Release and quantification of organic and inorganic contaminants from geotextile materials in dynamic surface leaching test.

Geotextiles are frequently used in waterway construction, for instance as filtration or separation layers of river banks and canals. A variety of additives are added to improve their lifespan during application and avivage agents are applied to optimize the manufacturing process. Two nonwoven needle-punched geotextiles were leached with deionized water, groundwater and river water via the dynamic surface leaching test. Organic compounds released by the materials were identified via non-target screening using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS). A variety of the identified compounds belong to the groups of sulfates, (benzene)sulfonates, polyethylene glycols, phosphates, carboxylic acids (amides), plastic-oligomers, antioxidants and light stabilizers. The luminescence inhibition of Aliivibrio fischeri, observed in leachates of tested polyethylene terephthalate/polypropylene (PET/PP) geotextile, can mainly be attributed to the released anionic surfactant monododecyl phosphate, that was identified by a combination of biotests and chemical analysis. This surfactant is obviously used as an avivage agent during geomembrane production. Target analysis via inductively coupled plasma mass spectrometry (ICP-MS) and liquid chromatography mass spectrometry (LC-MS/MS) ultimately elucidated that elements such as antimony and zinc as well as a multitude of organic substances are mainly released at the beginning probably by wash-off effects, while their release after the third leaching step was negligible.