Survey on monthly variations of water quality in the Tajan River (Sari, Iran)

The aims of the study were to evaluate water quality of Tajan River in Sari in terms of chemical pollution and the impact of pollutant sources near the river by considering the climate, hydrological and hydraulic condition on it. In this study, 10 critical points of river were selected as sampling stations from dam to sea. Sampling was randomly done monthly from Apr 2009 to Mar 2010. Samples were analyzed in terms of chemical parameters after transferring to the laboratory according to standard methods. The results showed that the pH and temperature were within acceptable ranges of 6.5 to 8.5 and < 20°C, respectively. The minimum dissolved oxygen (DO) concentrations were above 6 mg/L along the river. Fish can survive because DO content was high. The maximum levels of biochemical oxygen demand (BOD), chemical oxygen demand (COD), phosphate (PO4) and nitrate (NO3) were at or below 30, 17, 0.5 and 0.7 mg/L, respectively. In general, the results showed that the physical and chemical qualities of water from Tajan River were within the acceptable limits for agricultural consumptions. In addition, Tajan River water can be classified in Class II.Keywords: Water quality, Tajan River, river pollution, water pollution.African Journal of Biotechnology Vol. 12(25), pp. 3984-399

Correlation between airborne manganese concentration at the workstations in the iron foundry and manganese concentration in workers’ blood

Background Manganese (Mn) used as raw material for melting process in the ferrous foundry is considered as hazardous neurotoxic substance because it accumulates in the central nervous system and may cause neurological disorders. The furnace-men and melting department workers are potentially exposed to manganese particles or fume in the workplace. The objective of the research has been to investigate the sources and levels of manganese exposure in the foundry by correlation of blood-manganese (B-Mn) and air-manganese (air-Mn) measurement. Material and Methods Air-Mn and Mn of blood serum were measured involving workers who worked in a big-sized foundry during 1 year. The standard method of the Occupational Safety and Health Administration (OSHA) ID-121 was used for air and blood assessment and atomic absorption spectroscopy (AAS) was carried out for air and blood sample analysis. Results The air sampling results have revealed that there is a high exposure to manganese (4.5 mg/m3) in the workplace as compared to the National Institute for Occupational Safety and Health’s (NIOSH) time weighted average (the reference time-weighted average (TWA) = 1 mg/m³). The average blood serum Mn concentration was 2.745 μg/l for subjects working for shorter than 3 months and 274.85 μg/l for subjects working 3–12 months. Conclusions Against the research hypothesis there was no correlation between the air-Mn concentration and the B-Mn (serum) level of manganese in the serum of the exposed subjects. It may be due to short time of air sampling of manganese airborne particles, and a real-time monitoring of airborne manganese particles is suggested for any future study. Med Pr 2017;68(4):449–45

Correlation between airborne manganese concentration at the workstations in the iron foundry and manganese concentration in workers’ blood

Background: Manganese (Mn) used as raw material for melting process in the ferrous foundry is considered as hazardous neurotoxic substance because it accumulates in the central nervous system and may cause neurological disorders. The furnace-men and melting department workers are potentially exposed to manganese particles or fume in the workplace. The objective of the research has been to investigate the sources and levels of manganese exposure in the foundry by correlation of blood-manganese (B-Mn) and air-manganese (air-Mn) measurement. Material and Methods: Air-Mn and Mn of blood serum were measured involving workers who worked in a big-sized foundry during 1 year. The standard method of the Occupational Safety and Health Administration (OSHA) ID-121 was used for air and blood assessment and atomic absorption spectroscopy (AAS) was carried out for air and blood sample analysis. Results: The air sampling results have revealed that there is a high exposure to manganese (4.5 mg/m3) in the workplace as compared to the National Institute for Occupational Safety and Health’s (NIOSH) time weighted average (the reference time-weighted average (TWA) = 1 mg/m3). The average blood serum Mn concentration was 2.745 μg/l for subjects working for shorter than 3 months and 274.85 μg/l for subjects working 3–12 months. Conclusions: Against the research hypothesis there was no correlation between the air-Mn concentration and the B-Mn (serum) level of manganese in the serum of the exposed subjects. It may be due to short time of air sampling of manganese airborne particles, and a real-time monitoring of airborne manganese particles is suggested for any future study. Med Pr 2017;68(4):449–45

Means and standard deviations of physicochemical characteristics, along with occurrence of mosquito species in different larval habitats in Mazandaran Province, May-December 2014.

<p>Means and standard deviations of physicochemical characteristics, along with occurrence of mosquito species in different larval habitats in Mazandaran Province, May-December 2014.</p

Composition of the mosquito larvae collected from eleven types of fixed larval habitats in Mazandaran Province, May- December 2014.

<p>Composition of the mosquito larvae collected from eleven types of fixed larval habitats in Mazandaran Province, May- December 2014.</p

Correlation coefficient between larval density and physicochemical properties of larval habitats adjusted by the habitats types in Mazandaran Province, August 2014.

<p>Correlation coefficient between larval density and physicochemical properties of larval habitats adjusted by the habitats types in Mazandaran Province, August 2014.</p

Distribution and number of mosquito larvae collected from fixed habitats in villages of Mazandaran Province, May- December 2014.

<p>Distribution and number of mosquito larvae collected from fixed habitats in villages of Mazandaran Province, May- December 2014.</p

A variety of fixed habitats of mosquito larvae in Mazandaran Province, 2014 (Original photo).

<p>A variety of fixed habitats of mosquito larvae in Mazandaran Province, 2014 (Original photo).</p

Coefficients of interspecific association (C₈) for larvae of different species in eleven types of fixed habitats in Mazandaran Province, May-December 2014.

<p>Coefficients of interspecific association (C₈) for larvae of different species in eleven types of fixed habitats in Mazandaran Province, May-December 2014.</p

Regression relationships between <i>Cx</i>. <i>pipiens</i> and EC, alkalinity, total hardness and chloride of larval habitats in Mazandaran Province, August 2014.

<p>Regression relationships between <i>Cx</i>. <i>pipiens</i> and EC, alkalinity, total hardness and chloride of larval habitats in Mazandaran Province, August 2014.</p