Organic contaminants in the groundwaters of a lignite-bearing basin from northern Greece

The aim of this study is to identify potential toxic or environmentally relevant organic compounds in the aquifers of the Amynteo hydrogeological basin and to investigate a possible link of the identified organic contaminants with the Pliocene Amynteo lignites. For these purposes, 10 groundwater samples were collected from this area. A sequential liquid-liquid extraction procedure was applied and all extracts were analyzed by gas chromatography and gas chromatography-mass spectrometry (GC-MS) by means of a non-target screening approach. The results of the GC-MS analyses of the extracts are presented and discussed in this work. The identified organic compounds with a potential environmental relevance are: 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, triacetine, isopropyl palminate, isopropyl myristate, tributyl-, triethyl- and trioctylphosphates, N,N-dibutyl formamide, methyl dihydrojasmonate, nonylphenols and bumetrizole. However, all these organic micropollutants can derive either by anthropogenic emissions (plasticizers, industrial pollutants, pesticides, etc.) or by contaminations from the pump and the borehole structure itself. Noteworthy, coal-derived organic molecules (such as anthracene, fluorene, pyrene, phenanthrene, etc.) have not been detected. Hence, an influence of coal deposits to the groundwater quality is considered negligible.