International Journal of Environmental Research and Public Health Article Spatial and Temporal Distribution of Di-(2-ethylhexyl) Phthalate in Urban River Sediments Chih-Feng Chen 1, Yun-Ru Ju 1, Yee Cheng Lim 1, Jih-Hsing Chang 2, Chiu-Wen Chen 1,* and Cheng-Di Dong 1,* 1 Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan; [email protected] (C.-F.C.); [email protected] (Y.-R.J.); [email protected] (Y.C.L.) 2 Department of Environmental Engineering and Management, Chaoyang University of Technology, Taichung 41349, Taiwan; [email protected] * Correspondence: [email protected] (C.-W.C.); [email protected] (C.-D.C.); Tel.: +886-7-365-0884 (C.-W.C.); +886-7-365-0548 (C.-D.C.) Received: 29 August 2018; Accepted: 9 October 2018; Published: 11 October 2018 Abstract: This study investigated the spatial distribution of di-(2-ethylhexyl) phthalate (DEHP), and its potential biological effects, in the surface sediments that were collected from 10 sites at the Love River during dry and wet seasons. The grain size and organic matter were measured to understand the key factors that affect the distribution of DEHP concentrations in the sediments of Love River. The mean DEHP concentrations in the sediments that were collected during the wet and dry seasons were 28.6 ± 19.5 and 17.8 ± 11.6 mg/kg dry weight, respectively. The highest DEHP concentration was observed in the sediments that were sampled in the vicinity of the estuary. The correlation analysis showed that the grain size and organic matter may play a key role in the DEHP distribution in the sediments during the dry season, whereas the DEHP concentrations in the wet season may be mainly affected by other environmental and hydrological conditions. By a comparison with the sediment quality guidelines, the levels of DEHP in the sediments of Love River were found to have the potential to result in an adverse effect on aquatic benthic organisms. Specifically, during the wet season, wastewater from upstream of Love River is flushed downstream, causing a higher DEHP concentration in the sediments. Future pollution prevention and management objectives should move towards reducing the discharge of upstream wastewater and establishing a complete sewer system to reduce DEHP pollution in the environment. Keywords: di-(2-ethylhexyl) phthalate; DEHP; urban river; seasonal variation; sediments 1. Introduction Kaohsiung City is a highly industrialized city in southern Taiwan with a population of 2.8 million people. Southern Taiwan has a tropical climate; hence, Kaohsiung City has distinct dry and wet seasons [1]. The period from May to September is classified as the wet season, and its rainfall accounts for about 88% of the total annual rainfall [2]. Love River, one of the major rivers in Kaohsiung City, has a length of 16 km and a basin of 62 km2. From its main source near Tsao-Gong irrigation, the Love River flows through the downtown region of Kaohsiung City and eventually into Kaohsiung Harbor (Figure1). About 60% of the total population in Kaohsiung City lives in the regions along the Love River, which include numerous car wash factories, medical institutions, and construction sites. Moreover, the Love River is a canal that receives discharges from domestic, industrial, and farmland wastewater, resulting in an unstable water supply. About 15 drainage canals have been connected to the Love River from upstream to downstream. Since intercepting gates have been set up only in Int. J. Environ. Res. Public Health 2018, 15, 2228; doi:10.3390/ijerph15102228 www.mdpi.com/journal/ijerph Int. J. Environ. Res. Public Health 2018, 15, 2228 2 of 12 Int. J. Environ. Res. Public Health 2018, 15, x 2 of 12 the middle and lower reaches to block the wastewater from entering the drainage canals (Long-Hua Bridgethe drainage to Hou-Gang canals (L Bridge,ong-Hua Figure Bridge1), upstreamto Hou-Gang drainage Bridge canals, Figure are, 1), therefore,upstream drainage the major canals pollutant are, sourcestherefore [3]., the Eventually, major pollutant pollutants source deposits [3] and. Ev accumulateentually, pollutants in the sediments deposit and and mayaccumulate pose potential in the riskssediments to the localand may aquatic pose organisms. potential risks to the local aquatic organisms. 22°40.8’ Hou-Gang Bridge L1 Cai-Jin Bridge NN L2 Ding-Sin Bridge L3 600 0 600 Boa-Zhu-Gou 600 0 600 MMeterseters Interception Gate L4 Long-Hua Bridge L5 Sampling site Chi-Ping Bridge Interception Gate Long-Xin Bridge Barrier L6 Jin-Ru Bridge Chi-Ping Bridge River 22°38.7’ L7 Zhong-Du Bridge L8 Chien-Kuo Bridge L9 Chi-Hsiea Bridge Taiwan Chung-Cheng Bridge L10 Kaohsiung Bridge 22°36.5’ 120°12.7’ 120°16.4’ 120°20.0’ % FigureFigure 1.1. AA mapmap ofof thethe study area and the locations of the monitoring monitoring points. points. 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