| Title | Environmental risk assessment of sodium laureth sulphate (SLES) contained in conditioning agents used in mechanized tunnelling |
| Abstract | Anionic surfactants (ANS) are a heterogeneous group of amphipathic compounds characterized by linear aliphatic chains (from C8 to C18) with a polar group (sulphate or sulfonate) neutralized with a counter ion. Given the variability of their molecular composition, ANS are considered mixtures. Among ANS, the sodium laureth sulphate (SLES) is the main component of commonly used foaming agents necessary to facilitate the excavation procedures in mechanized tunnelling. However, its use raises concern for the environment considering the presence of SLES residual concentration in soil debris. In addition, the absence of a soil threshold limit for SLES in the EU legislation does not facilitate the re-use of soil debris as by products (e.g. land covering). Consequently, a huge amount of such detritus can only be discharged as a waste with economic costs. In absence of a threshold limit, the environmental risk assessment (ERA) of foaming agents containing SLES can be a possible alternative to evaluate potential negative impact on ecosystems. However, the ERA can be limited by scarce knowledge data on the real ecological effects of SLES in foaming agent treated-soils and the site-specific characteristics (e.g. soil texture, microbial activity) which can lead to different levels of exposure. This study is part of a wider project aiming to develop a suitable methodology to identify environmental acceptable levels of SLES residues in soil debris produced during the tunnelling operations in Italy. Particularly, we report the results of ERA procedures performed using SLES residues from foaming agent-treated soils from tunnelling excavation sites. The risk has been characterized based on the exposure/toxicity ratios, where the exposure levels were predicted through predictive models or measured in micro/mesoscom studies. The ecotoxicity of SLES for terrestrial organisms (earthworms and plants) were experimentally determined in this study, whereas toxicity data for the aquatic organisms were gathered from literature. |
| Source | Conservazione, ripristino ed adattamento degli ecosistemi nell'Antropocene, Cagliari, 12-14/09/2018 |
| Keywords | TBM-EPBsoil debrisAnionic surfactantsfoaming agentsecological effects |
| Year | 2018 |
| Type | Abstract in atti di convegno |
| Authors | Finizio A., Grenni P., Patrolecco L., Galli E., Muzzini V.G., Fumagalli P., Rizzi C., Barra Caracciolo A. |
| Text | 399367 2018 TBM EPB soil debris Anionic surfactants foaming agents ecological effects Environmental risk assessment of sodium laureth sulphate SLES contained in conditioning agents used in mechanized tunnelling Finizio A., Grenni P., Patrolecco L., Galli E., Muzzini V.G., Fumagalli P., Rizzi C., Barra Caracciolo A. Finizio A, Fumagalli P, Rizzi C Department of Earth and Environmental Sciences, University of Milano Bicocca, Piazza della Scienza, 1 20126, Milano Grenni P., Patrolecco L., Barra Caracciolo A IRSA CNR Galli E, Muzzini VG IRET CNR XXVIII Congresso Societa Italiana di Ecologia SItE , Volume Atti Societa Italiana di Ecologia Published version https //www.ecologia.it/131 atti xxviii congresso site cagliari Conservazione, ripristino ed adattamento degli ecosistemi nell Antropocene Cagliari 12 14/09/2018 Internazionale Contributo Anionic surfactants ANS are a heterogeneous group of amphipathic compounds characterized by linear aliphatic chains from C8 to C18 with a polar group sulphate or sulfonate neutralized with a counter ion. Given the variability of their molecular composition, ANS are considered mixtures. Among ANS, the sodium laureth sulphate SLES is the main component of commonly used foaming agents necessary to facilitate the excavation procedures in mechanized tunnelling. However, its use raises concern for the environment considering the presence of SLES residual concentration in soil debris. In addition, the absence of a soil threshold limit for SLES in the EU legislation does not facilitate the re use of soil debris as by products e.g. land covering . Consequently, a huge amount of such detritus can only be discharged as a waste with economic costs. In absence of a threshold limit, the environmental risk assessment ERA of foaming agents containing SLES can be a possible alternative to evaluate potential negative impact on ecosystems. However, the ERA can be limited by scarce knowledge data on the real ecological effects of SLES in foaming agent treated soils and the site specific characteristics e.g. soil texture, microbial activity which can lead to different levels of exposure. This study is part of a wider project aiming to develop a suitable methodology to identify environmental acceptable levels of SLES residues in soil debris produced during the tunnelling operations in Italy. Particularly, we report the results of ERA procedures performed using SLES residues from foaming agent treated soils from tunnelling excavation sites. The risk has been characterized based on the exposure/toxicity ratios, where the exposure levels were predicted through predictive models or measured in micro/mesoscom studies. The ecotoxicity of SLES for terrestrial organisms earthworms and plants were experimentally determined in this study, whereas toxicity data for the aquatic organisms were gathered from literature. Abstract Abstract tratto dagli atti del convegno AttiXXVIII_Finizio.pdf Abstract in atti di convegno luisa.patrolecco PATROLECCO LUISA anna.barracaracciolo BARRA CARACCIOLO ANNA paola.grenni GRENNI PAOLA TA.P04.005.011 Vulnerabilita degli ecosistemi delle acque sotterranee e attenuazione naturale degli inquinanti nel suolo e nel sottosuolo |
