Investigating Potamopyrgus antipodarum as suitable test species for ecotoxicology testing of surface water

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1 Investigating Potamopyrgus antipodarum as suitable test species for ecotoxicology testing of surface water Maita Subba, PhD candidate CAPIM Research Summit, 25 th August 2017

2 Potamopyrgus antipodarum Aquatic freshwater snails. Ovoviviparous and parthenogenetic prosobranch molluscs. GABI, 2016

3 P. antipodarum Shell height- 12 mm (New Zealand); 4 to 6 mm (invaded land). Colour-Brown to light brown, black. Starts reproducing at 3.5 mm (ca. 3-6 months). Diagram of an adult female Potamopyrgus antipodarum. O= ovary; E= unshelled embryos; Bp=Brood pouch; Ews= shelled embryo and Op= operculum

4 P. antipodarum Feeds on algae, bacteria, and detritus from surface of sediment, plants, and stones. Tolerant to various environmental stressors. Strong operculum. Operculum

5 P. antipodarum They are euryhaline.

6 Why P. antipodarum? Ecotoxicological tests under laboratory testing, experimental streams, in situ experiments, for single substance to multiple substances, from wastewater to river water, in sediments. Suitable species to test environmentally relevant concentration of toxic compounds and endocrine disrupting compounds (EDCs) in water and sediment.

7 Why P. antipodarum? Sieratowicz et al., 2011

8 Why P. antipodarum? Recommended for reproduction test by Organisation for Economic Co-operation and Development (OECD) guideline. Suitable test species to assess effect of EDCs on invertebrates. Unshelled embryos Shelled embryos d%20wnt%20comments_clean.pdf

9 EDC studies on P. antipodarum Research Endocrine effects of contaminated sediments on the freshwater snail Potamopyrgus antipodarum in vivo and in the cell bioassays in vitro Authors Mazurová et al In situ biomonitoring of freshwater quality using the New Zealand mudsnail Potamopyrgus antipodarum (Gray) exposed to waste water treatment plant (WWTP) effluent discharges Gust et al Introduction: The Ecological Relevance of Chemically Induced Endocrine Disruption in Wildlife Reproductive toxicity of bisphenol A and cadmium in Potamopyrgus antipodarum and modulation of bisphenol A effects by different test temperature Sensitivity of New Zealand mudsnail Potamopyrgus antipodarum (Gray) to a specific aromatase inhibitor Stimulated embryo production as a parameter of estrogenic exposure via sediments in the freshwater mudsnail Potamopyrgus antipodarum Jobling et al Sieratowicz et al., 2011 Gust et al Duft et al., 2003 Prosobranch snails as test organisms for the assessment of endocrine active chemicals an overview and a guideline proposal for a reproduction test with the freshwater mudsnail Potamopyrgus antipodarum In situ effects of urban river pollution on the mudsnail Potamopyrgusantipodarum as part of an integrated assessment The antimicrobial agents triclocarban and triclosan as potent modulators of reproduction in Potamopyrgus antipodarum (Mollusca: Hydrobiidae) Duft et al Zounkova et al Geiß et al In situ deployment of P. antipodarum in cages. (Mossop et al. 2013) THE ANTIMICROBIAL TRICLOCARBAN STIMULATES EMBRYO PRODUCTION IN THE FRESHWATER MUDSNAIL POTAMOPYRGUS ANTIPODARUM Giudice and young, 2010.

10 P. antipodarum studies in Australia. Study Test duration Endpoints Reference Origin of P. antipodarum in Australia. - Origin of P. antipodarum (W. F. Ponder, 1988) Density, population structure and 2 y Density, population structure and (E. S. G. Schreiber et al., 1998) fecundity. fecundity. Effect of high density P. antipodarum on 6 d Density of colonizing invertebrates (E. Schreiber, Lake, & Quinn, 2002) native species. Forecasting distribution of P. antipodarium in Australia and North America using Genetic Algorithm for Rule-set Production (GARP). - Potential spread of P. antipodarium in Australia and North America. (S. Loo et al., 2007) Effect of spatial and temporal change in water velocity on population of P. antipodarum. Distribution of P. antipodarum, Physa acuta and Leptophlebiidae in streams with different level of urban development. Impact of wastewater discharges on macroinvertebrate communities. 7 d before flood and 3, 6 and 8 d after flood. Density of P. antipodarum before and after flood. 3 m Density of P. antipodarum affected by urban development (Kefford & Lake, 1999) (Shield et al., 2014) 48 h- (novel bio-assay) Immobility (Sullivan, Wright, Renshaw, & Wilks, 2014) Deployment of P. antipodarum at sites in cages Interaction between P. antipodarum and Austropyrgus angasi under model predicted current and future temperature conditions. Distribution of P. antipodarium in streams in relation to flow variability, human activities and water quality Comparing the fauna composition in exposed and sheltered shore and between seasons of lakes and streams in one locality. To assess the presence of EDCs in a creek. Use Geographical Information Systems (GIS) to explain the spread of P. antipodarum in Victoria, Australia. 42 d Survival (Kellar et al., 2014) 1-3 w Growth and survival (Sardina, Beringer, Roche, & Thompson, 2015) April, 1994 and June 1994 Distribution of P. antipodarium (E. S. G. Schreiber, Quinn, & Lake, 2003) Distribution of fauna in summer and winter and (G. Quinn, Lake, & Schreiber, 1996) 6 w Shell and aperture height; survival; (Mossop et al., 2013) shelled and unshelled embryos. - Invasion of P. antipodarum (S. E. Loo, Keller, & Leung, 2007)

11 Aim of my Thesis Aim 1: Study the life history of P. antipodarum under laboratory conditions. Aim 2: Develop standard method for acute tests. Aim 3: Develop standard method for chronic tests. Aim 4: Deploy the snails in the field.

12 Aim: Develop standard method for acute tests.

13 Methods Test compound: Zinc. Static bioassay-water only. 10 snails/replicate. Species- P. antipodarum (> 3.5 mm) Duration- 96-h Treatment Zinc Conc. Replicates T1 2.5mg/L 3 T2 5mg/L 3 T3 10mg/L 3 T4 20mg/L 3 T5 40mg/L 3 Control 0mg/L 3

14 Methods cont. Endpoint- mortality; behaviour-normal, distressed, retracted. Snails put in reconstituted water for 24h- to check mortality. Test conditions: 16 ± C. Light:dark-16:8 h. DO: > 60%, Conductivity: 770 ± 100 µs/cm.

15 Results 24-h Reading 12 Avg. No. of snails (3 reps) N D R 0 T1 T2 T3 T4 T5 C Treatments

16 Results h Reading Avg No. of Snails(3reps) T1 T2 T3 T4 T5 Control Treatments N D R

17 Results 72-h, Reading 12 Avg No. of snails (3 reps) T1 T2 T3 T4 T5 Control Treatments N D R

18 Results 96h- Reading 12 Avg. No. of snails (3 reps) T1 T2 T3 T4 T5 Control Treatments N D R

19 Results 12 Mortality after 24-h in reconstituted water Avg. No. of snails (3reps) T1 T2 T3 T4 T5 Control Mortality A D

20 Conclusions Snails are sensitive to Zn exposure. May not be a sensitive species to test for low conc. of Zn in the environment. Studying their behaviour could be an important endpoint in monitoring aquatic pollution. Potential passive sampler.

21 Thank you! Questions?