144 Microplastics in the Environment (Posters)

Microplastics are becoming increasingly ubiquitous on Earth. This session aims to address: sources and distribution of microplastics globally, characterization and quantification of microplastic hazards and impacts throughout the microplastic life cycle, and mitigation of microplastics-induced health effects

Monday, 20 October 2025
8:00 AM - 5:30 PM
HBGCC, Hall 1

When the Rubber Hits the Road: Estimating the Source of Tire Microplastic Pollution in Texas

Paper number: 144-9
Program: Technical Sessions
Time: 8:00 AM – 8:00 AM

Authors

Abstract

In 2010, global plastic production was approximately 313 million metric tons (Mt), with plastic waste estimates of 274 Mt. The fate of this plastic waste depends highly on the average income of the country and waste management policies. One facet of plastic pollution that developed countries face is the direct release of microplastics (particles 1µm to 5 mm) into the environment. Microplastics are a poorly understood set of emissions because of high mobility of the particles. Tires are a significant yet understudied source of microplastics, which through road abrasion emit individual particles typically ranging from 5 μm to 220 μm. The state of Texas contains approximately 26 million registered vehicles in 2024 which drive over about 680,000 miles of roads every year, according to Texas Depart of Transportation (TXDOT). One tire emissions per kilometer travelled have been estimated by measuring wight and tread loss on used tires. We estimate passenger vehicles (Light Duty) emit approximately 0.116 g/km of microrubber particles on average, with commercial vehicles (Heavy Duty) emitting 10x more (1.16 g/km) on average. Total tire microrubber emissions on Texas roads increased from about 12,000 tons in 1970 to over 100,000 tons in 2024. Using the TXDOT roadway inventory, which provides annualized traffic data (counts) and roadway segment lengths (Km), we calculated tire microrubber emissions values for every catalogued roadway in the state by cross. Unsurprisingly, large metropolitan areas such as Houston, Dallas-Fort Worth, San Antonio, and Austin are pollution hotspots due to large numbers of cars and dense road networks. This material is deposited by the roadsides, blown by wind, or transported by waterways. Texas river catchments are collecting the tire emissions with Trinity River (25% of the entire Texas), followed by the San Jacinto River (16%) that hosts the cities of Dallas and Houston, respectively, within their borders.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6

doi: 10.1130/abs/2025AM-413544

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