Analysis on the characteristics and patterns of work-related musculoskeletal disorders among sonographers in Guangdong Province / 中国职业医学

Objective To analyze the characteristics of work-related musculoskeletal disorders (WMSDs) among sonographers in Guangdong Province, and to explore the disease pattern of the cases. Methods A total of 512 sonographers from 31 hospitals in Guangdong Province were selected as the research subjects using stratified cluster sampling method. The prevalence of WMSDs in the past year was investigated using the Musculoskeletal Disorders Questionnaire, and the characteristics of WMSDs were analyzed. Latent class analysis was used to identify the disease pattern of WMSDs. Results The overall prevalence of WMSDs was 94.3%. The top five affected body parts were right shoulder, neck, right hand/wrist, lower back and right forearm/elbow, with the prevalence of 80.3%, 75.4%, 61.1%, 55.5% and 45.3%, respectively. The prevalence of WMSDs was higher on the right side for the shoulder, hand/wrist, forearm/elbow, hip/leg and knee compared with the left side (80.3% vs 31.3%, 61.1% vs 13.9%, 45.3% vs 10.0%, 17.4% vs 8.6%, 13.1% vs 8.4%, all P<0.05). The prevalence of WMSDs increased with work years, as well the prevalence of WMSDs in the top five affected body parts among the sonographers (all P<0.05). However, there were no statistical differences in prevalence of WMSDs between general hospitals and maternal and child health hospitals, tertiary hospitals and non-tertiary hospitals, Pearl River Delta hospitals and non-Pearl River Delta hospitals; there was also no statistical difference between different genders and age groups of the sonographers (all P>0.05). The best-fit latent disease pattern for sonographers WMSDs comprised three categories： symptom of neck-right shoulder, symptom of neck-lower back-right shoulder-right elbow-right hand/wrist, and symptom of multi-parts above the knees, with the latent probabilities of 0.438, 0.427 and 0.135, respectively. Conclusion The prevalence of WMSDs in sonographers is extremely high, with a dose-effect relationship with work years. The most common affected parts are neck, lower back and right shoulder, right hand/wrist, and right forearm/elbow. The prevalence of WMSDs in the right side of limb was higher than that in the left. WMSDs primarily occur in multiple parts simultaneously. The most common symptoms occur in the neck-right shoulder and neck-lower back-right shoulder-right elbow-right hand/wrist.

Analysis on key aspects of cultural integration for cross-region specialists alliances of closed cooperation / 中华医院管理杂志

Objective:To analyze key aspects in cultural integration for cross-region specialists alliances of closed cooperation, for promoting such integration and identifying efficient operation of the practice.Methods:Quantitative and qualitative methods were used. 192 employees of primary hospitals participated in a questionnaire survey about their personal information and hospital culture self-evaluation on 18th February, 2019. Data so collected were subject to descriptive analysis. On February 21, 2019, the deans of the hospitals were invited for in-depth interviews, and focus group discussions were arranged for 7 doctors from the center hospital who had provided medical support for the primary hospital for more than half and a year, and for 5 doctors and 2 head nurses from the obstetric and neonatal department of the primary hospital respectively. The purpose is to understand the direction, key aspects, achievements and challenges of cultural integration between the two hospitals. Content analysis method was used to study recordings and interview documentation.Results:Employees of the primary hospital had a high satisfaction with indicators of organizational citizenship behavior, and the quality of medical care and team orientation, with the self-rated original scoring for the elements of hospital culture being 3.755, 3.754 and 3.698 respectively. On the other hand, they found insufficiencies in the innovation, poor orientation and incentive mechanism, with the self-rated original scoring for the elements of hospital culture being 3.469, 3.391 and 3.297 respectively. The self-rated total scoring was lower among medical technicians and those with bachelor′s degree or above, which were 3.029 and 3.202 respectively. Hospital culture integration is designed to strengthen technical guidance and care for doctors and patients, and to strengthen cooperation and support in HR training, scientific research innovation and spiritual culture construction. The key to integration is acceptance. The current roadblocks for efficient operation of this model come from medical insurance policy, material resources policy, logistics support, informationization management, personnel training and support and performance management.Conclusions:The cultural integration of cross-region specialists alliances of closed cooperation should be realized through the interactions of values, systems, behaviors and material resources dimensions. Government should play a leading and coordinating role and improve supporting measures.

Analysis on dynamic change of cytokines in patients with occupational trichloroethylene-induced medicamentosa-like dermatitis / 中国职业医学

OBJECTIVE: To analysis the dynamic change of cytokines in patients with occupational trichloroethylene-induced medicamentosa-like dermatitis(OMDT) at the initial stage of treatment. METHODS: Twenty-two cases of early onset OMDT with no glucocorticoid treatment history were selected as the research subjects by judgment sampling method. Blood samples were collected on the 1 st, 2 nd, 3 rd, 4 th and 5 th weeks after admission and on the day of hospital discharge. The levels of tumor necrosis factor-α(TNF-α), interferon-γ(IFN-γ), interleukin(IL)-5, IL-6 and IL-10 in plasma samples were measured by the enzyme linked immunosorbent assay. RESULTS: The five cytokines in patients with exfoliative dermatitis showed an increasing trend at the initial stage of treatment. Among them, the levels of TNF-α, IL-5 and IL-10 reached a peak and then dropped rapidly to form a plateau, and the levels of IFN-γ and IL-6 were slightly increased and the duration of increase was shorter than that of other cytokines. The levels of TNF-α, IFN-γ, IL-5 and IL-6 in patients with erythema multiforme remained within the detection limits in the detection process. Only a few patients showed a short-term increase, the IL-10 level showed a slight increase at the initial stage and then decreased to the plateau stage. The levels of TNF-α, IFN-γ and IL-6 in patients with bullous epidermal necrolysis increased rapidly at the initial detection stage for a short period of time, and then decreased sharply. The level of IL-5 remained at the detection limit, and the IL-10 level showed alternative rising and falling pattern. Part of the dynamic change of cytokines in patients with exfoliative dermatitis and bullous epidermal necrolysis was similar. CONCLUSION: The levels of TNF-α, IFN-γ, IL-5, IL-6, and IL-10 in OMDT patients changed with the progression of the disease at the early treatment stage, and the degree of change was related to the type of rash. Among them, the levels of TNF-α and IL-10 showed dynamic changes due to the progression of the disease, which could be considered as effect biomarkers to evaluate the severity and progression of the disease, and provide a reference for the rational treatment of patients.

Report on the follow-up study of occupational medicamentosa-like dermatitis induced by trichloroethylene / 中国职业医学

OBJECTIVE: To understand the long-term prognosis of patients with occupational medicamentosa-like dermatitis induced by trichloroethylene( OMDT) after recovery. METHODS: A total of 185 patients with OMDT were surveyed through landline and correspondence after recovery. Based on the individual's wishes,19 patients( follow-up examination group)were followed up and arranged for health examination in hospital. RESULTS: Seventy-one cases of OMDT was successfully follow-up. The success rate was 38. 4%( 71/185). Among the 71 cases who were successfully followed up,64. 8%( 46/71)cases complained of physical discomfort. The main complain included skin itching,allergy,upper respiratory tract infection or frequent fever,xerophthalmus,osteonecrosis of femoral head. The 19 cases in the follow-up examination group had different degrees of skin itching,dryness and mild melanosis. The abnormal rates of schirmer I test were 42. 1%( 8/19)and 52. 6%( 10/19) in the left and right eye,respectively. The abnormal rate of tear break-up time in both left and right eyes was 84. 2%( 16/19). The highest positive rate of patch test was chloral hydrate( 100. 0%). There was no abnormality in body temperature,superficial lymph nodes,blood routine,urine routine,liver function and autoimmunity antibody. There was no new rash. CONCLUSION: Different degree of long-term prognosis can occur in OMDT recovery patients. Xerophthalmus and osteonecrosis of femoral head are the major sequelae. Chloral hydrate,which is the main metabolite of trichloroethylene,may be the causative culprit compound for OMDT.

Analyzing the epidemiologic characteristics of occupational medicamentosa-like dermatitis induced by trichloroethylene in Guangdong Province / 中国职业医学

OBJECTIVE: To analyze the epidemiologic characteristics of occupational medicamentosa-like dermatitis induced by trichloroethylene( OMDT) in Guangdong Province. METHODS: The data of OMDT cases diagnosed by Guangdong occupational disease diagnosis institutions from 1988 to 2016 was collected and analyzed. The data of OMDT come from medical records,the National Occupational Disease Network Reporting System and literature retrieval. RESULTS: A total of 475 cases of OMDT were diagnosed in Guangdong Province during 1988 to 2016. The recovery rate was 91. 4%( 434/475),and the fatality rate was 8. 6%( 41/475). All cases had a clear history of trichloroethylene( TCE) exposure and had not been exposed to TCE prior to the present exposure. The median incubation period was 30 days. The exceeding standard rate of TCE time weighted average concentration was 80. 7%( 171/212),and the exceeding standard rate of urine trichloroacetic acid was 75. 0%( 123/164). The years that have most OMDT cases were from 1999 to 2006,which accounted for 64. 0%( 304/475); but there was no seasonal aggregation. The enterprises of OMDT cases concentrated in the Pearl River Delta Region,with Shenzhen City and Dongguan City accounting for 62. 9%. The median age of onset was22 years old,81. 9% of cases were 30 years old or below. The male-female ratio was 1. 2 ∶ 1. 0; 57. 7%( 274/475) cases were from southern China. Meanwhile,95. 4%( 453/475) of the cases came from the manufacturing industry such as electronics factory,hardware factory,electroplating factory and others. CONCLUSION: The distribution of OMDT cases on area,age of onset,native place and occupation in Guangdong Province showed a certain aggregation.

Screening of allergens of trichloroethylene-induced occupational medicamentosa-like dermatitis / 中国职业医学

OBJECTIVE: To screen the allergens of trichloroethylene-induced occupational medicamentosa-like dermatitis( OMDT) by patch test,and explore methods for OMDT auxiliary diagnosis and trichloroethylene( TCE) allergic population screening. METHODS: A total of 20 subjects diagnosed with OMDT were selected as case group,and 22 nonOMDT healthy workers exposed to TCE≥12 weeks were selected as control group. Different concentrations of TCE and its main metabolites such as chloral hydrate( CH),trichloroethanol( TCOH) and trichloroacetic acid( TCA) were used as allergens in a skin patch test in workers of these two groups. Another 20 new workers exposed to TCE < 12 weeks without OMDT were tested as validation group. They were tested with a patch test at a mass fraction of 15. 00% CH and follow-up observations were performed until 12 weeks of TCE exposure. RESULTS: The patch test of TCE,CH,TCOH and TCA were negative in the control group. In the case group,the patch test positive rate for 50. 00% TCE was 10. 00%,the patch tests were negative in 25. 00%,10. 00% and 5. 00% TCE. The CH patch test positive rate was 100. 00% with the CH mass concentrations of 15. 00%,10. 00% and 5. 00%. The TCOH patch test positive rates were 90. 00%,75. 00% and50. 00%,with the corresponding concentration of 5. 00%,0. 50% and 0. 05%. The TCA patch test positive rates were50. 00% and 0. 00% with the TCA concentrations of 5. 00% and 0. 50% respectively. When the mass concentration was5. 00%,the patch test positive rates in case group from high to low were CH,TCOH,TCA and TCE( P < 0. 01). And the patch test positive rates of CH and TCOH showed no statistical significant difference( P > 0. 05). The patch test positive rate of TCOH increased with increase of TCOH mass concentrations( P < 0. 01). The patch test positive rates for 5. 00%TCA was higher than that of 0. 50% TCA( P < 0. 01). The patch test positive rate in 0. 50% TCOH was higher than that of 0. 50% TCA( P < 0. 01). In the validation group,the patch test of 15. 00% CH was negative,and there was no OMDT case found during the follow-up 12 weeks of TCE exposure. CONCLUSION: The metabolites CH and TCOH of TCE may be the main allergens of OMDT after exposure to TCE. The CH and TCOH patch test can be an auxiliary diagnosis method for OMDT. The CH patch test could be used as a method for screening population allergic to TCE.

Comparison and application of two risk assessment methods for occupational lead exposure risk classification in a lead-acid battery enterprise / 中华劳动卫生职业病杂志

Objective@#To apply and compare two risk assessment methods for occupational lead exposure risk classification in a lead-acid battery enterprise.@*Methods@#In April 2013, an occupational health survey was carried out in a lead-acid battery enterprise. Lead smoke and lead dust were tested in the workplace. The risk assessment index system for occupational chemical hazards that was established and optimized by the research group (referred to as "optimized index system" ) , as well as the Singapore semi-quantitative risk assessment model, was used for occupational lead exposure risk classification in the lead-acid battery enterprise. The two risk classification results were analyzed and compared.@*Results@#In the lead smoke risk classification results, the optimized index system classified the raw material group and foundry group workshops as Class I hazardous and the assembling group workshop as Class II hazardous. The Singapore semi-quantitative risk assessment model classified the raw material group workshop as high risk and foundry group and assembling group workshops as extremely high risk. In the lead dust risk classification results, the optimized index system classified the raw material group workshop as Class I hazardous, while the plate painting group, plate cutting group, and assembling group workshops were classified as Class II hazardous. The Singapore semi-quantitative risk assessment model classified the raw material group workshop as medium risk, the plate painting group and plate cutting group workshops as high risk, and the assembling group workshop as extremely high risk.@*Conclusion@#There are some differences in risk assessment of occupational lead exposure between the two risk assessment methods. The optimized index system is comparably more reasonable and feasible, and is highly operable.

Characteristic changes of finger skin temperature in cold provocation test in workers with vibration white finger / 中国职业医学

OBJECTIVE: To analyze the changes of finger skin temperature in cold provocation test( CPT) in workers with vibration white finger( VWF). METHODS: A total of 245 male workers engaged in hand arm vibration operation was selected as study subjects using random number table method. All subjects were divided into VWF group( 73 persons) and control group( 172 persons). CPT( 10 ℃,10 min) was performed and the skin temperature of 6 fingers( index finger,middle finger and ring finger of both hands) was measured at pre-CPT adaptation period( 0,10,20,30 min) and after CPT period( 0,5,10,15,20,25,30 min). RESULTS: The effect of interaction between grouping and observe time was statistically significant on finger skin temperature( P < 0. 01). In the pre-CPT adaptation period,there was no statistically significant difference on skin temperature between 10 and 30 min time point in the two groups( P > 0. 05). After CPT,the fingers skin temperature of VWF group was lower than that of control group at 5 min time point( P < 0. 05),but there were no statistically significant differences on fingers skin temperature of other time points between the two groups( P > 0. 05).In both groups,the finger skin temperature at 0 min time point after CPT were lower than other time points in the same group( P < 0. 05),and the finger skin temperature increased with time( P < 0. 01). However,the finger skin temperature at 30 min after CPT did not restore to that at 30 min time point of pre-CPT. Except the VWF group,the abnormal rewarming temperature at 5 min time point after CPT of left index finger,the right index finger and the right ring finger were higher than that of the control group( 72. 6% vs 56. 4%,75. 3% vs 57. 6%,86. 3% vs 65. 1%,P < 0. 05),but there were no statistically significant differences on the abnormal rewarming temperature at 10,30 min time points of the six fingers in the two groups( P > 0. 05). There were no statistically significant differences on the detection rate of abnormal rewarming temperature between left index finger and the right index finger,or the right index finger and the right ring finger in the VWF group( 72. 6% vs 75. 3%,75. 3% vs 86. 3%,P > 0. 05). CONCLUSION: When CPT( 10 ℃,10 min) was performed in workers engaged in hand arm vibration operation,it is recommended to measure the finger skin temperature of index finger,and adaptation time before CPT can be adjusted to 10 min.

Clinical pathway on occupational medicamentosa-like dermatitis due to trichloroethylene / 中国职业医学

OBJECTIVE: To establish the clinical pathway of occupational medicamentosa-like dermatitis due to trichloroethylene(OMDT).METHODS: OMDT was selected as the clinical disease category.The diagnosis and treatment schemes of OMDT were determined and the clinical pathway was developed on the basis of evidence-based medicine,clinical data analysis,and the expert opinion as well as GBZ 185—2006 Diagnostic Criteria of Occupational Medicamentosa-like Dermatitis due to Trichloroethylene.The initial clinical validation was performed.RESULTS: We formulated the clinical pathway of OMDT for medical staffs,including standard hospitalization procedures(including normative use of glucocorticoids),Clinical Path Form,and Informed Consent for Glucocorticoid Therapy.The Clinical Pathway Notification of OMDT for patients or their family members was established.Based on the initial clinical verifications,the clinical pathway was conducive to optimize the medical process,none of the patients suffered from rebounds and complications,and the awareness of OMDT and satisfaction with treatments were improved.CONCLUSION: The clinical pathway for OMDT is scientific and reasonable,which is suitable for use to regulate medical behaviors.

The effect of occupational and environmental factors on the pregnancy for Down's syndrome / 中国职业医学

OBJECTIVE: To investigate the influence of occupational and environmental factors on the pregnancy for Down's syndrome. METHODS: By systematic sampling method,97 pregnant women who had been diagnosed as Down's syndrome by Giemsa staining on fetal chromosomes in chorionic villus sampling,amniocentesis,or umbilical cord blood sampling were selected as the case group,while 373 non-Down's syndrome pregnant women after same examinations during the same period in the same hospital were selected as the control group. The history of exposure before pregnancy to occupational and environmental factors was analyzed. RESULTS: The pregnant women aged over 35 years had higher risk of Down's syndrome than those aged under 35 years( P < 0. 01). The pregnant women with occupational exposure to organic solvents containing benzene had higher risk of Down's syndrome than those without occupational exposure history to hazardous substances( P < 0. 01). The pregnant women using estrogenic drugs before pregnancy or during early pregnancy had higher risk of Down's syndrome than those without drug use( P < 0. 05). The pregnant women living in newly-decorated houses or using the new furniture had higher risk of Down's syndrome than those without new decoration( P < 0. 01). The pregnant women with pre-pregnancy intake of folic acid had lower risk of Down's syndrome than those without any intake of folic acid supplement( P < 0. 05). CONCLUSION: The age,occupational exposure to benzene solvents and taking estrogenic drugs were the major leading factors of development of Down's syndrome.

Observation and measurement of silicosis animal model by PET-CT / 中国职业医学

OBJECTIVE: To explore the feasibility of dynamic observation and measurement of living silicosis rat model by using small animal positron emission tomography( PET)-computed tomography( CT). METHODS: Specific pathogens free SD rats were divided into model group and control group. The silicosis rat model was established by one-time endotracheal injection of 30 g/L silica suspension,while the control group rats were injected of isopyknic 0. 9% sodium chloride solution. Six rats from each group were randomly selected for CT scan from 1st,2nd,3rd,4th,6th,8th and 12 th week after silica injection using the small animal PET-CT. CT value and standardized uptake value( SUV) of18F-fluorodeoxyglucose were measured. Lung tissue was collected for pathological sections. The levels of hydroxyproline( HYP) of lung tissue and serum transforming growth factor β1( TGF-β1) and interleukin-1( IL-1) were measured.RESULTS: Pathological sections of rats of model group showed inflammatory exudation,inflammation reduced and fibrosis increased with extended time. The results are identical with findings in PET-CT. Lung SUV of rats in model group in the1st-3rd weeks were higher than that in control group in the same time point( P < 0. 05) and decreased by the increasing time during the 1st-4 th weeks of dust injection( P < 0. 05). Lung CT values of model group in the 1st-12 th weeks were higher than that of control group in the same 7 time points( P < 0. 05) and decreased in the 1st-6th weeks and then increased in the 6th-12th weeks by the increasing time of dust injection( P < 0. 05). Lung coefficients and HYP levels of model group in the 7 time points were higher than that of control group in the same 7 time points( P < 0. 05). Lung coefficients decreased in 1st-4th weeks and lung HYP levels increased in 6th-12th weeks with the increasing time of dust injection( P < 0. 05). Excepted of the 3rd and 4th weeks,serum TGF-β1 levels of model group in other 5 time-points were higher than that of control group in the same 5 time points( P < 0. 05) and decreased in the 1st-4th weeks( P < 0. 05)then increased in the 4th-8th weeks( P < 0. 05) by the increasing time of dust injection. Serum IL-1 levels of model group in the 1st-4th weeks were higher than that of control group in the same 4 time points( P < 0. 05) and decreased by the increasing time of dust injection( P < 0. 05) and decreased by the increasing time of dust injection( P < 0. 05).CONCLUSION: Early inflammation and terminal fibrosis of living silicosis rat model could be observed effectively by small animal PET-CT,which can be used as a new approach for dynamic tracing silicosis in rat models.

Survey of gynecological diseases on female workers in an automobile manufacturing company / 中国职业医学

OBJECTIVE: To analyze the current prevalence status of gynecological diseases on female workers in an automobile manufacturing company. METHODS: By judgment sampling,382 female workers who exposed to occupational hazard factors were selected as exposure group and 367 female executive staffs without exposure to those factors were selected as control group. Among the three subgroups of the exposure group,the prevalence rate of vaginitis,pelvic inflammatory disease,cervicitis,annex cysts,ovarian cysts and uterine fibroid in these two groups were analyzed. RESULTS: The prevalence rate of vaginitis and uterine fibroid in exposure group was higher than that of control group(24. 9% vs20. 7%,20. 4% vs 9. 8%,P < 0. 05). Among the three subgroups of the exposure group,the prevalence rate of vaginitis in welding subgroup was the highest(35. 4%,P < 0. 017); the prevalence rate of annex cysts in coating subgroup was the highest among all subgroups(11. 4%,P < 0. 017); the prevalence rate of uterine fibroid in assembly subgroup was the highest(28. 1%,P < 0. 017). The prevalence rate of uterine fibroid in exposure group presented an increasing tendency with the increase of age(P < 0. 05). The prevalence rate of cervicitis,annex cysts and uterine fibroid in exposure group presented an increasing tendency with the increase of seniority(P < 0. 05). CONCLUSION: The prevalence rate of gynecological diseases in female workers who exposed to occupational hazard factors in an automobile manufacturing company was significantly higher than general population. The prevalence rate of gynecological diseases among different types of female workers was significantly different. Disparity of gynecological diseases prevalence of female workers might due to differences in occupational hazard factors exposure.

Intervening effect of bone marrow-derived mesenchymal stem cells for silica-induced pulmonary fibrosis in rats / 中国职业医学

OBJECTIVE: To explore the intervening effects of bone marrow-derived mesenchymal stem cells(BMMSCs) for pulmonary fibrosis of rats exposed to silica dust at different stages. METHODS: Specific pathogen free SD rats were randomly divided into model group,2-week group,4-week group and control group with 6 rats in each group(half males and half females). Rats of the first three groups were one-time endotracheally injected with 0. 5 mL aseptic silica suspension at 30 g/L mass concentration. Rats of control group were injected with 0. 5 mL 0. 90% sodium chloride solution. Rats of 2-week group and 4-week group were injected with 0. 5 mL BMMSCs suspension with cell density was 5 × 10~9/L at 2 weeks and 4 weeks respectively after silica dust exposure,while model group and control group were injected with aseptic 0. 90% sodium chloride solution in the same volume. After that all rats were examined by lung computed tomography(CT) scan,pathological sections were observed,lung coefficient were measured,lung tissue hydroxyproline(HYP) content and serum transforming growth factor β1(TGF-β1) concentration were investigated at the 12 th week after silica dust exposure. RESULTS: Lung CT image showed clean lung field and clear pulmonary parenchyma in control group.Multiple and diffused high density granular shadows of different size and streak/reticular fiber shadows in model group;diffused distribution of very small granular shadows in 2-week group; granular shadows and local reticular fiber shadows in 4-week group,and either the size or the area of granular shadows was smaller than model group. The lung CT value,lung coefficient,lung tissue HYP content and serum TGF-β1 concentration of model group,2-week group and 4-week group were higher than those of control group(P < 0. 05). The lung CT value,lung tissue HYP content and serum TGF-β1 concentration of control group,2-week group,4-week group and model group were elevated in turn(P < 0. 05),while the lung coefficient of model group and 4-week group was higher than that of 2-week group respectively(P < 0. 05).CONCLUSION: BMMSCs could delay pulmonary fibrosis caused by silica dust,and the protective effect is better at early stage than later stage of fibrosis.

Comparison of risk rating for chemical hazards in a petrochemical enterprise with two risk assessment methods / 中国职业医学

OBJECTIVE: To compare and analyze the risk rating for chemical hazards of aromatics complex in a petrochemical enterprise using two risk assessment methods. METHODS: Occupational hygiene investigation and chemical detection for workplaces of the construction project were made. The risk ratings were made in five workplaces including that of the aromatics extraction,disproportionation,isomerization,xylene fractionation and adsorptive fractionation. Two risk assessment methods were employed. They were the optimal indicator system of risk assessment on occupational chemical hazards( optimal indicator system) and the semi quantitative risk assessment model of Singapore. The results of risk rating generated by the two risk assessment methods were then compared and analyzed. RESULTS: Using the optimal indicator system,the risk rating of benzene was mild in the five workplaces; and the risk rating of methylbenzene and xylene was slight. However,using the semi quantitative risk assessment model of Singapore,the risk rating of benzene was extremely high in both the aromatics extraction and disproportionation workplaces; the risk rating was high in xylene fractionation,and was medium in the isomerization and adsorptive fractionation workplaces. The risk rating of methylbenzene was high in the aromatics extraction and disproportionation workplaces,and was low in the other three workplaces. The risk rating of xylene was low in the five workplaces. CONCLUSION: The optimal indicator system is more feasible,practical and objective for the assessment of chemical hazards. It is more suitable for risk assessment of occupational chemical hazards in our country.

Distribution of copper and zinc level in urine of general population in eight provinces of China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To describe the distribution of zinc (Zn) and copper (Cu) in urine samples of generalpopulation in eight provinces of China, to analyze their characteristics of distribution between different region, gender and age-cohorts, and to provide the baseline of themetabolites in the general population.</p><p><b>METHODS</b>From 2009 to 2010, 18 120 subjects from the general population aged from 6 to 60 years old were recruited from 24 areas among 8 provinces of China mainland by random sampling. The environmental and physical condition characteristics were collected from questionnaires, and urine samples were collected at the mean time. The levels of Zn and Cu in urine were measured using ICP-MS. Data were analyzed by statistical methods to compare the distribution characteristics of Zn and Cu among populations with different ages and genders.</p><p><b>RESULTS</b>Totally, the median of Cu and Zn in urine were 9.28 and 115.47 µg/L respectively; and the inter-quartile range of Cu and Zn were 2.66-16.09 and 35.32-265.15 µg/L respectively. The median of Cu in male and female were 9.90 and 8.60 µg/L (Z=-5.63, P<0.001), and Zn in male and female were 140.44 and 95.27 µg/L (Z=-14.79, P<0.001). The median of Cu among the groups aged 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were 9.30, 10.14, 9.67, 9.33, 8.38 and 8.74 µg/L (χ2=70.94, P<0.001), respectively, and the median of Zn 130.83, 132.07, 139.34, 109.3, 78.74 and 109.51 µg/L ((χ2=146.00, P<0.001), respectively.There was statistically significant differences in urinary Cu and Zn levels between male and female, and among the different age groups.</p><p><b>CONCLUSION</b>The Cu and Zn levels and distribution in urine among general population between 2009 and 2010 in China were reported in this article. These basic data in China will provide scientific and reliable reference for further scientific research.</p>

Study of distribution and influencing factors of lead and cadmium in whole blood and urine among population in 8 provinces in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the levels of lead (Pb) and cadmium (Cd) in blood and urine among general population in China, and thereby analyze their prevalent features.</p><p><b>METHODS</b>A total of 18 120 subjects from general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland from 2009 to 2010, by cluster random sampling method. The blood samples and urine samples of these people were collected. The questionnaire survey was used to collect the information of the living environment and health conditions.Inductive coupled plasma mass spectrometry was applied to test the Pb and Cd levels in the samples, and the distribution of Pb and Cd in blood and urine for different ages, genders, areas and life habits were then analyzed.</p><p><b>RESULTS</b>Among the general population in China, the geometric mean (GM) of blood Pb concentration was 34.9 µg/L; the GM of blood Pb in male and female groups were 40.1 and 30.4 µg/L (Z = -28.05, P < 0.05), respectively; the GM from eastern, central and western China were 31.2, 38.8 and 58.9 µg/L (χ(2) = 1 483.33, P < 0.05) , respectively. The GM of urine Pb of the whole population was 1.05 µg/L;while the GM in male and female groups were 1.06 µg/L and 1.05 µg/L (Z = -0.73, P > 0.05) , respectively;the values from eastern, central and western China were 0.76, 2.85 and 3.22 µg/L (χ(2) = 1 982.11, P < 0.05), respectively. The GM of blood Cd concentration among general population was 0.49 µg/L; and the values in male and female group were 0.60 and 0.41 µg/L (Z = -11.79, P < 0.05) , respectively; the GM from eastern, central and western China were 0.45, 0.65 and 0.67 µg/L (χ(2) = 69.87, P < 0.05), respectively; the GM of urine Cd concentration of the whole population was 0.28 µg/L, while the GM in male and female groups were 0.29 and 0.28 µg/L (Z = -3.86, P < 0.05), respectively; the values from eastern, central and western China were 0.29,0.42 and 0.18 µg/L (χ(2) = 402.76, P < 0.05), respectively. the Spearman's rank correlation coefficient for Cd in blood and Cd in urine was 0.22, for Pb in blood and Pb in urine was 0.21. Both the correlations were statistic significant (P < 0.05).</p><p><b>CONCLUSION</b>The Pb and Cd levels in blood and urine were relatively higher among general population in China varying by gender and area. There were positive correlations between Pb and Cd levels in blood and those in urine.</p>

Study of distribution and influencing factors of arsenic in whole blood and urine among population in 8 provinces in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluated the levels of arsenic (As) in blood and urine among general population in China and analyze its influencing factors.</p><p><b>METHODS</b>A total of 18 120 subjects from general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland from 2009 to 2010, by cluster random sampling method. Blood samples and urine samples were collected, the information of the life-style was collected by questionnaire.Inductive coupled plasma mass spectrometry was applied to test the As level in the samples, and the distribution of As in blood and urine for different ages, genders, areas and life habits were then analyzed.</p><p><b>RESULTS</b>The geometric mean (GM) of blood As concentration among general population was 2.33 µg/L;the GM of blood As in male (2.35 µg/L) was higher than and female (2.30 µg/L) (Z = -1.42, P < 0.05); from eastern, central to western China, the blood As level were 2.94, 1.30 and 0.98 µg/L (χ(2) = 643.22, P < 0.05) , respectively; the GM in smokers (2.84 µg/L) was higher than non-smokers (2.27) (Z = -6.28, P < 0.05) ;the seafood consumer had a higher blood As level (2.59 µg/L) than people not consuming seafood (1.47 µg/L) (Z = -23.68, P < 0.05). The urine As level of the whole population was 13.72 µg/L;while its GM in male (14.10 µg/L) was higher than female (13.33 µg/L) (Z = -3.94, P < 0.05); the values from eastern, central to western China were 14.14, 16.02 and 9.57 µg/L (χ(2) = 353.89, P < 0.05), respectively;the level in smokers (16.06 µg/L) was higher than nonsmokers (13.70 µg/L) (Z = -2.63, P < 0.05); the level in seafood consumers (14.82 µg/L) was higher than people not consuming seafood (10.99 µg/L) (Z = -3.20, P < 0.05). The blood As level had a positive correlation with urine As level (correlation coefficient:0.285, P < 0.05).</p><p><b>CONCLUSION</b>The As level in blood and urine varied by gender and area among general population in China, and related to life-styles. There was a positive correlation between As level in blood and that in urine.</p>

Polycyclic aromatic hydrocarbons monohydroxy metabolites level in urine of general population in eight provinces of China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To assess the levels of polycyclic aromatic hydrocarbons monohydroxy metabolites in urine of general population in China among 8 provinces, provide the baseline of the metabolites in the general population.</p><p><b>METHODS</b>From 2009 to 2010, 18 120 subjects of general population aged 6-60 years old were recruited from 24 areas among 8 provinces in east, west and central areas of China mainland by cluster random sampling. The information of the living environment and health condition were collected by questionnaire and spot urine samples were collected, 4 680 urine samples were analysed by high performance liquid chromatography with tandem mass spectrometry, and monohydroxy metabolites distribution in urine among groups of gender and ages were analysed.</p><p><b>RESULTS</b>Geometric means (GM) of 2-naphthol, 1-naphthol, 3-phenanthrol and 1-hydroxypyrene concentration in urine (95%CI) were 1.85 (1.75-1.95), 1.55 (1.50-1.61), 0.57 (0.54-0.59) and 0.82 (0.78-0.85) µg/L, respectively;and median are 2.44, <0.50, 0.72 and 0.90 µg/L, respectively. The concentration between male and female were significantly different (P < 0.01), and the concentration among the groups of population were significantly different (P < 0.01), the GM of 2-naphthol among the groups of population aged 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were 1.60, 1.56, 1.69, 2.23, 1.91 and 1.86 µg/L (χ(2) = 17.90, P < 0.01), the GM of 1-naphthol in the groups were 1.30, 1.16, 1.53, 1.68, 1.80 and 1.52 µg/L (χ(2) = 76.22, P < 0.01), the GM of 3-phenanthrol in the groups were 0.78, 0.76, 0.55, 0.42, 0.50 and 0.99 µg/L (χ(2) = 66.48, P < 0.01), the GM of 1-hydroxypyrene in the groups were 0.77,0.64, 1.00, 0.84, 0.84 and 0.57 µg/L (χ(2) = 51.48, P < 0.01), respectively.</p><p><b>CONCLUSION</b>The distribution of monohydroxy metabolites levels in urine of general population were different, it provided a basic data for the further study of polycyclic aromatic hydrocarbons biomonitoring in the population.</p>

Distribution of copper and zinc in blood among general population from 8 provinces in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the level of zinc (Zn) and copper (Cu) in whole blood among general population from 8 provinces in China, and to analyze the characteristics of distribution among different regions.</p><p><b>METHODS</b>This cross-sectional study was performed in 8 provinces from eastern, middle and western China between 2009 and 2010, including 13 110 subjects from 24 regions, and the blood and urine samples were collected. The ICP-MS was applied to test the content of ICP-MS in blood samples, and the results were used to analyze the characteristics of contents and distributions of Zn and Cu among population from different ages, genders and regions groups.</p><p><b>RESULTS</b>Totally, the mean (95%CI) contents of Cu and Zn in blood were 795 (791-799)µg/L and 3 996(3 976-4 015) µg/L, respectively. The characteristics of distribution of Cu content were as followed, the content of males were lower than it of females (male:767 µg/L; female: 822 µg/L, t = -13.302, P < 0.01). The contents of blood Cu in groups of people aging 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were separately 860(853-868), 758(748-769), 734(728-734), 782(774-790), 811(795-827) and 820(815-826) µg/L. The differences showed statistical significance (F = 78.77, P < 0.01). The blood Cu content of people in eastern China (800µg/L) were also significantly higher than it in middle (774 µg/L)and western China (782 µg/L) (F = 10.94, P < 0.01). Distribution of blood Zn content showed characteristics as follows: the Zn content was higher in males than in females (male 4 085 µg/L and female 3 908 µg/L, t = 8.78, P < 0.01). The contents of blood Zn in groups of people aging 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were separately 3 306 (3 261-3 350), 3 888 (3 839-3 937), 3 948 (3 902-3 994), 4 272(4 228-4 315), 4 231(4 180-4 281) and 4 250 (4 205-4 294)µg/L, which showed significant statistical differences (F = 233.68, P < 0.01). The blood Zn content of people in eastern China (3 938 µg/L) were significantly lower than it in middle (4 237 µg/L)and western China (4 105 µg/L) (F = 53.16, P < 0.01). In addition, the study also compared the relation between content of Cu and Zn and the frequency of eating seafood. The results found that the frequency of eating seafood could influence the content of Cu and Zn (Cu: F = 13.54, P < 0.01; Zn: F = 200.20, P < 0.01).</p><p><b>CONCLUSION</b>The contents and distributions of Cu and Zn in blood differs among people from different groups in ages, genders and regions. The baseline data of this study provided reliable scientific evidence for further research.</p>

Distribution of manganese, cobalt and molybdenum in blood and urine among general population in 8 provinces of China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluated the manganese (Mn), cobalt (Co) and molybdenum (Mo) levels in blood and urine among general population in China, and thereby to analyze their prevalent features.</p><p><b>METHODS</b>From 2009 to 2010, a total of 18 120 subjects of general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland, by cluster random sampling method. The information about their living environment and health status were collected by questionnaire, and their blood and urine samples were also collected.Inductive coupled plasma mass spectrometry (ICP-MS) was applied to test the Mn, Co and Mo levels of blood and urine samples, and the Mn, Co, Mo distribution in blood and urine among groups of population in different ages and genders were then analyzed.</p><p><b>RESULTS</b>Among general population in China, the geometric mean (GM) of Mn concentration in blood was 8.98 µg/L. The Mn concentration in blood among males and females were separately 8.14 µg/L and 9.88 µg/L (Z = -18.84, P < 0.01). The GM of Mn concentration in urine was 0.63 µg/L. The Mn concentration in urine among males and females were separately 0.62 µg/L and 0.63 µg/L (Z = -0.67, P > 0.05). The geometric mean (GM) of Co concentration in blood was 0.194 µg/L. The Co concentration in blood among males and females were separately 0.166 µg/L and 0.225 µg/L (Z = -23.04, P < 0.01). The GM of Co concentration in urine was 0.282 µg/L. The Co concentration in urine among males and females were separately 0.260 µg/L and 0.307 µg/L (Z = -7.35, P < 0.01). The GM of Mo concentration in blood was 0.25 µg/L. The Mo concentration in blood among male and female group were separately 0.27 µg/L and 0.23 µg/L (Z = -5.03, P < 0.01). The GM of Mo concentration in urine was 27.7 µg/L. The Mo concentration in urine among males and females were 29.8 µg/L and 25.6 µg/L (Z = -6.31, P < 0.01), respectively.</p><p><b>CONCLUSION</b>The Mn, Co and Mo levels in blood and urine varied by gender and area among general population in China, the study provided basic data evidence for the following Mn, Co and Mo biological monitoring studies in near future.</p>