ABSTRACT
OBJECTIVE@#The study aimed to estimate the benchmark dose (BMD) of coke oven emissions (COEs) exposure based on mitochondrial damage with the mitochondrial DNA copy number (mtDNAcn) as a biomarker.@*METHODS@#A total of 782 subjects were recruited, including 238 controls and 544 exposed workers. The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction. Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95% confidence lower limit (BMDL).@*RESULTS@#The mtDNAcn of the exposure group was lower than that of the control group (0.60 ± 0.29 vs. 1.03 ± 0.31; P < 0.001). A dose-response relationship was shown between the mtDNAcn damage and COEs. Using the Benchmark Dose Software, the occupational exposure limits (OELs) for COEs exposure in males was 0.00190 mg/m 3. The OELs for COEs exposure using the BBMD were 0.00170 mg/m 3 for the total population, 0.00158 mg/m 3 for males, and 0.00174 mg/m 3 for females. In possible risk obtained from animal studies (PROAST), the OELs of the total population, males, and females were 0.00184, 0.00178, and 0.00192 mg/m 3, respectively.@*CONCLUSION@#Based on our conservative estimate, the BMDL of mitochondrial damage caused by COEs is 0.002 mg/m 3. This value will provide a benchmark for determining possible OELs.
Subject(s)
Male , Female , Animals , Coke , Polycyclic Aromatic Hydrocarbons , DNA Copy Number Variations , Benchmarking , Occupational Exposure/analysis , DNA, Mitochondrial/genetics , DNA DamageABSTRACT
OBJECTIVE: To observe the levels of four hydroxylated metabolites of polycyclic aromatic hydrocarbons(PAHs)in the urine of coke workers and its influencing factors.To explore the feasibility of using PAHs as biomarkers for exposure of coke oven emissions(COEs).METHODS: A cross-sectional survey was used to compare 261 coke oven workers in a coke oven plant as exposure group with 111 workers without COEs exposure in an oxygen making plant as control group.Ultra high liquid chromatography-mass spectrometry was used to detect four hydroxylated metabolites of PAHs,including1-hydroxypyrene(OHP),1-hydroxynaphthalene(OHN),2-OHN and 3-hydroxyphenanthrene,in urine of these two groups.RESULTS: The levels of four hydroxylated metabolites of PAHs in urine in exposure group were higher than that of the control group(P<0.01).The levels of urinary 1-OHP,1-OHN,2-OHN were followed by the sequence of bottomoven,side-oven,and top-oven subgroups among the exposure group(P<0.05).The multiple linear regression results indicated that the levels of urinary 1-OHP,1-OHN,2-OHN were correlated with COEs exposure(P<0.05),after adjusting the confounding factors of gender,age,length of service,smoking status and alcohol drinking status.The levels of urinary 1-OHP,1-OHN,2-OHN of the exposure group increased with the increase of COEs exposure levels showing a dose-effect relationship(P<0.01).The levels of 1-OHN and 2-OHN were associated with smoking apart from COEs exposure(P<0.01).CONCLUSION: The urinary 1-OHP can be used as a reliable biomarker for the evaluation of internal exposure to COEs.The 1-OHN and 2-OHN can be used as adjuvant biomarkers.
ABSTRACT
OBJECTIVE: To establish the cell model using human leukemia cell line HL-60 for exposure of coke oven emissions( COE) in vitro and to explore the mechanism of COE-induced acute toxicity in HL-60 cells. METHODS: HL-60 cells were collected in their logarithmic growth phase and cultured in medium that had final concentrations of COE in 2. 5,5. 0,10. 0 and 20. 0 mg / L for 24 hours. Cell survival rate was examined by CCK-8 assay. The cytotoxicity was evaluated using lactate dehydrogenase release assay. Reactive oxygen species( ROS) production was determined by the 2',7'-dichlorofluorescein diacetate and nitroblue tetrazolium method. The activation of nuclear factor-κB( NF-κB) pathway was evaluated by western blot. RESULTS: With the increasing exposure concentrations of COE,the cytotoxicity of HL-60 cells increased( P < 0. 01),the cell survival rate decreased( P < 0. 01),intracellular ROS decreased( P < 0. 01),whereas extracellular ROS increased( P < 0. 01). These changes had a dose-effect relationship. The levels of phospho-nuclear factor-kappa B p65 and phospho-inhibitor of kappa Bα were higher in all the COE-treated cells compared with untreated cells( P < 0. 05),with no dose-effect relationship. CONCLUSION: COE could cause acute toxicity in HL-60 cells in a doseeffect relationship. The mechanism may be related to the COE-induced in-balanced ROS release and removal,leading to the activation of NF-κB pathway. HL-60 cells can be used as a common cell line for COE hematotoxicity analysis.