Theme Leader: Cristina A. Viegas

Short-term bioassays using simple experimental models alternative to animals are required to provide rapid previews of toxicity level in environmental samples’ monitoring. Our research in this field has focused on development and application of bioassays using the microbial eukaryotic model Saccharomyces cerevisiae for the assessment of potential toxicity of xenobiotics, namely pesticides (e.g., in soil leachates and surface runoff), synthetic dyes (e.g., in textile wastewaters) or chemicals released from construction materials. For this purpose, molecular indicators of xenobiotic toxicity disclosed from transcription profiling studies in S. cerevisiae have been exploited.

In another line of research, focus has been given to optimization of bacteria-based bioremediation strategies viewing fast clean-up of soils contaminated with the chlorinated s-triazine herbicides atrazine and terbuthylazine; these studies aim at minimizing herbicide mobilization into aquatic ecosystems via the terrestrial-water pathway, which can be environmentally relevant in worst-case situations of soil contamination (e.g., accidental spills and careless storage, mix/loading or disposal).

Our current projects within this subject include

  • Assessment of the potential detoxification achieved upon biological treatment of textile wastewaters, using yeast-based phenotypic and gene expression bioassays;
  • Evaluation of the ecotoxicological potential of currently used and innovative construction materials (related to possible release of deleterious compounds into leaching waters during production, disposal and/or recycling);
  • Optimization and examination of the efficacy of the soil bacterial strains Arthrobacter aurescens TC1 and Pseudomonas ADP as bioaugmentation bacteria in soil contaminated with the herbicidal active ingredient terbuthylazine.

Selected publications

Gil, Fátima N., Belli, G., Viegas, C.A., The Saccharomyces cerevisiae response to stress caused by the herbicidal active substance alachlor requires the iron regulon transcription factor Aft1p. Environmental Microbiology 19(2): 485-499, 2017.

Lourenço, Nídia D., Franca, R.D.G., Moreira, M. A., Gil, F.N., Viegas, C.A., Pinheiro, H.M., Comparing aerobic granular sludge and flocculent sequencing batch reactor technologies for textile wastewater treatment, Biochemical Engineering Journal, 104: 57-63, 2015.

Silva, Vera P., Moreira-Santos, M., Mateus, C., Teixeira, T., Ribeiro, R., Viegas, C.A., Evaluation of Arthrobacter aurescens strain TC1 as bioaugmentation bacterium in soils contaminated with the herbicidal substance terbuthylazine. PLoS ONE 10(12):e0144978, 2015.

Gil, Fátima N., Moreira-Santos, M., Chelinho, S., Pereira, C., Feliciano, J.R., Leitão, J.H., Sousa, J.P., Ribeiro, R., Viegas, C.A., Suitability of a Saccharomyces cerevisiae-based assay to assess the toxicity of pyrimethanil sprayed soils via surface runoff: Comparison with standard aquatic and soil toxicity assays, Science of the Total Environment 505: 161-171, 2015.

Gil, Fátima N., Becker, J.D., Viegas, C.A., Potential mechanisms underlying response to effects of the fungicide pyrimethanil from gene expression profiling in Saccharomyces cerevisiae, Journal of Agricultural and Food Chemistry, 62: 5237-5247, 2014.

External Collaborators

  • Matilde Moreira-Santos, Rui Ribeiro, Sónia Chelinho, José Paulo Sousa, Department of Life Sciences, University of Coimbra, Portugal
  • Jörg D Becker, Instituto Gulbenkian de Ciência, Portugal
  • Gemma Bellí, University of Lleida, Spain
  • José Silvestre, Inês Flores-Colen, Jorge de Brito, Department of Civil Engineering, Instituto Superior Técnico, Portugal


NanoMicroImpact – Impact of engineered nanoparticles and microplastics on textile wastewater treatment with aerobic granular sludge technology, funded by FCT (PTDC/AAGTEC/4501/2014; PI – Nídia Lourenço, BERG-iBB), May 2016 – April 2019

Aerobic granular sludge technology toward effective elimination of the azo dye hazard in textile wastewater treatment (PI – Nídia Lourenço, BERG-iBB; Funded by UID/BIO/04565/2013), July 2016 – December 2017.