Study of heavy metals in urban runoff

Abstract

A cross-sectional survey was conducted through Tehran city and a field study was conducted to prepare main an d accessory drainage chann els map. Three main drainage channels were identified for this research and some sampling stations were chosen. Three stations selected in south of Tehran. The reason for selecting th ese stations is that all urban surface runoff completely pass through these points and samples taken from these points are representative of all kinds of pollutants that transit from city surface. Another Three stations were selected in center and further three stations were selected at north of Tehran. Surface runoff flow in three main channels, from north to south of Tehran, converge at south of Rey city and finally end up to Ghom Salt lake. The stations were chosen at three trajectories, Sorkhe Hesar, Emad Avard, Kan. At each month two samples were prepared from nine different stations. After collection of samples with respect to standard methods, they were dissolved in nitric acid and then analyzed by atomic absorption device. The results show that the concentrations of pollutants increased from north to south. For instance, Zinc had most concentration with monthly average of 0.98 mg/l and Nickel had the lowest amount with 0.02 mg/l in southern stations. Average concentration of Zn, Pb, Cd, Cu and Ni were: 0.638, 0.097, 0.04 and 0.035 mg/l respectively. Total average concentrations of heavy metals at three main channels were of 0.177, 0.176 and 0.145 mg/l. Emad Avard was the most polluted chann el.

Assessment of Metals Concentration in Water, Sediment and Macrophyte Plant Collected from Lake Hawassa, Ethiopia

“…This is because variations in physicochemical values at different sites contribute for the variation of metal concentration. In line with our results, Igbinosa and Okoh [18] and Sekabira et al [35] reported that the concentration of metals in aquatic ecosystems are highly correlated with physico-chemical parameters as mentioned earlier by different authors. Agrochemical substances that runoff to those sites can cause variation in metal concentration.…”

“…The correlation for elemental pair such as Hg/Pb, Zn/Cd and Zn/ Pb in this study was consistent with the works of Kar et al [23] and Nirmal et al [24] and metal-physico-chemical pairs such as Cr/TDS and Zn/EC were also consistent to the work of Sekabira et al [35]. Particularly, the correlation of Zn with Pb and Cd in this study was agreed with the work of Okafor and Opuene [22].…”

Behaviour and fate of metals in urban wastewater treatment plants: a review

“…The WWTP is the central unit of the UWS, receiving the polluted wastewater coming from the urban area, originated from several sources as industrial sites, households/domestic (faeces and urine, food, amalgam, detergents, pipes and taps, drinking water, artist paint), (1000) and Zn (4000); limit value for As only applies in Denmark e Chromium was deleted from the regulation in 1995, and EPA is re-examining this limit business/commercial (car washes, dentists, large enterprises), hospitals (diagnostic agents, disinfectants, pharmaceuticals), pipe sediments and surface runoff from building materials (roofs and fronts), galvanized materials, traffic (brake linings, tires, asphalt wear, gasoline/oil leakages) and agricultural areas. As a significant part of the urban soil surfaces is impermeable, metals via atmospheric deposition will also be transported with storm water to WWTPs in combined sewage pipes, or directly to water recipients (Emmanuel et al 2005;Nabizadeh et al 2005;Sörme and Lagerkvist 2002;Bergbäck et al 2001;EC 2001a). Apparently, there is not a general consensus in the literature regarding the classification of these sources, as point or diffuse sources, probably because it depends on the referential that is being considered.…”

Modelling runoff quantity and quality in tropical urban catchments using Storm Water Management Model

“…There are now enough evidences to relate urban water deterioration to non-point sources pollution (e.g. Taebi and Droste 2004;Nabizadeh et al 2005;USEPA 2005;Atasoy et al 2006). Previous studies indicated that there were significant differences in stormwater constituents for different land use categories (Mcleod et al 2006;Pitt et al 2004;Al-Jaralla and Al-Fares 2009).…”