Mixtures of Chemical Pollutants at European Legislation Safety Concentrations : How Safe Are They ?

Raquel N. Carvalho (1) , Augustine Arukwe , Selim Ait-Aissa (2) , Anne Bado-Nilles (2, 3) , Stefania Balzamo (4) , Anders Baun , Shimshon Belkin , Ludek Blaha (5) , François Brion (2) , Daniela Conti (4) , Nicolas Creusot (2) , Yona Essig (6) , Valentina E.V. Ferrero (1) , Vesna Flander-Putrle , Maria Furhacker , Regina Grillari-Voglauer , Christer Hogstrand (6) , Adam Jonas (5) , Joubert B. Kharlyngdoh , Robert Loos (1) , Anne-Katrine Lungebye , Carina Modig , Per-Erik Olsson , Smitha Pillai , Natasa Polak (6) , Monica Potalivo (4) , Wilfried Sanchez (2, 3) , Andrea Schifferli (7) , Kristin Schirmer (7, 8) , Susanna Sforzini , R. Sturzenbaum, Stephen (6) , Liv Softeland , Valentina Turk , Aldo Viarengo , Inge Werner (7) , Sharon Yagur-Kroll , Radka Zounkova (5) , Teresa Lettieri (1)

1 IES - JRC Institute for Environment and Sustainability
2 INERIS - Institut National de l'Environnement Industriel et des Risques
3 SEBIO - Stress Environnementaux et BIOsurveillance des milieux aquatiques
4 ISPRA - Istituto Superiore per la Protezione e la Ricerca Ambientale
5 RECETOX / MUNI - Research Centre for Toxic Compounds in the Environment [Brno]
6 King‘s College London
7 EAWAG - Swiss Federal Insitute of Aquatic Science and Technology [Dübendorf]
8 EPFL - Ecole Polytechnique Fédérale de Lausanne

The risk posed by complex chemical mixtures in the environment to wildlife and humans is increasingly debated, but has been rarely tested under environmentally relevant scenarios. To address this issue, two mixtures of 14 or 19 substances of concern (pesticides, pharmaceuticals, heavy metals, polyaromatic hydrocarbons, a surfactant, and a plasticizer), each present at its safety limit concentration imposed by the European legislation, were prepared and tested for their toxic effects. The effects of the mixtures were assessed in 35 bioassays, based on 11 organisms representing different trophic levels. A consortium of 16 laboratories was involved in performing the bioassays. The mixtures elicited quantifiable toxic effects on some of the test systems employed, including i) changes in marine microbial composition, ii) microalgae toxicity, iii) immobilization in the crustacean Daphnia magna, iv) fish embryo toxicity, v) impaired frog embryo development, and vi) increased expression on oxidative stress-linked reporter genes. Estrogenic activity close to regulatory safety limit concentrations was uncovered by receptor-binding assays. The results highlight the need of precautionary actions on the assessment of chemical mixtures even in cases where individual toxicants are present at seemingly harmless concentrations.

Keywords: BIOASSAYS; EFFECTS; MIXTURES; ECOTOXICOLOGY; BIOMARKERS

Domains: Ecotoxicology

Raquel N. Carvalho, Augustine Arukwe, Selim Ait-Aissa, Anne Bado-Nilles, Stefania Balzamo, et al.. Mixtures of Chemical Pollutants at European Legislation Safety Concentrations : How Safe Are They ?. Toxicological Sciences, 2014, 141 (1), pp.218-233. ⟨10.1093/toxsci/kfu118⟩. ⟨ineris-01855038⟩