Mitigating microplastic exposure from water consumption in junior high students and teachers

Microplastics (MPs) are inorganic material that have been observed within items destined for human consumption, including water, and may pose a potential health hazard. Here we estimated the average amount of MPs junior high students and teachers consumed from different water sources and determined whether promoting awareness of microplastic (MP) exposure influenced choice of water source and potential MPs consumed. We hypothesized that MP exposure from water would be approximately 40 MPs/day. We conducted three surveys of 57 students and 26 teachers from a junior high school in Calgary, Alberta, Canada, asking participants to estimate how much tap and bottled water they consumed. Following the first survey, participants were given an educational presentation on MPs and their potential effects. At baseline, participants consumed 4-6 L/day of water, mainly tap (≥90%), which translated into MP consumption ranging from 23-83 MPs/day. Males consumed more MPs/day than females, and adults more than students. Male students drank the most bottled water and had the highest MPs/day. Following the educational presentation, <10% of participants changed the source of water consumed. Microplastic consumption remained highest among male students (115.89 MP/day) who drank the most bottled water. Our study's pre- and post-presentation MP consumption estimates for all groups except male students were lower than recent Canadian research that estimated humans' annual MP intake. Although an educational presentation did not influence the source of water intake or MP exposure, individuals' willingness to participate in these surveys and increase MP awareness suggests an interest in reducing plastic exposure.