Most of the DIY OTC Japan Drier available now sport a 'Lead Free' lable.
Everyone likes lead free and many people are aware that the original drier used a lead metalic salt in it's make up.
So they feel comfortable not brushing on a layer of lead (in their mind) on their refinished coffee table project.

Synthetic Driers is another term often used in labeling them as w/a substitute for the lead.

But Japan Driers also used Cobalt and Manganese salts.
Some of the happy face Lead Free products label still contain Cobalt, especially. MSDS reveals a lot.
Not as bad for you I guess at this point. You don't self illumintate if using same.

The good old stuff with lead, cobalt and even both in the same bottle is still available. Usually from Artist Supply places on-line.
Artist oil brush painters still use it to make their work dry in a reasonable time.
Small bottles, that last forever proudly labeled containing the Lead and/or with Cobalt & Manganese.

The old 2gal tin(ned) can I have of J/Drier will last 'several lifetimes. Probably that quantity was from the oilbase house and barn painting days.
IIRC the recipe was one shot glass of J/Drier to a gal of paint
I hated painting a house...