Promoting Sustainable Consumption: The Roles of Consumers’ Domain-Specific Environmental Knowledge and Personality Traits

Sustainable development, initially introduced in 1987 and exemplified by the United Nations’ 17 Sustainable Development Goals (SDGs) in 2015 [1], is becoming a societal megatrend. Environmental sustainability, as one of the crucial cores of sustainable development, is directly emphasized in SDG 6 (“Clean Water and Sanitation”), SDG 13 (“Climate Change”), SDG 14 (“Life below Water”), and SDG 15 (“Life on Land”) [1], and called for in SDG2 (“Zero Hunger“), SDG 7 (“Affordable and Clean Energy”), and SDG 12 (“Responsible Consumption and Production”) [1]. The environmental issues resulting from industrial development are increasingly drawing public attention to the environment and raising concerns about the future of industries [2].

The textile and apparel (T&A) industry holds a significant position in global manufacturing. Based on the 2022 report by the United Nations Alliance for Sustainable Fashion [3], the T&A industry was assessed as worth $2.4 trillion and supported a workforce of 300 million people. The T&A industry confronts a range of environmental challenges, including four main environmental issues: water scarcity, carbon footprint emission, waste management, and microplastic pollution [4]. The T&A industry is both the second-largest consumer of freshwater and the primary contributor to freshwater pollution [5]. On an annual basis, it accounts for approximately 4 percent of the world’s freshwater usage [5], is responsible for around 20 percent of global water pollution [6], generates an estimated 10 percent of global greenhouse gas (GHG) emissions [7], results in the loss of around 92 million tons of materials [8], and contributes to 9 percent of microplastic pollution in the world’s oceans [3]. These negative environmental outcomes drive the critical needs for the T&A industry to seek an environmentally sustainable development path.

Su et al. [9] suggested that the T&A industry is heavily consumer-driven. It is traditionally more likely to be dictated by consumers’ wants and needs. Other industries have also become more consumer-driven. However, this transformation inevitably leads to major changes in consumers’ lives, affecting their lifestyles and cultural practices [10]. For example, approximately 79 percent of consumers are altering their purchase preferences based on sustainability [10]. Consumer behaviors and actions within the pro-environmental context have become increasingly uncertain [11].

Although research on environmentally sustainable development within the T&A industry has increased markedly in recent years, the discussion on consumers has remained in its early stages [12]. Previous studies on consumer environmental behaviors in the T&A industry have focused primarily on psychological factors, such as attitudes, subjective norms, and beliefs [13]. However, the influence of environmental knowledge [14] and other psychological factors, including general environmental beliefs (GEBs) [15], a sense of personal environmental responsibility (PER) [16,17], and an environmental locus of control (ELOC) [18,19], on individual environmental behaviors has been increasingly substantiated in many industry sectors, particularly within the tourism and education domains [20]. The extent to which these findings are applicable and accurate within the context of the T&A industry remains uncertain. In addition, Granco et al. [21] reported that the effect (promotion or inhibition) of GEBs is influenced by their specific content (ecologism or anthropologism). Similarly, Yang and Weber [22] argued that the predictive power of ELOC also depends on specific contexts and behaviors. In past studies, the predictive power of environmental knowledge, especially domain-specific environmental knowledge, has often been underestimated or ignored in environmental behavior studies [14]. Substituting general environmental knowledge for specialized environmental knowledge to explain corresponding domain-specific performance is highly likely to lead to inaccuracies [14]. Additionally, Dunning and Helzer [23] proposed that subjective knowledge and objective knowledge may impact behavior in distinct ways because of differences in underlying psychological processes.

• to investigate the influence of subjective and objective environmental knowledge (SUEK and OBEK) of the T&A industry on SCI for T&A products;

• to examine the influence of personality traits, including PER, eco-centric and anthropocentric environmental beliefs (EEBs and AEBs), and internal and external ELOC (IN-ELOC and EX-ELOC), on SCI for T&A products.

Based on the ERB model theory of Hines et al. [20], this research explores the impact of consumers’ environmental knowledge in both forms within the T&A industry and three relevant personality traits, namely, PER, GEBs (EEBs and AEBs), and ELOC (IN-ELOC and EX-ELOC), on their SCI for T&A products. The information was processed using PLS-SEM. The research showed that individuals with a higher level of confidence in their knowledge of environmental aspects in the T&A industry are more inclined to engage in sustainable consumption within the T&A context. Additionally, those who hold a profound sense of personal responsibility toward environmental protection demonstrate a stronger intention to embrace the sustainable consumption of T&A products. Furthermore, consumers with eco-centric values or beliefs tend to exhibit a heightened inclination toward sustainable consumption of T&A products.

The findings of this research offer valuable implications for both academic researchers and stakeholders in the public sector. From an academic perspective, this study enhances the understanding of consumers’ SCI in the T&A industry and addresses identified research gaps. First, the research bridges sustainability and consumer behavior by applying the consumer behavior model (ERB model) to predict consumers’ SCI. This approach fosters interdisciplinary development in consumer behavior theories and explores sustainable practices in the T&A industry within the framework of sustainable development. The findings also underscore the importance of considering knowledge as a multidimensional construct [76], with SUEK and OBEK having distinct impacts on consumers’ SCI. These findings provide additional evidence that measuring consumer knowledge, particularly from an objective standpoint, remains challenging in the absence of accepted norms for environmental behaviors. Subjective environmental knowledge acts as a proxy in the context of T&A consumption until common acceptance of sustainability practices is established. Moreover, this research enhances the ERB model by extending it to the T&A industry context, introducing more specific knowledge elements (subjective and objective environmental knowledge of the T&A industry) and a new personality trait element (general environmental beliefs).

Like most of the empirical research, this study has several limitations. First, as some measurements used in this research lack robust literature-based validation and modification records, several items and one construct (AEBs) were removed to enhance model fit. This raises validity and reliability concerns regarding the measurement of these constructs. Future research should focus on developing and validating scales for measuring cognitive (SUEK and OBEK) and affective (PER, GEB, ELOC, and SCI) constructs in the T&A context. Second, the topic of environmental sustainability within the T&A industry context is dynamic, and this research has focused only on environmental issue knowledge, overlooking practical knowledge for addressing these issues. Considering topic trends, more representative measurement items should be included in future studies. Third, the scope of this study focused on the environmental dimension. According to the SDGs, T&A products are associated with two key sustainable practices: environmental sustainability and social sustainability [79]. Furthermore, due to limited time and resources, the data were restricted to college students from one large southeastern university, limiting the applicability of the findings to the broader population. In addition, future research may explore the possibility of conducting a multi-group analysis based on demographic variables for additional insights. Finally, the data collection questionnaire was defined based on the constructs for this study. Other variables should be considered in future studies according to the nature of the research and the literature review. Future research should investigate the intention–behavior gap, explore the link between SCI and actual behaviors, and consider situational factors as potential moderators to provide both practical and theoretical insights.