Sources and properties of non-exhaust particulate matter from road traffic: a review.

Summary Electric vehicles (EVs) coupled with low-carbon electricity sources offer the potential for reducing greenhouse gas emissions and exposure to tailpipe emissions from personal transportation. In considering these benefits, it is important to address concerns of problemshifting. In addition, while many studies have focused on the use phase in comparing transportation options, vehicle production is also significant when comparing conventional and EVs. We develop and provide a transparent life cycle inventory of conventional and electric vehicles and apply our inventory to assess conventional and EVs over a range of impact categories. We find that EVs powered by the present European electricity mix offer a 10% to 24% decrease in global warming potential (GWP) relative to conventional diesel or gasoline vehicles assuming lifetimes of 150,000 km. However, EVs exhibit the potential for significant increases in human toxicity, freshwater eco-toxicity, freshwater eutrophication, and metal depletion impacts, largely emanating from the vehicle supply chain. Results are sensitive to assumptions regarding electricity source, use phase energy consumption, vehicle lifetime, and battery replacement schedules. Because production impacts are more significant for EVs than conventional vehicles, assuming a vehicle lifetime of 200,000 km exaggerates the GWP benefits of EVs to 27% to 29% relative to gasoline vehicles or 17% to 20% relative to diesel. An assumption of 100,000 km decreases the benefit of EVs to 9% to 14% with respect to gasoline vehicles and results in impacts indistinguishable from those of a diesel vehicle. Improving the environmental profile of EVs requires engagement around reducing vehicle production supply chain impacts and promoting clean electricity sources in decision making regarding electricity infrastructure.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1530-9290.2012.00532.x

Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles

https://research.birmingham.ac.uk/portal/files/11961623/Estimation_of_the_Contribution_of_Road_Traffic_Emissions_V3_PostPrint.pdf

Estimation of the contribution of road traffic emissions to particulate matter concentrations from field measurements: A review

EPA's Integrated Risk Information System (IRIS) is a human health assessment program that evaluates information on health effects that may result from exposure to environmental contaminants.

Integrated Risk Information System

Characterization of heavy metal particles embedded in tire dust.

Current particulate matter (PM) emission factor models estimate brake wear particulate matter emission rates using data derived from asbestos brakes. However, most brake pads are now produced from nonasbestos materials. Little work has been performed on emissions from brakes using these materials. Therefore, a brake wear study was performed using seven brake pad formulations that were in high volume use in 1998. Included were semi-metallic brakes, brakes using potassium titanate fibers, and brakes using aramid fibers. Brakes were tested on a brake dynamometer under four wear conditions. On average, 35% of the brake pad mass loss was emitted as airborne PM. The observed wear rates correspond to vehicle emission rates of 5.1−14.1 mg/mi. On average, 86 and 63% of the airborne PM was smaller than 10 μm in diameter (PM10) or 2.5 μm in diameter (PM2.5), respectively. The large number of particles observed in some wear tests was attributed to condensation, a process that is highly dependent on dilution condition...

Brake Wear Particulate Matter Emissions

Accumulation of α2u-globulin in the renal proximal tubules of male rats exposed to unleaded gasoline

Light microscopy was used to study the pathologic alterations in the rat lung after timed diesel exposures to 6000 micrograms m-3 of diesel particulates ranging from 6 h to 9 weeks. As a general reaction, an increase in alveolar macrophages containing diesel particles, an increase in type II pneumocytes, and an accumulation of inflammatory cells within the alveoli and septal walls was observed. Histochemical differentiation between type II cells and alveolar macrophages was clearly delineated by the use of the PAS (periodic acid Schiff) stain in which macrophages stained positive and type II cells negative for this reaction. After the 9-week exposure, the accumulation of macrophages and accompanying type II cell reaction resulted in the formation of alveolar complexes that seemed to be preferentially localized near the terminal bronchioles. The similarity of the lesion to that of 'macrophage alveolitis' produced in animals repeatedly exposed to coal dust is emphasized, although the ultimate clinical significance of the complex formation cannot be assessed within the time limits of the experimental observation.

Early pulmonary response of the rat lung to inhalation of high concentration of diesel particles

Hydrocarbon-induced hyaline droplet nephropathy in male rats during senescence

Unleaded gasoline induces nephropathy, characterized by rapid accumulation of hyaline (protein resorption) droplets in epithelial cells of the renal proximal convoluted tubules, only in male rats. The hepatic synthesis of the male rat-specific protein alpha 2u-globulin, a constituent of renal hyaline droplets, is unaltered by gasoline treatment (Olson et al., 1987). Renal alpha 2u-globulin content increased to 210% of control within 18 h of a single oral dose of gasoline (2.0 ml/kg); maximal levels (320% of control) were attained following gasoline administration for 3 d. Increases in renal alpha 2u-globulin caused by gasoline were accompanied by concurrent proliferation of hyaline droplets. However, within 3 d of terminating gasoline administration renal alpha 2u-globulin content decreased to the same level as that in unexposed rats, although renal hyaline droplet number returned to pretreatment levels somewhat more slowly. The conjoint effect of postexposure recovery and estradiol (an inhibitor of hepatic alpha 2u-globulin synthesis) administration was also determined in male rats. On postexposure d 3, 6, and 9, estradiol treatment (1 mg/kg, sc, 4 d, starting on d 9 of gasoline treatment) decreased renal alpha 2u-globulin content to 75%, 59%, and 48%, respectively, of that in rats allowed to recover from gasoline with no hormone treatment. Hepatic alpha 2u-globulin content in estradiol-treated rats was decreased by 74%, 97%, and 96% at the same intervals. Estradiol treatment during recovery from gasoline also appeared to increase the removal of accumulated hyaline droplets from the renal cortex. Thus, accumulation of alpha 2u-globulin-containing hyaline droplets after subacute exposure of male rats to gasoline is rapidly reversible, dependent on continuous exposure to gasoline and maintenance of the normal rate of hepatic alpha 2u-globulin synthesis. These results emphasize the dynamic state of renal cortical hyaline droplets and suggest strongly that gasoline hydrocarbons cause hyaline droplet accumulation by prolonging the half-time of degradation of alpha 2u-globulin.

Bhagwan D. Garg

Papers

Brake Wear Particulate Matter Emissions

Accumulation of α2u-globulin in the renal proximal tubules of male rats exposed to unleaded gasoline

Early pulmonary response of the rat lung to inhalation of high concentration of diesel particles

Hydrocarbon-induced hyaline droplet nephropathy in male rats during senescence

Rapid postexposure decay of alpha 2u-globulin and hyaline droplets in the kidneys of gasoline-treated male rats.