Contents lists available at ScienceDirect International Journal of Industrial Ergonomics journal homepage: www.elsevier.com/locate/ergon Trunk posture assessment during work tasks at a Canadian recycling center Benedicta O. Asante a,* , Brenna Bath b,c , Catherine Trask c a Community Health and Epidemiology College of Medicine, University of Saskatchewan, Canada b School of Physical Therapy, College of Medicine, University of Saskatchewan, Canada c Canadian Centre for Health and Safety in Agriculture, College of Medicine, University of Saskatchewan, Canada ARTICLE INFO Keywords: Recycling Musculoskeletal disorder Ergonomics Exposure assessment ABSTRACT Musculoskeletal disorders are common among waste workers but preventative effort is lagging behind. This exploratory study assessed trunk posture during waste sorting tasks via statistical and experimental means. Posture exposure exceeded levels previously shown and related to elevated risk of Low Back Disorders (LBD). Results show predisposition of waste workers to LBDs. 1. Introduction Population growth and economic development is leading to an in- creased generation of solid waste (Agbesola, 2013; Khalil and Milhem, 2004; Bolaane, 2006; Furedy, 1995), and this waste needs to be man- aged to prevent environmental hazards (Agbesola, 2013). The recycling sector is regarded as sustainable within the waste management hier- archy (Bolaane, 2006), and recovery of inorganic materials from solid waste has been identified as a key component in the management of waste (Agbesola, 2013). The term ‘recycling worker’ describes workers in a recycling sector who collect, sort, clean, and bag waste materials as a means of livelihood and contribute greatly to the recycling sector (Furedy, 1995). Recycling can be done formally or informally. Formal work has been described by Kay (2011) as an “explicit arrangement with set pay and/or benefits, a stable location, regular hours, and some type of payroll taxes and social security contribution. Informal work describes … work with little or no job security, does not have a con- tract, and might not have the same employer for more than a few weeks or months” (Kay, 2011). Although the management of waste is neces- sary, it is a job that Mehrdad et al. reported to be associated with a variety of “physical, biological, mechanical, chemical and psychosocial hazards” (Mehrdad et al., 2008). Globally, collection and sorting of waste is considered a high-risk occupation (Thirarattanasunthon et al., 2012). A number of studies have shown a high rate of LBD prevalence in the waste management industry. A study showed a reported 12-month prevalence of musculoskeletal disorders up to 60.8% (Abou-ElWafa et al., 2012), and a recent systematic review indicated a 12-month prevalence between 14% and 74% (Asante et al., 2018). Recycling workers have been found to have at least twice the risk of low back disorders as other workers in both Denmark (Poulsen et al., 1995) and Taiwan (Yang et al., 2001). The activities of recycling workers are considered to be physically demanding and seem likely to expose workers to risk factors typically associated with a high prevalence rate of musculoskeletal disorders (Poulsen et al., 1995; Yang et al., 2001). Although recycling workers are presumed to be exposed to ergonomic hazards, no known research has explicitly measured these occupational exposures in this occupational group. A recent systematic review conducted in 2016, identified several exposures, which authors suggest might be related to the development of LBD among waste workers (Asante et al., 2018). Awkward posture (Mehrdad et al., 2008; Poulsen et al., 1995; Betsinger et al., 2000; Gutberlet and Baeder, 2008; Ivens et al., 1998); repetitive motion (Mehrdad et al., 2008; Betsinger et al., 2000; Prasuna, 2013); lifting and manual handling (Yang et al., 2001; Betsinger et al., 2000; Da Silva et al., 2006; Ivens et al., 1998); high forces (Mehrdad et al., 2008; Abou-ElWafa et al., 2012); trunk twisting (Velasco Garrido et al., 2015); high physical work load (Gutberlet and Baeder, 2008; Ivens et al., 1998); were some of the suggested risk factors in the systematic review. However, these studies did not assess exposure to these risk factors nor make any statistical comparisons between risk factors and the devel- opment of low back disorders. Of all the potential workplace exposures recycling workers may encounter, static, repetitive, and prolonged awkward posture are of particular concern (Gutberlet and Baeder, 2008). Waste workers often squat, twist, and bend (Gutberlet and Baeder, 2008; Velasco Garrido et al., 2015) whilst sorting through waste for long hours. It has been hypothesized that cumulative awk- ward posture contributes to musculoskeletal symptoms and work https://doi.org/10.1016/j.ergon.2018.09.001 Received 25 January 2017; Received in revised form 28 August 2018; Accepted 5 September 2018 * Corresponding author. E-mail address: benedicta.asante@usask.ca (B.O. Asante). International Journal of Industrial Ergonomics 68 (2018) 297–303 0169-8141/ © 2018 Elsevier B.V. All rights reserved. T