Microplastics are classified as any plastic particle less than 5 millimeters in diameter. They are ubiquitous throughout the environment and, subsequently, in the food and water we consume. The impacts of microplastics on organisms is an emerging research topic, however, most research suggests that the impacts of microplastic ingestion are likely negative. All forms of drinking water have been found to be contaminated with microplastics, including municipal, well, and bottled water. There are several different factors that could be contributing to variations in microplastic contamination across those drinking water sources, such as the bottling process for bottled water or the distance travel through plastic piping for municipal water. However, there have been no studies in this region evaluating microplastic contamination from several different municipal water sources. To address this question, we collected 5 replicate water samples from 15 different cities throughout coastal Mississippi. Each sample was collected in a 1L glass jar from the city hall in each respective city and immediately capped to prevent further contamination. The samples were then filtered through a 0.45um filter, stored in a closed petri dish, and then evaluated for microplastics under 40x magnification. Each microplastic was counted and categorized as either a fiber, film, fragment, or bead. Every sample taken had a significant level of microplastic contamination (>13 pieces per L) with fibers accounting for 94% of all microplastics. There was also a general trend where samples from cities in the western portion of coastal Mississippi had the most microplastics, followed by the eastern, and central portions. Future studies are needed, but research like this could help identify sources of microplastics and the water treatment practices that prevent them.

Aquatic Care Team (ACT): Empowering Students to Take Action The Navarre Beach Marine Science Station (NBMSS), a Santa Rosa County District School, is dedicated to educating students in the classroom, through research, and community outreach. The NBMSS has received a grant from NOAA to monitor the water quality of the Santa Rosa Sound. NBMSS sits along Santa Rosa Sound connected to the Pensacola Bay Watershed, a system impaired by pollutants and disturbance. Future water quality restorations will need baseline data to compare post-implementation monitoring to measure success, however, few data are available on water quality in the Navarre area. To fill this gap, Aquatic Care Team (ACT) students measure environmental variables of water quality to create a long-term dataset for this region in the Gulf Coast Ocean Observation Systems (GCOOS) database. ACT students who “learn, do, and teach” are more likely to retain and apply information than through learning alone; ACT provides the background knowledge to make informed decisions, suggest solutions, and communicate issues to local partner stakeholders and policy makers leading to watershed preservation in Santa Rosa County. ACT students participate in field data collections throughout the year at multiple sampling sites in the Santa Rosa Sound and conduct basic laboratory analyses at NBMSS. Collected water samples are sent to the University of West Florida (UWF) for advanced nutrient analysis. The project is funded by the NOAA Gulf of Mexico Bay Watershed Education and Training (Gulf B-WET) Program.

The primary objective of the study I will present on is to reconstruct multi-century streamflow records of the Mobile-Tensaw River Delta, utilizing standard dendrochronological techniques to better understand past and present trends in hydrologic and hydroclimatic extremes within the system. Tree-ring analyses of moisture sensitive trees provide a long-term assessment of streamflow variability and moisture, as well as valuable information about past hydroclimate. This research will improve the paleoclimate record for the Mobile-Tensaw River Delta and expand the broader understanding of the region’s hydrologic variability. The longest direct observations of streamflow and climate extend only back to the 1890s in the United States (U.S.), and often are significantly shorter. These records are insufficiently long to capture the frequency of severe droughts and floods or to observe long-term monotonic changes in climate, such as increased aridity, humidity, or changes in consumption. The comparatively short length of instrumental climate records limits the capacity to ascertain the relationships between streamflow and large-scale climatic signals. This limitation can be addressed through the creation of paleoreconstructions of streamflow and extreme hydroclimatic events (e.g., floods and drought). New tree-ring chronologies from the Mobile-Tensaw Delta watershed can supply the high-resolution records of climate variability needed to better understand the impacts of extreme events, multi-decadal trends in rainfall variability, and the influence of regional and large-scale forcing factors on hydroclimate variability (Therrell et al., 2017). In this lightning talk, I will share the latest findings of this project.

A common perception is that bottled water offers the cleanest option for potable water, leading many consumers to prefer bottled water over tap or well-water supplied directly to their residence. Within bottled waters, there is also a price gradient that carries a perception of a positive relationship between price and purity. However, microplastics are an emerging pollutant that often aren’t considered when choosing a potable water source. Throughout the pumping, bottling, transportation, storage, and opening processes, there are many potential avenues for microplastic contamination in bottled water. To evaluate microplastic concentrations in bottled water and across a price gradient, we purchased 10 – 1L bottles each of 10 separate brands of bottled water at a grocery store. The water within each bottle was vacuum filtered through a 0.45um filter, stored in a closed petri dish, and counted for microplastics. Microplastics were categorized as either fibers, fragments, microbeads, or films. A range of 2 to 307 pieces per liter, with an average of 29 pieces per liter. Fragments dominated all of the samples with about 85% of all plastics being fragments. Contrary to assumptions, results showed that both the most expensive brand of bottled water had the most microplastics (mean of 69 pieces per liter). The next highest concentration of microplastics was found in the least expensive brand of bottled water (49 pieces per liter). Overall, there were no trends between price and number of microplastics. Future studies on this topic exploring the influence of filtration, bottling, and transporting on microplastic concentrations in drinking water.