https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3087745/Castor bean contains ricin a very potent toxin, the oil is also not recommended by doctors due to overdose risk.
Palm oil isn't toxic but it's problematic as palm oil farming leads to much of our deforestation. I avoid it in life in general.
I do a great deal of research when it comes to plant extracts of various types, using books & publications which go back hundreds of years, as well as more modern books, and have been formulating plant-based products for decades. I grew up learning from my grandmothers, aunties etc. I'm traditionally & independently educated in this 'field'. All of the colorants, oils, butters etc I use in my products, soap & skin care, are all derived from plants. I make my own medicine, which my family members also use. We've been doing this for hundreds of years without even ONE death or incident of poisoning due to the utilization of plants as our main 'treatment' method when it comes to any illness or injury. Pharmaceutical companies WISH they had this type of safety record.
There have never been any reliable reports in relation to castor oil causing poisoning of anybody in all of its long history of use.
Castor oil is NOT toxic. It has been used internally & externally for a very long time. It is also specifically used for healing by utilizing castor oil in what are known as castor oil packs, which are highly effective.
The only risk of any toxicity in castor oil is from the hexane used to press it, if any hexane remains behind in the oil. Hexane is some nasty stuff. The solution to avoiding hexane is buying the 'hexane free' type of castor oil.
Doctors often don't know much of anything, especially when it comes to skin, or any type of natural substance. They have zero education in natural substances, especially those coming from plants.
Any doctor speaking of potential 'overdose' of castor oil is an idiot
A person would either
their pants or
their cookies long before they could possibly reach any type of toxic level of ingesting castor oil, and even then, they'd simply have a smelly mess in their pants or on their carpets. Horrible to clean up, yes, but 'dangerous'?