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INTRODUCTION: Although the use of68Ga has increased substantially in nuclear medicine over the last decade, there is limited information available on occupational exposure due to68Ga. The purpose of this study is to determine the occupational extremity exposure during the preparation, dispensing and administration of68Ga-labelled radiopharmaceuticals. METHOD: Workers in eight centres wore a ring dosimeter for all tasks involving68Ga-labelled radiopharmaceuticals for a minimum of one month. Additionally, the fingertip dose was monitored in two centres and the hand with the highest ring dose during68Ga procedures was also identified in one centre. RESULTS: The median normalised ring dose for68Ga procedures was found to be 0.25 mSv GBq-1(range 0.01-3.34). The normalised68Ga ring doses recorded in this study are similar to that found in the literature for18F. This study is consistent with previous findings that the highest extremity dose is found on the non-dominant hand. A limited sub study in two of the centres showed a median fingertip to base of the finger dose ratio of 4.3. Based on this median ratio, the extrapolated annual68Ga fingertip dose for 94% of the workers monitored in this study would be below Category B dose limit (150 mSv) and no worker would exceed Category A dose limit (500 mSv). CONCLUSION: When appropriate shielding and radiation protection practices are employed, the extremity dose due to68Ga is comparable to that of18F and is expected to be well below the regulatory limits for the majority of workers.
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Exposição Ocupacional , Compostos Radiofarmacêuticos , Humanos , Projetos Piloto , Preparações Farmacêuticas , Dedos , Tomografia por Emissão de Pósitrons , Exposição Ocupacional/análise , Doses de RadiaçãoRESUMO
The dose limit for the skin of the hand is typically converted to a surface of 1 cm2, which means that one needs to measure point doses in different places on the hand. However, the commonly used method of measuring doses on the hand, i.e., using a dosimetric ring including one or several thermoluminescent detectors worn at the base of a finger, is not adequate for manual procedures such as labeling or radiopharmaceutical injection. Consequently, the purpose of this study was to create and conduct a series of computer simulations that, by recreating the actual working conditions, would provide information on the values of ionizing radiation doses received by the most exposed parts of the hands of employees of radiopharmaceutical production facilities, as well as those of nurses during the injection of radiopharmaceuticals. The simulations were carried out using Monte Carlo radiation transport calculations. The Hp(0.07) personal dose equivalent values obtained for the fingertips of the index and middle fingers of nursing staff and chemists were within the range limited by the minimum and maximum Hp(0.07) values obtained as a result of dosimetric measurements carried out in diagnostic and production centers. Only in the case of the nurse's fingertip, the simulated value of Hp(0.07 slightly exceeded the measured maximum Hp(0.07) value. The comparison of measured and simulated dose values showed that the largest differences in Hp(0.07) values occurred at the thumb tip, and for ring finger and middle finger of some of the nurses investigated.
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Fluordesoxiglucose F18 , Exposição Ocupacional/análise , Doses de Radiação , Exposição à Radiação/análise , Radiação Ionizante , Compostos Radiofarmacêuticos , Algoritmos , Simulação por Computador , Feminino , Mãos , Humanos , Método de Monte Carlo , Enfermeiras e Enfermeiros , Tomografia por Emissão de Pósitrons , PeleRESUMO
A major disadvantage of dose reconstruction by means of thermoluminescence (TL) is the fact that during readout of any TL material exposed to ionizing radiation (i.e., during measuring the glow curve), the radiation-induced signal gets lost. Application of the photo-transferred thermoluminescence phenomenon (PTTL) may offer a solution to this problem. In PTTL, the residual signal that is not destroyed by conventional TL readout (because it comes from deeper electron traps) can be readout through simultaneous stimulation by UV light and heating, allowing to obtain information about the absorbed dose in a second run. The present paper describes the application of PTTL for emergency dose assessment. For this, MTS-N thermoluminescent detectors (LiF: Mg, Ti) were exposed using a high-energy Clinac 2300 medical linear accelerator to doses of 100 mGy, 300 mGy, 500 mGy, 700 mGy and 1000 mGy. Irradiation with UV radiation allowed the determination of the optimal heating time of 3 h, while the optimal temperature was identified to be 70 °C. The results obtained demonstrated the usefulness of the PTTL method for emergency dose assessment. The efficiency of the PTTL method was determined as 19%. Finally it was found that the detector background after UV exposure should not be underestimated during routine dose measurements.
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Dosimetria Termoluminescente/métodos , Aceleradores de Partículas , Temperatura , Raios UltravioletaRESUMO
BACKGROUND: Proper management of bee pastures is considered an important activity for diversity of pollinators and conservation of the population size. In the present study, the floral composition and diversity, flowering spectrum and availability of food resources in natural and man-made habitats in four rural municipalities in Lublin Upland, SE Poland were evaluated. The connection between pollinator-friendly biotopes was also determined and some suggestions are made on creation/supplementation of bee pastures adapted to the arable land structure in eastern Poland (mean acreage 7.65 ha). RESULTS: Forage species richness (S) differed among vegetation types: the highest S value was found in field margins, while mixed forests represented the lowest species richness (mean ± standard deviation = 37.8 ± 9.5 vs 16.5 ± 2.3). In all habitats, the most abundant flowering was recorded in May. Then the blooming abundance decreased until a complete decline at the end of summer. The mean distance between pollinator-friendly biotopes is 2.4 ± 1.53 km, which is out of the flying range/foraging distance of most pollinators. CONCLUSION: Shortages of nectar and pollen resources in the agricultural landscape of SE Poland are evident. Therefore it is assumed that the landscape structure requires support in terms of food niches for pollinators and creation/supplementation of bee pastures is necessary, e.g. six to nine patches of 0.025-0.3 ha each within an area of 100 ha. © 2017 Society of Chemical Industry.
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Abelhas/fisiologia , Flores/química , Agricultura , Animais , Ecossistema , Flores/classificação , Polônia , PolinizaçãoRESUMO
Decreasing the individual dose limit of exposure to ionizing radiation to the eye lenses means verifying the need for routine monitoring of the eye lenses of workers exposed to ionizing radiation, including those employed in facilities producing radiopharmaceuticals based on short-lived isotopes. This work analyzes the exposure of the eye lenses of employees of centers that produce the isotopes for positron emission tomography, in particular fluorine-18. It takes into account the employment structure and work system of the discussed centers, including in terms of changing the dose limit of exposure to the eye lenses. This work complements the paper by Wrzesien (2018 Australas. Phys. Eng. Sci. Med. submitted) , which focused on the exposure of workers' hands to ionizing radiation in radiopharmaceutical production centers. Measurements were carried out using high-sensitivity thermoluminescence detectors (LiF: Mg, Cu, P-MCP-N). The measurements covered 17 employees. Our results show that the highest values of personal dose equivalent Hp(3) were recorded for the 18F-FDG quality control personnel and nurses who injected the radiopharmaceutical in the patients. In the group of nurses, the maximum daily does Hp(3) reached a value close to 200 µSv. For staff who performed the quality control of the 18F-FDG, the maximum daily dose of Hp(3) exceeded 200 µSv. The estimated annual exposure of the eye lenses of workers in these two occupational groups may exceed the new dose limit (20 mSv/year). Results of this study indicate the need for optimization of the procedures related to quality control of radiopharmaceuticals and the injection of 18F-FDG in patients.
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BACKGROUND: A radiopharmaceutical is a combination of a non-radioactive compound with a radioactive isotope. Two isotopes: technetium-99m (99mTc) and fluorine-18 (18F) are worth mentioning on the rich list of isotopes which have found numerous medical applications. Their similarity is limited only to the diagnostic area of applicability. The type and the energy of emitted radiation, the half-life and, in particular, the production method demonstrate their diversity. The 99mTc isotope is produced by a short-lived nuclide generator - molybdenum-99 (99Mo)/99mTc, while 18F is resulting from nuclear reaction occurring in a cyclotron. A relatively simple and easy handling of the 99Mo/99mTc generator, compared to the necessary use a cyclotron, seems to favor the principle of optimizing the radiological protection of personnel. The thesis on the effect of automation of both the 18F isotope production and the deoxyglucose labelling process on the optimization of radiological protection of workers compared to manual procedures during handling of radiopharmaceuticals labelled with 99Tc need to be verified. MATERIAL AND METHODS: Measurements of personal dose equivalent Hp(0.07) were made in 5 nuclear medicine departments and 2 radiopharmaceuticals production centers. High-sensitivity thermoluminescent detectors (LiF: Mg, Cu, P - MCP-N) were used to determine the doses. RESULTS: Among the activities performed by employees of both 18F-fluorodeoxyglucose (18F-FDG) production centers and nuclear medicine departments, the manual quality control procedures and labelling of radiopharmaceuticals with 99mTc isotope manifest the greatest contribution to the recorded Hp(0.07). CONCLUSIONS: The simplicity of obtaining the 99mTc isotope as well as the complex, but fully automated production process of the 18F-FDG radiopharmaceutical optimize the radiation protection of workers, excluding manual procedures labelling with 99mTc or quality control of 18F-FDG. Med Pr 2018;69(3):317327.
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Fluordesoxiglucose F18/química , Exposição Ocupacional/análise , Exposição à Radiação/análise , Proteção Radiológica/métodos , Compostos Radiofarmacêuticos/química , Diagnóstico por Imagem/efeitos adversos , Humanos , Medicina Nuclear , Exposição Ocupacional/prevenção & controle , Polônia , Doses de Radiação , Exposição à Radiação/prevenção & controleRESUMO
Decreasing the individual dose limit for the eye lens means verifying the need for routine monitoring of the eye lens of workers exposed to ionizing radiation, including those employed in facilities producing radiopharmaceuticals based on short-lived isotopes. This work analyses the exposure of the eye lenses of employees of centres that produce the isotopes for positron emission tomography, in particular fluorine-18. It takes into account the employment structure and work system of the discussed centres, including in terms of changing the dose limit value for the eye lens. The work complements the Part I, which examines the hand exposure of workers in the radiopharmaceutical production centres. Measurements were carried out by using high-sensitivity thermoluminescence detectors (LiF: Mg, Cu, P - MCP-N). The measurements covered 17 employees. Our results show that the highest values of personal dose equivalent Hp(3) were recorded for the 18F-FDG quality control personnel and nurses who injected the radiopharmaceutical to the patients. In the group of nurses, the maximum daily Hp(3) reaches a value close to 200 µSv. For staff who performed the quality control of 18F-FDG, the maximum daily dose of Hp(3) exceeds 200 µSv. Estimated annual exposure of eye lenses of workers in these two occupational groups may exceed the new dose limit (20 mSv/year). Results of this study indicate the need for optimization in the procedures related to quality control of radiopharmaceuticals and injection the 18F-FDG to the patients.
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BACKGROUND: The use of X-ray in dental procedures causes exposure of the patient to ionizing radiation. This exposure depends primarily on the parameters used in tooth examination. The aim of the study was to determine the patients exposure and to assess the technical condition of X-ray tubes. MATERIAL AND METHODS: Seventeen hundred dental offices were covered by the questionnaire survey and 740 questionnaires were sent back. Direct measurements were performed in 100 units by using the thermoluminescent detectors and X-ray films. RESULTS: The results showed that the most commonly used exposure time is 0.22±0.16 s. The average entrance dose for the parameters used most commonly by dentists is 1.7±1.4 mGy. The average efficiency of X-ray tube estimated on the basis of exposures is 46.5±23.7 µGy/mAs. CONCLUSIONS: The study results indicate that the vast majority of X-ray tubes meet the requirements specified in the binding regulations. Med Pr 2017;67(4):491-496.
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Doses de Radiação , Radiografia Dentária/estatística & dados numéricos , Raios X , Humanos , Segurança do Paciente/estatística & dados numéricos , Exposição à Radiação , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Thermoluminescent detectors, type MTS-6, containing isotope 6Li (lithium) are sensitive in the range of thermal neutron energy; the 239Pu-Be (plutonium-and-beryllium) source emits neutrons in the energy range from 1 to 11 MeV. These seemingly contradictory elements may be combined by using the paraffin moderator, a determined density of thermal neutrons in the paraffin block and a conversion coefficient neutron flux to kerma, not forgetting the simultaneous registration of the photon radiation inseparable from the companion neutron radiation. The main aim of this work is to present the idea of calibration of thermoluminescent detectors that consist of a 6Li isotope, by using 239Pu-Be neutron radiation source. MATERIAL AND METHODS: In this work, MTS-6 and MTS-7 thermoluminescent detectors and a plutonium-and-beryllium (239Pu-Be) neutron source were used. Paraffin wax fills the block, acting as a moderator. The calibration idea was based on the determination of dose equivalent rate based on the average kerma rate calculated taking into account the empirically determined function describing the density of thermal neutron flux in the paraffin block and a conversion coefficient neutron flux to kerma. RESULTS: The calculated value of the thermal neutron flux density was 1817.5 neutrons/cm2/s and the average value of kerma rate determined on this basis amounted to 244 µGy/h, and the dose equivalent rate 610 µSv/h. The calculated value allowed for the assessment of the length of time of exposure of the detectors directly in the paraffin block. CONCLUSIONS: The calibration coefficient for the used batch of detectors is (6.80±0.42)×10-7 Sv/impulse. Med Pr 2017;68(6):705-710.
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Berílio , Plutônio , Doses de Radiação , Monitoramento de Radiação/métodos , Calibragem , Monitoramento Ambiental/métodos , Humanos , Monitoramento de Radiação/instrumentaçãoRESUMO
18F-FDG is the most popular radiopharmaceutical used, among others, in oncological diagnostics by PET technique. The production of 18F-FDG is a multistep process that begins by obtaining the radioisotope 18F, and subsequently labelling the radiopharmaceutical, as well as quality control of the resulting compound. In each of these stages, the employee has contact with ionizing radiation. The production of 18F requires the use of a cyclotron device. Currently in Poland, there are 9 centres equipped with a cyclotron for the production of positron-emitting radioisotopes. The monitoring of the occupational exposure to ionizing radiation in these centres is performed by measuring the effective and equivalent dose. Neither of these forms fully reflects the exposure of the worker, which is largely associated with handling procedures. The 18F radiopharmaceutical preparation process runs automatically, which partially reduces the level of staff exposure, but the quality control step of the pharmaceutical requires handling procedures with a vial containing an activity of a radiopharmaceutical ranging from 4 GBq to 10 GBq. In the work presented, measurements were performed of hand exposure, in units the equivalent dose (H p (0.07)), of the staff who are involved in the procedures of 18F-FDG production in one of the national production centres. The high-sensitivity thermoluminescent detectors (MCP) were used to measure the doses. The measurements were performed for three groups of workers: operators of the cyclotron, those who produce the 18F-FDG, and quality control staff. Detectors were placed on the fingertips of the left and right hand, as well as in a standard ring dosemeter location. The results indicate that the largest exposure happens among the group of workers involved in the radiopharmaceutical's quality control. The doses recorded by the MCP detectors placed on the fingertips during one working day reach a value up to 2 mSv, which may result in exceeding the annual dose limit (500 mSv).
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Fluordesoxiglucose F18/química , Mãos/efeitos da radiação , Exposição Ocupacional/análise , Exposição à Radiação/análise , Proteção Radiológica/métodos , Compostos Radiofarmacêuticos/química , Humanos , Polônia , Dosimetria TermoluminescenteRESUMO
Positron emission tomography (PET) is now one of the most important methods in the diagnosis of cancer diseases. Due to the rapid growth of PET/CT centres in Poland in less than a decade, radiation protection and, consequently, the assessment of worker exposure to ionising radiation, emitted mainly by the isotope (18)F, have become essential issues. The main aim of the study was to analyse the doses received by workers employed in the Medical Diagnostic Centre. The analysis comprises a physicist, three nurses, three physicians, three technicians, as well as two administrative staff employees. High-sensitivity thermoluminescent detectors (TLDs) were used to measure the doses for medical staff. The personnel was classified into categories, among them employees having direct contact with the 'source of radiation'-(18)FDG. The TLDs were placed on the fingertips of both hands and they were also attached at the level of eye lenses, thyroid and gonads depending on the assigned category. The highest dose of radiation was observed during the administration of the (18)FDG to the patients. In the case of the physicist, the highest dose was recorded during preparation of the radiopharmaceutical-(18)FDG. The body parts most exposed to ionizing radiation are the fingertips of the thumb, index and middle finger.
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Fluordesoxiglucose F18/análise , Pessoal de Saúde/estatística & dados numéricos , Exposição Ocupacional/estatística & dados numéricos , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Doses de Radiação , Dosimetria Termoluminescente/estatística & dados numéricos , Humanos , Imagem Multimodal/estatística & dados numéricos , Polônia/epidemiologia , Compostos Radiofarmacêuticos/análise , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Dosimetria Termoluminescente/instrumentação , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Contagem Corporal Total/estatística & dados numéricosRESUMO
BACKGROUND: There are about 200 underground tourist routes in Poland. There are caves, mines or underground structures. This paper presents the results of the research intended to identify the extent of the occurrence of radon concentrations in underground areas of tourist routes. MATERIAL AND METHODS: We conducted the measurement of periodic concentrations of radon (1-2 months) in the summer using type Tastrak trace detectors. We determined the average concentrations of radon in air in 66 underground tourist routes in Poland. RESULTS: The research results comprise 259 determinations of average radon concentrations in 66 routes. The arithmetic average of the results was 1610 Bqm-3, and the maximum measured concentration was over 20,000 Bqm-3. The minimum concentration was 100 Bqm-3 (threshold method) considering the arithmetic average of the measurements. It was found that in 67% of the routes, the average concentration of radon has exceeded 300 Bqm-3 and in 22 underground routes it exceeded 1000 Bqm-3. CONCLUSIONS: Radon which occurs in many Polish underground tourist routes may be an organizational, legal and health problem. It is necessary to develop a program of measures to reduce radon concentrations in underground routes, especially routes located in the former mines.
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Poluentes Radioativos do Ar/análise , Cavernas , Monitoramento de Radiação/métodos , Radônio/análise , Viagem , Humanos , Polônia , Proteção Radiológica/métodos , Fatores de RiscoRESUMO
The mature larva and pupa of Otiorhynchus smreczynskii are described and illustrated with complete chaetotaxy for the first time. Five larval instars and the factors for larval growth are determined, and the larval development of this species is comprehensively described. In order to confirm species affiliation, selected larvae were subjected to genetic analysis (mtCOI). Host plants and unique feeding signs of some Entiminae species are presented, and all available data on development are documented and interpreted. Additionally, the morphometry of 78 specimens (48 of O. smreczynskii and 30 of O. rotundus) was examined in order to verify the usefulness of morphological features in distinguishing both species. The female genitalia of both species are illustrated, described and compared with each other for the first time. Finally, the updated distribution of O. smreczynskii is given, and a possible origin of O. smreczynskii and O. rotundus is proposed.
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OBJECTIVES: While working with cyclotrons used for the production of radiopharmaceuticals, workers can experience significant exposure to the adverse effects of ionizing radiation. The aim of this paper was to determine the typical level of such exposure received by such personnel while servicing cyclotrons. MATERIAL AND METHODS: Exposure was assessed using TLD detectors placed in an anthropomorphic phantom, as well as dose meter to determine whole body and eye lens exposure. The phantom was placed in locations receiving the greatest exposure to ionizing radiation during service activities. The time spent by employees during servicing was assessed based on routine visits by service technicians. The obtained results were compared with readings of detectors worn by employees during service activities. RESULTS: The highest equivalent doses in the thoracic area were found to be received by the lungs (211.16 µSv/year). In the head and neck area, the highest dose was measured in the eye lens (3410 µSv/year). The effective dose for the whole body was found to be 1154.4 µSv/year, based on the phantom, and 149 µSv per service visit (1192 µSv/year), based on the dose meters carried by the workers. CONCLUSIONS: Service workers are exposed to significant doses of ionizing radiation, representing a clear radiological protection issue. To reduce exposure to eye lenses, it is recommended to use protective goggles when working with highly-radioactive elements. Int J Occup Med Environ Health. 2022;35(6):753-60.
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Exposição Ocupacional , Exposição à Radiação , Humanos , Compostos Radiofarmacêuticos , Exposição Ocupacional/efeitos adversos , Ciclotrons , Radiação Ionizante , Tomografia por Emissão de Pósitrons , Doses de RadiaçãoRESUMO
In Europe, honey bees and bumble bees are among the most important pollinators, and there is a growing interest in understanding the effects of floral resource availability on their survival. Yet, to date, data on nectar and pollen supplies available to bees in agricultural landscapes are still scarce. In this paper, we quantify species-, habitat- and landscape-scale pollen production in the Lublin Upland, SE Poland. The production per unit area was highest (mean = 2.2-2.6 g/m2) in non-forest woody vegetation, field margins and fallows, whilst significantly lower pollen amounts were shown to be available in road verges and railway embankments (mean = 1.3-1.6 g/m2). At landscape scale, natural and semi-natural areas (forests and meadows/pastures) offered ca. 44% of the total pollen resources during the year. Relatively high amounts of pollen (ca. 35% of the year-round total pollen resources) were from winter rape, but this resource was short-term. Man-made, non-cropped habitats added only ca. 18% of the total pollen mass offered for pollinators during flowering season. However, they provided 66-99% of pollen resources available from July to October. There exists an imbalance in the availability of pollen resources throughout the year. Hence, a diversity of natural, semi-natural and man-made, non-cropped areas is required to support the seasonal continuity of pollen resources for pollinators in an agricultural landscape. Efforts should be made to secure habitat heterogeneity to enhance the flower diversity and continual pollen availability for pollinators.
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Pólen , Polinização , Animais , Abelhas , Produtos Agrícolas , Ecossistema , Humanos , Néctar de Plantas , Plantas DaninhasRESUMO
The scarcity of floral resources and their seasonal discontinuity are considered as major factors for pollinator decline in intensified agricultural landscapes worldwide. The consequences are detrimental for the stability of the environment and ecosystems. Here, we quantified the production of nectar sugars in plant species occurring in man-made, non-cropped areas (non-forest woody vegetation, road verges, railway embankments, field margins, fallow areas) of an agricultural landscape in SE Poland. We also assessed changes in the availability of sugar resources both in space (habitat and landscape scales) and in time (throughout the flowering season), and checked to what extent the sugar demands of honeybees and bumblebees are met at the landscape scale. At landscape-level, 37.6% of the available sugar resources are produced in man-made, non-cropped habitats, while 32.6% and 15.0% of sugars derive from winter rape crops and forest vegetation, respectively. Nectar sugar supplies vary greatly between man-made, non-cropped habitat types/sub-types. These areas are characterized by a high richness of nectar-producing species. However, a predominant role in total sugar resources is ascribable to a few species. Strong fluctuations in nectar resources are recorded throughout the flowering season. March and June are periods with food shortages. Abundant nectar sugars are generally found in April-May, mainly due to the mass flowering of nectar-yielding species in the forests, meadows/pastures and orchards/rapeseed crops. Heterogeneity of man-made, non-cropped habitats is essential to support the supply of July-October nectar sugars for honeybees and bumblebees. Reduced flowering in man-made non-cropped habitats can generate serious food deficiencies, as from summer towards the end of the flowering season >90% of sugars are provided by the flora of these areas. Therefore, highly nectar-yielding plant species that flower during periods of expected food shortages should be a priority for conservation and restoration programs.
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Ecossistema , Néctar de Plantas , Animais , Abelhas , Humanos , Polônia , Polinização , AçúcaresRESUMO
AIMS: The issue of exposure of eye lenses of employees exposed to ionizing radiation is an interesting topic not only from the point of view of deterministic effects related to the occurrence of cataracts, but also dosimetric aspects, in particular the calibration of detectors in units enabling the assessment of eye lens exposure or personal dose equivalent Hp(3). The paper presents the idea of calibrating thermoluminescent detectors designed for the Hp(3) values measurement of gamma radiation, which the source is the process of annihilation of positrons emitted by the deoxyglucose marker - 18F radionuclide. METHODS: The method was based on the value of air kerma Ka to Hp(3) conversion coefficients (Hp(3,0°)/Ka) developed as part of the ORAMED project. High-sensitivity thermoluminescent detectors (MCP-N) produced in Poland were used in the measurements. During the exposure of the detectors, a 137Cs gamma radiation source (irradiator 137Cs/60Co) and a 20cm diameter cylinder filled with water were used. RESULTS & CONCLUSIONS: The value of conversion coefficient Hp(3,0°)/Ka for energy 511 keV is 1.31Sv/Gy and the calibration factor is (3.46±0.03)·10-4 mSv/N (N - number of counts). Verification of the value of the obtained coefficient carried out using a cylinder with a diameter of 20cm showed a difference of less than 2% in relation to the value obtained by the method described in this paper.
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Dosimetria Termoluminescente , Calibragem , HumanosRESUMO
BACKGROUND: The method of measuring doses based on the thermoluminescence phenomenon is not an absolute method. For this reason, to obtain correct results, it is necessary to calibrate detectors in the known radiation field. This paper presents a method for calibrating thermoluminescent detectors used in the measurement of personal dose equivalents (Hp(0.07)) obtained by nuclear medicine facility personnel when handling the 99mTc radionuclide. MATERIAL AND METHODS: The authors used self-developed high-sensitivity thermoluminescent detectors and a HF320C X-ray unit, as well as a rod phantom. Dosimeters were calibrated in accordance with the ISO 4037-3 standard. During the measurements a vial containing a 99mTc radionuclide with well-known activity was also used. The energy characteristics were supplemented by using a 137Cs source (irradiator 60Co/137Cs). RESULTS: The value of the calibration coefficient for 118 keV energy energy was (1.90±0.02)×10-5 mSv/imp. Taking into account the correction factor specified for of 140 keV energy at 0.962, the value of the calibration coefficient for 140 keV energy was determined as (1.83±0.02)×10-5 mSv/imp. CONCLUSIONS: Verification of the calibration coefficient determined for 140 keV energy carried out with a vial containing a 99mTc radionuclide confirmed the correctness of the procedure. Med Pr. 2019;70(6):669-73.
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Monitoramento Biológico/instrumentação , Monitoramento Biológico/métodos , Calibragem/normas , Raios gama/efeitos adversos , Luminescência , Medicina Nuclear/normas , Dosimetria Termoluminescente/normas , Absorção de Radiação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/normasRESUMO
The production of 18F-FDG is a multi-stage process, which includes not only obtaining the marker and labelling the radiopharmaceutical but also carrying out the quality control of the obtained compound. The staff can be exposed to ionizing radiation at any stage of production. This article presents the results of hands exposure of staff members employed in a facility, where 18F-FDG is produced and injected into patients. High-sensitivity thermoluminescent detectors (MCP-N) were used for measurements. The measurements were conducted with regard to the occupational structure the employees and the performed procedures. The obtained results showed that the highest risk of radiation exposure for personnel was associated with the quality control of the radiopharmaceutical. The daily doses registered by MCP-N detectors on fingertips reached 4.5 mSv, which may result in exceeding the annual radiation limit of 500 mSv.
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Fluordesoxiglucose F18/síntese química , Mãos/efeitos da radiação , Medicina Nuclear , Exposição Ocupacional/análise , Exposição à Radiação/análise , Monitoramento de Radiação/métodos , Compostos Radiofarmacêuticos/síntese química , Humanos , Doses de Radiação , Proteção Radiológica , Radiação IonizanteRESUMO
The production of the 18F isotope-the marker of deoxyglucose (18F-FDG)-the radiopharmaceutical most commonly used in the oncological diagnostic technique of positron emission tomography, requires a cyclotron device. At present, there are nine facilities working in Poland that are equipped with cyclotrons used for producing the short-lived isotopes. The aim of the paper is to determine the hand exposure of workers employed in the two 18F-FDG production centres taking in to account the production procedures and work system in those facilities. Measurements, which included all professional workers exposed to ionizing radiation that were employed in two facilities, were performed by using high-sensitivity thermoluminescent detectors during the routine activities of the personnel. The work system used at the production centre has an impact on the level of the recorded doses. Among the production procedures performed by the staff, the highest ionizing radiation doses have been received by the staff during the 18F-FDG quality control. The maximum estimated annual Hp(0.07) for chemists from the quality control department can exceed the annual skin limit dose (500 mSv). The source of lowest doses on the hands are the cyclotron operating procedure and the 18F-FDG production, provided that these procedures can't be combined with other production procedures.