Sapropel is natural remedy that has been applied externally via different topical applications or as a base for mud bath in skin care and health improvement procedures and can be classified as traditional remedy. Sapropel forms over long period of time in shallow waters by slowly decomposing organic sediment and has different compositions depending on the location of the lake, its surroundings, the water regime and the location of the sample in the sediment strata.
There is a revived interest in sapropel during the last decades and a steady growth in its use and popularity in medicine, rehabilitation and skincare. There are reports about the extraction of active ingredients from the sapropel for the use in cosmetic and pharmacological products. According to modern practice raw material control and quality assurance are essential and have to be developed for sapropel as raw material in medicine and pharmacology.
This work attempts to test and standardize freshwater sapropel from 5 different lakes in Latgale, eastern Latvia, for the use in medicine and pharmaceutical industry. Official geological survey of Latvia lakes from Latvian lake database (ezeri.lv), were used in the selection of lakes. The main selection criteria were sapropel deposits depth, hydrological regime, the history of agriculture next to lake and the potential exposure to industrial waste. 105 sapropel samples were obtained from 5 lakes during the winter time.
The following factors were identified for standardizing and describing sapropel: organoleptic testing (look, consistence and smell, coarse composition test), test for heavy metal residue, test for pesticide residue, bacteriological test) and pH.
Pb, Cd, Co, Ni, Cu were present in all samples none of the metals exceeded maximum acceptable level. Some samples showed the presence of DDT pesticide. Sapropel is still a living material with its specific biome and microbiological flora that is not yet identified in details. Coarse testing of the samples is ongoing; results will be available at the end of our study. pH level is between 7 – 8.
Humic, fulvic acid content - The concentration of humic and fulvic acids in samples are different in various mining sites, and sapropel strata levels.
Several storage temperatures ranging from room temperature to -20C were tested. 4C without exposure to light and oxygen were sufficient for preserving sapropel. In detail studies of the microbiological flora can give further insight in this issue.
Conclusion: Once the sapropel site has been tested by grid of samples from different positions in the lake and different depth and the site is certified, sapropel from the site can be used as a quality assured raw material for medicine and pharmacology. Each batch has to be tested organoleptically and by pH to ensure that sapropel corresponds to the certified site. Extended tests for the certification of the site should consist of organoleptic testing, heavy metal residue testing and pesticide testing and bacteriological testing for presence of harmful bacteria. Analytical testing for humic/fulvic content as well as other analytical can be included in the site characteristic.
The research was co-financed by project "Analysis of characteristics of medical sapropel and its usage for medical purposes and elaboration of industrial extraction methods", No.18.104.22.168/16/A/165
Audience take away:
• Learn about sapropel as a traditional remedy that can be standardized according to modern requirements in the health and pharmaceutical industries and will gain better understanding what sapropel is and how to characterize it.
• Will be able to apply the results and methods in the evaluation and use of sapropel as raw material in medicine and pharmacy and what potential usage in pharmacy and medicine it has as raw material.
• Our study gives guidelines how to characterize raw sapropel for medical and pharmaceutical purposes thus it can be used in teaching and courses on the use of natural and traditional remedies and give useful information for developing medical and pharmaceutical applications based on sapropel and its active ingredients.