Effects of PM2.5 and NO2 on the 8-isoprostane and lung function indices of FVC and FEV1 in students of Ahvaz city,Iran

The aim of this study was to determine the correlation between PM_2.5 and NO₂ pollutants and oxidative stress marker (8-isoprostane) and lung function tests (FVC and FEV₁) in healthy children who were living and studying in three different areas of Ahvaz city including A₁: Naderi site with high traffic, A₂: Alavi Alley site with average traffic, and A₃: Ein 2 site with low traffic (a rural area on the suburb of Ahvaz). 30 students in the 12–13 year-old range were selected from each studied zone (1, 2 and 3 sites) during three months of year. Of each student, one sample was taken every two weeks to measure 8-isoprostane of exhaled breath condensate (EBC). Air pollution data were collected from three air quality monitoring stations. Also, the relationship between air pollution and 8-isoprostane as well as lung function tests were determined using generalized estimating equations (GEE). The mean concentration of PM_2.5 and NO₂ in A₁, A₂ and A₃ areas were 116, 92 and 45 (μg/m³) also 77, 53 and 14 (ppb) respectively. Among all studied students, there was a significant correlation between the increase of mean concentration of PM_2.5 and NO₂ in 1–4 before sampling day, increased 8-isoprostane concentration and decreased FEV₁, while there was no significant correlation between them and decreased FVC. In A₁ site, an increase in IQR (13 μg/m³) PM_2.5 and IQR (6.5 ppb) NO₂ on 1–4 days before sampling was associated with 0.38 unit (95% CI: 0.11, 0.65) and 1.1 unit (95% CI: 0.85, 1.35) increase in 8-isoprostane concentration, also decreased 121 ml and 190 ml FEV₁, respectively. Results showed that the short-term exposure to traffic-related air pollution can decrease the values of lung function indices and increase the oxidative stress. It may adversely affect children’s lungs.     

Evaluation of antioxidant bioindicators and growth responses in <Emphasis Type="Italic">Malva parviflora</Emphasis> L. exposed to cadmium

In this study, the effect of cadmium (Cd) uptake and concentration on some growth and biochemical responses were investigated in Malva parviflora under Cd treatments including 0, 10, 50 and 100 µM. The shoots and roots were able to accumulate Cd. However, increased Cd dose led to a considerable Cd content in the roots. Cd stress decreased growth, increased lipid peroxidation and also enhanced proline and ascorbic acid contents in both shoots and roots. Chlorophyll and carotenoid contents decreased in the plants with the increasing Cd concentration. While the activities of catalase (CAT) and superoxide dismutase (SOD) increased in the shoots under different Cd doses, these activities decreased in the roots as compared to the control. Both shoots and roots demonstrated a significant increase in guaiacol peroxidase activity in response to Cd stress. Contrary to the aboveground parts, the roots subjected to Cd doses showed a rise in protein content. Despite higher Cd content in the roots, it seems that CAT and SOD do not play a key role in detoxification of Cd-induced oxidative stress. These findings confirm that reduced biomass and growth under Cd stress can be due to an increase in oxidative stress and a decrease in photosynthetic pigment content. The present study clearly indicates that the shoots and roots exploit different tolerance behaviors to alleviate Cd-induced oxidative stress in M. parviflora.