W. Tyler Mehler PhD Student Research Summit 18.8.2016 Development of freshwater whole-sediment toxicity identification evaluation (TIE) techniques for use in aquatic systems in Australia W. Tyler Mehler PhD Student Research Summit 18.8.2016

Clean Water Act and WET Testing 1984: “Whole Effluent Toxicity” test and Chemistry of “Priority Pollutants” Required Limitation in defining causality of toxicity: All Chemicals Cannot be Accounted for Potential for Complex Mixtures “Toxicity” Approach

Late 80s to early 90s – TRE/TIE guidance developed in Duluth, MN Development of TIE Late 80s to early 90s – TRE/TIE guidance developed in Duluth, MN

What is a TIE? Toxicity Identification Evaluation = TIE 10% Mortality Conduct Toxicity Test Adjust water for organics 70% Mortality Organic Contaminated Water No Change Adjust water for ammonia Conduct Toxicity Test The same Organic Contaminated Water Adjust water for metals Conduct Toxicity Test No Change

Matrix Choice Problems: Overlying Water & Pore Water Issues with surface water TIEs: Many contaminants are hydrophobic, contaminants are not in surface water Pore water Sediment grain Issues with pore water TIEs: Bioavailability Ingestion Water quality parameters Environmental Realistic? usgs.gov

Add organics amendment Sediment TIEs 10% Mortality Conduct Toxicity Test Add organics amendment Organic Contaminant 70% Mortality No Change Add ammonia amendment Conduct Toxicity Test Organic Contaminant Organic Contaminant Add metals amendment Conduct Toxicity Test No Change Organic Contaminant

TIE Method ?? Test Species: Chironomus tepperi Austrochiltonia subtenuis Spiked Contaminants: Ammonia Copper Permethrin Endpoints: Mortality Growth (via dry weight) ??

1.54 NA 3.92 TIE Method for Ammonia ?? Test Species: Chironomus tepperi Austrochiltonia subtenuis Spiked Contaminants: Ammonia Copper Permethrin Endpoints: Mortality Growth (via dry weight) NA 3.92 ??

TIE Method for Cationic Metals 1.70 Test Species: Chironomus tepperi Austrochiltonia subtenuis Spiked Contaminants: Ammonia Copper Permethrin Endpoints: Mortality Growth (via dry weight) 3.15 5.23 ??

TIE Method for Permethrin 4.52 Test Species: Chironomus tepperi Austrochiltonia subtenuis Spiked Contaminants: Ammonia Copper Permethrin Endpoints: Mortality 3.02 Growth (via dry weight) In Progress ??

TIE Method for Permethrin Test Species: Chironomus tepperi “When this technique was explored with freshwater organisms in 10-day tests (measuring survival and growth), some problems with reduced growth and/or survival occurred at higher levels of charcoal addition.” – US EPA TIE guidance (2007) Austrochiltonia subtenuis Spiked Contaminants: Ammonia Copper Permethrin Endpoints: Mortality Growth (via dry weight) ??

Aim #2: Understanding the limitations of charcoal-based amendments for TIE purposes. “…we have tended to emphasize the growth endpoint in TIE work with C. dilutus and would recommend using it even if the sediment causes mortality of C. dilutus at higher concentrations. In selecting the sediment dilution to be used in a TIE based on C. dilutus growth, we generally select a dilution that exerts a strong growth effect (e.g. 75% inhibition of growth) without causing substantial mortality.” – US EPA TIE guidance (2007) Maul et al. 2008

Resolving the Activated Carbon Issue Emergence Survival B a a a Growth (as a function of weight) is sediment-specific. Activated carbon at higher concentrations affected both weight and mean development. Emergence (and survival) not affected by additions of activated carbon. Is emergence more sensitive than growth for midges? 1 a 1 1 1,2 b b 1,2 2 C 1 1,2 1,2 1,2 a 2 a,b a a a 2 b Males Females

Next Steps on improving TIEs: Specific TIEs for novel chemicals that may not be removed by traditional means (i.e. Spinosad). Rapid TIE techniques (i.e. fish embryos). Application in field.

Folks at FilChem and Castle Mountain Zeolite Questions? Acknowledgements: CAPIM and Biosciences You Jing and Li Huizhen Michael Zammit Folks at FilChem and Castle Mountain Zeolite