Contents lists available at ScienceDirect Environment International journal homepage: www.elsevier.com/locate/envint Drivers of contaminant levels in surface water of China during 2000–2030: Relative importance for illustrative home and personal care product chemicals Ying Zhu a, ⁎ , Oliver R. Price b , John Kilgallon b , Yi Qi c , Shu Tao d , Kevin C. Jones a , Andrew J. Sweetman a, ⁎ a Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom b Safety and Environmental Assurance Centre, Unilever, Sharnbrook MK44 1LQ, United Kingdom c School of Architecture and Urban Planning, Nanjing University, Nanjing 210093, China d Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China ARTICLE INFO Editor: Martí Nadal Keywords: WWTPs GDP Urbanization rates Population Surface water concentration China ABSTRACT Water pollution are among the most critical problems in China and emerging contaminants in surface water have attracted rising attentions in recent years. There is great interest in China's future environmental quality as the national government has committed to a major action plan to improve surface water quality. This study presents methodologies to rank the importance of socioeconomic and environmental drivers to the chemical con- centration in surface water during 2000–2030. A case study is conducted on triclosan, a home and personal care product (HPCP) ingredient. Different economic and discharge flow scenarios are considered. Urbanization and wastewater treatment connection rates in rural and urban areas are collected or projected for 2000–2030 for counties across China. The estimated usage increases from ca. 86 to 340 t. However, emissions decreases from 76 to 52 t during 2000–2030 under a modelled Organisation for Economic Co-operation (OECD) economic scenario because of the urbanization, migration and development of wastewater treatment plants/facilities (WWTPs). The estimated national median concentration of triclosan ranges 1.5–8.2 ng/L during 2000–2030 for different sce- narios. It peaks in 2009 under the OECD and three of the Intergovernmental Panel on Climate Change (IPCC), A2, B1 and B2 economic scenarios, but in 2025 under A1 economic scenario. Population distribution and surface water discharge flow rates are ranked as the top two drivers to triclosan levels in surface water over the 30 years. The development of urban WWTPs was the most important driver during 2000–2010 and the development of rural works is projected to be the most important in 2011–2030. Projections suggest discharges of ingredients in HPCPs - controlled by economic growth - should be balanced by the major expenditure programme on waste- water treatment in China. 1. Introduction Water contamination can be harmful to human and ecosystem health. Emerging contaminants, such as pharmaceuticals, home and personal care products (HPCPs) have raised growing concerns (Boxall et al., 2012; EPA, 2017). Reducing untreated wastewater and protecting aquatic ecosystems are targets of the Sustainable Development Goals set by the United Nations to be reached by 2030 (Hering et al., 2016). China is a country with major challenges of water quality and avail- ability, including: the size and diversity of the country and its rivers; the population size and migration; rapid economic growth, with increased industrial, agricultural and domestic demands for usable water and the effluents that these activities generate. The Chinese Government therefore developed an ‘Action Plan for Water Pollution Prevention’ in mid-2015 (MEP, 2015a), which is laid out in the national 13th 5-Year Plan (CPGC, 2016). However, in order to make rational, effective and informed decisions which will improve water quality, there is an urgent need for a methodology to identify the potential key drivers to affect the level of contaminants in surface water, especially for those an- thropogenic-source contaninants. The results could improve and inform understanding, policy and decision-making. Socio-economic activities and environmental changes have affected water quality in China during the remarkable development over the past decades (Gleick, 2008–2009). Ingredients in HPCPs represent an https://doi.org/10.1016/j.envint.2018.03.013 Received 20 December 2017; Received in revised form 1 March 2018; Accepted 10 March 2018 ⁎ Corresponding authors. E-mail addresses: y.zhu6@lancaster.ac.uk, zhuyingpku@hotmail.com (Y. Zhu), a.sweetman@lancaster.ac.uk (A.J. Sweetman). Environment International 115 (2018) 161–169 0160-4120/ © 2018 Elsevier Ltd. All rights reserved. T