Application of multiple media pathway in health risk assessment of heavy metals in wastewater effluent — a case study in Yenshui River

Abstract

The development of industry not only brings economic benefit but also accompanies with environmental pollution issues such as the emission of industrial waste effluents Recently the multiple media pathway has been widely used in health risk assessment and it can estimate the distribution of chemical substances in food chain by alternative scenarios with different parameters Hence the purpose of this study is to establish a multiple media pathway for wastewater effluents in Tainan Yenshui River and analysis the uncertainties of health risk assessment In this study environmental and biological samples are analyzed to find the degree of pollution in Yenshui River MODFLOW and MT3DMS models are used to predict the metal distribution in groundwater after long-term pollution Multiple media pathway is established follow by human health risk assessment protocol (HHRAP) which is published by US EPA According to the simulation and assessment results non-carcinogenic risk in different scenarios are lower than the threshold for health hazard effects While simulation scenario refers to local irrigation water composition the highest contribution metals of hazard index (HI) are mercury (Hg) and lead (Pb) and the dose of Hg and Pb are mainly caused by river The sensitivity results indicate that the intake of plants is the key parameter to affect the risk assessment results follows by metal concentration of river or groundwater Thus local residents should reduce the use of river water to decrease the metal exposure

Date of Award	2019
Original language	English
Supervisor	Hsiu-Ling Chen (Supervisor)