Climate change and human health in the Eastern Mediterranean and Middle East: Literature review, research priorities and policy suggestions.

Human health is linked to climatic factors in complex ways, and climate change can have profound direct and indirect impacts on the health status of any given region. Susceptibility to climate change is modulated by biological, ecological and socio-political factors such as age, gender, geographic location, socio-economic status, occupation, health status and housing conditions, among other. In the Eastern Mediterranean and Middle East (EMME), climatic factors known to affect human health include extreme heat, water shortages and air pollution. Furthermore, the epidemiology of vector-borne diseases (VBDs) and the health consequences of population displacement are also influenced by climate change in this region. To inform future policies for adaptation and mitigation measures, and based on an extensive review of the available knowledge, we recommend several research priorities for the region. These include the generation of more empirical evidence on exposure-response functions involving climate change and specific health outcomes, the development of appropriate methodologies to evaluate the physical and psychological effects of climate change on vulnerable populations, determining how climate change alters the ecological determinants of human health, improving our understanding of the effects of long-term exposure to heat stress and air pollution, and evaluating the interactions between adaptation and mitigation strategies. Because national boundaries do not limit most climate-related factors expected to impact human health, we propose that adaptation/mitigation policies must have a regional scope, and therefore require collaborative efforts among EMME nations. Policy suggestions include a decisive region-wide decarbonisation, the integration of environmentally driven morbidity and mortality data throughout the region, advancing the development and widespread use of affordable technologies for the production and management of drinking water by non-traditional means, the development of comprehensive strategies to improve the health status of displaced populations, and fostering regional networks for monitoring and controlling the spread of infectious diseases and disease vectors.

Lung cancer risk in workers occupationally exposed to polycyclic aromatic hydrocarbons with emphasis on the role of DNA repair gene.

OBJECTIVE: Workers in secondary aluminum production plants are occupationally exposed to polycyclic aromatic hydrocarbons (PAHs). We aimed to monitor the concentrations of PAHs in air and in serum of workers at two secondary aluminum production plants. We also investigated the potential risk of lung cancer development among PAHs exposed workers with emphasis on the role of A1AT mutation and APEX1 gene polymorphisms. METHODS: This study included 177 workers from administrative departments and production lines. Blood samples were obtained for estimation of benzo(a)pyrene diol epoxide albumin adduct (BPDE-Alb adduct), anti-Cyclin-B1 marker (CCNB1) and squamous cell carcinoma antigen (SCCAg). Genes' polymorphism for human apurinic/apyrimidinic endonuclease (APEX1) and alpha-1-anti-trypsin (A1AT) gene mutation were detected. RESULTS: There was a significant increase in the level of BPDE-Alb adduct among exposed workers in comparison to non-exposed group. Moreover, 41.67% of exposed workers in El Tebbin had BPDE-Alb adduct level ≥ 15 ng/ml versus 29.6% of workers in Helwan factory. There was a significant increase in tumor markers (SCCAg and CCNB1) among workers whose BPDE-Alb adduct ≥ 15 ng/ml. There was a significant increase in the level of BPDE-Alb adducts in exposed workers carrying homozygous APEX1 genotype Glu/Glu. Furthermore, exposed workers with the Glu/Glu genotype had high tumor markers levels. There was a significant increase in levels of BPDE-Alb adducts in workers carrying A1AT mutant allele. Moreover, workers with mutant A1AT genotype had significantly high tumor markers (SCCAg and CCNB1) levels. CONCLUSION: Therefore, we conclude that aluminum workers may be at a potential risk of lung cancer development due to PAHs exposure. Although PAHs concentrations in air were within the permissible limits, yet evidence of DNA damage was present as expressed by high BPDE-albumin adduct level in exposed workers. Also, elevation of tumor markers (SCCAg and CCNB1) in exposed workers points to the importance of periodic biological monitoring of such workers to protect them from cancer risk.

Influence of chitotriosidase gene polymorphisms on oxidative stress and susceptibility to Aspergillus infection among exposed workers.

Chitotriosidase (CHIT1) is involved in the innate defense against chitin-containing pathogens. In the present study, we sought to investigate the role of CHIT1 gene polymorphisms on susceptibility to Aspergillus infection in addition to oxidative stress caused by infection. CHIT1 gene polymorphisms were identified in 60 Aspergillus-positive workers by REFLP. We also measured concentrations of the CHIT1 enzyme, total antioxidant capacity (TAC), and malondialdehyde (MDA). The majority of workers were wild-type (AA) (66.5%), followed by heterozygous (AB) (28.5%), and homozygous mutants (BB) (5%). The mean concentrations of specific IgE for all Aspergillus species were affected by change in CHIT1 genotypes. Our findings indicate that decreased CHIT1 activity in homozygous mutant CHIT1 allele is associated with a subsequent decrease in TAC levels, resulting in an increased risk of fungal infection and accumulation of oxidant MDA. Thus, CHIT1 enzyme activity plays a critical role in the susceptibility of WWTP workers to fungal infections.

18S rRNA gene sequencing for environmental aflatoxigenic fungi and risk of hepatic carcinoma among exposed workers.

Aspergillus exposure causes an increase in aflatoxin (AF) levels among exposed workers thereby increasing their risk of developing hepatocellular carcinoma (HCC). This study attempted to determine the presence of airborne aflatoxigenic fungi in environment of waste water treatment plant (WWTP); and study the hepatic cancer risks among exposed workers, emphasizing the role of glutathione S-transferases (GST) gene polymorphism protecting against the risk of hepatic cancer development due to exposure to AFs. The study isolated and identified different Aspergillus species producing AFs in air samples from WWTP sites using 18S ribosomal ribonucleic acid (18S rRNA) gene sequencing technique. GST gene polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A significant increase in blood AF levels was found among WWTP exposed workers. The occurrence of GSTT1& M1 gene polymorphism in 6% of the workers was accompanied by significant decrease in the levels of AFs and alpha fetoprotein (AFP). In conclusion, Aspergillus-producing AFs were found in air of WWTP. Continuous exposure to AF-producing fungi caused elevated AF-levels in exposed workers. However only workers with heterozygous GSTT1& M1 genotypes can detoxify AFs, thereby decreasing the risk of HCC development among exposed workers.

Association between toxic organochlorine levels in human serum and systemic lupus erythematosus.

Organochlorines (OCs) are groups of highly toxic pesticides with known immunotoxicity. The present work aimed to study the potential association between serum residues of OCs and the risk of developing systemic lupus erythematosus (SLE) as well as correlating to the clinical-laboratory manifestations in a sample of Egyptian SLE patients. A cross-sectional study was conducted on 132 patients environmentally exposed to OCs. Patients were diagnosed as SLE based on the American College of Rheumatology (ACR) revised criteria. Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K) score was calculated to stratify the disease severity. Blood and urine samples were collected to measure the levels of OCs, serological markers, and urinary protein. The most frequently detected OCs were p,p'-DDE; lindane; and hexachlorobenzene (HCB). The risk of developing SLE was significantly associated with detected p,p'-DDE and HCB (B value 7.704 and 14.33, respectively). Hexachlorobenzene, in addition, was significantly associated with increased SLEDAI-2K score and polycythemia. Lindane was significantly associated with hypocomplementemia, cardiac manifestations of SLE, anemia, and leucopenia. In conclusion, the detected OCs p,p'-DDE and HCB are associated with increased risk of SLE in Egyptian patients and correlates to the manifestations of disease severity.

Association of genetic polymorphisms CYP2A6*2 rs1801272 and CYP2A6*9 rs28399433 with tobacco-induced lung Cancer: case-control study in an Egyptian population.

BACKGROUND: Several studies have reported the role of CYP2A6 genetic polymorphisms in smoking and lung cancer risk with some contradictory results in different populations. The purpose of the current study is to assess the contribution of the CYP2A6*2 rs1801272 and CYP2A6*9 rs28399433 gene polymorphisms and tobacco smoking in the risk of lung cancer in an Egyptian population. METHODS: A case-control study was conducted on 150 lung cancer cases and 150 controls. All subjects were subjected to blood sampling for Extraction of genomic DNA and Genotyping of the CYP2A6 gene SNPs (CYP2A6*2 (1799 T > A) rs1801272 and CYP2A6*9 (- 48 T > G) rs28399433 by Real time PCR. RESULTS: AC and CC genotypes were detected in CYP2A6*9; and AT genotype in CYP2A6*2. The frequency of CYP2A6*2 and CYP2A6*9 were 0.7% and 3.7% respectively in the studied Egyptian population. All cancer cases with slow metabolizer variants were NSCLC. Non-smokers represented 71.4% of the CYP2A6 variants. There was no statistical significant association between risk of lung cancer, smoking habits, heaviness of smoking and the different polymorphisms of CYP2A6 genotypes. CONCLUSION: The frequency of slow metabolizers CYP2A6*2 and CYP2A6*9 are poor in the studied Egyptian population. Our findings did not suggest any association between CYP2A6 genotypes and risk of lung cancer.

Effects of smoking on the oxidant/antioxidant balance and the blood lipids in pesticide sprayers.

The present study was conducted on 80 pesticide male sprayers (42 nonsmokers and 38 smokers). Our aim was to estimate the smoking effects on blood lipids and oxidant/antioxidant status in pesticide sprayers. Results revealed that cholesterol, low-density lipoprotein (LDL) and glutathion peroxidase (GPx) enzyme were significantly higher in the 38 smoker sprayers than in the 42 nonsmoker sprayers. Cholesterol and LDL were correlated with smoking index and high-density lipoprotein (HDL), superoxide dismutase (SOD) enzyme and zinc (Zn) were inversely correlated with duration of pesticides' exposure. In nonsmokers, LDL and cholesterol were negatively correlated with SOD and correlated with malondialdehyde (MDA), and cholesterol was negatively correlated with Zn. HDL was negatively correlated with MDA in all the sprayers, but was correlated with GPx in smokers and with Zn in nonsmokers. In smokers, LDL was negatively correlated with GPx, HDL was negatively correlated with MDA and triglycerides and very-low-density lipoprotein were negatively correlated with Zn. MDA was negatively correlated with SOD, GPx and Zn. Smoking and pesticide exposure could be responsible for hyperlipidemia and oxidative stress. Therefore, improvement in the antioxidant status is mandatory for pesticide sprayers especially the ones who smoke.

Carcinogenic effects of aflatoxin B1 among wheat handlers.

BACKGROUND: Epidemiological studies have demonstrated that serum aflatoxin B1 (AFB1) is a hepatocarcinogenic mycotoxin and contributor to the high rate of hepatocellular carcinoma (HCC). The prevalence of liver cancer in Egypt is particularly worrisome. In a registry-based analysis of occupational risk for HCC, significant excesses were observed especially for grain mill workers. OBJECTIVE: The aim of this study was to assess the hepatic carcinogenicity of AFB1 in wheat handlers. METHODS: Serum AFB1/albumin (AFB1/Alb), alpha-fetoprotein (AFP), alpha-l-fucosidase (AFU), and arginase were estimated in exposed wheat handlers including millers and bakers. The control group was composed of non-occupationally exposed workers. RESULTS: AFB1/Alb and AFU were significantly higher among workers employed as bakers compared to mill workers and controls. Mill workers had higher levels of AFB1/Alb than the controls. AFB1/Alb, AFP, and AFU were all significantly higher and arginase was significantly lower among HCC cases compared to the other groups. There was a significant correlation between AFU and AFB1/Alb in bakers and between AFP and AFB1/Alb in HCC cases. Arginase was inversely correlated with AFB1/Alb in HCC cases. AFB1/Alb was significantly correlated with the duration of exposure in bakers. CONCLUSION: Wheat handlers exposed to Aspergillus flavus have a high risk of elevated serum AFB1/Alb levels and AFU.

Bridging research-policy gaps: An integrated approach.

It is often difficult for policymakers to make informed decisions without evidence-based support, resulting in potentially ineffective policies. The purpose of this article is to advocate for collaboration and communication between researchers and policymakers to enhance evidence-based policymaking. The workshop hosted by the International Society of Environmental Epidemiology-Eastern Mediterranean Chapter further explores the challenges of connecting researchers and policymakers. The article highlights the gap between researchers and policymakers, attributed to different visions and objectives, time constraints, and communication issues. To strengthen the research-policy interface, strategies such as enhanced communication skills and early involvement of policymakers in research are suggested. The article proposes an integrated model combining the Collaborative Knowledge Model and the policy entrepreneurship mindset, emphasizing the co-creation of knowledge and evidence-based policy solutions. The use of this model can lead to the development of evidence-based policies that effectively address societal needs.

Effect of occupational exposure to aflatoxins on some liver tumor markers in textile workers.

BACKGROUND: In a study of textile workers, the effects of occupational exposure to cotton dust-with possible exposure to aflatoxin-on levels of some liver tumor biomarkers were explored. METHODS: The study included 58 textile workers and 64 controls. Skin prick tests, urinary Aflatoxin M1 (AFM1) and the tumor biomarkers (alpha-fetoprotein (AFP), alpha-L-fucosidase (AFU), insulin-like growth factors (IGF-1) were measured. RESULTS: Positive reactants to Aspergillus niger, Aspergillus flavus, and cotton dust were significantly higher in pre-spinning (14.3%, 28.6%, and 28.6%, respectively) and spinning workers (25.0%, 33.3%, and 25.0%, respectively) compared to controls (4.7%, 7.8%, and 3.1%, respectively). Urinary AFM1 was significantly higher in the pre-spinning, spinning, and weaving groups compared to controls (554.2 ± 346.2 pg/ml, 459.1 ± 781.6 pg/ml, 296.5 ± 336.5 pg/ml and 68.5 ± 136.8 pg/ml, respectively). We found a highly significant increase in levels of serum AFU in textile workers, compared to the control group. CONCLUSION: Exposure to fungi had a significant effect on AFM1 measurements and tumor biomarkers, especially in allergic textile workers (with the exception of the arginase biomarker), though results were generally within normal limits.

Organochlorine pesticide residues in biological compartments of healthy mothers.

The present study was conducted to detect placental and breast milk (BM) transfer of organochlorine pesticides (OCPs) between biological compartments in healthy lactating mothers. The study explores the effect of parity, breast-feeding and urban/rural residence on body burden of OCP residues. The study included 38 healthy participants submitted to cesarean delivery. Sociodemographic data and specimens of maternal and umbilical sera, adipose tissue (Adp T) and BM were collected. Specimens were analyzed to detect OCP residues. The lindane in BM, o,p'-dichlorodiphenyldichloroethane (DDD) in maternal serum (MS) and total dichlorodiphenyltrichloroethane (DDT) and o,p'-dichlorodiphenyldichloroethylene in umbilical serum were the only detected residues in significantly higher frequencies and/or means in the primigravidae than multigravidae. There was a high risk of detecting o,p'-DDD (odds ratio = 8.3) in umbilical serum of the mothers with o,p'-DDD detected in the MS. Total DDT was detected in about 65% of specimens of BM, MS and Adp T and in about 40% of the umbilical serum specimens. There was only a significant positive correlation between total DDT residues in the BM and Adp T. Total DDT residues in umbilical serum and Adp T were significantly higher in the urban than in the rural mothers. The detection of some OCPs in maternal biological compartments suggests their potential placental and BM transfer to her child during pregnancy and lactation, respectively. Furthermore, it might reflect the persistence or recent use of these pesticides in the environment.

Ventilatory functions in cotton textile workers and the role of some inflammatory cytokines.

Exposure to cotton dust in industrial environments causes inflammation in the airways of the exposed workers. This may manifest as respiratory complaints and changes in the respiratory functions after work shift and in the baseline of their ventilatory functions. The study aimed to investigate the effect of occupational exposure to cotton dust on respiratory symptoms, ventilatory functions and pro-inflammatory cytokine levels (tumor necrosis factor α, interleukin 6 and interleukin 1ß). The study was conducted on 63 textile workers and 65 nonexposed subjects. Both groups were matched for age, socioeconomic status and smoking habit. The respirable dust measured in the workplace did not exceed the permissible values of the Egyptian law 1994. The bacterial counts detected were within the occupational exposure limits of the industrial settings. The results revealed that the percentage of respiratory symptoms was higher in textile workers. Respiratory complaints were chronic cough (33.2%), chronic bronchitis (39.7%) and dyspnea (23.8%) in textile workers compared to (6.2%, 6.2% and 1.5%), respectively, in controls. There was a marked reduction in the ventilatory functions (forced vital capacity and forced expiratory volume in 1 s) in the textile workers compared to the controls. The additive effect of smoking on the ventilatory functions was not apparent. The ventilatory functions of the workers were significantly positively correlated with the duration of exposure. The cytokines were insignificantly higher in the textile workers compared to their controls. The textile workers with respiratory complaints showed significant decline in ventilatory functions and elevation in the cytokine levels compared to the nonsymtomatizing workers with significant difference in interleukin 1ß and interleukin 6. In conclusion, the results supported the fact that exposure to cotton dust deteriorates ventilatory functions and elevates proinflammatory cytokine levels. Analysis of the release of cytokines can be used to evaluate the immune responses to organic dust-induced airway inflammation.

Role of MTHFR 677C>T and 1298A>C gene polymorphisms on renal toxicity caused by lead exposure in wastewater treatment plant workers.

Environmental and occupational lead (Pb) exposures continue to pose major public health problems. Wastewater treatment plant (WWTP) workers proved are exposing to high Pb concentrations in sludge departments. The aim of the work was to investigate the role of MTHFR C677T and MTHFR A1298C gene polymorphisms on alteration of oxidative stress and homocysteine levels in WWTP workers exposed to high Pb concentrations, and study its relations with renal functions. The study included 90 WWTP workers from Abu-Rawash WWTP. Homocysteine, creatinine, urea, malondialdehyde (MDA), and total antioxidant capacity (TAC) were measured. Polymorphisms of MTHFR C677CT and MTHFR A1298C genes were studied using PCR/RFLP. Urine Pb concentrations were also measured. About 32.2% of the workers were with detectable Pb levels. Pb, homocysteine, and MDA levels were significantly higher among workers carrying TT polymorphism compared to other MTHFR C677T gene polymorphisms, while TAC was significantly lower among them compared to other polymorphisms. The same results were found among workers carrying CC compared to other MTHFR A1298C gene polymorphisms. WWTP workers carrying MTHFR 677TT and MTHFR 1298CC are more susceptible to elevation of homocysteine and the urinary Pb compared to the workers with the other polymorphisms. Furthermore, those workers were found to have increase in urea and creatinine. Therefore, MTHFR C677T and MTHFR A1298C gene polymorphisms could be used for prediction of the susceptibility to the risk of kidney impairments among WWTP workers in the sludge departments caused by their exposure to high Pb in their workplace.

Temporal trend of diarrhea morbidity rate with climate change: Egypt as a case study.

Many studies have detected a relationship between diarrhea morbidity rates with the changes in precipitation, temperature, floods, droughts, water shortage, etc. But, most of the authors were cautious in their studies, because of the lack of empirical climate-health data and there were large uncertainties in the future projections. The study aimed to refine the link between the morbidity rates of diarrhea in some Egyptian governorates representative of the three Egyptian geographical divisions with the meteorological changes that occurred in the 2006-2016 period for which the medical data are available, as a case study. Medical raw data was collected from the Information Centre Department of the Egyptian Ministry of Health and Population. The meteorological data of temperature and precipitation extremes were defined as data outside the 10th-90th percentile range of values of the period of study, and their analysis was done using a methodology similar to the one recommended by the WMO and integrated in the CLIMDEX software. Relationships between the morbidity rates of diarrhea in seven Egyptian governorates and the meteorological changes that occurred in the period 2006 to 2016 were analyzed using multiple linear regression analysis to identify the most effective meteorological factor that affects the trend of morbidity rate of diarrhea in each governorate. Statistical analysis revealed that some meteorological parameters can be used as predictors for morbidity rates of diarrhea in Cairo, Alexandria, and Gharbia, but not in Aswan, Behaira, and Dakahlia where the temporal evolution cannot be related with meteorology. In Red Sea, there was no temporal trend and no significant relationships between the diarrhea morbidity rate and meteorological parameters. The predictor meteorological parameters for morbidity rates of diarrhea were found to be depending on the geographic locations and infrastructures in these governorates. It was concluded that the meteorological data that can be used as predictors for the morbidity rate of diarrhea is depending on the geographical location and infrastructures of the target location. The socioeconomic levels as well as the infrastructures in the governorate must be considered confounders in future studies.

Aspergillus hazardous problem in ceramic workers.

Ceramic workers are at a high risk of developing respiratory problems as they are exposed to high levels of respirable dust containing silica and high microbial counts, including high Aspergillus counts. The aim of the study was to study the percentage of ceramic workers with positive Aspergillus (A.) through polymerase chain reaction (PCR) and specific IgE (sIgE) for the different Aspergillus species. PCR and specific IgE (sIgE) for the different Aspergillus species (A. flavus, A. fumigatus and A. niger) were estimated in 40 ceramic workers and 56 control subjects. Results revealed that 32.5% of the workers' sputum was PCR positive for Aspergillus. About 69.2% of them were A. flavus positive, 15.4% A. niger positive, 7.7% A. fumigatus positive and 7.7% A. flavus and A. fumigatus positive. The percentage change in sIgE for A. fumigatus between the workers and their controls was over 100%, while less than 50% for the other two species. The sIgE levels for the three Aspergillus species were not significantly correlated with the duration of exposure. Fungal exposure could be considered potential hazardous problem in ceramic industry. There were no significant correlations between the duration of exposure and the sIgE for the different Aspergillus species.

Role of Climate Change in Changing Hepatic Health Maps.

PURPOSE OF REVIEW: Climate change (CC) is currently responsible for global weather extremes. These weather extremes could contribute to changes in the pattern of health problems. The purpose of this review is to discuss the role of CC on remapping of hepatic diseases and the mechanisms of re-mapping. RECENT FINDINGS: CC was found to have a major influence on the distribution and severity of hepatic diseases, such as outbreaks of vector-borne, water or food-borne, parasitic diseases, re-emerging of disappeared diseases, or emerging of new forms of infectious agents. Migration of infected people from endemic areas due to the CC disasters results in rapid dissemination of infectious diseases that leads to outbreaks or endemicity of diseases in new areas. CC could cause increasing chemical emissions, or change in its biodegradability, or restriction in its dispersion, such as PM, PAHs, heavy metals, mycotoxins, and aquatic toxins. Increase in the concentrations of these chemicals may have significant impacts in changing the health map of hepatic toxicity and liver cancer. The current review confirms the role of CC in changing the pattern of several liver health problems and remapping of these problems in several regions of the world. This review could be of high importance to the health decision-makers as an early alarm and prediction of hepatic health problems with the projected CC.

Impact of mannose-binding lectin gene polymorphism on lung functions among workers exposed to airborne Aspergillus in a wastewater treatment plant in Egypt.

In this study, the risk of Aspergillus (Asp.) positivity and its respiratory health impacts on wastewater treatment plant (WWTP) workers were studied. In addition, it identified the geno-susceptibility role of mannose-binding lectin 2 (MBL2) gene polymorphisms and the mannose-binding lectin (MBL) serum levels on the pulmonary functions of the Asp.-positive workers. Pulmonary function tests (PFTs) were performed for 89 workers from a selected WWTP, after exclusion of the smokers. Molecular identification of Asp. blood positivity was done by 18S rRNA sequencing. Determination of MBL2 gene polymorphism and estimation of MBL serum levels were done. PFTs revealed abnormalities in 49.2% of the workers. Asp. was positive in 42.5% of the workers with different species. Among the Asp.-positive workers, 6.5% of the workers were with obstructive PFTs, 12.9% with restriction, and 22.6% with combined PFT abnormalities. MBL2 genotyping showed that wild genotype AA was common (68.5%) among Asp.-positive workers compared to the other genotypes. This allele, whether homozygous or heterozygous, was significantly associated with decline in PFTs of the exposed workers. MBL serum levels were significantly lower in workers with obstructive, restrictive, and combined PFT abnormalities compared to those with normal PFTs, and in the workers with Asp.-positive species than the Asp.-negative workers. Moreover, it was significantly lower in workers with Asp. fumigatus compared to that in the workers with other Asp. species, and in the Asp.-positive workers with homozygous or heterozygous A allele compared to that in the Asp.-positive workers with homozygous B allele. Working in a WWTP can be associated with impaired PFTs due to exposure to airborne fungi. MBL2 genotyping showed that Asp.-positive workers with homozygous or heterozygous A allele were at risk to develop decline in their PFTs.

Influence of GSTM1, T1 genes polymorphisms on oxidative stress and liver enzymes in rural and urban pesticides-exposed workers.

Several studies discussed the relationship between the toxicity of organophosphates (OPs) and carbamates pesticides and oxidative stress which affects human health. This study aimed to evaluate the effects of pesticides on the induction of oxidative stress and hepatotoxicity. It was also focused on glutathione-S-transferase gene polymorphism in the modulation of these effects. In addition, the role of the educational level of exposed workers was studied. Acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), liver enzymes, malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), and glutathione S transferase (GST) were estimated at 100 pesticide-exposed workers (50 urban researchers (UE) and 50 rural sprayers (RE)), and 100 matched controls (50 urban controls (UC)and 50 rural controls (RC)). AChE and BuChE were decreased in RE and UE compared to RC. Aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activity were elevated in UE and UC compared to the RE and RC. Alanine aminotransferase (ALT) was elevated in UE compared to RE. MDA in RE and UE showed elevation compared to RC. There was a significant reduction in the levels of GSH, GST, and GPx in UE compared to RE and RC. The most sensitive pesticide-induced hepatotoxicity group were exposed workers with the GSTT1 genotype. Within these workers, ALT and ALP were significantly correlated with MDA and inversely correlated with AChE and BuChE, while AST was inversely correlated with AChE and BuChE only in UE. Conclusion: GST gene polymorphisms appeared to have a significant role in workers' susceptibility to hepatotoxic effects due to occupational exposure to pesticides; GSTT1 was the most sensitive genotype.

Thyroid functions in paints production workers and the mechanism of oxidative-antioxidants status.

Assessment of occupational exposure to paints production chemicals mainly organic solvents in production of thyroid dysfunction and the mechanism of oxidative-antioxidant imbalance. Triiodothyronine (T(3)), thyroxine (T(4)), malondialdehyde (MDA), nitric oxide (NO) and total antioxidants was measured in 36 workers and 40 controls. T(3) and T(4) were elevated in 18.8% and 44.4% of the workers, respectively. T(3), T(4), MDA and NO levels were significantly higher in workers compared to controls. Total antioxidants was significantly lower in workers than in controls. T(3) and T(4) were significantly correlated with duration of exposure, while, total antioxidants was inversely correlated. In workers, T(3) was significantly correlated with MDA and inversely correlated with total antioxidants levels. MDA and NO were significantly higher in workers with abnormal T( 4) than normal workers. Workers exposed to organic solvents proved to be at risk for hyperthyroidism. Oxidative-antioxidant imbalance was found to have a significant role in development of hyperthyroidism with increasing duration of exposure.

Association of microsomal epoxide hydrolase gene (fast genotype) with lung functions impairment in wood workers.

OBJECTIVES: Exposure to wood dust may lead to impairment of the lung functions. Microsomal epoxide hydrolase enzyme (EPHX1) was shown to take part in protection against oxidative stress. An alteration in enzyme activity might be associated with its gene polymorphisms. In vitro polymorphisms in exons 3 (His113Tyr) and 4 (Arg139His) lead to reduced activity (slow allele) and increased activity (fast allele). Macrophage inflammatory protein 2 (MIP-2) is produced in rat lung epithelial cells after exposure to fine particles. We aimed to investigate the associations between mEPHX1 polymorphisms (in exon 3 and 4) and lung function in furniture workers and assessment of MIP-2 effect. METHODS: Our study was performed on 70 wood dust exposed male workers and 70 matched normal controls subjects. Ventilatory function tests were measured by spirometer, MIP-2 was performed by ELISA methods and EPHX gene was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods for each participant. RESULTS: Significant reduction in forced vital capacity (FVC%) and forced expiratory volume in the first second (FEV1) levels in Tyr-Tyr and Tyr-Hist genotypes of EPHX (exon 3) was observed. Reduced peak expiratory flow (PEF) levels and significant rise in MIP-2 levels were detected in Tyr-Tyr genotype. While high significant reduction in FVC% and FEV1 levels were shown in different genotypes in exon 4. Significant rise was observed in MIP-2 levels in Hist-Hist genotype of exon 4. An increase in duration of exposure showed positive correlation with fall in ventilatory functions. CONCLUSIONS: It was concluded that in Hist139Arg of EPHX gene, fast genotype (Arg-Arg) was associated with impaired ventilatory functions.