Humans ; Indium ; toxicity

Objective: To summarize the clinical characteristics of occupational asthma and provide a basis for revising the diagnosis of occupational asthma in China. Methods: Taking "occupational asthma" , "occupational bronchial asthma" and "bronchial provocation test at work site" as key words, the case reports of occupational asthma in China were retrieved. The general data, latent period, allergen, clinical manifestation, and diagnostic methods were analyzed. Results: A total 318 cases from 14 published literatures were reported.The incidence of male and female is basically similar. The average age of onset is 38 years, and the latent period is from 2 months to 19 years. The top 3 allergens were isocyanates, penicillin and cephalosporins, formaldehyde. During the diagnosis process, 48.8% of the patients were diagnosed by bronchial provocation test, and 19 cases were diagnosed according to the specific IgE antibody. Only 1 case was diagnosed according to the specific skin test. Conclusion The etiological diagnosis of occupational asthma is not easy. Nearly half of the patients in our country have been diagnosed as occupational asthma by bronchial provocation test at work site. How to identify the relationship between occupational exposure and the occurrence of asthma is one of the main problems we need to solve.

Humans ; Occupational Health ; Occupational Health Services ; standards ; Population Surveillance ; Program Evaluation

Objective: The method was established for the detection of whole blood indium and serum indium. By comparing the results of two samples, it is possible to explore the significance of whole blood indium and serum indium in the population exposed to indium compounds. Methods: According to GBZ/T 295-2017 and GBZ 294-2017, the whole blood and serum samples were diluted 20 times by 0.5% nitric acid solution (including 0.05% Triton X-100) . Under the standard mode of inductively coupled plasma mass spectrometry (ICP-MS) , whole blood indium and serum indium of indirect exposure group, low exposure group and high exposure group in an indium mine were detected with 20 μg/L rhodium standard solution as internal standard. Results: This method has a working range of 0.00~5.00 μg/L and a correlation coefficien t>0.999. The detection limit and quantitative lower limit of whole blood indium were 0.076 μg/L and 0.26 μg/L respectively. Those of serum indium were 0.06 μg/L and 0.20 μg/L accordingly. The recovery rates of serum and whole blood samples were 88.5%~95.6% and 93.0%~101%. Intra batch precisions were 1.3%~4.4% and 1.9%~3.5% and inter batch precision were 2.4%~6.1% and 2.1%~4.6% in two samples. There were no significant differences between whole blood indium and serum indium in indirect exposure group. The serum indium level was lower than the detection limit in 3 cases, while their whole blood indium was only below the quantitative lower limit. However, in other groups whole blood indium level was significantly higher than serum indium level (P<0.05) and even was two-fold in the high exposure group. Conclusion The detection of whole blood indium is more sensitive than that of serum indium, which can reflect the internal exposure level more accurately in exposure population. Therefore, the whole blood indium is of more important referential value to health examination and poisoning diagnosis in the population exposed to indium and its compounds.

Objective: To observe the effect of nerve growth factor (NGF) and Mecobalamin on chronic peripheral neuropathy in rats induced by 1-bromopropane. Methods: 36 male SD rats were exposed to 1-bromopropane vapor at concentrations of 4 000 mg/m³, 6 hours per day, 5 days per week for 12 weeks. The rats were randomed divided into 4 groups, and treated by Mecobalamin for 300 μg/kg qd, NGF for 40 μg/kg qd, Mecobalamin+NGF with the dose as mentioned above, respecively. The control group were fed in normal condition. The changes of Sciatic nerve conduction velocity (NCV) , electromyography (EMG) and pathology were observed 30 days later. Results: The nerve conduction velocity were decreased in all the rats. Compared with the control group, the motor nerve conduction velocity (MCV) was improved in group Mecobalamin and group Mecobalamin+NGF, The difference was statistically significant, as the sensory nerve conduction velocity (SCV) was improved only in group Mecobalamin+NGF. Sciatic nerve biopsy observed by electron microscope showed that myelinated nerve fibers were obvious swelling, lamellar separation, partial myelin vacuolization, and axonal degeneration. After treatment with exogenous nerve growth factor, the number and severity of damaged nerve fibers were restored. Conclusion Exogenous nerve growth factor contributes to the recovery of peripheral nerve damage induced by 1-bromopropane.

Objective: To study the electrophysiological changes and pathological characteristics of peripheral nerve in rats exposed to 1-bromopropane through chronic inhalation. Methods: 40 male SD rats were randomed divided into 4 groups, and exposed to 1-bromopropane vapor at concentrations of 1 000 mg/m³, 2 000 mg/m³, 4 000 mg/m³ and fresh air respectively, 6 hours per day, 5 days per week for 12 weeks. The changes of nerve conduction velocity (NCV) , electromyography (EMG) and pathology were observed. Results: After 4 weeks of exposure, the body weights of high dose group are lower than that of the control group. Compared with the control group, the high and medium dose group have a decline in MCV and CMAPs, while SCV and SNAPs descend in the high dose group (P<0.05) . The EMG examination showed that there are denervation changes in high dose group. Sciatic nerve biopsy observed by electron microscope showed that axonal degeneration and demyelination coexist in the rats exposed to high concentration. Conclusion Chronic inhalation of 1-bromopropane at the concentration of 4 000 mg/m³ can cause peripheral nerve injury, which is characterized by axonal degeneration and demyelination. Axonal degeneration is the main pathological change.

Objective: To study the airway inflammation feature difference in the patients with occupational pulmonary thesaurosis induced by iron. Methods: Induced sputum samples were obtained from 20 healthy men, 20 patients with stable asthma, 25 patients with occupational pulmonary thesaurosis induced by iron. Differential cell counts in induced sputum were examined. The levels of supernatant IL-8 were measured by ELISA. Results: The pulmonary function result was normal in the patients with pulmonary thesaurosis., their FVC (4.1±1.2) L was similar to FVC (4.3±0.9) L in mal group; but their FEV_1.0 (2.9±0.9) L、FEV₁/FVC (71.9%±5.4%) were lower than normal group’s FEV_1.0 (3.2±0.7 L) 、FEV_1.0/FVC (79.2%±9.9%) , and were hirher than asthma group’s FEV₁ (2.5±0.8) L and FEV_1.0/FVC (68.7%±6.1%) . In induced sputum, macrophages percentage in patients with pulmonary thesaurosis (54.3%±9.7%) was higher than asthma group and normal group (48.4±6.4, 51.9±7.3, P<0.05) , neutrophils percentage in patients with pulmonary thesaurosis group (43.9%±7.6%) was higher than asthma group and normal group (41.3%±7.1%, 39.8%±6.9%, P<0.05) , eosinophils percentage in patients with pulmonary thesaurosis group (0.3%±0.1%) was lower than asthma group (2.8±0.3, P<0.05) , lymphocytes percentage in patients with pulmonary thesaurosis group (2.0%±0.4%) was lower than asthma group (4.7±0.6, P<0.05) ; the sputum levels of IL-8 in patients with pulmonary thesaurosis group (914.7±24.3) pg/ml was higher than asthma group and normal group (747.9%±16.8 pg/ml, (405.4±13.7) pg/ml, P<0.05) . Conclusion Macrophages and IL-8 may play an important role in the pathogenesis of airway inflammation after long-term inhalation of iron and its compounds, the airway function in patients of occupational pulmonary thesaurosis was found damaged.

Objective:To investigate the characteristics of inflammatory response in BALB/cA-nu mice induced by oral 1, 2-dichloropropane (1, 2-DCP) , and to provides theoretical reference for further study of subchronic, chronic toxicity and carcinogenic mechanism.Methods:From October 2018, Clean grade healthy BALB/cA-nu mice were randomly divided into 5 groups with 10 mice in each group. And 860, 1150, 1500, 1950, 2535 mg/kg 1, 2-DCP were given by gavage respectively. Meanwhile, blank group and solvent control group (corn oil) were set up. Blood samples were collected from eyeballs and liver and bile tissues were collected for histopathological examination within 24 hours after exposure. The expression of alanine aminotransferase (ALT) , total bilirubin (TBLI) , C-reactive protein (CRP) , interleukin-6 (IL-6) , tumor necrosis factor-α (TNF-α) and tumor necrosis factor-β (TNF-β) were detected by enzyme-linked immunosorbent assay.Results:With the increase of the dose of 1, 2-DCP, the number of microbubbles in liver cells and the infiltration of inflammatory cells increased gradually. No pathological changes were found in the gallbladder. Compared with the blank group and solvent control group, the content of serum ALT in each exposure group was increased, the serum levels of IL-6 and TNF-β in 860, 1150, 1950 and 2350 mg/kg exposure groups were increased, the serum TNF-α and TBLI levels in 1 950, 2535 mg/kg groups were significantly higher ( P<0.05) . The levels of ALT, TBLI and TNF-β in serum of female mice were significantly different ( P<0.05) . There were significant differences in ALT, TBLI, CRP, IL-6, TNF-α, TNF-β in serum of male mice ( P<0.05) . Conclusion:Oral 1, 2-DCP may cause acute liver injury in BALB/cA-nu mice and increase the expression of serum inflammatory factors. Moreover, the types of inflammatory factors activated in male mice are more than those in female mice.

Objective:Establishing an analysis method for the detection of six arsenic compounds trivalent arsenic, pentavalent arsenic, methyl arsenic, dimethyl arsenic, arsenical choline and arsenical betaine in urine by high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) and providing a theoretical basis for health assessment of arsenic poisoning patients.Methods:HPLC-ICP-MS was used to detect six arsenic compounds with the hamilton PRP-X100 column and aqueous ammonium phosphate in a gradient elution as mobile phase.Results:There was a good linear relationship in the selected range of six arsenic compounds evidenced by a linear correlation coefficient greater than 0.999. The detection limit of 6 arsenic compounds was 0.46~0.57 μg/L, and the minimum quantitative concentration were 1.52~1.91 μg/L. The recovery rates of six arsenic compounds were 96.5%~106.4%, The within-run and between-run relative standard deviation was 2.9%~6.2% and 3.8%~8.7%.Conclusion:The established method with high accuracy and precision is suitable for detecting arsenic levels in urine of occupational arsenic exposure population.

Objective:To explore the correlation between urinary arsenic and health effects through the determination and analysis of urinary arsenic levels in occupational arsenic exposed workers.Methods:In November 2021, 95 workers exposed to arsenic and its inorganic compounds and 31 administrative personnel from a non-ferrous metal smelter in Yunnan Province were selected as the contact group and control group, respectively. Urine forms of arsenic, blood tumor markers, liver function were detected, and micronucleus test was used to analyze the chromosome damage. The correlation between urine forms of arsenic and health effects were analyzed.Results:Compared with the control group, the concentrations of urinary trivalent inorganic arsenic (iAs 3+) , pentavalent inorganic arsenic (iAs 5+) , inorganic arsenic (iAs=∑iAs 3++iAs 5+) , monomethyl arsenic (MMA) , dimethyl arsenic (DMA) and urinary arsenic (∑iAs+MMA+DMA) at the end of class in contact group were higher ( P<0.05) . There was no statistically significant difference in blood tumor markers and liver function indicators between the two groups ( P>0.05) . Compared with the control group, the peripheral blood micronucleus rate and cell micronucleus rate in the contact group were significantly increased ( P<0.05) . The urinary arsenic, iAs 5+, inorganic arsenic and DMA were positively correlated with peripheral blood micronucleus rate in contact group ( rs=0.48, 0.34, 0.37, 0.23, P<0.05) , and the urinary arsenic, iAs 5+, DMA were positively correlated with peripheral blood micronucleus rate ( rs=0.48, 0.34, 0.26, P<0.05) . Conclusion:There is a significant correlation between different valence states of arsenic in the urine and abnormal health effects of occupational arsenic exposed workers. It is necessary to strengthen the detection of arsenic species in the urine of occupational arsenic exposed workers to better protect their health.