I painted a mural with Bio Paint, a plant-based natural paint. it smelled like aromatherapy oils it was wonderful, felt like I could drink the stuff. It did not have a harsh feeling on the hands or smell.
However, Bio Paint have gone out of business now. There are two other natural paints. Volvox, a clay-based natural paint and Livos, another plant-based natural paint. I have used Volvox it is easy to paint with drys quickly and easy to wash off. Clay paint absorbs moisture balancing humidity and getting rid of odours. Livos is known to be good for oils, varnishes and finishes etc.
I would recommend using natural paint any day.