Nanoparticles and the environment: behaviour, ecotoxicity and fate

Transcrição

1 Nanoparticles and the environment: behaviour, ecotoxicity and fate Susana Loureiro Dept. de Biologia and CESAM, Universidade de Aveiro

2 ENVIRONMENT characteristics of nanomaterials and nanoparticles that can be changed by industry in order to produce SAFE SUSTAINABLE ACADEMIA NANO INDUSTRY STAKEHOLDERS

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4 Tools for the adaptation of the existing chemical regulatory frameworks or other management systems to the specific properties of manufactured nanomaterials include: I. Testing Preliminary Review of OECD Test Guidelines for their Applicability to Manufactured Nanomaterials [ENV/JM/MONO(2009)21] Guidance on Sample Preparation and Dosimetry for the Safety Testing of Manufactured Nanomaterials [ENV/JM/MONO(2012)40] II. Exposure Assessment Identification, Compilation and Analysis of Guidance Information for Exposure Measurement and Exposure Mitigation: Manufactured Nanomaterials [ENV/JM/MONO(2009)15] III. Risk Assessment Important Issues in Risk Assessment of Manufactured Nanomaterials [ENV/JM/MONO(2012)8]

5 nanoall.blogspot.com skincare.allwomenstalk.com

6 Emission Scenarios Exposure Scenarios Representative dose Shower % of applied dose down drain. Form of ENP? Free, aggregated, associated with biological material? Loss in secondary treatment? River exposure? Cosmetic nanotechnology product Potential sewer transformation? Loss in primary, or secondary settlement tanks? Toxicity to aquatic organisms Toxicity to Soil organisms Sludge (to land) Fig. 1. Schematic illustrating key issues concerning the disposal fate and environmnetal relase pathways of an example down the drain nanotechnology product (e.g. ZnO ENP containing sunscreen.

7 Characterization relevance for Exposure assessment and Effects Agglomeration State Concentration Shape Surface Speciation Surface Charge Size Surface Functionality Size Distribution Porosity / Surface Area Composition Structure / Crystallinity Hassellöv and Kaegi, 2009

8 Dissolution Science of The Total Environment 438,

9 Hassellöv and von der Kammer, SETAC short course 2009

10 Environmental factors ph Surface charge (aggregation), ligands; Ionic strength Aggregation Dissolved organic matter Soil pore water and surface waters Surface changes Transmit negative charges Can work as natural stabilizer of nanoparticles against aggregation.

11 Diversity of the aquatic ecosystems in Europe Class 1&2- represent low ionic strength, low divalent ions, low carbonate: (high stability) Class 5&6- represent high ionic strength, high divalent ions, high carbonate: (low stability) Martin Hasselhov

12 R&D with Industry Safe and Sustainable NM/NP

13 Approaches Ag NP COATING DISSOLUTION CONSIDER THE TOXICITY OF THE COATING ALONE Consider Ag NP, Ag+, Ag complexes, in time AGGLOMERATION AGGREGATION Consider the behaviour in the exposure media

14 AgNP in tap water (Aveiro, Portugal) Fresh After 48h

15 Soil matrix- more complex matrix Unspiked soil Ag NP clusters Aggregates nm single particles 5-8 nm TEM images of unspiked (A) and Ag NP spiked (nominal concentration 800 mg Ag/kg) (B, C and D) Lufa 2.2 soil. It was possible to detect Ag NP clusters (B), aggregates of nm (C), and single particles of 5-8 nm (D).

16 Relate Exposure to Effects cell culture temperature (after irradiating cells with internalized PEG-nGO) cell membrane broken by heat Environmental effects?????

17 Representative dose Shower % of applied dose down drain. Form of ENP? Free, aggregated, associated with biological material? Loss in secondary treatment? River exposure? Cosmetic nanotechnology product Potential sewer transformation? Loss in primary, or secondary settlement tanks? Toxicity to aquatic organisms Toxicity to Soil organisms Aquatic compartment Sludge (to land) Fig. 1. Schematic illustrating key issues concerning the disposal fate and environmnetal relase pathways of an example down the drain nanotechnology product (e.g. ZnO ENP containing sunscreen. Laser Irradiation High % of energy from the sun on the earth surface is infrared (IR)

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19 Micro-algae Similar toxicity to AgNP and AgNO 3

20 Concentration-response relationship for the combination of Ag-NPs and AgNO 3 showing a dose ratio dependence for the survival of Daphnia magna. with time increase of dissolution increase of toxicity

21 How to use this information?? Deriving PNECs for Risk Assessment

22 PREDICTED ENVIRONMENTAL CONCENTRATION

23 Shower % of applied dose down drain. Form of ENP? Free, aggregated, associated with biological material? Loss in secondary treatment? Representative dose River exposure? Cosmetic nanotechnology product Mapping risk Potential sewer transformation? Loss in primary, or secondary settlement tanks? Toxicity to aquatic organisms Toxicity to Soil organisms Sludge (to land) Fig. 1. Schematic illustrating key issues concerning the disposal fate and environmnetal relase pathways of an example down the drain nanotechnology product (e.g. ZnO ENP containing sunscreen. RQ PEC i PNEC i

24 Obrigada pela atenção! Para mais informações: Susana Loureiro