Determinants of single-use plastic bottled water consumption among university students: a cross-sectional study

Single-use plastic bottled water (SUPBW) is a major contributor to microplastic pollution. This study aimed to investigate factors influencing university students' consumption of SUPBW. This cross-sectional survey, conducted during the 2023-2024 academic year at the country's largest public university, used a self-administered online questionnaire and convenience sampling. The questionnaire was developed based on the Theory of Planned Behavior (TPB) and the Knowledge, Attitude, and Practices (KAP) frameworks. It included sections on general information, knowledge of environmental and health impacts, TPB constructs, and consumption behavior. Descriptive and regression analyses were conducted to identify factors associated with SUPBW (SUPBW) consumption. The study included 438 participants. Factors that were significantly associated with frequent SUPBW consumption included undergraduate enrolment (OR = 2.33, p-value = 0.02); higher household income (OR = 1.64, p-value = 0.02); lack of environmental literacy from courses (OR = 1.87, p-value < 0.01), initiatives (OR = 1.22, p-value = 0.021), and workshops (OR = 1.51, p-value < 0.01); peer pressure (OR = 3.86, p-value < 0.001); subjective norms from family and friends (OR = 1.91, p < 0.01); perceived behavioral control (OR = 2.68, p-value = 0.01); convenience (OR = 1.32, p-value = 0.015); and strong intentions to continue use (OR = 2.45, p-value < 0.001). In contrast, higher knowledge of environmental impacts and health impacts were associated with infrequent SUPBW consumption. In conclusion, to reduce SUPBW use, interventions should enhance environmental literacy, counter social pressures, and offer sustainable options.