Kohl (surma): retrospect and prospect.

Kohl, since antiquity has always been given a prime importance in ophthalmology for the protection and treatment of various eye ailments. However, for decades various conflicting reports in the literature have been published relating to Kohl application to eyes being responsible for causing higher blood lead concentration, which may cause lead poisoning. While at the same time, a number of research studies and reports have also been published negating any such links with increased blood lead level upon Kohl (surma) application. In view of the above mentioned facts, this review article is written with the objective to highlight various data from past and present research studies and reports about Kohl, so as to provide valuable information to both the users and the research workers about it's scientific background and effects when applied into eyes. A large number of items and topics (such as Kohl, surma, eye cosmetic, traditional eye preparations, environmental lead pollution, galena, lead sulphide etc.) have been taken into consideration while compiling this review article. In conclusion, the authors of this review article feel that the relation between Kohl and toxicity or increased blood lead concentration upon it's application to eyes as reported elsewhere is likely to be more of theoretical nature rather than a practical health hazard.