Evaluation of internal doses to workers and monitoring of 131I concentration in air in nuclear medicine workplaces / 中华放射医学与防护杂志

Objective:To asscentain the 131I activity concentration in 131I treatment workplaces and to explore the method of estimating the internal dose to workers by air sampling and to analyze its influencing factors. Methods:Air sampling method was used to collect aerosols containing radioactivity in 10 randomly selected workplaces in Zhengzhou where 131I therapy was performed. Aactivity concentration of 131I in treatment workplace was measured for gamma emitters by gamma-ray spectrometry. The internal dose due to 131I inhalation was estimated based on measurement result and field investigation result. Results:The activity concentration of 131I in air samples from 19 subpacking rooms ranged from 0.087 to 570 Bq/m 3, with an average of (51.04 ± 128.58) Bq/m 3. Those from 11 wards ranged from 0.162 to 54.6 Bq/m 3, with an average of (7.97 ± 15.89) Bq/m 3. In terms of the work hours recommended by the national standard GBZ 129-2016 Specifications for individual monitoring of occupational internal exposure, the estimated annual effective dose to radiation workers due to the inhalation of 131I ranges from 0.002 to 10 mSv, with an average of (0.61 ± 1.80) mSv, below the dose limit specified in the national standards. Conclusions:The samples with high 131I activity concentration in nuclear medicine workplaces of 10 medical institutions selected in Zhengzhou are mostly distributed in tertiary class hospitals operating large amount of radionuclide with large numbers of thyroid cancer patients adimitted. The result ing internal dose to radiation workers cannot be ignored. Estimating the internal dose based on the measurement result of air samples has a large uncertainty.However, air sampling method can promptly detect radioactive contamination in case of abnormal events or accidents, providing early warning for workers to carry out dose measurement from external exposure and internal exposure assessment.

Chloro-nitrobenzene compounds air sampling tube preparation and determination method / 中国职业医学

@#Objective - - To prepare the GDH 5 air sampling tube for simultaneous collection of eight kinds of chloro nitrobenzene （ ） ， compounds CNBs in the air of workplace and establish a matching determination method using gas chromatography. Methods - - ， Eight kinds of CNBs in vapor and aerosol state were collected by self developed GDH 5 air sampling tube desorbed ， ， ， by toluene separated by polysiloxane gas chromatography column detected by microcell electron capture detector and Results - （ - quantified by external standard method. It was determined that the air sampling tube was assembled by XAD 2 ion ） - ， exchange resin and glass fiber filter membrane. The linear range of CNBs was 0.80 240.00 mg/L and the linear correlation - - coefficients were greater than 0.999 9. The detection limit was 7.87 13.03 μg/L. The minimum detectable concentration was 0.60 3， - 3（ ） 1.33 μg/m and the minimum quantitative concentration was 2.00 4.22 μg/m sample 45.00 L . The average desorption - - （RSD） - ， - RSD efficiency was 101.2% 110.0%. The within run relative standard deviation was 0.8% 4.1% and the between run - Conclusion - was 0.3% 5.8%. The samples could be stored for more than 30 days at room temperature. GDH 5 air sampling tube and its associated determination method can be used for the collection and determination of eight kinds of CNBs in workplace air.

Preparation of air sampling tube for chlorobenzene compounds and establishment of its matching detecting method / 中国职业医学

OBJECTIVE: To prepare and develop a GDH-2 air sampling tube for detecting 12 kinds of chlorobenzenes(CBs) in workplace air and to establish a matching detecting method. METHODS: The self-developed GDH-2 air sampling tube was filled with ion exchange resin and activated carbon, and the mass ratio was 10 ∶1. The GDH-2 air sampling tube was used to collect 12 kinds of CBs with coexistence of gaseous and aerosol in the air. After elution with toluene, they were separated on a chromatographic column and determined by microcell electron capture detector. RESULTS: The quantitative detecting range of the method was 0.51×10~(-3)-6 000.00 mg/L, with the correlation coefficients greater than 0.999 4. The minimum detection concentration was 0.02-61.99 μg/m~3, and the minimum quantitative concentration was 0.05-206.62 μg/m~3. The average desorption efficiency was 90.8%-104.0%. The within-run relative standard deviation(RSD) was 1.0%-5.7%, and the between-run RSD was 3.0%-7.3%. The samples can be stored at room temperature for at least 26 days. CONCLUSION: The self-developed GDH-2 air sampling tube and its matching measuring method can be used for the collection and determination of the 12 kinds of CBs in the air of workplace.

Monitoring results and analysis of 131I in the air of workplace treated with iodine / 中华放射医学与防护杂志

Objective:To understand the activity concentration of 131I aerosol in the air of the iodine treatment workplace and estimate the internal dose of 131I inhaled by medical staff in nuclear medicine. Methods:Using CF-1001BRL portable large capacity air sampler, the 131I aerosol in the iodine treatment workplace of nuclear medicine department of 6 hospitals in Shandong province was collected by iodine box, and the HPGe-γ energy spectrometer was used to measure the samples. The 131I activity concentration in iodine treatment workplace at 6 hospitals was obtained, and the internal dose to medical staff was estimated. Results:The 131I activity concentration in the air in iodine treatment workplaces at 6 hospitals ranged from 3.64 to 2.94×10 3 Bq/m 3. The 131I activity concentration in the controlled area (ward, patient passageway, subpacking room, operation administration room) was significantly higher than that in the supervised area. The highest 131I activity concentration, 2.62×10 2 Bq/m 3, in the supervised area was found in the medical care passageway. The estimated effective dose to nuclear medicine workers was 0.07-5.68 mSv, not exceeding the national limit. Conclusions:The phenomenon of 131I aerosol contamination still exists in the iodine treatment workplaces of nuclear medicine departments in hospitals, so it is necessary to carry out internal radiation monitoring for nuclear medicine departments all around the country, and explore more reasonable protection standards and methods.

Simultaneous detection of 6 isomers of dimethylaniline in workplace air by gas chromatography / 中国职业医学

OBJECTIVE: To establish a method for simultaneous detection of 6 isomers of dimethylaniline(DMA) in workplace air by gas chromatography(GC). METHODS: The vapor and aerosol DMA in workplace air were collected by GDH-1 air sampling tube, and desorbed and eluted with absolute ethanol, then separated by a special capillary column for amines analysis, and finally detected by GC-flame ionization detector. RESULTS: The quantitative detection range of 6 isomers of DMA was 0.26-226.66 mg/L, with all the correlation coefficients greater than 0.999 00. The minimum detectable concentration was 0.01-0.02 mg/m~3, and the minimum quantification concentration was 0.04-0.05 mg/m~(3 )(15.00 L sample, 2.00 mL sample solution). The average desorption and elution efficiency was 92.48%-104.60%. The within-run relative standard deviations(RSD) was 0.31%-4.51%, and the between-run RSD was 1.23%-6.03%. The samples can be sealed and stored for more than 19 days at room temperature. CONCLUSION: The method is suitable for simultaneous detection of 6 isomers of DMA in workplace air.

Isolation of fungi in indoor air environment of selected air-conditioned and non-airconditioned wards in a public tertiary hospital in Metro Manila, Philippines

Background and Objectives@#The hospital as health care facility has also become a source of infection that provides a place for different microbiological agents such as fungi. Exposure to these organisms is specifically detrimental to highly immunocompromised in-house patients. This study aimed to 1) detect the presence of fungi in a public tertiary hospital in Metro Manila; 2) determine the dominating fungal organism; and 3) describe the environmental conditions and physical factors affecting the proliferation of fungal organisms. @*Methodology@#Eight sampling sites were selected for this study. The hospital main lobby was the comparison site for the three non-air-conditioned surgery wards (NACWs) while the fourth level nurse station is the comparison site for the air-conditioned wards (ACWs). Meteorologic conditions such as environmental temperature and relative humidity were also determined. Andersen air sampler was utilized to conduct the environmental indoor air sampling. A total of 98 malt extract agar supplemented with chloramphenicol (0.01%) plates were utilized for the duplicate sampling in eight sites. After three to five days of incubation at 37° C, the isolated fungal organisms were culturally and morphologically characterized. @*Results@#Seven fungal organisms were isolated from the indoor air sampling conducted namely: Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Curvularia sp., Penicillium sp., Alternaria sp. and Rhizopus sp.). The most dominant fungal species among the NACWs was A. niger. On the other hand, A. fumigatus was the most observed isolate among the ACWs. The air-conditioned wards showed a higher number of fungal isolates. In particular, A. fumigatus and A. flavus colonies in the ACWs were evidently higher than in the NACWs. @*Conclusion@#The ubiquitous nature of the Aspergillus species and slow settling rate due to small spore size make it the most dominant fungal organism retrieved in the air sampling conducted. No strict numerical guidelines were available for the spore counts of Aspergillus species to assess contamination rate. However, according to the Health Protection Surveillance Centre, 2018, the values of CFU/m³ of most of the isolates not only by Aspergillus species showed non-compliance with the threshold level documented.

Microbiological Assessment of Selected Laboratories at a Local University in Malaysia / Jurnal Sains Kesihatan Malaysia

@#Microbiological contaminations in the laboratories create not only diagnostic issues but also pose a major health risk to lab users. This study was conducted to determine the airborne microbial contamination in seven selected laboratories (KA, KP, PB, NA, BP, CR and MB) at a local public university in Malaysia and to assess the level of contamination on the contact surfaces of the studied laboratories. Two types of sampling methods were used in this study; passive air sampling and contact surface swab sampling. The total microbial counts were determined using Tryptone Soya agar (bacterial count) and Potato Dextrose agar (fungal count). Results showed that NA laboratory had the highest level of total microbial contamination (20.33 ± 3.35 CFU/cm3 ). Most laboratories had significantly higher (p < 0.05) air fungal contamination level compared to bacterial contaminations except for PB and NA laboratories. Significant differences were observed for airborne bacterial contamination readings between sampling time (during working hours vs after hours) for all laboratories except for BP and CR. Overall, bacterial contamination was the highest for incubator door handles’ samples from MB laboratory with an average reading of 93.00 ± 1.43 CFU/cm2 whereas the highest fungal contamination level was obtained from door knobs and work benches, both from CR laboratory with an average reading of 73.33 ± 6.67 CFU/cm2 and 73.33 ± 0.58 CFU/cm2 respectively. Findings from this study could assist in monitoring the efficacy of the existing laboratory management systems namely on the good laboratory practices including aseptic techniques, care for laboratory hygiene and cross-contamination control practices by the laboratory users to ensure that the microbiological contaminations in the laboratories are minimized.

Exposure to airborne asbestos in Jamaican hospitals / Exposición al asbesto suspendido en el aire en hospitales de Jamaica

OBJECTIVE: Asbestos is an established human carcinogen and has been identified at 16 of 26 Jamaican hospitals surveyed. We sought to determine if hospital employees are exposed and if current asbestos exposure in Jamaican hospitals differed by job category. METHOD: At two of the largest hospitals with more than 10 permanent maintenance workers and where over 67% of bulk samples analysed contained asbestos, three groups of employees selected by stratified random sampling participated in a personal air sampling study for asbestos. One hundred and thirty-two personal air samples and 32 area samples were collected and analysed for asbestos fibres utilizing phase contrast microscopy (PCM) and transmission electron microscopy (TEM). RESULTS: Twenty-four (14.6%) air samples had fibre counts above the limit of detection (LOD) for the analytical method (PCM), ranging from 0.002f/cc to 0.013 f/cc. The fibres met the dimensional characteristics ofasbestos fibres. There was no difference in the median fibre concentration to which the groups of employees were exposed. Further testing of samples which had fibre counts above the LOD using TEM confirmed that the fibres were not asbestos. CONCLUSION: Despite not finding asbestos fibres in the air samples, most of the asbestos containing building material (ACBM) found in the hospitals was friable and in a poor condition indicative of fibre release. We recommend an ongoing monitoring programme for airborne asbestos fibres in hospitals until an abatement programme can be undertaken by the regulatory agencies in the country.

OBJETIVO: El asbesto, también llamado amianto, es un carcinógeno humano conocido, y ha sido identificado en 16 de 26 hospitales jamaicanos investigados. El presente trabajo tuvo por objeto determinar si los empleados del hospital están expuestos al asbesto, y si la exposición actual de asbesto en hospitales jamaicanos difiere según la categoría del trabajo. MÉTODO: En dos de los hospitales más grandes con más de 10 obreros de mantenimiento permanentes y dónde más del 67% de las muestras a granel analizadas contenían asbesto, tres grupos de empleados seleccionados por muestreo aleatorio estratificado participaron en una investigación de muestreo de aire personal en busca de asbesto. Ciento treinta y dos muestras de aire personal y 32 muestras de área fueron recogidas y analizadas en busca de fibras de asbesto, utilizando microscopía de contraste de fases (MCF) y microscopía electrónica de transmisión (MET). RESULTADOS: Veinticuatro (14.6%) muestras de aire tuvieron un conteo de fibras por encima del límite de detección (LDD) para el método analítico (MCF), que fluctuaba de 0.002 f/cc a 0.013 f/cc. Las fibras correspondían a las características dimensionales de las fibras de asbesto. No hubo diferencias en la concentración mediana de las fibras a la que los grupos de empleados estaban expuestos. Pruebas posteriores con las muestras que arrojaron conteos de fibras por encima del LDD usando la MET, confirmaron que las fibras no eran de asbesto. CONCLUSIÓN: A pesar de que no se encontraron fibras de asbesto en las muestras de aire, la mayor parte de los materiales de construcción que contienen asbesto (ACBM) hallados en los hospitales eran friables y estaban en mal estado, dando ya señales de desprendimiento de fibras. Se recomienda un programa de monitoreo de fibras de asbesto suspendidas en el aire en los hospitales hasta que pueda emprenderse un programa de eliminación de las mismas por parte de las agencias reguladoras del país.

Estimation of internal dose with aerosol clust inhaled by non-uranium miners / 中华放射医学与防护杂志

Objective To establish a method for estimating internal dose from aerosol inhalation in non-uranium miners.Methods Aerosol samples in a tunnel in Dongchuan Copper Mine in Yunnan Province were collected by portable high flux air sampler.Radionuclides collected at the sampler filters were analyzed by the gamma spectrometry.Annual committed effective dose due to inhalation of the aerosol dust was estimated using the formula provided by ASTM.Results Radionuclides collected in two aerosol samples were anlayzed,the annual committed effective doses due to inhalation of 1 μm and 5 μm aerosol were estimated.Conclusions The method of using high flux air sampling and gamma spectrometry is explored to estimate the dose from aerosol inhalation.

Advance in Analytical Methods for Phthalate Esters in Air / 环境与健康杂志

Phthalate esters belong to the group of environmental hormones,which are ubiquitous environmental pollutants and they can damage the human health through breathing to get into the body.The recent researches on the analysis of phthalate esters in the air such as sampling,pretreatment and determination were reviewed and some related issues were discussed in the paper.It would be reference for the further study of phthalate esters.

Filamentous Fungi Isolated from Hospital Air and from Clinical Specimens / 병원감염관리

BACKGROUND: As the population of immunocompromised patients continues to grow, the incidence of infections caused by opportunistic filamentous fungi will continue to increase. Inhalation of fungal spores which are found in the environmental air precedes infection with molds. We investigated the relative frequency of various molds recovered from hospital air as compared to isolates from clinical specimens. METHODS: Air samples were taken from 83 sites in Chonnam University Hospital during December 1997. Air sampler (Biotest, Germany) with Rose Bengal agar strip (Biotest, Germany) was calibrated to take 40 liters of air. The strips were incubated at 37degrees C for 2-14 days. The results of air cultures were compared with those from the clinical specimens during a year (1997). RESULTS: Of 83 air samples cultured, 61 (73.5%) were positive for molds: 43 (51.8%) samples with 1-2 CFU, 15 (18.1 %) samples with 3-5 CFU, and 3 (3.6%) samples with > 5 CFU. A total of 184 molds were isolated and the most frequently recovered molds were Cladosporium (26.0%), followed by Penicillium (25.5%), Aspergillus (18.5%) and Alternaria (9.8%). The most frequently isolated molds from clinical specimens were Aspergillus (62.8%) and Fusarium (20.2%). For Aspergillus species, A. flavus (28,8%) and A. fumigates (25.4%) were predominant among the clinical isolates, whereas A sydowii (44.1%) and A. niger (38.2%) were common in the hospital air. CONCLUSION: This result shows that Cladosporium and Penicillium are the predominant molds in the hospital air and the relative frequency of molds recovered from hospital air is quite different from those of clinical isolates.