Department of Environmental Science, University of Latvia, Raina Blvd. 19, Riga, LV-1586, Latvia.
Environ Geochem Health. 2018 Oct;40(5):1725-1738. doi: 10.1007/s10653-017-9912-y. Epub 2017 Jan 27.
Organic-rich freshwater sediments formed from the remains of water plants, plankton and benthic organisms, which are transformed by microorganisms, and mixed with mineral components supplied from the lake basin, are known as gyttja (sapropel or dy). Gyttja is a valuable natural resource that can be used in various fields such as agriculture, forestry, construction, chemical industry, balneology and the latter ones are especially interested in chemical composition and safety of natural materials. The aim of the study was to investigate micro- and macro-element content of gyttja derived from lakes of eastern Latvia (north-east of Europe). Depending on composition, sediment samples were identified as peaty, various algae, green algae, diatom, carbonate and organic-silicate types of gyttja. Dried samples were wet-digested by heating in HNO/HO solution until complete mineralization. Sample solutions were analysed by atomic absorption spectrometry (AAS) to detect concentration of Ca, Fe, K, Mg, Mn, Na and Zn, but inductively coupled plasma mass spectrometry (ICP-MS) was applied for As, Ba, Cd, Co, Cr, Cu, Li, Ni, Pb, Rb, Se, Sr and V concentration measurements. Total content of elements was variable; higher macroelement concentration was detected for gyttja of carbonate type, but higher microelement concentration-for organic-silicate gyttja. As concentration of several elements was much lower than permitted by the European Union legislation, gyttja is not only safe, but also highly valuable resource applicable in organic agriculture. There is a potential to use gyttja as a peloid in health care, but element bioavailability should be estimated likewise.
由水生植物、浮游生物和底栖生物的遗骸形成的富含有机物的淡水沉积物，经过微生物的转化，并与从湖盆供应的矿物质成分混合，被称为泥煤（腐泥或腐殖泥）。泥煤是一种有价值的自然资源，可用于农业、林业、建筑、化工、温泉疗养等各个领域，而后者特别关注天然材料的化学组成和安全性。本研究的目的是调查源自拉脱维亚东部湖泊（欧洲东北部）的泥煤的微量和常量元素含量。根据组成，沉积物样品被鉴定为泥煤、各种藻类、绿藻、硅藻、碳酸盐和有机硅酸盐型泥煤。干燥的样品通过在 HNO / HO 溶液中加热进行湿消解，直到完全矿化。使用原子吸收光谱法（AAS）分析样品溶液以检测 Ca、Fe、K、Mg、Mn、Na 和 Zn 的浓度，但应用电感耦合等离子体质谱法（ICP-MS）测量 As、Ba、Cd、Co、Cr、Cu、Li、Ni、Pb、Rb、Se、Sr 和 V 的浓度。元素的总含量是可变的；碳酸盐型泥煤的常量元素浓度较高，但有机硅酸盐泥煤的微量元素浓度较高。由于几种元素的浓度远低于欧盟法规允许的水平，因此泥煤不仅安全，而且是一种在有机农业中具有高应用价值的宝贵资源。泥煤有可能作为一种泥疗法物质用于保健，但同样需要估计元素的生物利用度。
