Scientists have found traces of several chemicals used to prevent aging and corrosion in automobile tires in leafy vegetables.
Through normal wear, tires release numerous small pieces of rubber, which remain in the atmosphere or are carried away by sewers and water courses. In the air, these particles can affect the cloud formation. In water, they leach compounds that have been shown to be toxic to wildlife.
New research adds to growing evidence that car tires are a considerable source of pollution. For the study, scientists tested leafy vegetables grown in Switzerland, Spain and Italy and sold in Swiss supermarkets. They also tested vegetables harvested directly from agricultural land in Israel.
Tire ingredients were found in 11 of 15 samples collected in Swiss supermarkets and in nine of 13 samples collected in Israeli fields. Among the chemicals discovered was 6PPD, an additive used to prevent cracking, which can turn into a compound that has proven deadly to coho salmon. O discoveries were published in Frontiers in Environmental Science.
Scientists say farmers may be introducing additives into tires, irrigating crops with treated wastewater or using sewage sludge as fertilizer. It is also likely that airborne particles are deposited on the ground. Tire chemicals are absorbed by crops and eventually consumed by people.
“Although concentrations and daily intake are fortunately relatively low, car tire additives are still found in foods,” said co-author Thilo Hofmann, researcher at the University of Vienna. “It’s not where they belong.”
