[The history of compensation system for workers with pneumoconiosis-related lung cancer].

Objective: To review the historical aspects of compensation system for workers with pneumoconiosis who developed lung cancer.

Methods: Materials and papers published on the compensation system as discussed in administrative meetings were utilized.

Results: Legal claims for compensation for lung cancer among individuals with pneumoconiosis increased during the period of rapid economic growth in Japan.

Potential role of mitochondrial damage and S9 mixture including metabolic enzymes in ZnO nanoparticles-induced oxidative stress and genotoxicity in Chinese hamster lung (CHL/IU) cells.

The present study was designed to examine genotoxicity induced by 10-40 nm zinc oxide (ZnO) nanoparticles using the in vitro system. The frequency of micronuclei was significantly increased in a dose-dependent manner when cultured Chinese hamster lung (CHL/IU) cells were exposed to ZnO nanoparticles for 24, 48 and 72 h in the continuous treatment method. The maximal frequency of micronuclei was observed in exposure of CHL/IU cells to ZnO nanoparticles at a concentration of 125 μM.

Evaluation of personal exposure of workers to indium concentrations in total dust and its respirable fraction at three Japanese indium plants.

This study aimed to evaluate personal exposures of 27 workers to indium compounds as "total" dust and its "respirable" fraction in their breathing zones at 3 Japanese indium plants. Eight-hour time-weighted average (TWA) indium concentrations of personal exposure to dust collected in sampling periods of 6 h or longer were determined by ICP-MS. The arithmetic means of exposure concentrations were 0.

Quantitative assessment of occupational exposure to total indium dust in Japanese indium plants.

This study quantitatively assessed personal exposure of 86 workers to indium compounds as total dust at 11 Japanese indium plants. The personal exposures to indium concentrations in the breathing zone during an 8 h work-shift were determined by ICP-MS. The arithmetic mean indium concentration of all the workers was 0.

Control banding assessment of workers' exposure to indium and its compounds in 13 Japanese indium plants.

Objectives: This study aimed to assess workers' exposure to indium and its compounds in 55 indium-handling operations among 13 Japanese plants. The surveyed plants were selected from indium-manufacturing plants whose annual indium production exceeded 500 kg.

Methods: The Control of Substances Hazardous to Health (COSHH) Essentials control banding toolkit, which contains simple scales for hazard levels, quantities in daily use, and "dustiness" characteristics, was used to assess generic risks of indium-handling operations.

Development of a method for monitoring personal exposure to benzyl violet 4B and direct blue 15 in workplace air.

Objectives: The purpose of this research was to develop a method for monitoring personal exposure to benzyl violet 4B (BV) and direct blue 15 (DB) in workplace air for risk assessment.

Methods: We evaluated the utility of the proposed method by examining the following: recovery; method limit of quantification; reproducibility; and storage stability of the samples.

Results: An air sampling cassette containing a glass fiber filter was chosen as the sampler.

Assessment of workplace air concentrations of formaldehyde during and before working hours in medical facilities.

Workplace air concentrations of formaldehyde (FA) in medical facilities where FA and FA-treated organs were stored and handled were measured before and during working hours and assessed by the official method specified by Work Environment Measurement Law. Sixty-percent of the total facilities examined were judged as inappropriately controlled work environment. The concentrations of FA before working hours by spot sampling were found to exceed 0.

[A survey on the use of respirators among dust workers in outdoor working environments].

Objectives: The aim of this survey was to clarify the current status of the use of respirators among dust workers in outdoor working environments.

Methods: The participants were 38 male workers exposed to dust, who were engaged in arc welding or quarrying in outdoor working environments. We interviewed participants about wearing and storage of respirators on site.

Tempol suppresses micronuclei formation in astrocytes of newborn rats exposed to 50-Hz, 10-mT electromagnetic fields under bleomycin administration.

A number of epidemiological studies have suggested that exposure to environmental and occupational electromagnetic fields (EMFs) contribute to the induction of brain tumors. The aim of this study was to investigate the mutagenetic effects of co-exposure to 50-Hz, 10-mT EMFs and bleomycin (BLM) using an ex vivo newborn rat astrocyte micronucleus assay. We also investigated whether the mutagenetic effects of EMFs were related to active oxygen species by using 4-hydroxy-2,2,6,6-tetramethyl piperidine-1-oxyl (tempol), a superoxide radical scavenger.

A longitudinal study on Raynaud's phenomenon in workers using an impact wrench.

Objectives: The purpose of this study was to clarify the occurrence of Raynaud's phenomenon among workers using an impact wrench for a long time.

Methods: The subjects were 704 workers regularly using an impact wrench and taking special medical examinations for vibration syndrome from 1981 to 2008. Raynaud's phenomenon was observed in 39 subjects during the observation period.

Indium chloride-induced micronuclei in in vivo and in vitro experimental systems.

Objectives: The aim of this study was to investigate the genotoxic effects of indium trichloride (InCl(3)·4H(2)O; InCl(3)) using the in vivo bone marrow micronucleus test and the in vitro CHL/IU cell micronucleus test.

Method: BALB/c mice were administered a single intraperitoneal (i.p.

[Occupational poisoning and biological exposure monitoring].

Biological exposure monitoring is available for detecting occupational toxic chemicals. It is possible to evaluate the exposure and adverse effects induced such the occupational toxic chemicals with biological exposure monitoring. It is used in health examination, for the recommendation of occupational exposure limits based on biological exposure monitoring, and for biological exposure indices of the American Conference of Governmental Industrial Hygienists (ACGIH).

The micronucleus test and erythropoiesis: effects of cyclic adenosine monophosphate (cAMP) on micronucleus formation.

The aim of this study was to determine the mechanism of the rodent bone marrow micronucleus test in relation to erythropoiesis. We have previously reported that an acceleration of erythropoiesis increases the frequency of micronucleated polychromatic erythrocytes (MPCE) induced by mutagens. The blood plasma erythropoietin level increased after the injection of N6-2-O-dibutyladenosine-3',5'-cyclic monophosphate into adenosine 3',5'-cyclic monophosphate (cAMP) at a dose of 500 mg/kg.

Geonotoxicity study of illegal drug MDMA and its nitroso derivative N-MDMA by micronucleus and chromosomal aberration tests using Chinese hamsger lung fibroblast cell line.

Objectives: An increase in incidence of the illegal use of tablets containing 3,4-methylenedioxymethamphetamine hydrochloride (MDMA) has recently become a widespread social problem. MDMA ingested orally reacts with nitrite in the stomach and is synthesized intoN-nitroso-3,4-methylenedioxymethamphetamine (N-MDMA). The aim of this study is to investigate the genotoxic effects of MDMA and N-MDMA on the basis of the results of an in vitro micronucleus (MN) test and an in vitro chromosomal aberration (CA) test using a Chinese hamster lung fibroblast cell line (CHL/IU).

Effect of static magnetic field on the induction of micronuclei by some mutagens.

Objectives: It is important to assess the risk of static magnetic fields (SMFs) on human health, because epidemiological studies have indicated that SMFs play a role in the development of diseases such as leukemia and brain tumor. In our environment, we have numerous chances to be exposed to not only SMFs but also many chemicals containing mutagens. The aim of this study is to investigate the effect of SMFs on the induction of micronuclei induced by some mutagens.

Genotoxic effects of N-nitrosoketamine and ketamine as assessed by in vitro micronucleus test in Chinese hamster lung fibroblast cell line.

Objectives: Ketamine hydrochloride (KT) is a secondary amine that has been safely used as an injectable anesthetic and analgesic to avoid the production of nitroso compounds in the stomach. However, ketamine in the tablet form has recently become an abused, recreational drug. The aim of this study was to investigate the genotoxic effects of N-nitrosoketamine (NKT) and KT on the basis of an in vitro micronucleus (MN) test using a Chinese hamster lung fibroblast cell line (CHL/IU).

The frequencies of micronuclei induced by cisplatin in newborn rat astrocytes are increased by 50-Hz, 7.5- and 10-mT electromagnetic fields.

Objectives: Epidemiological studies have suggested that exposure to environmental and occupational electromagnetic fields (EMFs) contribute to the induction of brain tumors, leukemia, and other neoplasms. The aim of this study was to investigate the genotoxic effects of exposure to 50-Hz EMFs. and of co-exposure to cisplatin, a mutagen and carcinogen, and 50-Hz EMFs, using an in vivo newborn rat astrocyte micronucleus assay.

[The state and results of countermeasures for mental health at a certain apparel company].

We speculated that there would be more occupational stress in an apparel company than in other areas of business, because employees work long hours and under poor conditions. We investigated 66 employees of an apparel company who visited an occupational physician to consult about their mental health. There were 561 male and 387 female employees in that company.

[Investigation of the health condition of the "shukko" person in a certain Japanese company].

The influence of the "shukko" (temporary transfer) work system on health was examined. "Shukko" is a Japanese individual work system. The life-time employment system was general in Japan.