Correspondence Chinese landfill collapse: urban waste and human health At least 69 people were killed and eight others were missing after a landslide in Shenzhen, north of Hong Kong, on Dec 20, 2015.1 Unlike most landslides triggered by high-intensity rainfall or earthquakes, this disaster was manmade and triggered by the collapse of a construction waste disposal site. This landslide highlights the health implications of both disaster resilience and waste management during rapid urbanisation in developing countries. From 2000 to 2015, more than 3400 people were killed and over 2 million were otherwise affected by landslides in China.2 The immediate injuries included blunt trauma, crushing, asphyxiation, and drowning.3 Victims are more likely to have mental disorders, including post-traumatic stress disorder, panic attacks, or major depressive episodes. After the landslide in Shenzhen, more than 300 medical workers and 50 mental health professionals were actively involved in the disaster relief and recovery work, but the long-term mortality, morbidity, and mental health implications are still unknown. This disaster was caused by the collapse of a large pile of construction and demolition waste. Soil and aggregates are usually not directly toxic, but asbestos, polychlorinated biphenyls, brominated flame retardants, and heavy metals are often produced and released during construction and demolition work, especially in improperly managed brownfield sites. Dust and particulate matter, such as PM2·5, are generated by waste transportation and dumping. Toxic leachates, particularly heavy metals, and methane from landfills are major challenges for the environment and for human health. In addition to formal waste collection and recycling systems, 3·3–5·6 million people are involved in informal waste www.thelancet.com/lancetgh Vol 4 July 2016 collection and are responsible for recycling 17–38% of urban solid waste in China.4 Unfortunately, the informal sector is usually unaware or has little consideration of occupational health and safety. Several classes of disease have been identified as especially prevalent among waste pickers—eg, diarrhoea, malaria, cholera, hepatitis B, and pneumonia.5 A range of cancers are occupational hazards for many informal collectors. To avoid similar landslides, the fundamental solution is to reduce waste volume. Additionally, monitoring, reusing, recycling, and recovering waste should be more widely conducted. Globally, about 15 million people are involved in informal waste recycling.6 To alleviate the hazards faced by those involved in this sector, cooperatives and associations of informal recyclers have been created in Latin America.6 In China, new initiatives are needed to integrate the informal waste collectors into waste management systems, improve waste recycling rates, and tackle pressing health issues. 4 5 6 Linzner R, Salhofer S. Municipal solid waste recycling and the significance of informal sector in urban China. Waste Manag Res 2014; 32: 896–907. Ezeah C, Fazakerley JA, Roberts CL. Emerging trends in informal sector recycling in developing and transition countries. Waste Manag 2013; 33: 2509–19. Binion E, Gutberlet J. The effects of handling solid waste on the wellbeing of informal and organized recyclers: a review of the literature. Int J Occup Environ Health 2012; 18: 43–52. We declare no competing interests. The authors alone are responsible for the views expressed in this article and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated. This work was supported by SINOGRAIN and SIS Project (355002) projects. Copyright © Yang et al. Open Access article distributed under the terms of CC BY-NC-ND. *Hong Yang, Xianjin Huang, Julian R Thompson, Roger J Flower hongyanghy@gmail.com Norwegian Institute of Bioeconomy Research (NIBIO) and CEES, Department of Biosciences, University of Oslo, Blindern, Oslo, Norway (HY); School of Geographic & Oceanographic Science, Xianlin Campus, Nanjing University, Nanjing, China (XH); and UCL Department of Geography, University College London, London, UK (JRT, RJF) 1 2 3 China Government. 69 people found dead in Shenzhen landslide. 2016. http://www.gov.cn/ xinwen/2016-01/13/content_5032448.htm (accessed Jan 20, 2016). EM-DAT. The international disaster database. http://www.emdat.be/ (accessed Feb 10, 2016). Kennedy IT, Petley DN, Williams R, Murray V. A systematic review of the health impacts of mass Earth movements (landslides). PLoS Curr 2015; published online April 30. http://dx.doi. org/10.1371/currents.dis.1d49e84c8bbe678b 0e70cf7fc35d0b77. e452