Exposure to 1-bromopropane causes dose-dependent neurological abnormalities in workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the dose-effect relationship between 1-bromopropane (1-BP) exposure and health effects in workers.</p><p><b>METHODS</b>Occupational field investigations were conducted in 1-BP factories. Ambient 1-BP concentrations were detected with detection tube, and the 8 h time-weighted average individual exposure levels (TWA-8 h) were measured by passive sampler. Workers underwent questionnaire survey, neurological examination, nerve conduction velocity examination, vibration sensation test. routine blood test as well as blood biochemical test. According to TWA values or TWA x duration values, workers were divided into three dose groups for dose-effect relationship analysis. USEPA BMDS 2.1 software was applied to calculate 1-BP benchmark dose (BMD) and its 95% lower limit (BMDL).</p><p><b>RESULTS</b>The TWA-8h concentrations ranged from 0.35 to 535.19 mg/m3 (geo-mean 14.08 mg/m3). Dose-dependent analysis showed that the motor nerve distal latency (linear regression coefficient was 0.066 6), vibration sensation of toes (linear regression coefficient were 0.157 2 and 0.193 9), creatine kinase (linear regression coefficient was -1.05) and thyroid stimulating hormone levels (linear regression coefficient was 0.1024) of 1-BP exposed workers changed in a dose-dependent manner (P < 0.05). BMD calculation based on DL as 1-BP toxic effect endpoint showed that TWA-8h of the BMD values and BMDL values were 50.55 mg/m3 and 30.78 mg/m3, respectively.</p><p><b>CONCLUSION</b>1-BP causes dose-dependent changes in tibial nerve DL, vibration sensation, CK and TSH levels.</p>

Effects of 1-bromopropane on neurological and hematological changes of female exposed workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the health effects of 1-bromopropane (1-BP) on female exposed workers.</p><p><b>METHODS</b>Four 1-BP manufacturing plants were investigated. Workers were interviewed with questionnaire and examined with neurobehavioral core test battery, nerve conduction velocity tests of nervus tibialis and nervus suralis, vibration sensation test, hematological and biochemical tests. Ambient 1-BP concentration was measured with detection tube, and time-weighed average levels of individual workers were estimated with passive samplers.</p><p><b>RESULTS</b>1-BP concentration in the plants ranged from 0 to 402.40 mg/m3 (Geomean 32.19 mg/m3). Time-weighted average exposure levels (TWA-8 h) ranged from 0.35 to 535.19 mg/m3 (Geomean 14.08 mg/m3). Compared with the control group, 1-BP exposed workers showed reduced motor nerve conduction velocity [(44.8 +/- 8.7) m/s] and sensory nerve conduction velocity [(45.5 +/- 4.9) m/s], prolonged distal latency [(7.5 +/- 2.1) ms], reduced toe vibration perception, and altered neurobehavior parameters(POMS vigor, tension, anxiety, confusion) significantly (P < 0.05). As to hematological and biochemical indicators, the exposed workers showed decreased white blood cell count [(5.6 +/- 2.17) x 10(3)/microl], red blood cell count [(3.9 +/- 0.4) x 10(6)/microl], hemoglobin [(121.1 +/- 14.5) g/L] and creatine kinase [(82.0 +/- 27.5) IU/L] (P < 0.05), and increased serum total protein (8.0 +/- 0.5 g/dl), lactate dehydrogenase [(335.2 +/- 356.6) IU/L], thyroid-stimulating hormone [(3.6 +/- 2.3) microIU/ml] and follicle-stimulating hormone levels (18.7 +/- 24.4 mIU/ml) (P < 0.05).</p><p><b>CONCLUSION</b>1-BP exposure may affect peripheral nerves and central nervous system, and lead to abnormal hematological and biomedical indicators.</p>

Comparison on urinary 1-hydroxypyrene concentrations between coke oven workers and non-occupational exposed individuals / 中华预防医学杂志

<p><b>OBJECTIVE</b>To compare the urinary 1-hydroxypyrene (1-OHP) concentrations between coke oven workers and non-occupational exposed individuals and to investigate the possible impact factors.</p><p><b>METHODS</b>Spot end-of-shift urine samples were collected in 265 coke oven workers and spot morning urine samples in 226 non-occupational exposed individuals. External exposure levels and possible confounding factors were assessed by environmental polycyclic aromatic hydrocarbons (PAH) monitoring and uniform questionnaire, and the urinary 1-OHP concentrations determined by high performance liquid chromatography (HPLC), were used to compare the different urinary 1-OHP levels between different research populations and to explore the effects of several factors such as external exposure levels, smoking habits, alcohol consumptions, age and body mass index (BMI).</p><p><b>RESULTS</b>The urinary 1-OHP concentrations in coke oven workers were significantly higher than those in non-occupational exposed individuals (13.49, 6.56, 1.38 and 0.35 micromol/mol creatinine for topside workers, side-oven workers, bottom side workers and references, respectively, P < 0.001; the same trends for the percentage of the level over 2.3 micromol/mol creatinine: 94.81%, 84.73%, 35.09% and 0.88%, P < 0.001). The control individuals who smoked over 20 cigarettes per day possessed higher urinary 1-OHP concentrations than the non-smokers (adjusted geometric mean: 0.47 and 0.31 micromol/mol creatinine, respectively, P < 0.05). Alcohol drinking references possessed lower urinary 1-OHP levels than the non-drinkers (adjusted geometric mean: 0.33 and 0.47 micromol/mol creatinine, respectively, P < 0.05).</p><p><b>CONCLUSION</b>Coke oven workers should be exposed to a high level of urinary 1-OHP, especially for topside workers and side-oven workers. Background urinary 1-OHP levels in non-occupational exposed individuals should be related to smoking habits and alcohol consumptions.</p>