1Student, Department of Environmental Management, Science and research Branch, Islamic Azad University, Tehran, Iran, Email id: nsamohebbi@yahoo.com
2Department of Environmental Health engineering, School of Public Health, Tehran University of Medical Science, Tehran, Iran
3Department of Biodiversity, Science and research Branch, Islamic Azad University, Tehran, Iran
4HSEQ Advisor, Select Solutions, Sydney, Australi
Online published on 10 May, 2019.
Ecological risk assessment was performed on phosphor and nitrogen concentration of Sefidrood River and its tributaries to respond to concerns that swages entrances may be damaging aquatic ecosystems. Tier model were used to evaluate hazard quotient and risk classification to aquatic biota from pollutants and toxicity values were compiled for LC50 of 5 indicators. Results have shown while distance has increased from the discharge of untreated wastewater into the river, phosphorous concentration and risk factor also decreased. The amount of dissolved oxygen is inversely proportional to the concentration of phosphorus. Nitrogen has less linear relationship and it would be declined in distance, and then remain constant and then it gives ascending trend.
Screening Level, TIER, Discharge, Relationship, Risk Classification
