Search

Plastics have been incorporated into everyday life due to their versatility, yet when microplastic particles enter natural fluvial systems, they pollute the surrounding environment and pose potential human health risks. As state and federal agencies develop regulations for microplastics in natural systems, it is important to properly assess potential sources of pollution and the concentration of microplastic particles in freshwater environments; however, microplastic pollution in small streams can be complex to investigate because of their dynamic hydrography and lack of standardization in microplastic sample collection and quantification. In this study, a unique low-cost sampling station was designed to collect microplastics from surface water in a shallow urban freshwater stream. The goal is to understand the variation in microplastic concentrations across a watershed at baseflow. Surface water samples were collected and analyzed from five sites along Hunnicutt Creek, a suburban freshwater stream located in Clemson, SC. The sampling station was deployed in the upper water column long enough to allow 10 m3 of surface water through a sampling net. Seven sampling events occurred at five sampling sites across the Hunnicutt Creek watershed. Surface water samples indicate that the microplastic abundance increased from the top of the watershed (269 ± 30 particles/10 m3) to the bottom of the watershed (715 ± 93 particles/10 m3). Fibers were the dominant morphology identified in the system, which accounted for 99.7% of the microplastic particles sampled. There was a significant difference in the microplastic concentrations between sampling sites moving down the watershed (F = 53.27, df = 4, p < 0.001), with the highest concentrations at the bottom of the watershed (or at the confluence of the tributaries). This work contributes to the understanding of how microplastics move at low-flow/baseflow conditions in small freshwater streams, which are common throughout global communities. [ABSTRACT FROM AUTHOR]

The article discusses the global water crisis and the role of membrane technology, particularly reverse osmosis (RO), microfiltration (MF), and ultrafiltration (UF), in addressing water challenges by 2050. Membrane technology has evolved to provide safe, sustainable drinking water by treating unconventional water sources like seawater, brackish groundwater, and wastewater. The article highlights the advancements in RO membranes for desalination, the importance of MF and UF membranes for pathogen treatment, and the potential of other membrane technologies like electrodialysis (ED) and membrane distillation (MD) in water treatment by 2050. [Extracted from the article]

This document is a spotlight column from the journal Environmental Engineering Science, highlighting selected articles from the April through August 2024 issues. One article discusses the importance of accurately characterizing carpet dust microbial communities using DNA extraction and PCR amplification methods. The study found that established protocols could underestimate the quantity of microbes, particularly fungal species, and that sample size may impact results. Another article explores unintended consequences related to lead pipe corrosion control in a drinking water system. The addition of orthophosphate led to the formation of white precipitate that clogged plumbing fixtures, and the study identified the optimal phosphate dose for proper corrosion control. Lastly, a study examined the environmental impacts of academic conferences, with transportation being the largest contributor. The researchers suggested measures such as carpooling and minimizing food waste to reduce the carbon footprint of conferences. [Extracted from the article]

This document is a spotlight column from the journal Environmental Engineering Science, highlighting selected articles from the December 2023 to March 2024 issues. One article discusses a faculty mentoring program developed by the Association of Environmental Engineering and Science Professors (AEESP), which pairs junior faculty with mentors to support their professional development. The article emphasizes the importance of factors such as university type, personality, research area, parental and marital status, and race/ethnicity in the mentor-mentee pairing process. Another article explores the potential of vertical hydroponic systems using effluents from anaerobic membrane bioreactors to grow lettuce in urban areas with limited land access. The study demonstrates that proper lighting and knowledge of nutrient concentration are crucial for efficient lettuce growth. A third article investigates the role of membrane thickness and porosity in reverse osmosis (RO) and nanofiltration (NF) processes for desalination and wastewater treatment. The study finds that membrane porosity, determined by pore size and thickness, affects sodium chloride removal and ion flux. Lastly, a study evaluates sampling strategies for SARS-CoV-2 in wastewater treatment plants, highlighting the effectiveness of composite sampling for capturing overall community conditions and grab sampling for identifying specific outbreak locations. The information presented in these articles can be valuable for researchers and practitioners in the field of environmental engineering and science. [Extracted from the article]

Polyacrylonitrile membranes (PAN) have high stability against chemical agents, making them suitable for a wide range of applications as such Ultrafiltration processes. Ultrafiltration membranes composed of PAN/Superfine powder activated carbon (S-PAC) mixtures can be a good research route, aiming the development of a new separation processes for water treatment. The association of materials to form a single product can have technological and economic advantages in separation processes. In this study, S-PAC impregnated into PAN membranes were prepared, characterized and used, as a case study, to remove diclofenac (DCF) from water. The membranes (PAN/S-PAC) were synthesized with different concentrations of S-PAC (0.2, 0.6, 1.0, 3.0 and 5.0 wt%) by a phase inversion process. The results of the TEM characterizations of the S-PAC indicated the presence of micro and nanoparticles (∼10 nm) and tending to form micrometric clusters. The infrared spectra of the membranes were characteristic of PAN; however, vibrational bands attributed to the S-PAC spectrum were also observed, which indicated an interaction between the materials. The case study showed an increase in the water flux and in the DCF rejection efficiency, for composite membranes (PAN/S-PAC) with higher concentration of S-PAC. The results of static adsorption tests indicated that the mechanism of DCF rejection occurred predominantly by adsorption. There were indications that the PAN/S-PAC membranes formed a composite material and the PAN/S-PAC (3.0) presented the best study composition given the results. Although the research is in its initial phase, the results indicated that the composition can improve many water treatment systems. [ABSTRACT FROM AUTHOR]