Project period: 1 January 2017 - 31 January 2020

Clean drinking water is crucial to human health and wellbeing. The ambition of the NaToxAq ETN network is to expand the research basis for EU’s leading role in securing high quality drinking waters for its citizens. Focus is on natural toxins – a large group of emerging contaminants with unknown impact on drinking water resources. Both known toxins, like cyanotoxins, cyanogenic glucosides and terpenes and not yet explored toxins will be investigated. Twenty leading universities, research institutions, and water enterprises will pioneer the field through joint training of 15 ESRs investigating natural toxin emission via water reservoirs to water works and consumers.



The natural toxin challenge is addressed by the concerted work of the ESRs within 4 scientific work packages comprising origin, distribution, fate and remediation. Priority toxins are selected using in silico approaches accompanied by novel non-targeted and targeted analyses to map natural toxins along vegetation and climatic gradients in Europe. Invasion of alien species, toxin emission, leaching and dissipation will be under strong influence of climate change.

Data collected for toxin emission, properties and fate will be used to model effects of climate, land use, and design of remediation actions. Special attention will be paid to toxin removal at water works including development of new technologies tailored to remove natural toxins. The results will contribute to strengthening of European policies and regulation of drinking water, while new business opportunities within the fields of water supply and treatment, chemical monitoring and sensing, and the consulting sector will arise from academia-indstry collaborations.

The urgency of the challenge, its eminent knowledge gaps, its multifaceted and multidisciplinary nature, and the need for scientific and public awareness to be communicated by ESRs in a balanced way makes the topic ideal for a European mobility and training network.










Great and highly interesting papers are being published and we can start to integrate the results and see patterns, and a first step was taken at the NaToxAq Conference. We have got to know many more and new natural toxins in natural waters thanks to intensive work with natural toxin prioritization, sample preparation and analytical work, and different monitoring strategies. We know more about toxin production, release, fate processes and transport, and first attempts to model natural toxin exposure are taken. We are getting insights into new ways of cyanotoxin exposure and on how we can remove natural toxins at water works, and the basis for risk assessment work is strongly improved.




[50] Hama, J.; Jørgensen, D.B.G.; Diamantopoulos, E.;  Bucheli, T.D.; Hansen, H.C.B.; Strobel, B.W. (2022) Indole and quinolizidine alkaloids from blue lupin leach to agricultural drainage water. Sci. Tot. Environ. 834: 155283

[49] Kisielius, V.; Drejer, M.; Dornhoff, J.K.; Skrbic, N.; Lindqvist, D.N.; Hansen, H.C.B.; Rasmussen, L.H. (2022) Occurence and stability of carcinogenic illudane glucosides from Bracken in surface waters. Environmental Science: Processes and Impacts. 24: 277.

[48] Jones, M.R.; Pinto, E.; Torres, M.A.; Dorr, F.; Mazur-Marzec, H.; Szubert, K.; Tartaglione, L.; Dell’Aversano, C.; Miles, C.O; Beach, D.G.; McCarron, P.; Sivonen, K.; Fewer, D.P.; Jokela, J.; Janssen, E.M.-L. (2021) CyanoMetCB, a comprehensive public database of secondary metabolites from cyanobacteria. Water Res. 196: 117017.

[47] Schneider, M., Grossi, M. F., Gadara, D., Spáčil, Z., Babica, P. & Bláha, L. (2021). Treatment of cylindrospermopsin by hydroxyl and sulfate radicals: Does degradation equal detoxification? Journal of Hazardous Materials. (in press)

[46] Gunthardt, B. F., Wettstein, F. E., Hollender, J., Singer, H., Harri, J., Scheringer, M., Hungerbuhler, K. & Bucheli, T. D. (2021). Retrospective HRMS Screening and Dedicated Target Analysis Reveal a Wide Exposure to Pyrrolizidine Alkaloids in Small Streams. Environmental Science & Technology, 55, 1036−1044

[45] Mrkajic, N. S., Hama, J. R., Strobel, B. W., Hansen, H. C. B., Rasmussen, L. H., Pedersen, A-K., Christensen, S. C.B. & Hedegaard, M. J. (2021). Removal of phytotoxins in filter sand used for drinking water treatment. Water Research, 205, 117610

[44] Hansen, H. C. B., Hilscherova, K.& Bucheli, T. D. (2021) Natural toxins: environmental contaminants calling for attention. Environmental Science Europe, 33(112)

[43] Hama, J. R., Kolpin, D. W., LeFevre, G. H., Hubbard, L. E., Powers, M. M. & Strobel, B. W. (2021). Exposure and Transport of Alkaloids and Phytoestrogens from Soybeans to Agricultural Soils and Streams in the Midwestern United States. Environmental Science & Technology. 55, 11029−11039

[42] Günthardt, B. F., Hollender, J., Scheringer, M., Hungerbühler, K., Nanusha, M. Y., Brack W. & Bucheli, T. D.(2021). Aquatic occurrence of phytotoxins in small streams triggered by biogeography, vegetation growth stage, and precipitation. Science of the Total Environment, 798

[41] Filatova, D., Jones, M.R., Haley, J.A.,  Núñez, O., Farré, M, Janssen, E.ML. (2021). Cyanobacteria and their secondary metabolites in three freshwater reservoirs in the United Kingdom. Environmental Science Europe, 33(29)

[40] Picardo, M., Núñez, O. & Farré, M. (2021). A data independent acquisition all ion fragmentation mode tool for the suspect screening of natural toxins in surface water. MethodsX, 8,101286

[39] Wu, J.S., Clauson-Kaas, F., Lindqvist, D. N., Rasmussen, L. H., Strobel, B. W. & Hansen, H. C. B. (2021). Does the natural carcinogen ptaquiloside
degrade readily in groundwater? Environmental Sciences Europe, 33(24)

[38] García-Jorgensen, D. B., Diamantopoulos, E., Kisielius V., Rosenfjeld, M., Rasmussen, L.H., Strobel B.W. & Hansen, H. C. B. (2021). Bracken growth, toxin production and transfer from plant to soil: a 2‑year monitoring study. Environmental Sciences Europe, 33(45)

[37] Skrbic, N., Kisielius V., Pedersen, A., Christensen, S. C. B., Hansen, H.C.B. & Rasmussen, L.H. (2021). Occurrence of carcinogenic illudane glycosides in drinking water wells. Environmental Sciences Europe, 33(44)

[36] Schönsee, C. D., Wettstein, F. E. & Bucheli, T.D. (2021). Disentangling Mechanisms in Natural Toxin Sorption to Soil Organic Carbon. Environmental Science and Technology, 55, 8, 4762–4771

[35] Schönsee, C. D., Wettstein, F. E. & Bucheli, T.D. (2021). Phytotoxin sorption to clay minerals. Environmental Sciences Europe, 33(36)

[34] Liang, X., Christensen, J. H. & Nielsen, N.P. (2021). Enhancing the power of liquid chromatography–Mass spectrometry for chemical fingerprinting of phytotoxins in the environment.  Journal of Chromatography A, 1642

[33] Nanusha, M. Y., Krauss, M., Strobel B.W., Sørensen, B.G., Schulze, T.,  & Brack, W. (2021) Occurrence of plant secondary metabolite fingerprints in river waters from Eastern Jutland, Denmark. Environmental Sciences Europe 33(25)

[32] Natumi, R., Marcotullio, S. & Janssen, E.ML. (2021). Phototransformation kinetics of cyanobacterial toxins and secondary metabolites in surface waters. Environmental Sciences Europe 33(26)

[31] Kubíčková, B., Ramwell, C., Hilscherová, K. & Jacobs M.N. (2021). Highlighting the gaps in hazard and risk assessment of unregulated Endocrine Active Substances in surface waters: retinoids as a European case study. Environmental Sciences Europe 33(20)

[30] Griffiths, M.R., Strobel, B.W., Hama, J.R. & Cedergreen, N. (2021). Toxicity and risk of plant-produced alkaloids to Daphnia magna. Environmental Sciences Europe33(1), pp.1-12.

[29] Picardo, M., Sanchís, J., Núñez, O. & Farré, M. (2020). Suspect screening of natural toxins in surface and drinking water by high-performance liquid chromatography / high-resolution mass spectrometry. Chemosphere, 261, 127888

[28]  Hama, J. R. & Strobel, B.W. (2021). Occurrence of pyrrolizidine alkaloids in ragwort plants, soils and surface waters at the field scale in grassland. Science of The Total Environment, 755(1), 142822; DOI

[27] Filatova, D., Picardo, M., Núñez, O. & Farré, M. (2020). Analysis, levels and seasonal variation of cyanotoxins in freshwater ecosystems. Trends in Environmental Analytical Chemistry, 26, e00091

[26]  Nanusha, M. Y., Krauss, M., Schönsee, C. D., Günthardt, B. F., Bucheli, T. D. & Brack, W. (2020). Target screening of plant secondary metabolites in river waters by liquid chromatography coupled to high-resolution mass spectrometry (LC–HRMS). Environmental Sciences Europe, 32,142

[25] Picardo, M., Núñez, O. & Farré, M. (2020). Suspect and Target Screening of Natural Toxins in the Ter River Catchment Area in NE Spain and Prioritisation by Their Toxicity. Toxins ,12(12), 752

[24] Kisielius V., Hama, J.R., Skrbic, N., Hansen, H.C.B., Strobel, B.W. & Rasmussen, L.H. (2020). The invasive butterbur contaminates stream and seepage water in groundwater wells with toxic pyrrolizidine alkaloids. Scientific Reports, 10, 19784

[23] Hama, J.R. & Strobel, B.W. (2020). Natural alkaloids from narrow-leaf and yellow lupins transfer to soil and soil solution in agricultural fields. Environmental Sciences Europe, 32, 126

[22] Skrbic, N., Pedersen, A., Christensen, S. C. B., Hansen, H. C. B. & Rasmussen, L. H. (2020). A novel method for determination of the natural toxin ptaquiloside in ground and drinking water. Water12(10), 2852

[21] Nanusha, M.Y., Krauss, M. & Brack, W. (2020). Non‑target screening for detecting the occurrence of plant metabolites in river waters. Environmental Sciences Europe, 32, 130

[20] García-Jorgensen, D. B., Hansen, H. C. B., Abrahamsen, P. & Diamantopoulos, E. (2020). A novel model concept for modelling the leaching of natural toxins: results for the case of ptaquiloside. Environmental Science: Processes & Impacts22(8), 1768-1779

[19] Schneider, M., Rataj, R., Kolb, J. F. & Bláha, L. (2020). Cylindrospermopsin is effectively degraded in water by pulsed corona-like and dielectric barrier discharges. Environmental Pollution, 266 (2), 115423

[18] Schneider, M. & Bláha, L. (2020). Advanced oxidation processes for the removal of cyanobacterial toxins from drinking water.  Environmental Sciences Europe, 32, 94

[17] Natumi, R. S. & Janssen, E. M.-L. (2020). Cyanopeptide co-production dynamics beyond microcystins and effects of growth stages and nutrient availability. Environmental Science & Technology, 54(10), 6063–6072

[16] Jones, M. R., Pinto, E., Torres, M. A., Dörr, F., Mazur-Marzec, H., Szubert, K., Tartaglione, L.,  Dell'Aversano, C., Miles, C. O., Beach, D. G., McCarron, P., Sivonen, K., Fewer, D. P.,  Jokela, J. & Janssen, E. M.-L. (2020). Comprehensive database of secondary metabolites from cyanobacteria. BioRxiv

[15] Filatova, D., Núñez, O. & Farré, M. (2020). Ultra-Trace Analysis of Cyanotoxins by Liquid Chromatography Coupled to High-Resolution Mass Spectrometry. Toxins, 12(4), 247

[14] Egli, C. M., Natumi, R. S., Jones, M. R. & Janssen, E. M.-L. (2020). Inhibition of Extracellular Enzymes Exposed to Cyanopeptides. Chimia (Aarau)74(3), 122–128

[13] Günthardt, B. F., Schönsee, C. D., Hollender, J., Hungerbühler, K., Scheringer, M. & Bucheli, T. D. (2020). “Is there anybody else out there?” – First Insights from a Suspect Screening for Phytotoxins in Surface Water. CHIMIA, 74(3), 129–135

[12] Schönsee, C. D. & Bucheli, T.D. (2020). Experimental Determination of Octanol–Water Partition Coefficients of Selected Natural Toxins. Journal of Chemical & Engineering Data, 65(4), 1946-1953

[11]  Liang, X., Nielsen, N.P. & Christensen, J. H. (2020). Selective pressurized liquid extraction of plant secondary metabolites: Convallaria majalis L. as a case. Analytica Chimica Acta: X, 4, 100040

[10] Brozman, O., Kubíčková, B., Babica, P. & Labohá, P. (2020). Microcystin-LR does not alter cell survival and intracellular signaling in human bronchial epithelial cells. Toxins, 12(3), 165

[9] Schneider de Oliveira, L.G., Boabaid F.M., Kisielius V., Rasmussen L.H., Buroni F., Lucas M., Schild C.O., Lopez F., Machado M. & Riet-Correa F. (2020). Hemorrhagic diathesis in cattle due to consumption of Adiantopsis chlorophylla (Swartz) Fée (Pteridaceae). Toxicon: X, 5, 100024

[8] Kisielius, V., Lindqvist, D.N.,  Thygesen, M.B., Rodamer, M., Hansen, H.C.B. & Rasmussen, L.H. (2020). Fast LC-MS quantification of ptesculentoside, caudatoside, ptaquiloside and corresponding pterosins in bracken ferns. Journal of Chromatography B, 1138, 121966

[7] Hama, J.R. & Strobel B. W. (2019). Pyrrolizidine alkaloids quantified in soil and water using UPLC-MS/MS. RSC Advances, 9, 30350-57

[6] Aranha PCdR, Rasmussen L.H., Jensen HME, Hansen, H.C.B. & Friis C. (2019). Fate of ptaquiloside—A bracken fern toxin—In cattle. PLoS ONE 14(6): e0218628. 

[5] Kubíčková, B.; Babica, P.; Hilscherova, K. & Šindlerová, L. (2019). Effects of Cyanobacterial Toxins on the Human Gastrointestinal Tract and the Mucosal Innate Immune System. Environmental Sciences Europe, 31, 31

[4] Janssen, E.M.-L. (2019). Cyanobacterial peptides beyond microcystins – A review on co-occurrence, toxicity, and challenges for risk assessment, Water Research, 151, 488-499

[3] Kubíčková, B., Labohá, P., Hildebrandt, J.-P., Hilscherová, K. & Babica, P. (2019). Effects of cylindrospermopsin on cultured immortalized human airway epithelial cells. Chemosphere, 220, 620-628 

[2] Picardo, M., Filatova D., Núñez, O. & Farré, M. (2019). Recent advances in the detection of natural toxins in freshwater environments. Trend on Analytical Chemistry. 112, 75-86

[1] Bucheli, T.D., Strobel B.W. & Hansen H.C.B. (2018). Personal Care Products Are Only One of Many Exposure Routes of Natural Toxic Substances to Humans and the Environment. Cosmetics, 5(1), 10






The project was funded by:

Project: NaToxAq
Principal investigator: Hans Chr. Bruun Hansen
Start: 1 January 2017
End: 31 January 2020