A Study of the Levels of Some Toxic Substances present in Dry Holi Colours in Kolkata, India.

'Holi' is an Indian festival with a great cultural context, that is celebrated across the world at the onset of spring by applying dry powder of vibrant colours on friends and family. In ancient times holi colours were prepared from different spring flowers, but in modern times, these natural colours have been replaced by commercial industrial dyes prepared by chemical processes. Even products that claim to use organic colours, use synthetic pigments to enhance the brightness of hues. Such synthetic holi colours are sold as herbal colours, in an unregulated manner, in local markets, and no checks can be enforced on the product composition. Also, the quality and the amount of information about the ingredients of the particular packets are missing. These colours sold in the local market often contain hazardous chemicals such as endotoxins, and heavy metals, like lead, potentially causing moderate to severe health problem. Holi colour samples were randomly collected from different sites in Kolkata, India. Red, pink, violet, green and yellow coloured powders were obtained. The powders were prepared and analysed for lead content by Inductively Coupled Plasma-Mass Spectrometric method. Analysis of endotoxin content of different holi colours was also performed by Limulus Amebocyte Lysate test. The lead content was found to be almost 2 times higher in the holi colours, with yellow pigment having the highest concentration, than FDA Standard for maximum permissible limit in cosmetics, which was taken as a reference for safety limit of lead that is dermatologically applicable. The endotoxin levels are alarmingly high, with almost 35 times the FDA reference for dermatological safety limit. Special attention should be given to lead and endotoxin levels in holi colours as their consequences pose serious health threats. Therefore, quality control measures should be recommended for them, in par with products designed for long-term contact with the skin. © Association of Clinical Biochemists of India 2021.