http://www.occup-med.com The latest research articles published by Journal of Occupational Medicine and Toxicology 2012-01-22T00:00:00Z Background: A major cause of the hearing loss following exposure to intense noise involves release of free radicals resulting from the elevated metabolism. The free radicals induce damage to several of the components of the cochlear amplifier including the outer hair cells and indirectly to the transduction currents. Salicylic acid induces a reversible hearing loss since it binds to the motor protein prestin in the outer hair cells, reducing electromotility. Furosemide also induces a reversible hearing loss since it reduces the endocochlear potential which is a major component of the cochlear transduction currents. On the other hand, each of these drugs also provides protection from a noise induced hearing loss if they are injected just before a noise exposure, probably as a result of the decreased metabolism induced in their presence, with release of lower levels of free radicals. In this study, both drugs were administered in order to assess whether their protective effects would be additive. Methods: The study was conducted on normal hearing albino mice of the Sabra strain. They were injected with either salicylic acid alone (N=11), or furosemide alone (N=14), or both together (N=14), or with saline control (N=11) and exposed to broad band noise for 3.5 hours. An additional group of 9 mice was injected with both salicylic acid and furosemide, but not exposed to noise. The degree of the resulting hearing loss was assessed by recording thresholds of the auditory nerve brainstem evoked responses to broad band clicks before the injections and noise, and 7, 14 and 21 days after. Results: The noise induced hearing loss in the mice injected with salicylic acid alone or furosemide alone was smaller than those injected with saline, i.e. these drugs provided protection, as in previous studies in this laboratory. There was no threshold elevation after two weeks in the mice injected with both drugs without noise exposure, i.e. the effects of the two drugs given together was reversible. On the other hand, there was a significant hearing loss (i.e. threshold elevation) in the group which received both drugs and was also exposed to noise, with mean threshold elevations of 38.8 +/- 19.0 dB and 28.3 +/- 11.7 dB 7 days after noise exposure. Conclusions: This result is very surprising, if not paradoxical. Drugs which provide protection from a noise induced hearing loss when administered alone, not only do not provide protection when given together, but also induce a greater hearing loss when accompanied by noise. This observation may be related to the finding that the depression of the endocochlear potential normally caused by furosemide is reduced in the presence of salicylic acid, so that the protection usually provided by furosemide is not present when it is administered together with salicylic acid. Thus it seems that each drug may interfere with the protective action of the other when coupled with noise. http://www.occup-med.com/content/7/1/1 Marrigje de Jong Cahtia Adelman Melissa Rubin Haim Sohmer Journal of Occupational Medicine and Toxicology 2012, null:1 2012-01-22T00:00:00Z doi:10.1186/1745-6673-7-1 /content/figures/1745-6673-7-1-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 1 2012-01-22T00:00:00Z PDF Background: Exposure to continuous and impulse noise can induce a hearing loss. Leupeptin is an inhibitor of the calpains, a family of calcium-activated proteases which promote cell death. The objective of this study is to assess whether Leupeptin could reduce the hearing loss resulting from rifle impulse noise. Methods: A polyethelene tube was implanted into middle ear cavities of eight fat sand rats (16 ears). Following determination of auditory nerve brainstem evoked response (ABR) threshold in each ear, the animals were exposed to the noise of 10 M16 rifle shots. Immediately after the exposure, saline was then applied to one (control) ear and non-toxic concentrations of leupeptin determined in the first phase of the study were applied to the other ear, for four consecutive days. Results: Eight days after the exposure, the threshold shift (ABR) in the control ears was significantly greater (44 dB) than in the leupeptin ears (27 dB). Conclusion: Leupeptin applied to the middle ear cavity can reduce the hearing loss resulting from exposure to impulse noise. http://www.occup-med.com/content/6/1/38 Haim Gavriel Abraham Shulman Alfred Stracher Haim Sohmer Journal of Occupational Medicine and Toxicology 2011, null:38 2011-12-29T00:00:00Z doi:10.1186/1745-6673-6-38 /content/figures/1745-6673-6-38-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 38 2011-12-29T00:00:00Z PDF Background: The study investigates whether established inpatient therapy for teachers with burnout results in long-acting success and whether gender gaps and differences between teachers of different school levels exist. According to our knowledge, our study is the most extensive inpatient intervention study on the burnout of a defined occupational group, i.e., teachers. Methods: 200 teachers participated, 150 took part in a later performed katamnestic survey. The Maslach Burnout Inventory (MBI) was used and work-related data were recorded. Results: The days of incapacity for work and the percentage of teachers endangered by burnout decreased. Significant MBI-differences between males and females and between teacher levels were found. The differences between teacher levels only showed up before treatment. Because males only underwent treatment at a more severe stage, further efforts in persuading males to start therapy earlier are needed. Conclusions: The proven and long-term success of the performed intervention could have greater effects if people, especially males, undergo treatment more frequently. Our results are based on a selectively high proportion of teachers of advanced age. Thus it is possible that the long term effect of the intervention, particularly on retirement age, is greater when the intervention is started earlier. Regular burnout tests could help to identify risk cases among teachers at an early stage and to offer a therapeutic intervention. http://www.occup-med.com/content/6/1/37 Ralf Wegner Peter Berger Bernd Poschadel Ulf Manuwald Xaver Baur Journal of Occupational Medicine and Toxicology 2011, null:37 2011-12-22T00:00:00Z doi:10.1186/1745-6673-6-37 /content/figures/1745-6673-6-37-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 37 2011-12-22T00:00:00Z PDF Background: Working conditions of nursery school teachers have not been scrutinized thoroughly in scientific research. Only a few studies have so far examined work-load and strain in this profession. Preferably, subjective perceptions should be corroborated by data that can be quantified more objectively and accurately. The aim of the present observational field study was to evaluate pedagogical staffs' workflow. Methods: In 2009 eleven educators in a day care centre were observed throughout three complete workdays. A total of 250 working hours were recorded. Results: An educators' workday lasted on average 07:46:59 h (SD = 01:01:10 h).Within this time span, an average of 02:20:46 h (30.14%, SD = 00:28:07 h) were spent on caring, 01:44:18 h on playing (22.33%, SD = 00:54:12 h), 00:49:37 h on educational work (10.62%, SD = 00:40:09), and only 00:05:38 h on individual child contact (1.21%, SD = 00:04:58 h). Conclusion: For the first time, educators' workflow in day care centres was studied in real time. Some of the educators' self-reported problems were corroborated. The results of this study form a basis upon which further investigations can be built and measures can be developed for an overall improvement of child care. http://www.occup-med.com/content/6/1/36 Bianca Kusma Stefanie Mache David Quarcoo Albert Nienhaus David Groneberg Journal of Occupational Medicine and Toxicology 2011, null:36 2011-12-22T00:00:00Z doi:10.1186/1745-6673-6-36 /content/figures/1745-6673-6-36-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 36 2011-12-22T00:00:00Z PDF Environmental tobacco smoke (ETS) is a major contributor to indoor air pollution. Since decades it is well documented that ETS can be harmful to human health and causes premature death and disease. In comparison to the huge research on toxicological substances of ETS, less attention was paid on the concentration of indoor ETS-dependent particulate matter (PM). Especially, investigation that focuses on different tobacco products and their concentration of deeply into the airways depositing PM-fractions (PM10, PM2.5 and PM1) must be stated. The tobacco smoke particles and indoor air quality study (ToPIQS) will approach this issue by device supported generation of indoor ETS and simultaneously measurements of PM concentration by laser aerosol spectrometry. Primarily, the ToPIQ study will conduct a field research with focus on PM concentration of different tobacco products and within various microenvironments. It is planned to extend the analysis to basic research on influencing factors of ETS-dependent PM concentration. http://www.occup-med.com/content/6/1/35 Daniel Mueller Stefanie Uibel Markus Braun Doris Klingelhoefer Masaya Takemura David Groneberg Journal of Occupational Medicine and Toxicology 2011, null:35 2011-12-21T00:00:00Z doi:10.1186/1745-6673-6-35 /content/figures/1745-6673-6-35-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 35 2011-12-21T00:00:00Z XML Copper sulphate ingestion (accidental or deliberate) is a rare form of poisoning usually limited to the Indian subcontinent. Though the rates are on the decline, it is essential that physicians are aware of its lethal complications and management strategies. The main complications of copper sulphate ingestion include intravascular haemolysis, methaemoglobinaemia, acute kidney injury and rhabdomyolysis. The lethal dose can be as small as 10 grams. We have explored the complications of acute copper sulphate poisoning with examples from two case presentations. We also recommend measures for prevention of such events. http://www.occup-med.com/content/6/1/34 Champika Gamakaranage Chaturaka Rodrigo Sajitha Weerasinghe Ariaranee Gnanathasan Visvalingam Puvanaraj Harshani Fernando Journal of Occupational Medicine and Toxicology 2011, null:34 2011-12-19T00:00:00Z doi:10.1186/1745-6673-6-34 /content/figures/1745-6673-6-34-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 34 2011-12-19T00:00:00Z XML The population of industrialized countries such as the United States or of countries from the European Union spends approximately more than one hour each day in vehicles. In this respect, numerous studies have so far addressed outdoor air pollution that arises from traffic. By contrast, only little is known about indoor air quality in vehicles and influences by non-vehicle sources.Therefore the present article aims to summarize recent studies that address i.e. particulate matter exposure. It can be stated that although there is a large amount of data present for outdoor air pollution, research in the area of indoor air quality in vehicles is still limited. Especially, knowledge on non-vehicular sources is missing. In this respect, an understanding of the effects and interactions of i.e. tobacco smoke under realistic automobile conditions should be achieved in future. http://www.occup-med.com/content/6/1/33 Daniel Mueller Doris Klingelhoefer Stefanie Uibel David Groneberg Journal of Occupational Medicine and Toxicology 2011, null:33 2011-12-16T00:00:00Z doi:10.1186/1745-6673-6-33 /content/figures/1745-6673-6-33-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 33 2011-12-16T00:00:00Z XML Background: The work- or environmental-related type I sensitization to maize pollen is hardly investigated. We sought to determine the prevalence of sensitization to maize pollen among exposed workers and to identify the eliciting allergens. Methods: In July 2010, 8 out of 11 subjects were examined who were repeatedly exposed to maize pollen by pollinating maize during their work in a biological research department. All 8 filled in a questionnaire and underwent skin prick testing (SPT) and immune-specific analyses. Results: 5 out of the 8 exposed subjects had repeatedly suffered for at least several weeks from rhinitis, 4 from conjunctivitis, 4 from urticaria, and 2 from shortness of breath upon occupational exposure to maize pollen. All symptomatic workers had specific IgE antibodies against maize pollen (CAP class ≥ 1). Interestingly, 4 of the 5 maize pollen-allergic subjects, but none of the 3 asymptomatic exposed workers had IgE antibodies specific for grass pollen. All but one of the maize pollen-allergic subjects had suffered from allergic grass pollen-related symptoms for 6 to 11 years before job-related exposure to maize pollen. Lung function testing was normal in all cases. In immunoblot analyses, the allergenic components could be identified as Zea m 1 and Zea m 13. The reactivity is mostly caused by cross-reactivity to the homologous allergens in temperate grass pollen. Two sera responded to Zea m 3, but interestingly not to the corresponding timothy allergen indicating maize-specific IgE reactivity. Conclusion: The present data suggest that subjects pollinating maize are at high risk of developing an allergy to maize pollen as a so far underestimated source of occupational allergens. For the screening of patients with suspected maize pollen sensitization, the determination of IgE antibodies specific for maize pollen is suitable. http://www.occup-med.com/content/6/1/32 Marcus Oldenburg Arnd Petersen Xaver Baur Journal of Occupational Medicine and Toxicology 2011, null:32 2011-12-13T00:00:00Z doi:10.1186/1745-6673-6-32 /content/figures/1745-6673-6-32-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 32 2011-12-13T00:00:00Z XML The duration of use is usually significantly longer for marine vessels than for roadside vehicles. Therefore, these vessels are often powered by relatively old engines which may propagate air pollution. Also, the quality of fuel used for marine vessels is usually not comparable to the quality of fuels used in the automotive sector and therefore, port areas may exhibit a high degree of air pollution. In contrast to the multitude of studies that addressed outdoor air pollution due to road traffic, only little is known about ship-related air pollution. Therefore the present article aims to summarize recent studies that address air pollution, i.e. particulate matter exposure, due to marine vessels. It can be stated that the data in this area of research is still largely limited. Especially, knowledge on the different air pollutions in different sea areas is needed. http://www.occup-med.com/content/6/1/31 Daniel Mueller Stefanie Uibel Masaya Takemura Doris Klingelhoefer David Groneberg Journal of Occupational Medicine and Toxicology 2011, null:31 2011-12-05T00:00:00Z doi:10.1186/1745-6673-6-31 /content/figures/1745-6673-6-31-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 31 2011-12-05T00:00:00Z XML Background: Professional working at computer notebooks is associated with high requirements on the body posture in the seated position. By the high continuous static muscle stress resulting from this position at notebooks, professionals frequently working at notebooks for long hours are exposed to an increased risk of musculoskeletal complaints. Especially in subjects with back pain, new notebooks should be evaluated with a focus on rehabilitative issues. Methods: In a field study a new notebook design with adjustable screen was analyzed and compared to standard notebook position. Results: There are highly significant differences in the visual axis of individuals who are seated in the novel notebook position in comparison to the standard position. Also, differences are present between further alternative notebook positions. Testing of gender and glasses did not reveal influences. Conclusion: This study demonstrates that notebooks with adjustable screen may be used to improve the posture. Future studies may focus on patients with musculoskeletal diseases. http://www.occup-med.com/content/6/1/30 David Quarcoo Cristian Scutaru Ulrich Henkel Michael Spallek Stefanie Uibel Karin Vitzthum Stefanie Mache Bianca Kusma David Groneberg Journal of Occupational Medicine and Toxicology 2011, null:30 2011-11-25T00:00:00Z doi:10.1186/1745-6673-6-30 /content/figures/1745-6673-6-30-toc.gif Journal of Occupational Medicine and Toxicology 1745-6673 ${item.volume} 30 2011-11-25T00:00:00Z XML