The Interstate Technology and Regulatory Council (ITRC) will host a webinar on January 14th, 2025 which will summarize the ITRC Guidance Document on tire-derived chemicals 6PPD and 6PPD-quinone (6PPD-q). These chemicals, used as anti-degradants in tires, have been identified as contaminants of emerging concern due to their toxicity to aquatic species and potential human health impacts. The session will cover topics such as the background and use of 6PPD in tires, its transformation into 6PPD-q, the occurrence, fate, and transport of these chemicals in the environment, toxicity, and the current regulatory framework surrounding these contaminants. For those interested, registration to the webinar is open and can be accessed here.
A study published by Prada et al. quantified microplastics and PFAS in landfill leachate, wastewater treatment plant (WWTP) influent and effluent, and biosolids from four landfill-wastewater treatment systems in Illinois. A total of 27 grab samples were collected over the course of two years; samples were analyzed for 13 target PFAS and particle count and mass were quantified for microplastics. PFAS and microplastics were detected in all samples, with PFAS concentrations notably higher in landfill leachate compared to wastewater influent, while concentrations of microplastics were similar in magnitude. PFAS and microplastics concentrations were significantly lower in WWTP effluent compared to influent, with PFAS removal being more variable. This study gives insight into the fate of PFAS and microplastics with regards to wastewater treatment plants, and highlights areas for potential improvement within landfill-wastewater treatment systems to ensure these contaminants are not reintroduced into the environment.
Microplastics in the atmosphere may help form ice and clouds in a manner similar to dust particles. Researchers tested four common types of plastic—low-density polyethylene, polypropylene, PVC (polyvinyl chloride), and PET (polyethylene terephthalate) —to see if they could cause water or ice to form. They aged the microplastics using UV light, ozone, and chemicals to mimic real-world conditions. The study, published by the American Chemical Society, found that all the plastics could help ice form, but aging reduced this ability for most, —except for PVC. PVC's ice-forming ability actually increased, likely because aging smoothed out flaws in the material. While the study showed microplastics can influence cloud formation, the concentration needed to have a measurable effect is still unknown.
A recent study investigated how low-density polyethylene (LDPE) food packaging degrades under simulated conditions such as heating, freezing, ultraviolent (UV) light exposure, and microwave use. These treatments lead to significant generation of microplastics (10–5000 microns [μm]) and plastic-derived dissolved organic matter (DOM). Researchers observed rapid microplastic formation from all simulated conditions, with UV exposure causing the highest release. This study highlights the need for further evaluating plastic packaging during food preparation and storage as a source of human exposure to microplastics.
Battelle will be holding the 2025 Sediments conference January 27-30, 2025, in Tampa, FL. The four-day conference will kick off with half-day short courses and full day short courses on Monday. The program agenda includes five platforms dedicated to various sediment contaminant related topics, including microplastics. Tailored topics of interest include sampling methods/analysis, monitoring and risk characterization for management strategies, environmental assessment, remediation, and site management. Several staff from Gradient and Geosyntec will be presenting at the conference on various topics, including microplastics in sediment. Registration is still open for anyone interested in attending the conference.