The spring season, during which the weather changes, is believed to cause viral fever and cold. The playful throwing of natural coloured powders has a medicinal significance: the colours are traditionally made of Neem, Kumkum, Haldi, Bilva, and other medicinal herbs prescribed by Āyurvedic doctors.
A special drink called thandai is prepared (commonly made of almonds, pistachios, rose petals, etc.), sometimes containing bhang (Cannabis indica). For wet colours, traditional flowers of Palash are boiled and soaked in water over night to produced yellow coloured water, which also had medicinal properties. Unfortunately the commercial aspect of celebration has led to an increase in the use of synthetic colours which, in some cases, may be toxic.
This information on safe holi was recieved from Mr Shivshankar Dhondiyal Executive - Technical OG Corporation , Mumbai.