1.Control of Ammonia Pollution in Indoor Air
Jin YANG ; Xu-Yong LENG ; Ze-Qin LI ;
Journal of Environment and Health 1992;0(04):-
Objective To understand the ammonia pollution level in indoor air in Chengdu city,China.Methods 50 newly decorated houses included resident houses,offices and public places were selected in Chengdu city.The national standard method of China-Berthelot spectrophotometry was used to determine the concentration of ammonia in indoor air.Results The result showed that the average concentration of ammonia was 0.307 mg/m3,the rate of exceed standard limit was 58.33%,the highest concentration was 0.598 mg/m3,which was almost three times of the national standard limit.At 4 months after decoration,the concentration of ammonia decreased near to the national standard limit(0.20 mg/m3).Conclusion As the time goes on,the concentration of ammonia in indoor air shows a downtrend,and in general,it will reach to the safe level in 4 months after decoration,so it is suggested to move in the newly decorated houses after five months since the decoration finished will be better for human health.
2.Mechanisms for the regulatory effect of prostaglandin E2/ prostaglandin E receptor 4 on high mobility group box-Ⅰ protein in lipopolysaccharide-induced sepsis in mouse peritoneal macrophage
Xiaoliang WANG ; Yong ZHANG ; Yanna SI ; Yajie XU ; Hongguang BAO ; Xiaoming BAI ; Jing LENG
Journal of Central South University(Medical Sciences) 2017;42(8):889-898
Objective:To explore the effect of prostaglandin E2 (PGE2) on the expression of high mobility group box-1 protein (HMGB1) in peritoneal macrophages of septic mice and its possible mechanisms.Methods:Ihe mouse peritoneal macrophages were isolated and cultured by conventional methods.The model of inflammation was established by using lipopolysaccharide (LPS) to incubate with mouse peritoneal macrophages.The PGE2,prostaglandin E receptor (EP) 4 agonist,EP4 RNAi,and DN.CREB inhibitory plasmid were used to interfere with the LPS-treated mouse peritoneal macrophage.The levels of HMGB 1 was determined by Western blot.Results:Compared with LPS alone treatment,the expression of HMGB 1 in peritoneal macrophages was increased obviously after 24 h by treatment with PGE2 and LPS,and it was also increased after the combined treatment of EP4 receptor agonist with LPS for 24 h (both P<0.05);compared with the PGE2+LPS treatment,the level of HMGB1 was decreased after knockdown of EP4 receptor expression (P<0.05);compared with EP4 receptor agonist +LPS treatment,there was no difference in HMGB1 levels in mice after the treatment with DN.CREB plasmid to suppress CREB function (P>0.05);compared with LPS alone treatment,the combined treatment of EP4 receptor agonist with LPS for 24 h could up-regulate the phosphorylation of epidermal growth factor receptor (EGFR) and protein kinase B (Akt) thr308 (P<0.05),which were blocked by EGFR inhibitor.Once Akt specific inhibitor was used before EP4 and LPS treatment,the expression of HMGB1 was declined (P<0.05).Conclusion:PGE2 can up-regulate the expression of HMGB1 in sepsis of peritoneal macrophages through EP4 receptor,which may be related to the activation of EGFR/PI3K/Akt signaling pathway.
3.The impact of perioperative function exercises on hidden blood loss in elderly patients with total hip replacement.
Guoyin LIU ; Dongmei ZHU ; Yong ZHANG ; Mengru WANG ; Yuansheng XU ; Lei BAO ; Nannan LENG ; Zhengqian YANG ; Jianmin CHEN
Chinese Journal of Surgery 2016;54(4):258-263
OBJECTIVETo investigate the effects of initiative and passive perioperative function exercises on hidden blood loss (HBL).
METHODSTwo hundreds and thirty elderly patients with hip fractures aging from 67 to 87 years (average age of 73.6 years) who underwent total hip replacement were included. By the intensity and the manner of perioperative function exercises, patients were divided into four groups: little initiative function exercises group (group A, n=51), little initiative and passive function exercises group (group B, n=54), normal initiative function exercises group (group C, n=65), normal initiative and passive function exercises group (group D, n=60). The true total blood loss, HBL and their proportion on the original blood volume and total blood loss was calculated depending on height, weight, intra-operative blood loss, post-operative blood loss, pre- and post-operative hematocrit, and blood transfused. According to the proportion of mean HBL on total blood loss, patients were divided into low HBL group and high HBL group. The data were analyzed by t test.
RESULTSThe mean HBL was 517 ml, 41.9% of the total blood loss. Thereinto, the mean HBL was 695 ml in group A, 49.3% of the total blood loss, the prevalence of high HBL was 66.7% (34/51); the mean HBL was 625 ml in group B, 46.9% of the total blood loss, the prevalence of high HBL was 59.3% (32/54); the mean HBL was 446 ml in group C, 38.4% of the total blood loss, the prevalence of high HBL was 30.8% (20/65); the mean HBL was 346 ml in group D, 32.3% of the total blood loss, the prevalence of high HBL was 20.0% (12/60). Mean HBL, mean HBL/total blood loss, prevalence of high HBL were lower in group C than that in group A and group B (all P<0.05); and were lower in group D than that in group C (all P<0.05). The prevalence was 57.4% (132 cases) in low HBL group, and 42.6% (98 cases) in high HBL. The proportion of little initiative function exercises patients in high HBL group was obviously higher than that in low HBL group (P<0.05).
CONCLUSIONSThe intensity and the manner of perioperative function exercises are strongly associated with the HBL in elderly patients with total hip replacement. The initiative combined with the passive function exercises could be effectively prevent and reduce the incidence of high HBL.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip ; Blood Loss, Surgical ; Exercise Therapy ; adverse effects ; Hip Fractures ; surgery ; Humans ; Postoperative Hemorrhage
4.The epidemiology character of the 503 residual paralysis of acute flaccid paralysis cases.
Huan-ying ZHENG ; Xue GUO ; Leng LIU ; Ping HUANG ; Yong-jie LIN ; Yong ZHANG ; Chang-wen KE ; Wen-bo XU
Chinese Journal of Experimental and Clinical Virology 2008;22(6):413-415
OBJECTIVEAnalyze the epidemiology character of the residual paralysis(RP) of acute flaccid paralysis (AFP) in Guangdong during 1994-2007.
METHODSThe viruses isolated from the excrement of RP cases were identified and typed in Guangdong from 1994 to 2007. Statistics analysis was performed to reveal the relationship among the immunization history,age,gender and the distribution of the etiology.
RESULTSA total of 503 RP cases were reported. 150 of which were isolated with PV and 59 were isolated with NPEV. From 1994 to 2007, The PV isolating rate ranged from 18.92% to 47.06% and was higher in winter and spring, while the NPEV isolating rate ranged from 4.17% to 25.00%. and was higher in summer and autumn. The PV isolating rate decreased as the age increased,and its isolating rate (61.11%) was highest in "0" year group. The PV isolating rate of the population of < or =2 times OPV was far higher than 3 times. The PV and NPEV isolating rate of the RP cases was higher than without RP.
CONCLUSIONThe case with RP caused by wild poliovirus wasn't found from 1994 to 2007 in Guangdong, but the relationship of RP case was observed between < or =2 years group and < or =1 time OPV, and NPEVs probably are the potential etiological agent that cause children RP.
Acute Disease ; Adolescent ; Child ; Enterovirus ; classification ; isolation & purification ; Enterovirus Infections ; epidemiology ; immunology ; physiopathology ; prevention & control ; Humans ; Immunization Programs ; Infant ; Infant, Newborn ; Male ; Paralysis ; virology ; Paraplegia ; complications ; epidemiology ; Poliovirus ; isolation & purification ; Population Surveillance ; Risk Assessment ; Serotyping ; Vaccination
5.Observation on the recovery effect of continuous infusion of dexmedetomidine combined with oxycodone in anesthesia intensive care unit for elderly patients undergoing thoracoscopic radical resection of lung cancer
Xin LENG ; Xin XU ; Yongling LIU ; Yong ZHANG ; Yanna SI ; Baolin CHEN ; Zhonghua LUO
Chinese Journal of Postgraduates of Medicine 2023;46(3):230-236
Objective:To compare the recovery effect of continuous infusion of dexmedetomidine combined with oxycodone or sufentanil in the anesthesia intensive care unit (AICU) in elderly patients after thoracoscopic radical surgery for lung cancer.Methods:Using the method of prospective study, 80 elderly lung cancer patients underwent selective thoracoscopic radical surgery under general anesthesia in Nanjing First Hospital from February 2021 to May 2022 were selected. The patients were divided into dexmedetomidine combined with sufentanil group (S group) and dexmedetomidine combined with oxycodone group (Q group) by random digits table method with 40 cases each group. On the basis of routine monitoring and treatment after operation, the patients in Q group were continuously injected with oxycodone 0.03 mg/(kg·h) and dexmedetomidine 0.4 μg/(kg·h) through analgesia pump, the patients in S group were continuously injected with sufentanil 0.03 mg/(kg·h) and dexmedetomidine 0.4 μg/(kg·h) through analgesia pump. The wake-up time, extubation time, awakening quality (Aldrete score and bucking score) and comfort level (Bruggrmann comfort scale score, BCS score) after entering the AICU were record; the sedation score (Ramsay score) and pain relief score (numerical rating scale score, NRS score) and hemodynamic changes (mean arterial pressure and heart rate) 3, 5, 7, 10 and 14 h after entering the AICU were record; the level of serum inflammatory factors, including tumor necrosis factor (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) immediately, 5 h and 14 h after entering the AICU; press times of analgesia pump, adverse events, bleeding volume of drainage tube during AICU and overall satisfaction score when leaving the AICU were record.Results:The bucking score in Q group was significantly lower than that in S group: (1.02 ± 0.77) scores vs. (1.88 ± 0.34) scores, the Aldrete score and BCS score were significantly higher than those in S group: (8.93 ± 0.25) scores vs. (5.97 ± 0.32) scores and (3.03 ± 0.32) scores vs. (0.93 ± 0.52) scores, and there were statistical differences ( P<0.01); there were no statistical difference in wake-up time and extubation time between two groups ( P>0.05). There were no statistical difference Ramassy score, NRS score 3 and 5 h after entering the AICU, mean arterial pressure and heart rate between two groups ( P>0.05); the Ramassy score 7, 10 and 14 h after entering the AICU in Q group was significantly lower than that in S group, the NRS score, mean arterial pressure and heart rate were significantly lower than those in S group, and there were statistical differences ( P<0.01). There were no statistical differences in TNF-α, IL-6 and CRP immediately after entering the AICU between two groups ( P>0.05); the TNF-α, IL-6 and CRP 5 and 14 h after entering the AICU in Q group were significantly lower than those in S group, and there were statistical difference ( P<0.01). The press times of analgesia pump, bleeding volume of drainage tube and the incidences of nausea vomiting, respiratory depression, lethargy, restlessness, fever and lung infection in Q group were significantly lower than those in S group: (4.63 ± 1.10) times vs. (18.80 ± 1.54) times, (129.67 ± 4.14) ml vs. (164.00 ± 8.14) ml, 10.0% (4/40) vs. 52.5% (21/40), 2.5% (1/40) vs. 25.0% (10/40), 7.5% (3/40) vs. 47.5% (19/40), 0 vs. 20.0% (8/40), 2.5% (1/40) vs. 22.5% (9/40) and 2.5% (1/40) vs. 20.0% (8/40), and there were statistical differences ( P<0.01 or <0.05); there was no severe hypotension, severe bradycardia and delirium in both groups. The overall satisfaction score in Q group was significantly higher than that in S group: (3.53 ± 0.63) scores vs. (2.70 ± 0.65) scores, and there was statistical difference ( P<0.01). Conclusions:Continuous micro-pump infusion of dexmedetomidine combined with oxycodone in AICU elderly patients with lung cancer after thoracoscopic radical surgery can significantly improve the quality of recovery and comfort during extubation, without affecting the extubation time, and can effectively reduce the degree of pain, stress and inflammatory reaction in the early recovery period, and reduce the incidence of adverse events after surgery.
6.Genetic damage in peripheral blood lymphocyte of coke oven workers.
Shu-guang LENG ; Yu-xin ZHENG ; Wen-zhong ZHANG ; Yu-fei DAI ; Yong NIU ; Ya-wen WANG ; Ye-ping GU ; Zu-fei PAN ; Jun XIAO ; Zhong-xu WANG ; Tao LI ; Feng-sheng HE
Chinese Journal of Industrial Hygiene and Occupational Diseases 2004;22(1):29-32
OBJECTIVETo investigate DNA and chromosome damage in peripheral blood lymphocyte of coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs).
METHODSOne hundred and thirty-seven coke oven workers and 50 controls without occupational PAHs exposure were investigated. Comet assay and cytokinesis-block micronucleus (CBMN) detection were used to evaluate DNA and chromosomal damage levels in peripheral blood lymphocyte. Urinary 1-hydroxypyrene level was used to assess the personal internal PAHs exposure dose. Personal information including occupational history, age, sex, smoking and drinking status was collected by questionnaire.
RESULTSUrinary 1-hydroxypyrene level in coke oven workers [(5.76 +/- 1.04) micro mol/mol Cr] was significantly higher than that in controls [(0.70 +/- 0.32) micro mol/mol Cr]. The rate of CBMN and comet tail moment of lymphocyte in coke oven workers [8.0 per thousand (0.0 per thousand - 30.0 per thousand ) and 2.09 (0.31 - 75.41), respectively] were higher than those in controls [3.5 per thousand (0.0 per thousand - 13.0 per thousand ) and 1.05 (0.11 - 6.63), P < 0.05]. In controls, the comet moment in smokers was significantly higher than that in non-smokers [1.44 (0.23 - 6.63) vs 0.81 (0.11 - 3.47), P < 0.05]. According to the length of work, 137 coke oven workers were classified into 3 groups i.e. 0.5 yrs , 16.0 yrs and 22.0 yrs group, and the comet moments were 1.34 (0.31 - 37.84), 2.32 (0.49 - 52.97) and 3.20 (0.45 - 75.41) respectively after adjusting the age, sex, smoking, drinking and level of urinary 1-hydroxy-pyrene. There was a rising tendency along with the increase in length of work.
CONCLUSIONUnder present PAHs exposure levels, both comet assay and Cytokinesis-block micronucleus test could detect PAHs-induced genotoxicity in coke oven workers, and comet assay is more suitable to assess the cumulative damage effect on DNA.
Adult ; Coke ; Comet Assay ; DNA Damage ; Female ; Humans ; Lymphocytes ; metabolism ; Male ; Middle Aged ; Occupational Exposure ; analysis ; Polycyclic Aromatic Hydrocarbons ; poisoning ; Pyrenes ; analysis ; Time Factors
7.A study on the inherited susceptibility of chromosomal damage in peripheral blood lymphocytes among coke oven workers.
Shu-guang LENG ; Yu-xin ZHENG ; Zu-fei PAN ; Yong NIU ; Yu-fei DAI ; Ya-wen WANG ; Wen-zhong ZHANG ; Jun XIAO ; Zhong-xu WANG ; Tao LI ; Feng-sheng HE
Chinese Journal of Preventive Medicine 2004;38(2):94-98
OBJECTIVETo investigate the association between polymorphisms of metabolic enzyme genes and chromosomal damage risk in peripheral blood lymphocytes among coke oven workers.
METHODSOne hundred and fourty-nine coke oven workers and 24 referents without occupational polycyclic aromatic hydrocarbons (PAH) exposure were recruited in this study. Urinary 1-hydroxypyrene levels were measured as the internal dose of PAH exposure. The 6 per 1 000 of micronucleus value was used as the cut-off value to determine whether the individual's chromosomal damage was positive. The genotypes of CYP1A1, GSTM1, GSTT1, GSTP1, CYP2E1, NQO1, NAT2 and mEH genes were determined by PCR-based methods. Multiple logistic regression was used to calculate the adjusted ORs and the 95% CI for the risk of chromosomal damage and to analyze the gene-gene interaction.
RESULTSIn 173 subjects, after adjusting the occupational exposure, age, sex, smoking and drinking status, the subjects with GSTM1 null genotype have significantly higher risk for chromosomal damage than subjects with GSTM1 positive genotype (adjusted OR = 2.01, 95% CI = 1.03 -3.91). Compared with the wild homozygotes at P187S site of NQO1 gene, the variant homozygotes have significantly higher risk for chromosomal damage (adjusted OR = 3.18, 95% CI = 1.18 - 8.62). The subjects with variant allele at H113Y site of mEH gene have significantly lower risk for chromosomal damage (adjusted OR = 0.40, 95% CI = 0.19 - 0.88). No significant associations were found for other gene polymorphisms and chromosomal damage risk. In addition, the gene-gene interactions were also found among GSTM1, NQO1 gene P187S and mEH gene H113Y polymorphisms for the risk of chromosomal damage risk.
CONCLUSIONSignificant associations between genetic polymorphisms in GSTM1, NQO1 and mEH gene and risk for chromosomal damage were found among occupational PAH-exposed workers, which related to the mechanism of PAH carcinogenesis.
Adult ; DNA Damage ; genetics ; Epoxide Hydrolases ; genetics ; Female ; Genetic Predisposition to Disease ; genetics ; Glutathione Transferase ; genetics ; Humans ; Logistic Models ; Lymphocytes ; metabolism ; Male ; Middle Aged ; Multivariate Analysis ; NAD(P)H Dehydrogenase (Quinone) ; genetics ; Occupational Exposure ; Polycyclic Aromatic Hydrocarbons ; poisoning ; Polymorphism, Genetic ; Pyrenes ; analysis ; Risk Factors
8.A study on the relationship between urinary 1-hydroxypyrene level and early genetic effect among coke oven workers.
Shu-Guang LENG ; Yu-Xin ZHENG ; Yu-Fei DAI ; Yong NIU ; Wen-Zhong ZHANG ; Ya-Wen WANG ; Xiao-Hua LI ; Zu-Fei PAN ; Jun XIAO ; Zhong-Xu WANG ; Tao LI ; Feng-Sheng HE
Chinese Journal of Preventive Medicine 2003;37(5):327-330
OBJECTIVETo investigate the relationship between the urinary 1-hydroxypyrene level and cytokinesis-block micronucleus and the olive moment of comet assay in peripheral blood lymphocyte in coke oven workers.
METHODSOne hundred and thirty-three workers from a coke plant and 28 referents without occupational PAH exposure were recruited in this study. Urinary level of 1-hydroxypyrene was measured by alkaline hydrolysis combined with high performance liquid chromatography as an internal exposure dose, and the DNA and chromosomal damage of peripheral blood lymphocyte were evaluated with comet assay and cytokinesis-block micronucleus method. Personal information including occupational history, age, sex, smoking and alcohol drinking, was collected by questionnaire.
RESULTSThere existed a good correlationship between the urinary level of 1-hydroxypyrene and frequency of micronuclei per 1 000 binucleated cells or the olive moment of comet assay in the study subjects, after adjusting for sex, age, smoking and alcohol drinking (r > 0.25, P < 0.01). One hundred and sixty-one subjects were divided into three groups by their urine 1-hydroxypyrene level (expressed as 0.30 - 2.44, 2.45 - 7.09 and 7.10 - 33.10 micro mol/mol Cr), and the geometric means of their urinary levels of 1-hydroxypyrene were 1.14, 4.32 and 12.49 micro mol/mol Cr, respectively. After adjusting for age, sex, smoking and alcohol drinking by multiple nonparametric analysis of covariance, the median of olive moment of comet assay in the group of 7.10 - 33.10 micro mol/mol Cr was 3.67, significantly higher than that in the groups of 0.30 - 2.44 and 2.45 - 7.09; and the micronuclei frequencies in the groups of 2.45 - 7.09 and 7.10 - 33.10 micro mol/mol Cr were 8.00 per thousand and 7.50 per thousand, respectively, significantly higher than that in the group of 0.30 - 2.44 micro mol/mol Cr (6.00 per thousand ).
CONCLUSIONSThe comet assay of peripheral blood lymphocyte was more suitable to detect the PAHs-induced early genotoxicity, than the cytokinesis-block micronucleus.
Adult ; Coke ; adverse effects ; Comet Assay ; Female ; Humans ; Male ; Micronuclei, Chromosome-Defective ; drug effects ; Micronucleus Tests ; Occupational Exposure ; adverse effects ; Pyrenes ; metabolism
9.Relationship of polycyclic aromatic hydrocarbon exposure with peripheral blood lymphocyte DNA damage in coke oven workers.
Shu-Guang LENG ; Yu-Xin ZHENG ; Yong NIU ; Ye-Ping GU ; Wen-Zhong ZHANG ; Yu-Fei DAI ; Ya-Wen WANG ; Xiao-Hua LI ; Zu-Fei PAN ; Jun XIAO ; Zhong-Xu WANG ; Tao LI ; Feng-Sheng HE
Chinese Journal of Industrial Hygiene and Occupational Diseases 2004;22(4):250-253
OBJECTIVETo investigate the relationship between lymphocyte DNA damage and polycyclic aromatic hydrocarbons (PAHs) exposure in coke oven workers.
METHODSTwo hundred and thirty-five coke oven workers and 30 controls were selected in this study. Alkaline single-cell gel electrophoresis was used to evaluate the lymphocyte DNA damage, HPLC was employed to measure 1-hydroxypyrene levels in spot urine samples which were obtained at the end of a workweek (4 days of 8 hours/day) and personal information including occupational exposure, age, sex, smoking and drinking status was collected by the questionnaire.
RESULTSThe lymphocyte DNA damage level expressed as olive moment in coke oven workers was significantly higher than that of controls [2.47 (0.22 approximately 46.68) vs 0.94 (0.42 approximately 4.21), P < 0.01], and correlation between urinary 1-hydroxypyrene concentrations and olive moment was found (Spearman Partial correlation coefficient = 0.22, P < 0.01) in coke oven workers. The 1.9 of olive moment value was used as the limit to determine whether the subject DNA damage was positive. The coke oven workers had significantly higher risk in DNA damage (adjusted OR = 5.38, 95% CI = 2.07 approximately 14.08) than did controls, and dose-response relationships were also found between external exposure (exposure category) or internal doses (urinary 1-hydroxypyrene) and DNA damage.
CONCLUSIONThere are dose-effect and dose-response relationships between PAHs exposure and lymphocyte DNA damage in coke oven workers.
Adult ; Animals ; Coke ; adverse effects ; DNA Damage ; drug effects ; Dose-Response Relationship, Drug ; Female ; Humans ; Lymphocytes ; metabolism ; Male ; Occupational Exposure ; Polycyclic Aromatic Hydrocarbons ; poisoning ; Pyrenes ; analysis ; metabolism ; Surveys and Questionnaires
10.Mutagen sensitivity in peripheral blood lymphocytes among coke-oven workers.
Juan CHENG ; Shu-guang LENG ; Hai-shan LI ; Yong NIU ; Yao-feng SUN ; Hua-wei DUAN ; Ping BIN ; Lin-yuan ZHANG ; Xue-miao LIANG ; Han LIN ; Zhong-xu WANG ; Yu-fei DAI ; Bin LI ; Yu-xin ZHENG
Chinese Journal of Preventive Medicine 2008;42(5):307-311
OBJECTIVETo investigate the sensitivity to bleomycin (BLM) in peripheral blood lymphocytes (PBL) among coke-oven workers.
METHODSNinty-four coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 64 non-coke-oven workers (control) were recruited into this study. PBL was challenged by 8 microg/ml BLM, a known carcinogen, to induce certain amount of DNA damage, the difference of olive tail moment (TM) measured by comet assay before and after BLM treatment reflected the sensitivity towards mutagens.
RESULTSThe distribution of age, sex, and prevalence of smoking and drinking were not significantly different between these two groups. The geometric mean of urinary 1-hydroxypyrene (1-OHP) was significantly higher in coke-oven workers than in controls (9.0 versus 1.5 microg/L, t = -9.317, P < 0.01). The coke-oven workers showed significantly higher sensitivity to BLM than controls (17.7 versus 14.9, t = -2.583, P = 0.01). A large inter-group difference in sensitivity to BLM was observed in both controls and coke-oven workers. Stratification analysis revealed the significant association between high 1-OHP level (> 9.0 microg/L) and increased sensitivity to BLM (F = 4.001, P = 0.05) among coke-oven workers. Smoking subjects showed a significant higher value of sensitivity than nonsmokers in controls but not in coke-oven workers. No significant difference was observed between age, drinking status, coking history or external exposure class and BLM sensitivity.
CONCLUSIONExposure to coke oven emission could increase the sensitivity to mutagens, which might be a reason of high incidence of lung cancer among coke-oven workers.
Adult ; Benzo(a)pyrene ; toxicity ; Bleomycin ; toxicity ; Coke ; Comet Assay ; DNA Damage ; DNA Repair ; Female ; Humans ; Lymphocytes ; drug effects ; Male ; Middle Aged ; Mutagens ; toxicity ; Occupational Exposure