Apigenin ameliorates petrol vapors-induced oxidative stress as occupational and environmental pollutants in rats: An in vivo study.

Petrol vapors as important occupational and environmental pollutants can cause oxidative stress and may play a role in the development of neurodegenerative diseases along with the risk factors involved. This research is designed as a preliminary study to evaluate the protective effects of apigenin (APG) on oxidative stress caused by petrol vapors inhalation in rats. A total of 24 male Wistar rats were randomly divided into four groups inside the inhalation chamber. Body weight changes and oxidative stress markers were investigated. The average body weight of the group exposed to petrol vapors was significantly lower compared to the other groups. The level of reactive oxygen species (ROS), content of oxidized-glutathione (GSSG), and Malondialdehyde were found to be higher in the petrol-inhaled group, while the content of reduced-glutathione (GSH) was lower compared to the other groups. APG administration did result in any significant improvement in these toxicities induced by petrol vapor. APG administration may ameliorate the petrol-induced oxidative stress. In chronic exposures, in addition to personal protection and engineering control, the use of compounds of natural origin may help in reducing the side effects (such as CNS) caused by exposure to petrol vapors.

The perchloroethylene-induced toxicity in dry cleaning workers lymphocytes through induction of oxidative stress.

Evaluation of the compounds and metabolites, and studying their side effects in the workplace is essential. This study was designed to evaluate the exposure of dry  cleaning workers to perchloroethylene (PEC), and its liver and kidney damage, and oxidative stress in B-lymphocytes isolated from the workers. Blood samples were evaluated for liver (alanine transaminase [ALT] and aspartate transaminase [AST]) and kidney (BUN and creatinine) markers. For measurement of PEC, exhaled, personal, and ambient air samples were collected and analyzed gas chromatography (GC-FID) through the NIOSH 1003 and 3704 methods. Also, the parameters of oxidative stress including the level of reactive oxygen species (ROS), glutathione (GSH), oxidized glutathione (GSSG), and lipid peroxidation (LPO) in B-lymphocytes were evaluated. The results showed that the levels of liver enzymes ALT and AST in dry cleaning workers are higher than in the control group. The personal exposure levels and exhaled air concentration of PEC in dry cleaning workers were above the recommended national occupational exposure limits (OELs) and the biological exposure index (BEI). The levels of ROS, LPO, and GSSG in B-lymphocytes from the dry cleaning workers are higher than the control group, and the levels of GSH in dry cleaning workers are lower. The results suggested that exposure of dry cleaning workers to PEC could be associated with liver damage and oxidative damage in B-lymphocytes.

The Past and Future Trends of Heat Stress Based On Wet Bulb Globe Temperature Index in Outdoor Environment of Tehran City, Iran.

BACKGROUND: The workers who are working in the open and warm environments are at risk of health effects of climate and heat changes. It is expected that the risk is increase with global warming. This study aimed to investigate the changes of Wet Bulb Globe Temperature (WBGT) index in the past and to predict their trend of future changes in Tehran, capital of Iran. METHODS: The meteorological data recorded in Tehran, Iran during the statistical period between 1961 and 2009 were obtained from the Iran Meteorological Organization and based on them, WBGT index was calculated and processed using Man-Kendall correlation test. RESULTS: The results of Man-Kendall correlation test showed that the trend of changes of annual mean WBGT during the statistical period under study (1961-2009) has been significantly increasing. In addition, the result of proposed predictive model estimated that an increase of about 1.55 degree in WBGT index will be seen over 40 years from 2009 to 2050 in Tehran. CONCLUSION: Climate change in Tehran has had an effect on person's exposure to heat stresses consistent with global warming.

Pulmonary functions of welders in gas transmission pipelines in Iran.

This study evaluated the influence of welding on pulmonary functions in welders. Spirometry tests were performed before and after work shift in 91 welders and 25 clerks (control group). We examined forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio and forced expiratory flow 25%-75% (FEF 25-75). Significant differences were found for FVC and FEV1/FVC between welders and the control group in pre- and post-shift measurements (p < .001). In welders, smoking and nonsmoking habit had no significant effects on any pulmonary indices before or after shift. Work experience and fume concentrations also had no significant effects on the majority of spirometric indices (p > .05). Most welders had at least 1 of the respiratory symptoms. Significant differences were found between pre- and post-shift indices (as percentage of predicted values calculated with spirometer) and between the welders engaged in some welding tasks and the control group before work shift. This study documented work-related changes in pulmonary functions in the welders and marked drops in these functions without symptoms in some welders.

Occupational exposure to manganese-containing welding fumes and pulmonary function indices among natural gas transmission pipeline welders.

OBJECTIVES: The objectives of this study were to evaluate manganese (Mn)-containing welding fumes' exposure, assess urinary Mn as a biomarker for Mn exposure and investigate the correlation of Mn in air, total fumes and urinary Mn with pulmonary function indices in 118 welders and 37 unexposed controls from two regions in Iran, Assaluyeh and Borujen. METHODS: Air samples were collected on mixed cellulose ester membrane filters in personal air samplers and then analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES) (NIOSH Method 7300). For all participants, urine samples were collected during the entire work shift, and Mn in urine was determined by graphite furnace atomic absorption spectroscopy according to NIOSH Method 8310. Spirometric measurements were also done for participants. RESULTS: The maximum exposures to airborne Mn and total fumes were 0.304 ± 0.256 mg/m(3) and 21.52 ± 9.40 mg/m(3), respectively. The urine Mn levels in the various groups ranged between 0.77 to 7.58 µg/l. The correlation between airborne Mn and urinary Mn was significant for total whole participants. Some values of spirometric indices were statistically lower in welders rather than controls. CONCLUSIONS: Our results indicate that many welders have been exposed to higher concentrations of Mn-containing welding fumes. Urinary Mn can be used as a biomarker for Mn exposure. There were weak inverse correlations between Mn-containing welding fumes and pulmonary function indices, and the inverse correlation between urinary Mn with forced vital capacities (FVC) and forced expiratory volume in 1 s (FEV1) was significant.