History of Korean waste management policy. South Korea has achieved remarkable modernization and industrialization since the 1960 s, following the Korean War, through a series of five-year economic development plans (The Ministry of Environment, 1991). In 1960, the total population stood at 25 million. By 2012, it had more than doubled, reaching over 50 million.Footnote 1 As of 2018, the population density of Korea was ten times higher than the world average (UN Department of Economic and Social Affairs, 2019). However, in terms of waste generated per unit area, Korea ranks among the top four-member countries of the Organization for Economic Cooperation and Development (OECD) (Lee & Paik, 2011; Ministry of Environment, 2019). The growth of the human population and the increase in waste generated per unit area have combined with limited available landfills to make municipal waste an escalating issue in South Korea.

The Korean government’s waste management policies have undergone changes since the 1960 s (Yang et al., 2015), as outlined in Appendix B. In the 1990 s, the government recognized the need to reduce municipal waste and promote recycling, driven by the challenges of constructing waste disposal facilities (Lee & Paik, 2011). “Mandatory separate discharge” was introduced in 1991, and individuals faced administrative fines for failing to separate their household waste (The Ministry of Environment, 1991). Since 1995, a “volume-based waste fee system” (also known as a unit pricing system) has been in place, requiring households to purchase standard plastic waste bags for disposing of non-recyclable waste, with each local government having a different fee structure (The Ministry of Environment, 1991). Compared to 1994, just before the implementation of the volume-based waste fee system, the following year (1995) saw a significant shift. The total collection volume decreased by 8.4%, while the volume of household waste targeted for treatment (landfill or incineration) declined by 18.7%. Notably, there was a 31% increase in the collection of recyclables. This translates to an 8.8% point jump in recycling throughput compared to total household waste generation, rising from 20.5% in 1994 to 29.3% in 1995.Footnote 2 In the 2010 s, the government introduced a policy to “limit the use of disposable products.” As a result, large retail stores are prohibited from providing disposable plastic bags, and customers are required to purchase shopping baskets or use standard waste bags. The cost of a 20 L standard plastic waste bag ranges from approximately 300 to 800 KRW (approximately 0.2 to 0.6 US$), as described in Appendix C (The Ministry of Environment, & Korea Environment Corporation, 2018).

In addition to these environmental challenges, demographic changes are also underway. South Korea has gone through the fastest population aging. As of 2024, one in five citizens was 65 or older (Jung, 2024). By 2030, older adults are projected to comprise approximately one-quarter of the population. Considering the growing share of older adults in society, their participation in waste reduction and recycling becomes increasingly crucial for sustainability. This demographic context underscores the importance of examining how different age cohorts engage in waste management behaviors.

Cohorts in South Korea. Korean society and economy have undergone significant changes since the Korean War. Many studies have demonstrated that different generations exhibit distinct characteristics that differ from those of other generations, including values, lifestyles, attitudes towards citizenship, and consumer behaviors (Choi et al., 2015; Kim & Huh, 2007; Kwon, 2016; Suh & Suh, 2016). The baby boomer generation, born after the Korean War, experienced challenging economic times and played a significant role in driving rapid economic growth through national policies, such as five-year economic development plans implemented since 1962 (Suh & Suh, 2016). They tend to be family-centered and have a culture of saving and frugality. Generation X, who experienced democratization in their adolescence and benefited from economic affluence and industrialization, tends to be consumption-oriented and individualistic (Park, 2009). Generation Y, also known as echo boomers, refers to the children of baby boomers. They experienced the financial crisis known as the IMF (International Monetary Fund) Crisis in their adolescence and still suffer from income polarization, often exhibiting both pragmatic and hedonistic tendencies (Kim & Huh, 2007). Studies by Kim and Huh (2007) and Kwon (2016) suggest that there are generational differences in consumption behavior. Kim and Huh (2007) found that Generation Y enjoys the shopping experience itself, exhibiting more sensory-driven and pleasurable consumption patterns compared to Baby Boomers and Generation X. Kwon’s research (2016) aligns with this, indicating that eco-generations prioritize hedonistic values during consumption, while Baby Boomers value aesthetics and self-expression more (Kwon, 2016).

Waste management behaviors include both waste reduction and recycling. Waste reduction refers to efforts to reduce waste generation at the source, also known as waste minimization or prevention (Barr, 2002), such as avoiding the use of disposable products. Recycling behavior involves the primary separation of waste at home, including distinguishing recyclables from other waste, preparing items for collection, and placing them in the correct bin (Varotto & Spagnolli, 2017). While waste reduction is generally a voluntary pro-environmental behavior, recycling is compulsory in South Korea under law.

Waste management behaviors can be broadly attributed to three groups of factors: socioeconomic, infrastructural, and psychological factors (Corrado et al., 2022). Socioeconomic factors, including age, gender, level of education, income, and housing type, have been linked to waste management behaviors. Barr (2002) stated that “as a very crude stereotype, it has been found that young, female, single-family dwelling, high-income earning, well-educated, and politically liberal individuals tend to play an active part in waste management activities” (p.439). Barr (2002) found that gender has a moderately strong effect on waste reduction behavior, and Lee and Paik (2011) and D’Amato et al. (2016) found that women were more likely to recycle than men. Several studies have examined the impact of an individual’s education on waste management behaviors, suggesting a positive correlation between recycling and educational level (Berger, 1997). Income has been widely found to be positively associated with waste management behaviors (Lee & Paik, 2011; Watts et al., 1999).

The influence of age on waste management behaviors remains inconclusive. Some scholars suggest that aging processes can have both positive and negative effects (Shaw, 2017). For instance, as individuals reach middle adulthood, they may become more inclined to recycle in order to leave an environmental legacy for their children, while in later years, physical or time constraints may hinder their active engagement in waste practices (Shaw, 2017). Younger cohorts may also benefit from greater exposure to educational materials on environmental behaviors, as highlighted in a meta-analysis by Hines et al. (1987). However, a substantial body of research points to a positive association between age and pro-environmental waste behaviors, with older individuals often recycling more and generating less waste (Barr, 2007; Derksen & Gartrell, 1993; Lee & Paik, 2011; Oskamp et al., 1991; Vining & Ebreo, 1990). Perry and Williams (2007), for example, found that first-generation older immigrants in the United States reported higher rates of waste reuse and minimization than younger generations, attributing this to formative experiences of extreme poverty and the inability to afford disposal services. Barr (2007) observed that Britons who lived through WWII-era rationing tended to waste less, suggesting that historical experiences can instill durable pro-environmental habits. Lee and Paik (2011) likewise noted that older adults in South Korea were more likely to recycle, potentially due to greater exposure to waste problems and heightened sensitivity to social concerns.

Recycling behavior is influenced by access to recycling facilities, which are often closely linked to housing types. Individuals in apartments tend to recycle less than those in single-detached houses in Canada due to the lack of access to curbside recycling bins (Berger, 1997). In contrast, studies in South Korea have shown that apartment residents recycle more, as apartments tend to have more convenient recycling systems than single-detached houses (Yi et al., 2001; Yi, 2000). In Korea, the convenience for waste separation varies depending on housing type. Single-detached houses offer the least convenience, as they have limited days for waste disposal due to local government regulations, such as one specific day per week. Multi-household dwellings allow for anytime discharge, but the size and classification system for separate bins may be limited. Apartments tend to offer the most convenient infrastructure for waste management. Residents can dispose of waste at any time, and the apartments often have dedicated waste management offices that handle separation with a broader range of categories and larger bin sizes, promoting responsible waste disposal and better hygiene.

Psychological factors include environmental attitude, response efficacy, and perceived convenience level. Environmental attitude has been linked to waste management behaviors. Environmental attitude refers to human subjectivity towards the environment and society in which we live, and the term has been used interchangeably with other concepts such as environmental concern and environmental value (Barr, 2002, 2007). In general, environmental attitude is expected to increase pro-environmental behavior; however, the relationship between environmental concern and pro-environmental behavior was not found to be statistically significant in some studies, and the explanatory power was usually low to moderate (Bamberg, 2003; Eom et al., 2016; Kollmuss & Agyeman, 2002). Response efficacy refers to the perception of how well a given behavior will reduce a given problem (Barr, 2002) and has also been linked to waste management behaviors (Arbuthnot, 1977; Hopper & Nielsen, 1991). Perceived convenience level, the perceived simplicity of undertaking a given behavior, has also been a significant psychological factor of waste management behaviors (Barr, 2007; Gamba & Oskamp, 1994; Vining & Ebreo, 1990). Additionally, research suggests a connection between waste management behaviors and an individual’s personality and values. For example, Swami et al. (2011) found that lower Machiavellianism, lower political cynicism, and higher conscientiousness were associated with better waste management.

Waste reduction and recycling behaviors are likely to be driven by different factors because, based on different waste management policies, avoiding the use of disposables is a voluntary pro-environmental behavior, while separating household waste is a mandatory behavior, compelled by law. Different age cohorts are likely to adopt different waste management behaviors due to the fact that the socioeconomic environment and waste management policies in South Korea have undergone radical changes. Many factors can drive waste behaviors, and these factors themselves might not affect all groups equally. However, to date, little research has examined how different age cohorts may vary in both their waste behaviors and the drivers of those behaviors, especially in a society like South Korea that has undergone rapid change. The present study aims to answer two questions. First, what are the cohort differences in waste management behaviors? Second, how are factors associated with waste management behaviors different across cohorts?