1.Skin irritant potency of occupationally hazardous chemicals usingkeatinocyte culture model and blood flow measurement.
Hee Chul EUN ; Duk Kyu CHUN ; Seon Hoon KIM
Korean Journal of Occupational and Environmental Medicine 1991;3(2):145-152
No abstract available.
Hazardous Substances*
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Occupations*
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Skin*
2.Isolation of Extended Spectrum ß-lactamase (ESBL) Producing Bacteria from Urban Surface Waters in Malaysia
Malaysian Journal of Medical Sciences 2013;20(3):14-22
Background: This was a preliminary study to test for the presence of multiple antibiotic-resistant extended spectrum β-lactamase (ESBL) producing bacteria in Malaysian urban surface waters. Although the literature review revealed several published papers on clinical ESBL isolates in Malaysia, none were found on ESBL isolates obtained from local surface waters.
Methods: Isolated bacterial species were tested for resistance to cefotaxime, amoxicillin/clavulanate and aztreonam, and susceptibility to imipenem and meropenem using antibiotic susceptibility testing (AST) by disc diffusion. This served as a screening step to detect bacteria that could be potential ESBL species. 16S ribose ribonucleic acid (rRNA) polymerase chain reaction (PCR) testing with two clusters of bla (β-lactamase) gene primers was used to test for the bla genes CTX-M (Groups 1, 2, 9), OXA-1, SHV and TEM.
Results: A total of 19 isolates were found, possessing at least one of the bla genes tested for. There was a relatively high occurrence of CTX-M genes (84.2%) among these, followed by TEM genes (47.4%). The isolates were identified as Enterobacteriaceae (89.5%), predominantly Escherichia coli and Klebsiella pneumoniae.
Conclusion: There appears to be a high occurrence of ESBL-bacteria in local surface waters, among these being opportunistic pathogens. The persistence and spread of these species in the environment poses a threat to exposed human populations.
Hazardous Substances
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Bacteria
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Water
3.Chlorpyrifos Blood Level and Exposure Symptoms among Paddy Farmers in Sabak Bernam, Malaysia
Rozita Hod ; Azimatun Noor Aizuddin ; Shamsul Azhar Shah ; Mohd Rohaizat Hassan ; Nazarudin Safian ; Mohd Hasni Jaafar
International Journal of Public Health Research 2011;1(1):1-6
The extensive and intensive use of pesticides in agricultural practices has exposed farmers to various hazards resulting in varying degrees of health outcomes. We conducted a cross-sectional study among paddy farmers in Sabak Bernam district, Malaysia. The objective of this study was to gather baseline information on chlorpyrifos blood level and its relationship with pesticides exposure symptoms. We detected chlorpyrifos in farmers’ blood in 7 percent of the respondents, with mean 7.29 nanogram per millilitre blood (sd 5.84 nanogram per millilitre). The percentage of farmers who experienced at least one pesticide exposure symptoms was 75 percent. However, we found no significant association between chlorpyrifos blood level and its exposure symptoms. The farmers had low scores on safe practice of pesticide use even though they have high marks on knowledge and attitude. We found no significant association between the scores on knowledge, attitude and practice on pesticide use and the chlorpyrifos blood level. The presence of pesticide exposure symptoms proved that most of the farmers were exposed to hazardous effects of pesticides. Specific trainings on safe use and handling of pesticides should be given on regular basis to these farmers to ensure they are protected from hazardous effects of pesticides exposure.
Chlorpyrifos
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Pesticides
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Hazardous Substances
6.Analysis of the utilization of existing test data for phase-in substance registration under the Act on the Registration and Evaluation, etc. of Chemical Substances.
Bong In CHOI ; Yeong Don KWAK ; Yu Mi JUNG ; Byung Taek RYU ; Chang Gyun KIM
Environmental Health and Toxicology 2015;30(Suppl):s2015004-
OBJECTIVES: Approximately 2000 phase-in substances are subject to registration according to the Act on the Registration and Evaluation, etc. of Chemical Substances (KREACH), and the expected testing cost is 2.06 trillion Korean won assuming all the test data required for registration are acquired. The extent to which these enormous test costs can be reduced depends on the availability of existing data that can be used to meet the requirements of the K-REACH we examined the current availability of test data that can be used for chemical substance registration. METHODS: We analyzed the possibility of utilizing the existing test data obtained from 16 reference databases for 369 of 518 kinds of phase-in substances subject to registration that were reported in last October 2014. RESULTS: The physical and chemical properties were available for 57.1% of substances, whereas data regarding human hazards and environmental hazards were available at considerably lower rates, 8.5% and 11.8%, respectively. CONCLUSIONS: Physical and chemical properties were available for a fairly high proportion, whereas human hazards and environmental hazards were reported for considerably fewer substances.
Chemical Safety
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Hazardous Substances
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Humans
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Safety Management
7.A Meta-analysis of Epidemiological Studies on the Relationship between Occupational Electromagnetic Field Exposure and the Risk of Adult Leukemia
Hongbing WANG ; Yoshihiro MURAI ; Shigehiro NOMURA ; Michikazu SEKINE ; Shigeru SOKEJIMA ; Hideo SAKAI ; Sadanobu KAGAMIMORI
Environmental Health and Preventive Medicine 2000;5(1):43-46
Since the first paper by Milham et al. suggested that occupational exposure to an electromagnetic field (EMF) could increase the risk of adult leukemia, many epidemiological studies on this problem have been published. In this report the method of meta−analysis was used to summarize the results from these papers quantitatively. The combined relative risk of all leukemia (RR=1.11), as well as acute lymphocytic leukemia (RR=1.38), acute myeloid leukemia (RR=1.07) and chronic lymphocytic leukemia (RR=1.14) increased but not significantly. So far, it is difficult to make a consistent conclusion about the relationship of the occupational exposure to EMF and adult leukemia. Further carefully designed case−control and cohort studies using the more valid means of exposure assessment are required.
Leukemia
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Adult
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Risk
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Electromagnetic Fields
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Analysis of substances
8.Advances of polymer-monomer production by cyanobacterial cell factory.
Meiwen QIAN ; Chunlin TAN ; Jun NI ; Fei TAO ; Ping XU
Chinese Journal of Biotechnology 2021;37(3):1017-1031
Cyanobacteria is one of the promising microbial chassis in synthetic biology, which serves as a typical host for light-driven production. With the gradual depletion of fossil resources and intensification of global warming, the research on cyanobacterial cell factory using CO2 as carbon resource is ushering in a new wave. For a long time, research focus on cyanobacterial cell factory has mainly been the production of energy products, such as liquid fuels and hydrogen. One of the critical bottlenecks occurring in cyanobacterial cell factory is the poor economic performance, which is mainly caused by the inherent inefficiency of cyanobacteria. The problem is particularly prominent for these extremely cost-sensitive energy products. As an indispensable basis for modern industry, polymer monomers belong to the bulk chemicals with high added value. Therefore, increasing attention has been focused on polymer monomers which are superior in overcoming the economic barrier in commercialization of cyanobacterial cell factories. Here, we systematically review the progress on the production of polymer monomers using cyanobacteria, including the strategies for improving production, and the related technologies for the application of this important microbial cell factory. Finally, we summarize several issues in cyanobacterial synthetic biology and proposed future developing trends in this field.
Cyanobacteria
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Macromolecular Substances
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Polymers
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Synthetic Biology
9.Re-analysis of occupational hazards in foundry.
Min ZHANG ; Cheng QI ; Wei-Hong CHEN ; Yang LU ; Xie-Yi DU ; Wen-Jie LI ; Chuan-San MENG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2010;28(4):280-285
OBJECTIVETo analyze systematically the characteristics of occupational hazards in the foundry, and provide precise data for epidemiology studies and control of occupational hazards in the foundry.
METHODSData of airborne dust, chemical occupational hazards and physical occupational agents in environment in the foundry from 1978 to 2008 were dynamically collected. Mean concentration and intensity (geometric mean) of occupational hazards were calculated by job in different years.
RESULTSMain occupational hazards in the foundry were silica, metal fume, noise and heat stress. Silica existed in all of main jobs. The mean concentration of silica before 1986 was an extremely high level of 8.6 mg/m(3), and then remarkably dropped after 1986, with the level of 2.4 mg/m(3) from 1986 to 1989, 2.7 mg/m(3) from 1990 to 2002 and 2.7 mg/m(3) from 2003 to 2008. The trend of silica concentrations by job was consistent with that in general. Silica concentrations among jobs were significantly different, with highest level in melting (4.4 mg/m(3)), followed by cast shakeout and finishing (3.4 mg/m(3)), pouring (3.4 mg/m(3)), sand preparation (2.4 mg/m(3)), moulding (2.1 mg/m(3)) and core-making (1.7 mg/m(3)). Concentration of respirable dust in pouring was highest (2.76 mg/m(3)), followed by cast shakeout and finishing (1.14 mg/m(3)). Mean concentration of asbestos dust in melting was a relative high level of 2.0 mg/m(3). In core-making and sand preparation, there existed emission production of adhesive, with mean concentrations as followed, ammonia (5.84 mg/m(3)), formaldehyde (0.60 mg/m(3)), phenol (1.73 mg/m(3)) and phenol formaldehyde resin (1.3 mg/m(3)) also existed. Benzene and its homologues existed in cast shakeout and finishing, and the level of benzene, toluene, xylene was 0.2 mg/m(3), 0.1 mg/m(3) and 1.3 mg/m(3), respectively. In pouring and melting, there existed chemical occupational hazards, including benzo(a) pyrene, metal fume (lead, cadmium, manganese, nickel, chromium) and gas(hydrogen sulfide, phosphine, sulfur dioxide, carbon monoxide). Mean concentration of benzo(a) pyrene was a low level of 1.80 x 10(-4) microg/m(3). Physical occupational agents in the foundry were noise, heat stress and vibration. Intensity of heat stress was high in melting, pouring and cast shakeout and finishing, with the level of 30 degrees C, 29 degrees C and 26 degrees C, respectively. Noise was high in cast shakeout and finishing and core-making, with the level of 93.1 dB(A) and 89.5 dB(A), respectively. Vibration existed in core-making and cast shakeout and finishing. Compulsory postures included long standing, seating and bowing.
CONCLUSIONOccupational hazards in environment of the foundry are diversified and their concentrations exceed permissible exposure limits stipulated by the national occupational hygienic standards. High-concentrations of dust, metal fume, low-concentrations of variety of chemicals, high-intensity of noise and vibration, heat stress, and harmful compulsory posture, and so on all co-exist in the foundry. Control and protective measures should be strengthened.
Dust ; analysis ; Hazardous Substances ; analysis ; Metallurgy ; Occupational Exposure
10.Developing a Best-Evidence Pre-employment Medical Examination: An Example from the Construction Industry.
Vincent GOUTTEBARGE ; Henk F VAN DER MOLEN ; Monique H W FRINGS-DRESEN ; Judith K SLUITER
Safety and Health at Work 2014;5(3):165-167
The Dutch construction industry has introduced a compulsory preemployment medical examination (PE-ME). Best-evidence contents related to specific job demands are, however, lacking and need to be gathered. After the identification of job demands and health problems in the construction industry (systematic literature search and expert meeting), specific job demands and related requirements were defined and instruments proposed. Finally, a work ability assessment was linked to the instruments' outcomes, resulting in the modular character of the developed PE-ME. Twenty-two specific job demands for all Dutch construction jobs were identified, including kneeling/squatting, working under time pressure, and exposure to hazardous substances. The next step was proposing self-report questions, screening questionnaires, clinical tests, and/or performance-based tests, leading to a work ability judgment. "Lifting/carrying" is described as an example. The new modular PE-ME enables a job-specific assessment of work ability to be made for more than 100 jobs in the Dutch construction industry.
Construction Industry*
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Hazardous Substances
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Judgment
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Mass Screening
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Surveys and Questionnaires