JWSS - Journal of Water and Soil Science

Long- term exposure to street dust because of the potential toxicity of heavy metals can cause harmful effects on the human's health by inhalation, ingestion and dermal contact. In this study, 25 dust samples were collected from the sidewalks of the main streets of Ilam and analyzed by inductively coupled spectroscopy (ICP- OES) method. The mean concentration of the studied metals was: Pb (58.80), Zn (213.24), Cu (63.12), Cr (45.84), Cd (0.37), Ni (43.73) V (30.92) and As (5.00) (mg / kg). Based on the average value of the potential ecological risk (Er), the heavy metals of Pb, Zn, Cu, Cr, Ni and V had a low ecological risk and Cd showed a moderate one. The highest non- carcinogenic risk (HQ) in children and adults was related to As through ingestion and Cr through the dermal contact pathway; on the other hand, the lowest amount was due to the Cd via the inhalation. Cumulative non- carcinogenic hazard (HI) of all heavy metals in the street dust have been found to be higher for children rather than adults. In both age groups, Cr and Pb had the highest and lowest risk of carcinogenicity (RI), respectively. The obtained results, therefore, indicate that the main source of heavy metals in the study area is anthropogenic sources such as traffic, industrial facilities and fossil fuels burning.

In the past years, by increasing population and water consumption, as well as the high cost of developing surface water resources, the exploitation of groundwater resources has increased significantly. In the current situation, a significant part of the country's water consumption in all sectors of consumption is provided by groundwater sources. On the other hand, the development of industry and the entry of pollutants, including heavy metals, into the groundwater endanger the health of humans. The present research has investigated the non-cancerous risk caused by heavy metals in the groundwater of Urmia plain for both children and adults. This research is based on a descriptive-analytical method based on the available data, in which the concentration of polluting metals obtained from the studies conducted in the fall and winter of 2016 from the number of 12 wells supplying rural drinking water in the Urmia plain has been analyzed. Also, human health risk assessment was measured using the United States Environmental Protection Agency index. The results showed that there are six heavy metals including cadmium, copper, iron, manganese, nickel, and lead in the region's groundwater, among which two of the wells have cadmium and lead values higher than national and international standards. Also, the total non-cancer risk index through ingestion and skin absorption for both children and adults groups was found to be 0.23 and 0.096, respectively, which is less than one, and this indicates that the water quality of the region is suitable for drinking.