The "shelf-life"can vary depending on the ingredients, but you can make the oil last longer by storing it in a cool, dry place away from any sources of heat or light. Most people use brown or dark blue bottles that are tightly capped.
The etiology for EC is unknown. However I commend you for your persistence and working to find the cure for you. Thank you for your comment and the information. Best...
It sounds like you have over-toned. Stop dying your hair and it should fade back to a brighter hue. You could also try washing your hair with a clarifying shampoo...
Cooking oil is not good for the skin and may cause a breakout. Coconut oil works well in this case because it easily moisturizes the face and has molecules small...
One alternative to spray preservative is to wash gently and pat dry with a soft cloth, then thinly coat them with petroleum jelly. This is not a truly "organic" method,...
Yes, you can store an excess of the paste in the refrigerator. Unless you freeze it, I would use the refrigerated left-over paste within three to four days.