Hepatotoxicity of aflatoxin B1 and its oxidative effects in wood dust Egyptian exposed workers.

The goal of the present study is to estimate the oxidative effects of AFB1 induced hepatotoxicity in furniture wood dust exposed workers. A cross-sectional comparative study was designed for comparing AFB1/albumin (AFB1/alb) levels and liver functions [alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP)], malondialdehyde (MDA), glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) in 88 furniture workers and 78 controls not occupationally exposed to wood dust. The AFB1/Alb, AST, ALT, MDA, and GPx were significantly higher; while, CAT significantly reduced in workers compared with controls. There was a significant correlation between AFB1/Alb and MDA level with the liver enzymes among both groups. CAT was inversely correlated with AFB1/Alb and the liver enzymes, and GPx was inversely correlated with AST in the workers. It was concluded that wood dust exposure is associated with raised serum levels of AFB1 and oxidative stress.

Early prediction of liver carcinogenicity due to occupational exposure to pesticides.

Several studies linked between pesticides exposure and development of liver cancer, through several mechanisms inform of genotoxicity, cytotoxicity, tumor promotion, immunotoxicity and hormonal actions. This study aimed to estimate novel biomarkers for early prediction of liver malignancy due to occupational exposure to pesticides in two groups of workers with different socioeconomic standard (highly educated urban researchers and low educated rural pesticides sprayers). This study included 50 urban researchers and 50 rural pesticides sprayers occupationally exposed to pesticides. They were compared with 50 non-exposed urban researchers and 50 non-exposed rural subjects. Several tumor biomarkers were estimated; P53 protein, Alfa fetoprotein (AFP), and Alpha-L-fucosidase (AFU). Additionally, telomerase enzyme activity, Relative telomere length (RTL), and DNA damage using comet assay were measured. Furthermore, the glutathione-S-Transferase (GST) gene polymorphisms were identified for both exposed groups. Statistical analysis revealed elevated level of tumor biomarkers among exposed subjects relative to control groups in spite of being within the normal range. Increase in the DNA damage was detected, with shortening of telomere length and decrease in telomerase enzyme activity in pesticides-exposed subjects compared to their controls. Most of these changes were related to the levels of butyrylcholinesterase. Subjects with GSTT1 genotype were suggested to be more susceptible to hepatic carcinogenicity. Telomere relative length and comets assay together with GST genes polymorphisms could be used as early predictors for liver cancer susceptibility among pesticides exposed workers.

Effect of Occupational Cadmium Exposure on Parathyroid Gland.

BACKGROUND: Cadmium (Cd) is used in many industries. High-level exposure is associated with severe kidney and bone damage. AIM: This study investigates the possible effect of occupational cadmium exposure on parathyroid gland and some minerals in workers. METHODS: Environmental air monitoring of cadmium was done. Serum and urine cadmium levels, kidney function, some minerals, and plasma parathormone were estimated in the studied groups. RESULTS: The exposed workers had significantly higher Cd concentration in serum and urine than controls. The mean levels of plasma parathyroid hormone, serum phosphorus and magnesium were significantly lower among the exposed group. However, the mean levels of serum creatinine and calcium were significantly higher in the same group when compared to referents. There was a significant positive correlation between Cd concentration in the serum and urine for the exposed group. The biological Cd exposure indices correlated positively with serum calcium and negatively with plasma PTH level. The prevalence of musculoskeletal complaints, bone ache, joint pain and muscle spasm were more prevalent among the exposed workers compared with the controls with odds ratio 4.316, 3.053 and 3.103 respectively. CONCLUSIONS: Occupational cadmium exposure has an adverse effect on PTH level and serum human minerals.

Hormonal Perturbations in Occupationally Exposed Nickel Workers.

BACKGROUND: Nickel exposure is recognized as an endocrine disruptor because of its adverse effects on reproduction. AIM: This study was designed to investigate the possible testiculo-hormonal perturbations on workers occupationally exposed to nickel and to assess its effects on human male sexual function. METHODS: Cross-sectional comparative study, comprising 105 electroplating male non-smoker, non-alcoholic workers exposed to soluble nickel and 60 controls was done. Serum luteinizing hormone, follicle stimulating hormone, testosterone levels and urinary nickel concentrations were determined for the studied groups. RESULTS: Serum luteinizing hormone, follicle stimulating hormone, urinary nickel and the simultaneous incidence of more than one sexual disorder were significantly higher in the exposed workers compared to controls. The occurrence of various types of sexual disorders (decreased libido, impotence and premature ejaculation) in the exposed workers was 9.5, 5.1 and 4.4 folds respectively than the controls. CONCLUSIONS: Exposure to nickel produces possible testiculo-hormonal perturbations in those exposed workers.

Comparative Hepatotoxicity of Aflatoxin B1 among Workers Exposed to Different Organic Dust with Emphasis on Polymorphism Role of Glutathione S-Transferase Gene.

AIM: The study aimed to investigate effects of organic dust exposure from different sources on aflatoxin B1-albumin adducts (AFB1/Alb), and role of glutathione S-transferase (GST) gene polymorphism in hepatotoxicity of (AFB1) among exposed workers. MATERIAL AND METHODS: Liver enzymes, AFB1/Alb, and GST polymorphism were estimated in 132 wheat flour dust and 87 woods sawmill workers, and 156 controls. RESULTS: Results revealed that AFB1/Alb and liver enzymes were significantly elevated in exposed workers compared to controls, and were significantly higher in sawmill workers compared to flour workers. AFB1/Alb in flour and sawmill workers with GSTT1 and GSTM1&GSTT1 null genotypes were significantly higher than controls, and in sawmill workers with GSTM1&GSTT1 null than flour workers. Liver enzymes (ALT and AST) in sawmill workers were significantly higher than flour workers and controls in all GST polymorphism; except in GSTT1 polymorphism, where these enzymes were significantly higher in the two exposed groups than controls. CONCLUSIONS: In conclusion, organic dust exposure may cause elevation in AFB1/Alb and liver enzymes of exposed workers, and GST gene polymorphism plays an important role in susceptibility to hepatic parenchymal cell injury; except in workers with GSTT1&GSTM1 null genotype, gene susceptibility seemed to have little role and the main role was for environmental exposures.

Serum autoantibodies in silicosis and non-silicosis cement workers.

AIM: To study serum autoantibodies and immunoglobulin levels in cement workers. METHODS: Blood samples for numerous antibodies were collected from 30 silicosis and 42 non-silicosis cement workers. Spirometry of the silicosis workers was also studied. RESULTS: Serum IgA mean level showed a significant increase in the silicosis group compared to the non-silicosis group. Elevated titers of serum anti-smooth muscle antibodies (ASMA) and anti-glomerular basement membrane (anti-GBM) were detected only in the silicosis group. The duration of exposure showed a significant positive correlation with serum IgA, ASMA and anti-GBM, and a significant negative correlation with serum IgG. Serum anti-GBM showed a significant positive correlation with IgG while the inverse titer (1/titer) of anti-GBM showed highly significant positive correlations with serum IgA and ASMA. The percent predicted FVC was the ventilatory function most closely associated with immunological parameters in silicosis group. CONCLUSION: Serum IgA, ASMA, and anti-GBM are the principal immunologic parameters associated with silicosis.

Serum Levels of Copper, Ceruloplasmin and Angiotensin Converting Enzyme among Silicotic and Non-Silicotic Workers.

BACKGROUND: Silicosis is the most frequently occurring pneumoconiosis. AIM: Measurement of serum levels of Angiotensin converting enzyme (ACE), Copper (Cu) and Ceruloplasmin (Cp) in cement workers occupationally exposed to silica dust as biomarkers of exposure rather than biomarkers of effect for silicosis. METHODS: Plain chest X-ray & pulmonary functions were done for 30 silicotic and 42 non-silicotic workers and 42 controls. CT scan was done for the exposed groups. Serum levels of Cu, Cp and ACE were estimated. RESULTS: The results showed a higher significant difference between the exposed groups and controls, and between the two exposed groups regarding the mean levels of all measured biochemical parameters. The pulmonary functions were significantly lower among silicotic workers than controls and non-silicotic groups. There was a significant positive correlation between duration of employment and serum ACE and Cu. CONCLUSION: Since respirable dust exposure-linked lung fibrosis disease is non-curable, the biochemical parameters (Cu, ACE and Cp) can be used as exposure biomarkers to silica dust, providing a better way for early diagnosis of this deadly disease. Down regulating the inflammatory responses could potentially reduce the adverse clinical pulmonary effects of air pollution.

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.