First, I have not read this article yet.
Standardizing artist paints came to the forefront in the art world around 1985. At that time most paints contained high levels of lead because this ingredient encouraged the paint to flow lightly enough to smooth out any brush strokes. Auto pinstriping paints were one of the most notorious for lead content.
The lead contents of the old paints can lead to blindness, deafness and mental retardation. They chip, peal and then are often eaten or consumed by small children, especially those in lower income housing. Lead can enter the blood stream through simple long term physical contact. Perhaps you do not care if someone elses child is terribly effected by lead or any other heavy metal posioning ... but I do.
Other heavy metal ingredients have since been added to the list of dangerous elements as all of the cadmium alloys/varities (?), magnesium, cobalt .....
I respect the referrence to "The Pearl Earring" but will add here that anyone truely interested do a little research into the number of artists during that time period and into the 20th century that suffered from mental illness and other diseases that resulted from their long term continuous use.
I also will refer to a more historically documented analogy ... during the 17 - 19 hundred men's hat makers used mercury as a binder in the felt band inside a man's hat. Those that worked in the hat factories suffered severly to the point that the trade earned the name "Mad Hatters".
Artists also have throughout history suffered as a result of those very ingredients that have now been eliminated because of standardization ... I guess to some that is amuzing.
In the US at that time the paint contents were standardized and many of the old ingredients ban because of the health hazards they can cause. During this same period the paint industries also began testing their colors of UV light stablity so that you as an artist can know which paints are most likely to fade quickly because of light deterioration. They also came to an agreed standard for color names and hues so that a tube of burnt umber from any company was a standardized match to a tube of burnt umber from another compnay.
As far as I know there are no laws or regulations that prevent an artist from mixing and creating their own paints for their own use. If you want to add ground lead to your paints you can, you simply can not sell that paint to any other person. If you wish to posion yourself I do not believe there is any law that prevents you from doing so.
And as for utility knives ...

... have you ever noticed that those that support the use of such knives over well tempered steel carving knives often are the same ones that scream "you must always wear a carving glove!" ... ironic isn't it.
So, in my opinion, it is not an issue or cause for a fight of any sort as not one is denying anyone else the right to mix their own paints ... the requirements only lie with those that create paints that are sold to the public.
Nor is whether you use a utility knife, carving glove, leather apron or tempered steel bench knife because it is only your body can be damaged ....
Susan
(OK ... I'm out of here to see why my Spell Checker program isn't working.)