispectral space images processing, we can determine the risk of fire distribution, define hot spots and determine thermal parameters, mapping the damaged areas and assess the consequences of fire. The purpose of the work is the severity assessment connected with the post-fire period on the example of the forests in the Chornobyl Exclusion Zone. The tasks of the study are to define the area of burned zones using space images of different time which were obtained from the Sentinel-2 satellite applying the method of a normalized burn ratio (NBR) and method of supervised classification. Space images taken from the Sentinel-2 satellite before and after the fire were the input data for the study. Copernicus Open Access Hub service is a source of images and its spatial resolution is 10 m for visible and near infrared bands of images, and 20 m for medium infrared bands of images. We used method of Normalized Burn Ratio (NBR) and automatically calculated the area damaged with fire. Using this index we were able to identify areas of zones after active combustion. This index uses near and middle infrared bands for the calculations. In addition, a supervised classification was performed on the study area, and signature files were created for each class. According to the results of the classification, the areas of the territories damaged by the fire were also calculated. The scientific novelty relies upon the application of a method of using the normalized combustion coefficient (NBR) and supervised classification for space images obtained before and after the fire in the Chernobyl Exclusion Zone. The practical significance lies in the fact that the studied methods of GIS technologies can be used to identify territories and calculate the areas of vegetation damaged by fires. These results can be used by local organizations, local governments and the Ministry of Emergency Situations to monitor the condition and to plan reforestation. The normalized burned ratio (NBR) gives possibility efficiently and operatively to define and calculate the area which were damaged by fires, that gives possibility operatively assess the consequences of such fires and estimate the damage. The normalized burned ratio allows to calculate the area of burned forest almost 2 times more accurately than the supervised classification. The calculation process itself also takes less time and does not require additional procedures (set of signatures). Supervised classification in this case gives worse accuracy, the process itself is longer, but allows to determine the area of several different classes.


2010 ◽  
Vol 161 (11) ◽  
pp. 442-449 ◽  
Author(s):  
Thomas Zumbrunnen ◽  
Matthias Bürgi ◽  
Harald Bugmann

Forest fire regimes are particularly sensitive to variations in the climate and to human influences. In the Alps both the manner in which the land is used and climatic changes, in particular rises in temperature and the frequency of drought periods, are probably going to bring about considerable modifications in fire regimes. The history of these fires in Valais in the 20th century is however still little known, as is the influence of the different determining factors. From a study of documentary archives we have therefore reconstituted the history of forest fires in Valais from 1904 to 2008. We then tried to establish whether or not the fire regime had evolved during this time by comparing descriptive statistics from the first and the second halves of the period under study. By means of correlation analyses we could then find what factors had a significant influence on the occurrence of fires. What emerges is that forest fire activity moved towards the plain in the course of the 20 century, probably on account of the increase in population density at lower altitudes. The seasonality of the fires also evolved: there was an outbreak of fires in the spring during the second half of the period under study, whereas in the first half fires mostly occurred in summer. On the other hand the frequency of the fires and the surface area burned annually did not differ significantly in the periods before and after 1955. As for the balance between factors determining the frequency of fires and the surface burned annually, there has been a modification in the period under study. Although drought was a decisive factor in the first decades of the 20 century, afterwards it seems to have declined in importance, being supplanted by other factors, notably the availability of combustible material. The fact that at present the forest fire regime is apparently regulated by factors other than the climate means it is possible to envisage concrete measures in order to limit fire risks.


Author(s):  
D. Bazyka ◽  
◽  
P. Fedirko ◽  
V. Vasylenko ◽  
O. Kolosynska ◽  
...  

Objective.of this study was to determine the levels of radionuclides in the rescuers’ bodies of the SES during firefighting in the exclusion zone of the Chornobyl nuclear power plant and to assess the dose of internal radiation due to this receipt. Materials and methods. From 06.04.2020 to 19.05.2020 in the State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine» (NRCRM) measurements of the content of incorporated gamma radionuclides on whole body counters (WBC) operational class «Screener-3M» (Minimum detected activity (MDA) is 300–500 Bq for 5 minutes of measurement at 137Cs) and expert high-sensitivity WBC (MDA is 20 Bq for 10 minutes of measurement at 137Cs). 470 people (523 measurements) in three groups of personnel of the SES of Ukraine who took part in the forest fire liquidation in the exclusion zone in the period from April 4 to May 5, 2020 were examined. Mathematical and spectrometric methods are used in the work. Results and conclusions. In the vast majority (95 %) of the personnel of the SES of Ukraine, examined at the WBC operational class «Screener-3M» (more than 500 measurements), the assessment of the values of the individual effective dose of internal radiation due to 137Cs in the body during firefighting, assuming that it receipt occurred during operation in the exclusion zone, did not exceed the minimum dose detected by MDD (5–14 μSv). The average value of the effective dose of internal radiation in the group of personnel of the State Emergency Service of Ukraine in Kyiv, which participated in the elimination of forest fires in the exclusion zone from April 4 to May 5, 2020 (26 people) studied at the expert WBC, is 2.5 ± 1.1 μSv, in the group of personnel of the SES of Ukraine in Cherkasy region, which participated in the fire on April 19–24, 2020 (9 people) – 2.2 ± 0.6 μSv, in the group of personnel of the SES of Ukraine in the Kyiv region, which took part in the elimination of the forest fire in the exclusion zone on April 4 – May 5, 2020 (42 people) – 4.4 ± 2.4 μSv. Maximum values of 5.1 μSv, 3.5 μSv, 11.8 μSv in the groups of Kyiv city, Cherkasy and Kyiv regions, respectively, which is much lower than the basic dose limit for the population from man-made sources of 1000 μSv · year-1 according to the Law of Ukraine about protection of the person against influence of ionizing radiation. Key words: forest fire, Chornobyl Exclusion Zone, internal irradiation, whole body counters, 137Сs.


2021 ◽  
Vol 100 (3) ◽  
pp. 30-37
Author(s):  
Yu.I. Bandazhevskyi ◽  
◽  
N.F. Dubova ◽  

Objective: The aim of the study was to identify interrelations between the state of folate cycle genetic apparatus and blood levels of homocysteine, thyroid and adenohypophysis hormones in the blood among the children from Ivankivskyi and Poliskyi districts, Kyiv region, bordering the Chornobyl exclusion zone (СhEZ). Methods: Immunochemical, genetic, statistical ones. Results: We measured blood levels of homocysteine (Hcy), pituitary thyroid-stimulating hormone (TSH), free triiodothyronine (T3), free thyroxine (T4) in 158 children from Poliskyi district and 178 children from Ivankivskyi district and assessed the state of a genetic system of the folate cycle (FC). The average age of the examined was (15.2 ± 0.9) years old (95% CI 15.0-15.4 years old). Taking into account the FC genotypes, genetic subgroups were formed, they were based on 100% representation of one specific genotype. The laboratory examination was carried out twice: in April and December 2015 (before and after the fires in the ChEZ). It was found out that in the total group of the children, as well as in most of analyzed genetic subgroups, the level of Hcy and thyroid hormones (TG) in the children from Ivankivskyi district was statistically significantly higher than in those from Poliskyi district. At the same time, a direct association between Hcy and TSH was observed in the total group, as well as in most of the genetic subgroups of children from Ivankivskyi district, and this ssociation was absent in the children from Poliskyi district. The blood level of Hcy both in the children from Poliskyi district and in the children from Ivankivskyi district was statistically significantly higher in the subgroup containing only homozygous variants of the T allele of the MTHFR:677 genetic polymorphism in comparison with the subgroups containing neutral C alleles of the same polymorphism. At the same time, there were no differences for TSH, T3 and T4. Сonclusions: The analysis enabled to establish a synchronous reaction of metabolic cycles ensuring the metabolism of Hcy and thyroid hormones in the adolescents, regardless of the FC genotypes. Correlation analysis, as well as the results of statistical analysis, indicate that an increase in the level of Hcy in the blood of children induced the synthesis of TSH and T3. The results show a close relationship between thyroid hormone genesis and the metabolism of methionine sulfur-containing amino acids and Hcy. A forest fire, containing long-lived radioactive elements, is the most likely reason for the increase of Hcy level and, as a result, the hormones of the pituitary-thyroid axis in the blood of the children living in the districts, bordering the ChEZ.


2020 ◽  
Vol 27 ◽  
pp. 179-184
Author(s):  
Yu. I. Bandazhevsky ◽  
N. F. Dubovaya

Fires that often occur in the forests of the Chernobyl Exclusion Zone are one of the most powerful sources of secondary air contamination with combustion products and various radionuclides that have a negative effect on the health of children and adults. Aim. Aim was to explore the relationship between forest fires and the change in blood homocysteine levels in children living in Polessky district of Ukraine bordering the Chernobyl Exclusion Zone. Methods. Immunochemical, mathematical and statistical. Results. Increased blood levels of homocysteine, irrespective of the state of genome of folate cicle, were found in more than 70.0 % of cases in the group of children living near the Chernobyl Exclusion Zone during the period from 02/04/2015 to 18/12/2015. Given the forest fires with an area of 10.127 ha and 130 ha officially registered in the Chernobyl exclusion zone in the spring and summer of 2015, it can reasonably be argued that the increase in the level of homocysteine in the blood of children living in the border region associatared with wood burning particles, including black carbon and radioactive elements, that enter the body with air and food. Conclusions. Forest fires in the Chernobyl Exclusion Zone are the cause of abnormal methionine metabolism and an increase in blood homocysteine levels in children from the adjacent districts. Keywords: homocysteine, folate metabolism, genetic polymorphisms, association, forest fires, Chernobyl Exclusion Zone.


Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 768
Author(s):  
Jin Pan ◽  
Xiaoming Ou ◽  
Liang Xu

Forest fires are serious disasters that affect countries all over the world. With the progress of image processing, numerous image-based surveillance systems for fires have been installed in forests. The rapid and accurate detection and grading of fire smoke can provide useful information, which helps humans to quickly control and reduce forest losses. Currently, convolutional neural networks (CNN) have yielded excellent performance in image recognition. Previous studies mostly paid attention to CNN-based image classification for fire detection. However, the research of CNN-based region detection and grading of fire is extremely scarce due to a challenging task which locates and segments fire regions using image-level annotations instead of inaccessible pixel-level labels. This paper presents a novel collaborative region detection and grading framework for fire smoke using a weakly supervised fine segmentation and a lightweight Faster R-CNN. The multi-task framework can simultaneously implement the early-stage alarm, region detection, classification, and grading of fire smoke. To provide an accurate segmentation on image-level, we propose the weakly supervised fine segmentation method, which consists of a segmentation network and a decision network. We aggregate image-level information, instead of expensive pixel-level labels, from all training images into the segmentation network, which simultaneously locates and segments fire smoke regions. To train the segmentation network using only image-level annotations, we propose a two-stage weakly supervised learning strategy, in which a novel weakly supervised loss is proposed to roughly detect the region of fire smoke, and a new region-refining segmentation algorithm is further used to accurately identify this region. The decision network incorporating a residual spatial attention module is utilized to predict the category of forest fire smoke. To reduce the complexity of the Faster R-CNN, we first introduced a knowledge distillation technique to compress the structure of this model. To grade forest fire smoke, we used a 3-input/1-output fuzzy system to evaluate the severity level. We evaluated the proposed approach using a developed fire smoke dataset, which included five different scenes varying by the fire smoke level. The proposed method exhibited competitive performance compared to state-of-the-art methods.


2021 ◽  
Vol 13 (1) ◽  
pp. 432
Author(s):  
Aru Han ◽  
Song Qing ◽  
Yongbin Bao ◽  
Li Na ◽  
Yuhai Bao ◽  
...  

An important component in improving the quality of forests is to study the interference intensity of forest fires, in order to describe the intensity of the forest fire and the vegetation recovery, and to improve the monitoring ability of the dynamic change of the forest. Using a forest fire event in Bilahe, Inner Monglia in 2017 as a case study, this study extracted the burned area based on the BAIS2 index of Sentinel-2 data for 2016–2018. The leaf area index (LAI) and fractional vegetation cover (FVC), which are more suitable for monitoring vegetation dynamic changes of a burned area, were calculated by comparing the biophysical and spectral indices. The results showed that patterns of change of LAI and FVC of various land cover types were similar post-fire. The LAI and FVC of forest and grassland were high during the pre-fire and post-fire years. During the fire year, from the fire month (May) through the next 4 months (September), the order of areas of different fire severity in terms of values of LAI and FVC was: low > moderate > high severity. During the post fire year, LAI and FVC increased rapidly in areas of different fire severity, and the ranking of areas of different fire severity in terms of values LAI and FVC was consistent with the trend observed during the pre-fire year. The results of this study can improve the understanding of the mechanisms involved in post-fire vegetation change. By using quantitative inversion, the health trajectory of the ecosystem can be rapidly determined, and therefore this method can play an irreplaceable role in the realization of sustainable development in the study area. Therefore, it is of great scientific significance to quantitatively retrieve vegetation variables by remote sensing.


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