Your best bet for pine tar is a a good saddlers or equine centre - also known as stockholm tar. Be sure to get "pure" stockholm or pine tar though.
Pennyroyal oil is available from aromatherapy suppliers, but, please, go easy. It can be very dangerous - a report I read on it suggested that 3ml could kill a child if ingested. I think an ounce of neat essential oil sounds highly dubious to say the least. I suspect Nessmuk was referring to an infusion made of pennyroyal leaves in a carrier oil and not essential oil
Red
As little as 5ml of Eucalyptus oil will kill a child. I'd say the warning is treat
all "essential oil" with great care.
American pennyroyal , Hedeoma pulegioides L, also called fleabane or tickweed is different from English pennyroyal Mentha pulegium L
I have read reports, admittedly on the internet that oil up to 6% pure can be rubbed on the skin with no effects, and no uptake of the toxins. However, from the report said, I would not think that you would need to use anywhere near that amount.
six to ten drops of the oil in one fluid ounce of base oil, should be more than enough
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