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Objective: To get insight into the current practice of noise reduction effect of workers as they wore hearing protectors in different domestic enterprises and the possible affected factors. Methods: From October 2020 to April 2021, using a random sampling method, 1197 workers exposed to noise in petrochemical factories, textile factories, and parts manufacturing factories were selected as the study subjects. The noise reduction effect of hearing protectors worn by workers in daily use was tested using a hearing protector suitability testing system. The personal sound attenuation level (PAR) was compared among workers in three enterprises, Targeted intervention and repetitive testing were conducted for workers who did not meet the noise reduction effect required by the enterprise, and the changes in PAR of workers before and after the intervention were compared. The comparison of baseline PARs between two or more groups was performed using the Mann Whitney test, the comparison of baseline PARs with post intervention PARs was performed using the Wilcoxon signed rank sum test, and the comparison of qualitative data between two or more groups was performed using the Chi square test. Results: The median baseline PAR for all workers was 15 dB. Men, age<30 years old, education level at or above college level, working experience of 5 to 15 years, and those who used hearing protectors for 5 to 15 years had higher PARs, with statistically significant differences (P<0.05). The median difference in baseline PAR among workers from three enterprises was statistically significant (H=175.06, P<0.01). The median PAR of subjects who did not pass the baseline increased from 3 dB to 21 dB after intervention (Z=-27.92, P<0.01) . Conclusion: Some workers wearing hearing protectors do not meet the required PAR, and low PARs may be related to incorrect wearing methods and incorrect selection of hearing protectors. As a tool for testing, training, and assisting in selection, the hearing protector suitability testing system is of great significance for worker hearing protection.
Subject(s)
Male , Humans , Adult , Hearing Loss, Noise-Induced/prevention & control , Ear Protective Devices , Noise, Occupational/prevention & control , Hearing , AudiometryABSTRACT
Objective: To analyze the level of PCDD/Fs exposure of occupational workers in the waste incineration industry and explore the risk of occupational exposure. Methods: In September 2021, literature on environmental PCDD/Fs exposure in waste incineration plants published from the establishment of the database to February 10, 2021 was retrieved from CNKI database. A total of 1365 literatures were retrieved, and 7 met the criteria for inclusion. The US Environmental Protection Agency (EPA) inhalation risk model was used to assess and analyze carcinogenic and non-carcinogenic risks of PCDD/Fs exposure among occupational workers in the waste incineration industry. Results: A total of 86 sampling sites were included in incineration plants in 7 regions. The study of Wuhan area showed that the concentration of working environment near the waste incinerator in the same factory was the highest, followed by the rest and office area in the factory. The concentration of PCDD/Fs in waste incinerators was the highest in Southwest China (4880.00-24880.00 pg TEQ/m(3)), and the lowest in Shenzhen (0.02-0.44 pg TEQ/m(3)). According to the cancer risk assessment, with the increase of exposure years, the risk of cancer increased. The highest risk of cancer was found in the waste incineration plants in Southwest China. When the exposure period was 1 year, the risk was moderate (22.40×10(-6)-114.20×10(-6)). When the exposure time was more than 5 years, the risk of cancer was high. In Jinan, workers working near the incinerator had a moderate risk of cancer after five years of exposure. In Zhejiang, workers were at medium risk of cancer after exposure for more than 20 years. Workers in Wuhan, Shanghai, Zhejiang Province, Shenzhen and the Pearl River Delta were still at low risk of cancer after 40 years of occupational exposure. HQ>1 of workers working near the waste incinerators in Jinan, Zhejiang Province and Southwest China, and the qualitative evaluation results showed that the non-carcinogenic risk was unacceptable. Conclusion: There are great differences in PCDD/Fs of occupational exposure in waste incineration industry, and the occupational exposure exceeding the occupational exposure limit has higher carcinogenic and non carcinogenic risks.
Subject(s)
Humans , Dibenzofurans , Polychlorinated Dibenzodioxins/analysis , Air Pollutants/analysis , Incineration , Dibenzofurans, Polychlorinated/analysis , China/epidemiology , Benzofurans , Occupational Exposure/analysis , Carcinogens , Risk Assessment , Neoplasms , Environmental Monitoring/methodsABSTRACT
OBJECTIVE: To analyze the skills of using dust mask in the dust-exposed workers in civil metal ship manufacturing enterprises. METHODS: A total of 123 dust-exposed workers in a civil metal ship manufacturing enterprise were selected as the research subjects using convenience sampling method. Dust Mask Using Situation and Maintenance Questionnaire was used to investigate the use of dust masks, and the tightness of using dust mask was measured by the tightness tester. RESULTS: The median, and the 0 th-100 th percentiles[M(P_0-P_(100))] of the dust mask use time in the workers was 3.0(1.0-3.0) months, and the M(P_0-P_(100)) of filter element use time was 1.0(0.5-2.0) workdays. The subjects did not disinfect the masks after use. Only 36.6%(45/123) of workers regularly cleaned dust masks during use. There was 62.6%(77/123) of workers who failed to correctly perform negative pressure air tightness check by themselves. A total of 112 workers carried out tightness test, and the pass rate of those who passed the tightness test for the first time was 62.5%(70/112). The median, and the 25 th and 75 th percentiles [M(P_(25), P_(75))] of fit factor(FF) in the 70 qualified workers was 835.0(503.0, 1 635.0). After retests, the overall tightness test pass rate was 66.1%(74/112), and the M(P_(25), P_(75)) of FF in the 74 qualified workers was 786.0(477.7, 1 532.2). The reasons for failure of tightness test were the mismatch of the mask and face size, wrong wearing methods and long beard. CONCLUSION: Some of the dust-exposed workers in the civil metal ship manufacturing enterprises did not use the dust mask correctly. The dust mask configuration and the use and maintenance training should be strengthened, and the tightness test should be carried out regularly to improve workers′ skills in using dust masks.
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OBJECTIVE: To explore the distribution characteristics of single nucleotide polymorphism(SNP) rs7072793 and rs3118470 in the 5′ flanking region of(cluster of differentiation 25, CD25) gene in Han males in the naturally high radiation background area(HBRA). METHODS: A random sampling method was used to select 48 and 51 healthy Han males from Tangkou town(HBRA group) in Yangjiang City and Hengpo town(control group) in Enping City, respectively, as the study subjects. The molecular mass array method was used to classify the genotype of the SNP sites rs7072793 and rs3118470 of CD25 gene in these subjects. The distribution difference of the alleles and genotypes was analyzed in individuals of these two groups. The allele frequency of HBRA population was compared with the distribution data of different populations in the Human Genome Project.RESULTS: The distribution of allele frequencies of rs7072793 and rs3118470 in both groups were consistent with the H-W equilibrium law of genetics(all P>0.05). In the HBRA group, variant allele C(58.3%) and genotype TC(50.0%) were dominant at rs7072793, wild-type allele T(55.2%) and genotype TC(56.2%) were dominant at rs3118470. There was no significant difference in the allele and genotype distributions between these two groups(all P>0.05). There was a difference of rs7072793 in the HBRA group compared to that of African and European populations, and rs3118470 in the HBRA group compared with the allele distribution frequencies in Africa, Europe and America populations(all P<0.05). CONCLUSION: In the male population of Han nationality in Yangjiang HBRA area, the alleles of rs7072793 and rs3118470 in the 5′ flanking region of CD25 gene were mainly C and T, respectively, and the genotypes were mainly TC. These two loci may have high genetic variability.
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At present, the methods for verifying the attenuation of hearing protective devices(HPDs) mainly include real-ear attenuation at threshold(REAT), microphone in real ear(MIRE), and acoustical test fixture(ATF). Among them, the REAT is the gold standard, but its testing requirements are strict and there is a physiological noise masking effect. The test results of MIRE need to be modified by transfer function of the open ear, which has the advantage of convenient operation without being affected by subjective feelings. The ATF method is mainly used to verify the shape and quality of customized HPDs since its artificial ear design cannot truly reflect the real-ear test situation. The HPD fit testing has been well developed and widely applied abroad, which has been proved to be able to accurately verify and effectively improve the attenuation of workers wearing HPDs. However, relevant research and applications have only been carried out in China in recent years. At present, the main problems in the verification of the protective effect of HPDs in China are as follows: firstly, the measurement is only limited in attenuation and fail to comprehensively consider the applicability and comfort of the HPDs; secondly, a-weighted sound pressure level is mostly used in noise monitoring in China, while the choice of HPDs is based on C-weighted-sound pressure level. The transition between these two has not been established. Future research should be devoted to solve the above problems and help the use of HPDs in preventing the hearing loss of noise-exposed workers.
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OBJECTIVE: To analyze the diagnosis of occupational disease and the detection status of suspected occupational disease and occupational contraindication in recent years in a petrochemical enterprise. METHODS: The data of new cases of occupational disease reported by a petrochemical enterprise from 2008 to 2019, the cases of suspected occupational disease and occupational contraindication from 2015 to 2019 were collected. The related data was descriptively analyzed. RESULTS: A total of 30 new cases of occupational disease were reported in this petrochemical enterprise from 2008 to 2019. Among them, there were 16 cases of occupational noise deafness, 10 cases of chronic occupational benzene poisoning, 2 cases of occupational leukemia caused by benzene, 1 case of occupational solvent gasoline poisoning and 1 case of occupational pneumoconiosis. Among the 30 cases of occupational diseases, 28 cases(93.3%) were related to benzene and noise exposure, and 19 cases(63.3%) came from the chemical and oil refining divisions. From 2015 to 2019 in this petrochemical enterprise, 24 cases of suspected occupational disease were reported, of which 17(70.8%) suspected cases were diagnosed as occupational disease, and 63 cases of occupational contraindication were reported, including 47(74.6%) cases of occupational contraindication caused by noise. CONCLUSION: Benzene and noise should be taken as the key factors of occupational hazard for prevention and control in the petrochemical enterprises, and control measures should be adopted for special operation links and job posts to control the hidden dangers of benzene and noise that exceeds the standard limits.
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OBJECTIVE: To establish an indicator system for risk assessment on occupational dust hazards and verify its application. METHODS: Using Delphi method,two rounds of investigation were made from 30 experts who work on frontline occupational health. The indicator system for risk assessment was established based on the investigation,statistics and boundary value,in fully consideration with the interaction of three basic elements of“dust inherent characteristics-laborers factors-influencing factors”. The indicator system was applied to evaluate the risk of 90 workplaces in the presence of dust occupational risk factors. RESULTS: The positive coefficient of experts' opinion was 90%,and the coefficient of experts' authority was 0. 808. The coefficient of experts' consensus was 0. 50( χ~2= 120. 56,P < 0. 01). The indicator system for risk assessment on occupational hazards of dust factors has been successfully established. This system included three class A indicators,nine class B indicators and twenty-eight class C indicators. The total coincidence rate of assessments on the risk level of occupational dust hazards of workplaces was 60%( Kappa = 0. 452,P < 0. 01). CONCLUSION: This indicator system was objective,scientific and feasible,and could reflect the actual levels of occupational dust hazards.
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<p><b>OBJECTIVE</b>To explore the effects of noise exposure level and cumulative noise exposure (CNE) on the relationship between rs2070424 and rs10432782 SNPs in SOD1 and the susceptibility to noise-induced hearing loss (NIHL).</p><p><b>METHODS</b>A case-control study was performed for investigating the effects of environmental risk factors on the susceptibility to NIHL in 201 sensitive workers and 202 resistant workers.A questionnaire was utilized to investigate the occupational health and to identify the occupational risk factors. The noise exposure levels were detected according to the Chinese standard Measurement of noise in the workplace (GBZ/T 189.8-2007). The peripheral blood samples (5 ml blood for each sample) were from sensitive workers and resistant workers. Genomic DNA was extracted on the basis of the standard procedures of Takara kit. SNPs were detected using standard procedures of TaqMan probe allele identification method.</p><p><b>RESULTS</b>In group exposed to 85 - 92 dB noise (A), the risk of NIHL in the subjects with the AA genotype of rs2070424 was lower than that in the subjects with the GG genotype, OR = 0.37 (95%CI: 0.17∼ 0.80). In group exposed to > 82 dB CNE (A), the AA genotype of rs2070424 is a protective factor of NIHL, as compared with the GG genotype, OR = 0.25 (95%CI: 0.09 ∼ 0.70). In group exposed to 85 - 92 dB noise (A), the risk of NIHL in the subjects with the GG genotype of rs10432782 was compared with the risk of NIHL in the subjects with the TT genotype, OR = 3.17 (95%CI: 1.16 ∼ 6.89). The GT genotype was compared with TT genotype, OR = 2.39 (95%CI: 1.16 ∼ 4.97). In group exposed to 75 ∼ 82 dB CNE (A), the risk of NIHL in the subjects with the GG genotype was compared with the risk of NIHL in the subjects with the TT genotype, OR = 2.35 (95%CI: 0.96 ∼ 5.72), P = 0.06. The GG genotype may bea risk factor of NIHJ.</p><p><b>CONCLUSION</b>The noise exposure level and CNE may influence the relationship between rs2070424, rs10432782 SNPs in SOD1 and noise-induced hearing loss.</p>
Subject(s)
Adult , Female , Humans , Male , Case-Control Studies , Genetic Predisposition to Disease , Genotype , Hearing Loss, Noise-Induced , Genetics , Noise, Occupational , Polymorphism, Single Nucleotide , Superoxide Dismutase , Genetics , Superoxide Dismutase-1 , Surveys and QuestionnairesABSTRACT
<p><b>OBJECTIVE</b>To observe the association between SNPs in SOD1 (rs1041740, rs2070424, rs10432782 and rs4998557) and noise-induced hearing loss in Chinese Han population.</p><p><b>METHODS</b>A case-control study was used to study the effects of environmental risk factors on the susceptibility to noise induced hearing loss (NIHL) in 201 sensitive workers and 202 resistant workers. A questionnaire was designed to carry out an investigation, and an occupational health survey was used to identify the occupational risk factors. Genomic DNA was extracted from peripheral blood cells using standard procedures of Takara kit, and 5 ml blood was from each subject. SNPs were detected using standard procedures of TaqMan probe allele identification method.</p><p><b>RESULTS</b>In SOD1 gene, the A allele of rs2070424 was a protective factor of NIHL, compared with the G allele (OR = 0.67, 95%CI: 0.50 approximately 0.88). The risk with NIHL in subjects with AA genotype was significantly lower than that in subjects with GG genotype (OR = 0.48, 95%CI: 0.26 approximately 0.79). After adjusting the confusion factors, OR was 0.44 and 95%CI was 0.25 approximately 0.78.</p><p><b>CONCLUSION</b>In Chinese Han population, the SNP of rs2070424 in SOD1 may be associated with the susceptibility to NIHL.</p>
Subject(s)
Adolescent , Adult , Female , Humans , Male , Young Adult , Alleles , Asian People , Genetics , Case-Control Studies , Genetic Predisposition to Disease , Genotype , Haplotypes , Hearing Loss, Noise-Induced , Epidemiology , Genetics , Noise, Occupational , Polymorphism, Single Nucleotide , Risk Factors , Superoxide Dismutase , Genetics , Superoxide Dismutase-1ABSTRACT
<p><b>OBJECTIVE</b>To study the adaptive response mechanisms in high background radiation area (HBRA) among Yangjiang local people through gene and protein expression of receptor for advanced glycation end products (RAGE) and S100A6 in peripheral blood and sputum in inhabitants of HBRA.</p><p><b>METHODS</b>A total of 53 male inhabitants were selected from HBRA in Yangjiang as the exposure group, while 53 male inhabitants were selected from Enping (control area, CA)as the control group. The content of RAGE and S100A6 gene and protein were detected by RT-PCR and Western blotting assay. Thermo luminescent dosemeter(TLD) assay was used to measure the outside dose and estimate the effective dose.</p><p><b>RESULTS</b>The effective dose in CA and HBRA was respectively 1.95 mSv and 6.24 mSv, which was 3 fold difference. Compared with CA, RAGE and S100A6 expression were significantly reduced in both gene and protein level in HBRA. The relative median mRNA expression of RAGE and S100A6 in peripheral blood were respectively 0.28, 1.06 and 0.16, 0.79 in CA and HBRA group, there was significance (with analysis Z values of -2.587 and -2.328 respectively, P < 0.05) with Wilcoxon rank test. For the protein of sputum, the relative median expression were respectively 2.98, 2.25 and 0.53, 0.47 with significant difference (with analysis Z values of -2.201 and -2.366 respectively, P < 0.05) by Wilcoxon rank test.</p><p><b>CONCLUSION</b>The low expression of RAGE and S100A6 in HBRA group might be correlated with the adaptive response and the low mortality of cancer in HBRA.</p>
Subject(s)
Humans , Male , Middle Aged , Adaptation, Physiological , Radiation Effects , Background Radiation , Cell Cycle Proteins , Metabolism , China , Receptor for Advanced Glycation End Products , Receptors, Immunologic , Metabolism , S100 Calcium Binding Protein A6 , S100 Proteins , Metabolism , Sickness Impact ProfileABSTRACT
<p><b>OBJECTIVE</b>To study the methylation of O-6-methylguanine-DNA methyltransferase (MGMT) and p16 gene in the sputum cells of radon-exposed population. To provide the experimental base for finding the molecular biomarker of the high risk population of the radon-induced lung cancer.</p><p><b>METHODS</b>91 radon-exposed workers were divided into 4 groups, high dosage group (> 120 WLM), middle dosage group (between 60 and 120 WLM), low dosage group (between 30 and 60 WLB) and lower dosage group (between 2 and 30 WLM) according to the accumulated exposure dosage of the radon daughters. The abnormal methylation of p16 and MGMT gene in the sputum cells of the population in the four groups was detected with the methylation specific PCR (MSP).</p><p><b>RESULTS</b>There was significantly upward trend for the p16 gene methylation rate (0.00%-20.00%), the MGMT gene methylation rate (0.00%-28.00%) and the total methylation rate (0.00%-40.00%) with the increase of the accumulated exposure dosage of the radon daughters (P < 0.01).</p><p><b>CONCLUSION</b>The methylation of p16 and MGMT gene is related to the accumulate exposure dosage of the radon daughters.</p>