If you have stayed in London for any amount of time or lived there, you may have experienced what Londoners call “London throat”, which includes mucus in the nose and illness. It turns out that vanadium, found in brake dust and in diesel exhaust contributes to “London throat” and also has an adverse impact on immunity.
The metal particles in the dust from worn-out brake pads on vehicles can be just as harmful as diesel emissions. Called BAD for Brake Dust Abrasion, studies done by King’s College London found that the metallic dust from brake pads cause lung inflammation and “reduce immunity, increasing the risk of respiratory infections.”
As reported in the BBC the head researcher Dr. Liza Selley stated “Worryingly, this means that brake dust could be contributing to what I call ‘London throat’ – the constant froggy feeling and string of coughs and colds that city dwellers endure.”
In her research Dr. Selley found that 55% of traffic pollution is from non-exhaust particles, and 20% of that is brake dust. The dust is caused by the friction of the brake rotor grinding on the brake pads when a vehicle is braked, and the dust becomes airborne. Her research shows that the impact of this dust is just as severe as that of diesel particles. You can read Dr. Selley’s complete study here.
What this also means is that zero emission vehicles which have been vaunted as the environmental salvo to the internal combustion engines of 20th century vehicles are still going to contribute to brake dust. This speaks to doing more with less, by using public transit in cities as opposed to individual vehicles in high density areas that are subject to vehicular pollution.
It’s no surprise that the pro-automobile lobby has come out saying that all speed bumps should be removed from city streets to minimize brake dust, as reported in the Daily Telegraph.
While that may solve one issue it does contribute to another, that of speeding vehicular traffic’s impacts on livability as well as the increase of serious injury and fatalities.
The study also shows that as zero emissions vehicles reduce auto exhaust, the impact of brake dust will be even more significant. Further studies will examine the long term impacts of brake dust on city dwellers’ health.
Images: EBCbrakes.com & Imperial.UK.com
The conclusion is that materials in brake pads and discs need to change, after all even mass transit has brakes, no?
“The study also shows that as zero emissions vehicles reduce auto exhaust, the impact of brake dust will be even more significant”
not sure the study reads that.
In fact electric vehicles also reduce impact of brake dust, since they also – and mainly – break via electrical regeneration (due to this you use much less the break pad on an electric vehicle than on a combustion one).
Skytrain and trolley also use regenerative breaking. and at the end brake dust is probably a more severe issue in confined system (like subway tunnel) .
Indeed regen (electrical regeneration when braking) is one of the top attributes of EVs and one key attribute to car longevity and reduced op costs.
Where’s the regulation to reduce diesel exhaust from trucks and buses? Where’s the demand to have at least hybrid trucks and buses for the constant stop and go in cities ? Pure EVs or e-trucks or e-buses not yet viable for long distance for surely hybrid is viable TODAY. It’s been around for cars for 20 years. Why not for heavy trucks or buses which generate much of the urban air pollution (incl braking) ?
Typical ICE cars go 25k to 65k miles before brake pads wear out. Teslas with regenerative braking can go 200k – 800k miles before changing brake pads because instead of using break pads to do most of the braking, they use the motor in reverse to slow the car down and regenerate electricity to the battery (called regenerative braking). So, no, zero emission vehicles do not contribute anywhere near the same amount of brake dust as conventional cars, as long as they use regenerative braking.
My friend was demonstrating his regenerative braking with his Tesla. Pretty much all normal traffic braking scenarios can be done with regenerative braking (such as pulling up to a stop sign or traffic light).
Indeed. So why not require it for trucks and buses in cities? With ever more e-commerce due to online shopping we need to take a serious look at truck traffic in cities incl heavy and light trucks. Retailers are dying but we allow diesel spewing truck growth unabated and untaxed? Not even a road toll, per km?
Hybrid technology is not new. Every truck and bus ought to have it by now, by law. It would reduce CO2 emissions but far more importantly reduce city air pollution incl brake dust.