Ecotoxicological effects of Tire Road Wear Particles (TRWPs) collected from different asphalts
1
Department of Biosciences, University of Milan, Via Celoria 26, Milan, MI - 20133, Italy
2
Department of Chemistry, University of Milan, Via Golgi 19, Milan, MI - 20133, Italy
3
, Waste and Chemicals srl, Circonvallazione Gianicolense 216E, Rome, RM - 00152, Italy
4
COSR-Center for Omics Sciences, IRCCS Hospital San Raffaele, Via Olgettina 58, Milan, MI - 20132, Italy
5
, Environment and Climate Change Canada, 105 McGill, Montréal, Québec - H2Y2E7, Canada
6
Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno d’Alcontres 31, Messina, ME - 98166, Italy
Tire abrasion on the asphalt surface produces the so-called Tire Road Wear Particles (TRWPs), whose potential adverse effects on ecosystems are under consideration by the scientific community. Since the aquatic environment represents a reservoir of these contaminants, the aim of this project was to investigate the toxicity of TRWPs on Danio rerio (zebrafish) embryos. TRWPs were directly collected in the environment on different types of road surface, represented by rubberized (TRWP1), polymeric (TRWP2) and conventional (TRWP3) asphalts. Sampling was carried out using a vacuum system in different sections of the 73 Senese Aretina (SS73) State Road, which represents one of the few Italian routes with the contemporary typologies of the three abovementioned asphalts. The collected particles were sieved on a set of steel sieves (5, 4 and 1 mm) to remove the coarsest contaminants and characterized by Scanning Electron Microscopy (SEM) coupled with Energy Dispersive x-ray Spectroscopy (EDS). To confirm the presence of rubber particles in the samples, the hexamethoxymethylmelamine (HMMM), used in tire production as crosslinking agent, was quantified as TRWP marker. Subsequently, TRWP aqueous suspensions were prepared by 72 h stirring followed by 48 h settling. These suspensions were analyzed by Dynamic Light Scattering (DLS) to measure the eventual presence of particles in the aqueous medium. The organisms were exposed from 0 to 120 h post fertilization (hpf) to 10 and 100 µg/L of TRWP suspensions. To compare the effects between TRWP1 and TRWP3, based on the composition of the abrasive substrate, a wide battery of biomarkers of cellular stress, protein aggregation (amyloids), neuro-genotoxicity and alterations of heart rate and swimming behavior was applied. Moreover, the effect comparison between TRWP2 and TRWP3 were investigated through Omics techniques, such as gel free proteomics, metabolomics and transcriptomics (Next Generation Sequencing - NGS). The ecotoxicological analyses are ongoing.
L’ecotossicologia tra regolamentazione e nuove sfide per la sostenibilità ambientale