Occupational disease hazards in plywood manufacturing mainly include wood dust, formaldehyde, phenol, ammonia, noise, terpene, microorganisms, etc. The exposure is complex with multiple factors accompanied or coexisted. In the production process, these factors are exceeded, and mass occupational disease hazard events occurred among workers. Exposure to wood dust, formaldehyde, terpene, etc., put workers at increased risk of cancer. This article provides a review of this issue in order to provide a scientific basis for the prevention and control of occupational disease hazards in plywood manufacturing.
Humans ; Wood/chemistry* ; Occupational Diseases/chemically induced* ; Formaldehyde/adverse effects* ; Terpenes ; Dust ; Occupational Exposure/adverse effects*

The present review summarizes the results of several follow-up studies assessing an asbestos product manufacturing plant in Chongqing, China, and discusses three controversial issues related to the carcinogenicity of asbestos. The first issue is the amphibole hypothesis, which asserts that the carcinogenicity of asbestos is limited to amphiboles, such as crocidolite, but not serpentines, such as chrysotile. However, considering the possible multiple component of asbestos carcinogenicity in the presence of tobacco smoke or other carcinogens, chrysotile cannot be regarded as non-carcinogenic. Additionally, in a practical sense, it is not possible to assume "pure" chrysotile due to its ubiquitous contamination with tremolite, which is a type of amphibole. Thus, as the International Agency for Research on Cancer (IARC) assessed, all forms of asbestos including chrysotile should be regarded carcinogenic to humans (Group 1). The second issue is the chrysotile/tremolite paradox, which is a phenomenon involving predominant levels of tremolite in the lung tissues of individuals who worked in locations with negligible levels of tremolite due to the exclusive use of chrysotile. Four possible mechanisms to explain this paradox have been proposed but this phenomenon does not support the claim that amphibole is inert. The final issue discussed is the textile mystery, i.e., the higher incidence of cancer in asbestos textile plants compared to asbestos mines where the same asbestos was produced and the exposure levels were comparable. This phenomenon was first reported in North America followed by UK and then in the present observations from China. Previously, levels of fiber exposure were calculated using a universal converting coefficient to estimate the mass concentration versus fiber concentration. However, parallel measurements of fiber and mass concentrations in the workplace and exposed air indicated that there are wide variations in the fiber/mass ratio, which unjustifies the universal conversion. It is possible that contamination by airborne non-fibrous particles in mines with mass fiber conversion led to the overestimation of fiber concentrations and resulted in the textile mystery. Although the use and manufacturing of asbestos has been banned in Japan, more than 10 million tons of asbestos had been imported and the majority remains in existing buildings. Thus, efforts to control asbestos exposure should be continued.
Asbestos ; classification ; toxicity ; Asbestos, Amphibole ; toxicity ; Asbestos, Serpentine ; toxicity ; Carcinogens ; China ; Follow-Up Studies ; Humans ; Lung Neoplasms ; chemically induced ; epidemiology ; Manufacturing and Industrial Facilities ; statistics & numerical data ; Mining ; statistics & numerical data ; Occupational Diseases ; epidemiology ; Occupational Exposure ; adverse effects ; Textiles ; Tobacco Smoking ; epidemiology

BACKGROUND: Plastic resins are complex chemicals that contain toluene diisocyanate (TDI) and/or trimellitic anhydride (TMA), which cause occupational allergies (OA), including respiratory allergies. Serum IgGs against TDI and TMA have been suggested as potential markers of the exposure status and as exploring cause of OA. Although TDI-specific IgG has been examined for suspected OA, TMA-specific IgG is not commonly evaluated in a urethane foam factory. This study therefore investigated both TDI- and TMA-specific IgGs in suspected OA patients and to evaluate the usefulness of the measurement of multiple chemical-specific IgG measurement for practical monitoring. METHODS: Blood samples were collected from two male workers who developed respiratory allergies supposedly caused by occupational exposure to TDI and/or TMA for the presence of TDI- and TMA-specific IgGs. In addition, blood samples from 75 male workers from a urethane foam factory, along with 87 male control subjects, were collected in 2014 and tested for the same IgGs in 2014. The presence and levels of TDI- and TMA-specific serum IgGs were measured using dot blot assays. RESULTS: We found that controls had mean concentrations of TDI- and TMA-specific IgGs of 0.98 and 2.10 μg/mL, respectively. In the two workers with respiratory allergies, the TDI-specific IgG concentrations were 15.6 and 9.51 μg/mL, and TMA-specific IgG concentrations were 4.56 and 14.4 μg/mL, which are clearly higher than those in controls. Mean concentrations of TDI- and TMA-specific IgGs in the factory workers were 1.89 and 2.41 μg/mL, respectively, and are significantly higher than those of the controls (P < 0.001 and P < 0.026 for TDI- and TMA-specific IgGs, respectively). CONCLUSION The workers suspected of OA showed an evidently high level of TDI- and TMA-specific IgG, and these levels in workers at the urethane foam factory were also significantly higher than those in controls. In conclusion, the measurement of TDI- and TMA-specific IgG among workers using plastic resins is helpful to monitor their exposure status.
Adult ; Air Pollutants, Occupational ; adverse effects ; immunology ; Environmental Monitoring ; Humans ; Immunoglobulin G ; blood ; immunology ; Japan ; Male ; Manufacturing and Industrial Facilities ; statistics & numerical data ; Middle Aged ; Occupational Diseases ; blood ; chemically induced ; Occupational Exposure ; adverse effects ; statistics & numerical data ; Phthalic Anhydrides ; immunology ; toxicity ; Respiratory Hypersensitivity ; blood ; chemically induced ; Toluene 2,4-Diisocyanate ; immunology ; toxicity ; Workforce

2,4-dinitrophenol (DNP), an organic compound which frequently used in industry, is considered to have high toxicity. This study aimed to investigate the early changes of lymphocyte subpopulations in patients with occupational 2,4-DNP poisoning. Totally 9 patients with acute occupational 2,4-DNP poisoning and 30 healthy volunteers as control were enrolled. The patients received immediately comprehensive supportive treatments, including large-dose glucocorticoid and repeated hemoperfusion (HP). The ratio of CD4+/CD8+ T cells were significantly higher in patients upon admission compared to healthy controls (P < 0.01); however, counts of total lymphocytes, CD3+, CD3+CD4+, CD3+CD8+, B (CD19+), and natural killer (NK) cells (CD16+CD56+) were significantly reduced (all P < 0.001). The NK cell count was negatively correlated with initial plasma 2,4-DNP concentration (r = -0.750, P = 0.026). Thus, acute occupational 2,4-DNP poisoning was accompanied by immediate complex immune cell reactions, especially NK cells might play important role in severe 2,4-DNP poisoning.
2,4-Dinitrophenol ; poisoning ; toxicity ; Adult ; China ; Coloring Agents ; poisoning ; toxicity ; Female ; Humans ; Killer Cells, Natural ; drug effects ; Lymphocyte Subsets ; drug effects ; Male ; Middle Aged ; Occupational Diseases ; chemically induced ; T-Lymphocytes ; drug effects

Benzene ; poisoning ; Chronic Disease ; Humans ; Occupational Diseases ; chemically induced ; Occupational Exposure ; adverse effects

OBJECTIVETo understand the toxic effects of manganese exposure on health by measurement of manganese concentration and occupational health inspection among workers in an enterprise exposed to manganese, and to provide a basis for occupational disease control.

METHODSThe air concentrations of manganese in 12 workplaces where workers often stayed were measured by typical sampling; occupational health inspection was performed among a total of 538 workers in the enterprise by cluster sampling.

RESULTSThe average concentrations of manganese in the workplace from 2011 to 2013 were 0.179 mg/m(3), 0.122 mg/m(3), and 0.082 5 mg/m(3), respectively, indicating a significant decrease in manganese level within the three years by rank-sum test (P < 0.05). The results of health inspection showed that 165 (30.7%) out of 538 workers had abnormal indices, and the incidence of autonomic nervous system abnormalities reached 32.7% (176/538). There was no correlation between manganese concentration in the workplace and the incidence of abnormal indices in health inspection, while the manganese concentration in the workplace was positively correlated with the incidence of autonomic nervous system symptoms (r = 0.718, P < 0.05).

CONCLUSIONThe manganese concentration in the workplace is positively correlated with the incidence of autonomic nervous system symptoms. Early exposure to a low level of manganese can induce functional changes and potential damages in the nervous system.

Humans ; Incidence ; Manganese ; analysis ; Nervous System ; drug effects ; physiopathology ; Occupational Diseases ; chemically induced ; epidemiology ; Occupational Exposure ; analysis ; Occupational Health ; standards ; Workplace

To determine the correlation between the working environment and the health status of employees in solar greenhouse, 1171 employees were surveyed. The results show the 'Greenhouse diseases' are affected by many factors. Among general uncomforts, the morbidity of the bone and joint damage is the highest and closely related to labor time and age. Planting summer squash and wax gourd more easily cause skin pruritus. Asthma-related cough, eye disease, and skin pruritus are significantly correlated with the cultivation of wax gourd. The application of inorganic fertilizer and fertigation dramatically induce the bone and joint damage. The smell of covering film greatly influence skin pruritus. Personal protection is badly scanty and normative occupational health and safety need to be completed.
Adult ; Asthma ; chemically induced ; Cough ; chemically induced ; Crops, Agricultural ; Educational Status ; Environment, Controlled ; Eye Diseases ; chemically induced ; Fertilizers ; toxicity ; Humans ; Middle Aged ; Nose Diseases ; chemically induced ; Occupational Exposure ; Pesticides ; toxicity ; Pruritus ; chemically induced ; Risk Factors ; Stomach Diseases ; chemically induced ; Workplace

Investigation into the frequency of compensation for occupational diseases (ODs) caused by hazardous chemicals revealed an important opportunity for the improvement and further development of occupational health and safety systems in Korea. In response to concerns after outbreaks of disease due to chemical exposure, specific criteria for recognition of ODs were established and included in the Enforcement Decree of the Labor Standard Act (LSA) and the Industrial Accident Compensation Insurance Act (IACIA) on June 28, 2013. However, the original versions of the LSA and IACIA contain several limitations. First, the criteria was listed inconsistently according to the symptoms or signs of acute poisoning. Second, all newly recognized hazardous chemicals and chemicals recognized as hazardous by the International Labor Organization (ILO) were not included in the LSA and IACIA. Although recent amendments have addressed these shortcomings, future amendments should strive to include all chemicals listed by the ILO and continuously add newly discovered hazardous chemicals as they are introduced into the workplace.
Adolescent ; Burns, Chemical/economics ; Female ; Humans ; Metals, Heavy/economics/poisoning ; Occupational Diseases/*chemically induced/*economics ; Occupational Exposure/*adverse effects ; Poisoning/economics ; Republic of Korea ; Workers' Compensation/*economics

Occupational diseases may be defined only medically or scientifically, and even then, their definition is not simple. However, compensable occupational diseases involve the additional layer of legal systems and social welfare policies as well. Their multifaceted nature makes determining the work-relatedness of these diseases more complex. Korea has established standards for the recognition of occupational diseases in Schedule 5 of the Enforcement Decree of the Labor Standards Act, and specific criteria for the recognition of occupational diseases are listed in Schedule 3 of the Enforcement Decree of the Industrial Accident Compensation Insurance Act. The new list of compensable occupational diseases comprises 13 articles as an open-ended system. The newly added articles pertain to lymphohematopoietic (Article 5) and infectious diseases (Article 9), as well as diseases of other target organs. Furthermore, the article on liver diseases (Article 8) has been partially revised. The new act has been changed to clarify the meaning as it has been presented in recent research. It is necessary to achieve agreement among concerned parties, including experts from the legal, medical, and social domains to resolve the issues of work-relatedness, causation, notion of aggravation, and so on for preparing a list and a process that are more reasonable.
Adult ; Benzene/toxicity ; Communicable Diseases/*economics ; Dimethylformamide/toxicity ; Drug-Induced Liver Injury/economics ; Female ; Hematologic Diseases/chemically induced/*economics ; Humans ; Lead/toxicity ; Liver Diseases/*economics ; Male ; Middle Aged ; Occupational Diseases/*economics ; Republic of Korea ; Trichloroethylene/toxicity ; Vinyl Chloride/toxicity ; Workers' Compensation/*economics

Standards for the recognition of occupational diseases (ODs) in Korea were established in 1954 and have been amended several times. In 2013, there was a significant change in these standards. On the basis of scientific evidence and causality, the International Labour Organization list, European Commission schedule, and compensated cases in Korea were reviewed to revise the previous standards for the recognition of ODs in Korea. A disease-based approach using the International Classification of Diseases (10th version) was added on the previous standards, which were agent-specific approaches. The amended compensable occupational neurological disorders and occupational mental disorders (OMDs) in Korea are acute and chronic central nervous system (CNS) disorders, toxic neuropathy, peripheral neuropathy, manganese-related disorders, and post-traumatic stress disorder. Several agents including trichloroethylene (TCE), benzene, vinyl chloride, organotin, methyl bromide, and carbon monoxide (CO) were newly included as acute CNS disorders. TCE, lead, and mercury were newly included as chronic CNS disorders. Mercury, TCE, methyl n-butyl ketone, acrylamide, and arsenic were newly included in peripheral neuropathy. Post-traumatic stress disorders were newly included as the first OMD. This amendment makes the standard more comprehensive and practical. However, this amendment does not perfectly reflect the recent scientific progress and social concerns. Ongoing effort, research, and expert consensus are needed to improve the standard.
Female ; Humans ; Mental Disorders/chemically induced/*economics/pathology ; Nervous System Diseases/chemically induced/*economics/pathology ; Occupational Diseases/*economics ; Occupational Exposure ; Republic of Korea ; Stress Disorders, Post-Traumatic/diagnosis/*economics ; Workers' Compensation/*economics