The TIP has a line that these particles tend to be of larger sizes and have a high density due to a 50-50 ratio of mineral and rubber.
It pains me to say this, but that view expressed throughout the tire industry is just wrong and highly misleading. A few particles can be characterised that way, but the vast majority (over 90%) do not have a 50-50 mix of mineral and rubber. The vast majority (over 90%) do not have a density of 1.8. The vast majority (over 90%) are far smaller than 100nm.
The tire industry claims to be science driven, but the science they are driven by appears to be geared to produce the results they want. They do not want to find evidence that shows the damage these particles are causing, so they design experiments that cannot show that damage.
Tire makers have the responsibility to minimise these emissions. These toxic emissions. These emissions that are killing salmon and getting into human bloodstreams and urine.
It is certainly true that more gentle driving will reduce emissions.
But it is also true that using an alternative to 6PPD is likely to reduce the deaths of millions of salmon.
Making tires with longer, heavier rubber molecules and stronger compounds and better dispersion of silica in the tread rubber will reduce the emissions and the load on our environment.
By framing the questions, tire makers have managed to persuade law-makers that the problem lies with cars and drivers, rather than themselves.
While the tire makers might be seeking to deny that a problem exists, we can take hope from the car emissions scandal, when there was an incident that showed the whole industry was complicit in producing fake data.
Eventually, something will emerge, that exposes the behaviour of tire makers.
We urge tire makers to take responsibility for their emissions and find good solutions, rather than hoping no-one ever finds out just how bad these emissions are.
Because – eventually – they will find out.