Evaluation of Hydrogenated Resin Acids as Molecular Markers for Tire-wear Debris in Urban Environments

Abstract

To propose new molecular markers for tire-wear emissions, four dihydroresin acids, that is, 8-isopimaren-18-oic acid (I), 8-pimaren-18-oic acid (II), 13β(H)-abieten-18-oic acid (III), and 13α(H)-abiet-8-en-18-oic acid (IV), were identified and investigated for source specificities, distributions, and environmental stabilities. The absence of I-IV in natural sources and the linear correlations between dihydroresin acids with different skeletons in tires and in environmental samples demonstrated that I-IV are specific markers for synthetic rubbers. The ratio of III + IV to the sum of III + IV plus abietic acid showed the resin acids distribution between different environmental compartments receiving contributions from traffic and natural sources. The physicochemical properties and results of photolysis experiments suggested that I-IV can set lower limits for tire-wear contributions to environmental loads of particulate matter (PM) and polycyclic aromatic hydrocarbons with molecular weight ≥202. By comparing III + IV concentrations or (III+IV)/pyrene or (III+IV)/benzo[a]pyrene ratios in tires and those in environmental matrices, the contributions of tire-wear emissions to PM, pyrene, and benzo[a]pyrene were estimated to be 0.68 ± 0.54%, 6.9 ± 4.8%, and 0.37 ± 0.18% in roadside PM and 0.83 ± 0.21%, 0.88 ± 0.52%, and 0.08 ± 0.06% in rooftop PM.

Constrained source apportionment of coarse particulate matter and selected trace elements in three cities from the multi-ethnic study of atherosclerosis

“…This estimate is consistent with our model predictions in Table 2 with the exception of those from the unconstrained, individual-city models. The relatively low absolute contributions of tire wear to PM 10-2.5 (see Table A4) is also consistent with those reported elsewhere by Kumata et al (2011) using molecular markers.…”

Antimicrobial Potential of Natural and Semi-Synthetic ent-Kaurane and ent-Pimarane Diterpenes against Clinically Isolated Gram-Positive Multidrug-Resistant Bacteria

“…Semi-synthetic hydrogenated derivatives (8 and 25) had their structure confirmed by NMR data and also by comparison with previously reported data in the literature: Tincusi et al 34 for 8 and Kumata et al 35 for 25. Both structures are easily confirmed due to the small difference between them and their precursors.…”

Human health risk assessment of Tire and Road Wear Particles (TRWP) in air

“…Studies reporting on emission factors from tires in the absence of empirical measurements of TRWP were considered qualitatively; however, precedent was given to studies with measured data, in lieu of relying on modeled estimates of TRWP contribution. Several researchers have attempted to estimate the contribution of tires to particulate in the environment using a variety of proposed markers for tires, including metals (primarily zinc), tire chemicals, and rubber polymers (Cardina 1974;Pierson and Brachaczek 1974;Cadle and WIlliams 1979;Cadle and WIlliams 1978;Cadle and WIlliams 1980;Spies et al 1987;Kim et al 1990;Rogge et al 1993;Yamaguchi et al 1995;Kumata et al 1997;Rauterberg-Wulff 1998;Fauser 1999;Kumata et al 2002;Schauer et al 2002;Almeida-Silva et al 2011;Kumata et al 2011;Schmid 2000). In spite of these efforts, however, few authors report reliable estimates of TRWP in the air.…”