At high temperatures such as 275F (135C), asphalt is a Newtonian
fluid. At
low temperature, asphalt is a non-Newtonian fluid.
View page
Not all non-Newtonian fluid is toxic. A good example of this
would be the synovial joints such as your knee making use of a
non-Newtonian fluid (synovial fluid)
There are a few that would be considered bad for your
health.