[Analysis on the disease burden and its impact factors of coal worker's pneumoconiosis inpatients].

OBJECTIVE: To obtain the baseline data and decision of quantitative analysis for the allocation of scarce health care resources,and for the health policymaking about easing the disease burden, to provide estimation of the economic costs and the disability-adjusted life years (DALYs) loss of the coal worker's pneumoconiosis (CWP) and to explore the influencing factors of the disease burden. METHODS: The CWP inpatients from the Institute of Occupational Diseases Prevention and Control of a Coal Mining Group for 2011 were recruited in the study. Multiple dimensions of the disease burden were measured in the inception cohort of the 194 CWP inpatients: the direct economic burden, the indirect economic burden and the DALYs loss. The direct economic burden of the inpatients included hospitalization expenses and food allowances and nutritional supplements. The indirect economic burden was estimated using the DALYs and human capital approach,and the influencing factors of hospitalization expenses were analyzed in this study. RESULTS: The estimated direct economic burden for the 194 CWP inpatients for 2011 was approximately 4.68 million yuan and direct burden per capita was 24 108.05 yuan, and their indirect burden about 6.98 million yuan and indirect burden per capita 35 977.36 yuan. The study discovered that 1 681.53 health years were lost for the CWP inpaitents and per capita health years loss (8.67±3.65) years. CONCLUSION: The medical cost, the indirect cost and the DALYs loss of CWP are all sizable. Age and length of stay in the hospital are the major influencing factors for high hospitalization expenses. The hospitalization expenses of the CWP inpatients increase with their age and length of stay in the hospital. Taking effective measures to reduce the morbility is the key point to reduce the CWP burden.

[The improvement of determination method of carbon disulfide in workplace air with gas chromatography].

OBJECTIVE: Establishment of determination method of carbon disulfide in charcoal tube with low toxicity solvents desorption-gas chromatography. METHODS: Four types of solvent with low toxicity are applied respectively as substitution of benzene to desorb the carbon disulfide in samples of charcoal tube. The signal strength and desorption efficiency of the detector are compared by using different solvents. RESULTS: Chloroform has been considered as the best alternative solvent of benzene. Carbon disulfide has a good linearity (R = 0.9997) over the concentration of 0 ∼ 54.7 µg/ml, detection limit can reach 0.2 µg/ml. When the sampling volume is 3.0 L, the minimum detectable concentration is 0.07 mg/m(3). CONCLUSION: With the use of chloroform, the health hazard to laboratory personnel and environment pollution as well as the costs of experiments are reduced.

[The optimization of 2-thiothiazolidine-4-carboxylic acid back extraction in urine and determination by HPLC].

OBJECTIVE: Establishment of determination method of 2-thiothiazolidine-4-carboxylic acid (TTCA) in urine with HPLC. METHODS: A volume of 0.5 ml hydrochloric acid (2 mol/L) and 0.5 ml pure water was added into 1 ml urine, and then extracted by 4 ml of diethyl ether by shaking for 2 min. Remove the water phase in a tube with plug and extract again, mix the two extraction diethyl ether together, take 4 ml by adding 2 ml borax-monopotassium phosphate buffer and shaking for 2 min to extract, then take the water phase to detect. A C(18) column and UV detector were used for separating and detecting. The wavelength was 273 nm, the flow rate was 1.0 ml/min, and the injection volume was 20 µl. RESULTS: TTCA has a good linearity (r = 0.9995) over the concentration of1 1 ∼ 10 µg and the minimum detectable concentration of TTCA in urine was 0.1 µg/ml. The within-day precision (RSD) were 8.4%, 3.0% and 1.7%, the between-day precision (RSD) were 11%, 3.8%, 1.9%, respectively. The extraction recovery were between 80% ∼ 102%. CONCLUSION: The method was accurate and sensitive to detect TTCA in urine.

[The rervising of biological exposure index for carbon disulfide exposuring].

OBJECTIVE: To study the biological exposure index of carbon disulfide in China. METHODS: High-performance liquid chromatography (HPLC) was used to detect the levels of 2-thiothiazolidine-4-carboxylic acid (TTCA) in the urine of the workers after working shift end, Gas chromatography was used to detect the concentrations of the carbon disulfide in the workplace air. The relationship between the urine TTCA levels and the concentrations of the carbon disulfide was analyzed, the biological exposure index and judgement result from PC-TWA were compared. RESULTS: The levels of TTCA in urine of workers occupationally exposed to carbon disulfide were closely and positively related with the concentrations of the carbon disulfide in the workplace air. The regression equation was Y = 0.265X - 0.165, The biological exposure index of carbon disulfide were calculated by regression equation according to occupational exposure limits of carbon disulfide in China. CONCLUSION: The biological exposure index of CS(2) in China might be revised for 1.2 mg/g Cr.

[Determination of dimethyl ether in workplace air with gas chromatography].

OBJECTIVE: To develop determination of dimethyl ether in workplace air by GC. METHODS: Dimethyl ether were sampled with solvent desorption active carbon tube. The sampled carbon tube were desorbed by carbon tetrachloride, Elite-WAX column was used with temperature programmed from 40 to 90 degrees C, and the carrier gas programmed from 1.4 - 2.5 ml/min. RESULTS: There was a good linearity (r = 0.9999) over the concentration of 0-63.91 microg/L, detection limit can reach 0.75 microg/ml. CONCLUSION: This method proved to be accurate and sensitive, to meet the determination of the dimethyl ether in workplace air.

[Determination of hydrogen selenide in workplace air with atomic fluorescence].

OBJECTIVE: To determined hydrogen selenide in workplace air with atomic fluorescence. METHOD: Hydrogen selenide were sampled with 0.1 mol/L sodium hydroxide solution in multi-hole absorbing tubes. The sampled absorbing solution were digested with (9+1) nitric acid/perchloric acid. The selenide in sample were reduced by potassium borohydride in 5.0% hydrochloride solution and determined with atomic fluorescence. RESULTS: There was a good linearity (r=0.9999) over the concentration of 0-150 microg/L, The precision of low, middle and high concentration were 3.1%, 7.4% and 6.7%, respectively. The sample collection rate can reach 99%. CONCLUSION: The method was accurate and sensitive to detect hydrogen selenide in workplace air.

[The surface biomarkers of sputum cells in coal mine workers and patients with pneumoconiosis].

OBJECTIVE: To explore the significance of intercellular adhesion molecule -1 (CD54 or ICAM-1), epidermal growth factor receptor (EGFR) and platelet-derived factor (PDGF) in sputum cells of workers exposed to dust and patients with pneumoconiosis for the early diagnosis of pneumoconiosis. METHODS: The subjects included 62 workers exposed to dusts, 51 workers not exposed to dusts, 22 patients with pneumoconiosis and 10 healthy controls. The respiratory sputum technique was used to collect the sputum samples and the biomarkers (ICAM-1, EGFR and PDGF) of the sputum samples were detected with the sputum samples. RESULTS: When the exposure group was compared with non-exposure group, there were no significant differences of surface biomarkers (ICAM-1, EGFR and PDGF) in sputum cells (neutrophil leucocytes, macrophages, lymphocytes and acidophilic/basophil leucocytes). As compared with other workers exposed to dusts, the surface CD54 and EGFR expression levels increased significantly and the surface PDGF expression level decreased significantly in workers exposed to dusts for 10 years (P<0.05). As compared with controls, the CD54 and EGFR expression levels of sputum cells increased significantly and the PDGF expression level of sputum cells decreased significantly in patients with pneumoconiosis at the stages of I and II + mI (P<0.05). CONCLUSION: The expression levels of the surface CD54, EGFR and PDGF of sputum cells in workers exposed to dusts and patients with pneumoconiosis changed, which may be useful for early detecting pneumoconiosis.and patients is changed, which may be meaningful for early detection of pneumoconiosis.