A recent study cautions that toxic chemicals from car tires could find their way into our food, as vegetables absorb pollutants. Austrian researchers discovered that particles breaking off from car tires contain hazardous substances that can be carried by wind and rain into sewage systems and rivers.
As sewage sludge and water are commonly employed as fertilizers in agriculture, tire particles can contaminate soil, pose risks to plant growth, and potentially make them unfit for consumption. The University of Vienna team estimates that, on average, an individual unknowingly deposits approximately one kilogram (2.2 pounds) of potentially harmful particles each year.
Researchers from the Centre for Microbiology and Environmental Systems Science have discovered that tire wear particles contain a range of organic chemicals, including highly toxic substances. These chemicals, if released in the root zone of edible plants and subsequently absorbed by the plants, can pose a health risk to consumers.
In the study, scientists introduced five chemicals to a lettuce plant, four of which are commonly used in tire production without any known harmful effects. However, the fifth chemical, called 6PPD-quinone, was found to be toxic. Although not directly involved in tire production, this chemical is produced as a byproduct when new tires are used. It has been associated with mass deaths of salmon in the United States.
The researchers’ measurements demonstrated that the lettuce plant absorbed all the compounds through its roots and transmitted them into the leaves. Interestingly the same occurred when the lettuce plants were exposed to chemicals indirectly instead of through tire residue. Over time the lettuce plants absorb the harmful chemicals from the tire abrasion particle. Tire substances interacted with lettuce plants, resulting in the formation of unidentified compounds.
Newly discovered compounds produced by plants during the processing of substances have raised concerns about their potential toxicity. Thorsten Hüffer, a senior scientist at CMESS, highlights the health risks these unknown metabolites pose. To further understand the impact, the research team aims to examine the potential transfer of tire-wear pollutants from roads to the food chain.