Objective: To analyze the incidence characteristics of occupational diseases in Guangzhou from 2010 to 2020, provide scientific basis for formulating occupational disease prevention and control policies. Methods: In January 2021, based on the data of occupational diseases in Guangzhou reported in the Information Monitoring System of Occupational Diseases and Occupational Health, descriptive epidemiological method was used to analyze the types and characteristics of occupational diseases in Guangzhou from 2010 to 2020. Results: A total of 1341 cases of 38 kinds of occupational diseases in 9 categories were reported in the past 11 years. The incidence of occupational pneumoconiosis, occupational otolaryngology and oral diseases and occupational chemical poisoning ranked the top three, accounting for 38.1% (511/1341) , 30.5% (409/1341) and 16.2% (217/1341) of the total cases respectively. The cases of pneumoconiosis in welders and silicosis accounted for 47.7% (244/511) and 34.4% (176/511) of the cases of occupational pneumoconiosis respectively. The cases of noise deafness accounted for 99.8% (408/409) of occupational otorhinolaryngology oral diseases. Acute occupational chemical poisoning cases accounted for 26.7% (58/217) of the occupational chemical poisoning cases, in which dichloroethane poisoning cases ranked the first, accounting for 79.3% (46/58) . Chronic occupational chemical poisoning cases accounted for 73.3% (159/217) of the occupational poisoning cases, in which benzene and lead poisoning cases ranked the top two, accounting for 79.2% (126/159) and 17.6% (28/159) respectively. Conclusion: Pneumoconiosis, silicosis, noise deafness, benzene poisoning, lead poisoning, dichloroethane poisoning should be supervised and managed as key occupational diseases in Guangzhou.
Benzene ; China/epidemiology* ; Deafness ; Ethylene Dichlorides ; Humans ; Incidence ; Lead Poisoning ; Occupational Diseases/epidemiology* ; Pneumoconiosis/epidemiology* ; Silicosis

Ethylene Dichlorides ; Humans ; Poisoning

OBJECTIVETo investigate the feasibility of using the concentration of 1,2-DCE in blood as a biological monitoring indicators and build the determination method of 1,2-DCE in blood.

METHODSDose-response relationship of the exposure of 1,2-DCE and the level of 1,2-DCE in rat blood were investigated using the Pearson's correlation analysis. The concentration of 1,2-DCE in blood was determined using Headspace Sampler-Gas Chromatography-Mass Spectrometer (HS-GC-MS). 3.0 ml blood sample diluting with 2.0 ml 1,2-DCE standard serial solution was placed in 15 headspace bottles respectively and heated at 80 ℃ for 20 min.The vapor upon the headspace bottle was separated by capillary column and the concentration of 1,2-DCE was determined by massspectrum in SIM mode to draw a standard work curve. The within-run precision and the between-run precision were calculated by the relative standard deviation (RSD) of the concentration of 1,2-DCE in blood which was determined 6 times in a day and 6 times within 3 days respectively. The recovery rate was calculated by P=(C2 -C0)/C1 × 100%.

RESULTSWhen the treatment groups were exposed at dosage of 1,472, 2,550, 3,093, 3,976, and 4 418 mg/m(3), the average concentration of 1,2-DCE in rat blood was 24.1,231.6,344.3,395.1,538.5 μg/L. There was a positive correlation between the concentration of 1,2-DCE in rat blood and the exposed level of 1,2-DCE.The equation of dose-response relationship was y=0.162x -195.8,r=0.982 2,P=0.003 and the precision of exposure experiments was 7.04% -13.15%. 1,2-DCE contents within 0.259 -2 587 μg/L showed a good linear relationship and the regression equation was y=47 901x -357 446, r= 0.999 8. When the blood containing 0.259 μg/L 1,2-DCE was determined for six times, the average peak/peak signal-to-noise ratio was 56.55. The limit of detection (LOD) was 0.014 μg/L and the limit of quantification (LOQ) was 0.046 μg/L. The within-run precision was 1.23% -2.76% and the between-run precision was 2.21% -4.64%. The average recovery rate was 93.3% - 98.6%.

CONCLUSIONThe concentration of 1,2-DCE in blood could be used as a biological monitoring indicator. The method of the concentration of 1,2-DCE in blood determining by HS-GC-MS was characterized by high sensitivity, wide linear range, small interference, high precision and easy operation.

Animals ; Environmental Exposure ; analysis ; Environmental Monitoring ; Ethylene Dichlorides ; blood ; Gas Chromatography-Mass Spectrometry ; Limit of Detection ; Rats

Ethylene Dichlorides ; poisoning ; Humans ; Intracranial Pressure ; drug effects ; Occupational Exposure ; adverse effects

OBJECTIVETo observe the clinical characteristics and regular patterns of subacute 1, 2-dichloroethane poisoning patients for providing evidences to it's diagnosis, treatment and prognosis.

METHODS51 cases of subacute 1, 2-dichloroethane poisoning analyzed. They were divided into 3 groups according to their main clinical manifestation: group A mainly with intracranial hypertension (n = 25), group B with limbs tremor (n = 18), group C with mental and behavior disorder (n = 8). All cases' clinical symptoms, cranial computer tomography, cerebrospinal pressure (Group A) were observed, the durations of the onset, deterioration, improvement, recovery and whole course of the disease were compared between groups and in each group.

RESULTSIn all of 51 cases, only the differences between the deterioration duration of cranial CT and symptom was significantly (t = 2.555, P<0.05), which indicate the deterioration of symptom was earlier than radiological change. The symptom deterioration of group C was the fastest than group A and group B (P<0.00). As to the change of symptom duration, group B's improvement, recovery and whole course was the longest comparing with group A and group C (P<0.05). As to the change of cranial CT duration, group B's recovery duration was the shortest and group A's recovery duration was the longest (P<0.01); group B's whole course was also the shortest and group A's whole course was the longest (P<0.05). The clinical course of symptoms, cranial computer tomography, cerebrospinal pressure (Group A) was compared in each group, in group A, the duration of improvement and whole course of the cranial CT and cerebrospinal pressure change was longer than that of the symptom change (P<0.01), this indicated that group A has longer asymptomatic intracranial hypertension and their cranial radiography recover slowly. In group B, their symptoms (3.94 ± 4.31 days) deteriorated is earlier than cranial CT changes (P<0.05), the recovery (92.39 ± 55.04 days) and whole course of symptom was longer than cranial CT change (all P<0.01). In group C, symptom deterioration was earlier than CT deterioration (P< 0.05).

CONCLUSIONThe clinical characteristic of subacute 1, 2- dichloroethane poisoning is central nervous system damage, it differs according to the different stage of course, the regions and severity of pathology lesions.

Cerebrospinal Fluid Pressure ; Disease Progression ; Ethylene Dichlorides ; poisoning ; Humans ; Intracranial Hypertension ; Mental Disorders ; Poisoning ; diagnosis ; pathology ; Prognosis ; Tomography, X-Ray Computed ; Tremor

Acupuncture Therapy ; Adult ; Ethylene Dichlorides ; toxicity ; Humans ; Male ; Neurotoxicity Syndromes ; etiology ; therapy

Acute Disease ; Adolescent ; Adult ; Ethylene Dichlorides ; poisoning ; Female ; Humans ; Male ; Middle Aged ; Neurotoxicity Syndromes ; diagnostic imaging ; etiology ; Tomography, Spiral Computed ; methods ; Young Adult

OBJECTIVETo establish a rat model of 1,2-dichloroethane (DCE)-induced subacute toxic encephalopathy.

METHODSSixty Sprague-Dawley rats were randomly divided into five groups: negative control, positive control, low-dose DCE (1 472 mg/m(3)), middle-dose DCE (2 550 mg/m(3)), and high-dose DCE (4 418 mg/m(3)). The three DCE groups received static inhalation of DCE 6 hours a day for 6 consecutive days. The positive control group received intraperitoneal injection of lipopolysaccharide (5 mg/kg) and were sacrificed 8 hours after injection. Blood and brain tissue were collected, followed by determination of brain water content and HE staining for pathological examination of brain tissue.

RESULTSThe rats in DCE groups suffered decreased body weight with increasing DCE dose (P < 0.01), and brain water content rose with increasing DCEdose. The brain water content of middle-dose DCE group (80.09 ± 0.14%) and high-dose DCE group (80.28±0.10%) increased significantly as compared with that of the negative control group (79.46±0.23%) (P < 0.001). Optical microscopy discovered loose structure and vasodilation in the brain tissue of middle-dose DCE group, indicating obvious brain edema; the high-dose DCE group and positive control group had spongiform and vacuolated brain tissues with severe vascular dilation, indicating severe brain edema.

CONCLUSIONA rat model of subacute toxic encephalopathy induced by 1, 2-dichloroethane has been successfully established.

Animals ; Disease Models, Animal ; Ethylene Dichlorides ; toxicity ; Male ; Neurotoxicity Syndromes ; Rats ; Rats, Sprague-Dawley

Acute Disease ; Adolescent ; Adult ; Drugs, Chinese Herbal ; therapeutic use ; Ethylene Dichlorides ; poisoning ; Female ; Glucocorticoids ; therapeutic use ; Humans ; Male ; Middle Aged ; Poisoning ; drug therapy ; Retrospective Studies ; Treatment Outcome ; Young Adult

OBJECTIVETo explore the effects of 1,2-dichloroethane (1,2-DCE) on the cellular proliferation, cellular cycle and apoptosis of SW620 cells in vitro.

METHODSSW620 cells were exposed to 1,2-DCE at different concentrations for 0.5 and 1 h. MTT assay was used to detect the relative number and relative viability, the low cytometry (FCM) assay was utilized to measure the cell cycle and apoptosis.

RESULTSThe results of MTT assay showed that the cellular relative viability decreased with the 1,2-DCE's dose and exposure time. Compared with the DMSO group, the relative cellular viability of cells exposed to 1,2-DCE at the doses of 75, 100, 125, 150, 175, 200 µmol/L for 1 h decreased (P<0.05 or P<0.01). Compared with the groups exposed to 1,2-DCE for 0.5 h, the relative cellular viability of cells exposed to 175 µmol/L 1,2-DCE for 1 h decreased significantly (P<0.01). IC(50) of cellular proliferation in cells exposed to 1,2-DCE for 0.5 h was 89.41 µmol/L, and 95% confidence interval was 85.23 to 93.79 µmol/L. IC(50) of cellular proliferation in cells exposed to 1,2-DCE for 1 h was 87.68 µmol/L, and 95% confidence interval was 83.71 to 91.82 µmol/L. The results of FCM indicated that compared with the control group, the G(0)/G(1) phase in groups exposed to 1,2-DCE at the doses of 25, 50, 100, 150 and 200 µmol/L for 1 h decreased significantly (P<0.05 or P<0.01), the S phase in groups exposed to 1,2-DCE at the doses of 25, 50 and 100 µmol/L for 1 h reduced significantly (P<0.05 or P < 0.01), the G(2)/M phase in groups exposed to 1,2-DCE at the doses of 25, 50, 100, 150 and 200 µmol/L for 1 h increased significantly (P<0.05 or P<0.01). However, 1,2-DCE could not induce apoptosis of SW620 cells.

CONCLUSION1,2-DCE could inhibit the proliferation of SW620 cells, and arrest SW620 cells at G(2)/M phase, but could not induce the apoptosis of SW620 cells in vitro.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Ethylene Dichlorides ; toxicity ; Humans