OUTLINE. DDTs Pyrethroids

Transcription

1 OUTLINE u Why use passive sampling and what it tells us u Why do we care about the freely dissolved concentration (C free ) u Types of passive samplers and how they work u Preparing, deploying, recovering, and storing passive samplers u Analyzing passive sampler data u Summary u Focus on nonionic organic contaminants (no metals or polar organic contaminants) PAHs Furans PCBs PBDEs DDTs Pyrethroids Dioxins 24 th Annual NARPM Training Program 1 2

2 WHY USE PASSIVE SAMPLING AND WHAT IT TELLS US (1) Freely dissolved concentrations (C free ) of contaminants of concern (COC) in water around passive sampler Surrogate for bioavailable concentrations of COC Media Porewater (Interstitial Water) Water column Compare to Water Quality Criteria (WQC), other water quality standards, sediment guidelines or water-only toxicity data for exceedances (2) Concentration of COCs in passive sampler Good correlation with bioaccumulation by aquatic organisms Serve as surrogates for biomonitoring organisms Benthic and water column organisms 24 th Annual NARPM Training Program 2 3

3 WHY DO WE CARE ABOUT THE FREELY DISSOLVED CONCENTRATION (C FREE )? Kepone u For benthic organisms: What media is an effective surrogate for exposure to bioavailable chemicals? Sediment? Food? = Pore Water = Freely dissolved? u Adams et al. (1985) addressed this question Two Kepone-amended sediments (same levels) 1.5% and 12.3% Sediment organic carbon Freshwater midge (Chironomus tentans) Flow-through and static 14 day exposures Acute and chronic (growth) endpoints Exposure-response relationships Survival and growth versus exposure Chironomus tentans 24 th Annual NARPM Training Program 3 4

4 WHY DO WE CARE ABOUT THE FREELY DISSOLVED CONCENTRATION (C FREE )? 100 What media is an effective surrogate for exposure to bioavailable chemicals? Midge Survival (%) % Organic carbon/kg sediment (dry) 12.3 % Organic carbon/kg sediment (dry) Sediment Food Sediment Concentration (mg Kepone/Kg sediment (dry)) 24 th Annual NARPM Training Program 4 5

5 WHY DO WE CARE ABOUT THE FREELY DISSOLVED CONCENTRATION (C FREE )? Midge Survival (%) % Organic carbon/kg sediment (dry) 12.3 % Organic carbon/kg sediment (dry) What media is an effective surrogate for exposure to bioavailable chemicals? Sediment Food Porewater Porewater Concentration (µg Kepone/L Porewater) 24 th Annual NARPM Training Program 5 6

6 WHY DO WE CARE ABOUT THE FREELY DISSOLVED CONCENTRATION (C FREE )? Midge Survival (%) % Organic carbon/kg sediment (dry) 12.3 % Organic carbon/kg sediment (dry) What media is an effective surrogate for exposure to bioavailable chemicals? Sediment Food Freely Dissolved Freely Dissolved Concentration (C free ) (µg Kepone/L Porewater) 24 th Annual NARPM Training Program 6 6

7 WHY USE PASSIVE SAMPLING AND WHAT IT TELLS US u Measuring freely dissolved concentrations (C free ) in the porewaters and water column Why not continue to use conventional sampling methods? Some problems: Is Porewater there another sampling method for measuring the freely Centrifugation dissolved or squeezing concentrations porewater results in limited volumes (C free ) of Several artifacts including losses to filters and surfaces and contamination by contaminants? colloids and small particles reduce accuracy of analysis Collecting large volumes of porewaters is logistically challenging, scientifically dodgy and generally expensive Water Column Logistically and technically difficult to collect and extract large volumes of surface water Same artifacts as porewater collection Analytical detection limits are often not sufficiently low 24 th Annual NARPM Training Program 7 7

8 WHY USE PASSIVE SAMPLING AND WHAT IT TELLS US Is there another sampling method for measuring the freely dissolved concentrations (C free ) of contaminants? 24 th Annual NARPM Training Program 8 7

9 TYPES OF PASSIVE SAMPLERS AND HOW THEY WORK Atmosphere Water (C free ) Contaminated Sediments 24 th Annual NARPM Training Program 98

10 TYPES OF PASSIVE SAMPLERS AND HOW THEY WORK Polyethylene (PE) µm thick PE Polyoxymethylene (POM) 75 µm thick POM 24th Annual NARPM Training Program 109

11 TYPES OF PASSIVE SAMPLERS AND HOW THEY WORK fiber-optic cable 0.25 m cross-section SPMD 2.5 cm SPME triolien layer um thick polyethylene shell containing synthetic lipid triolien 2.5 cm Solid Phase Microextraction (SPME) Semi-Permeable Membrane Device (SPMD) 24 th Annual NARPM Training Program 1110

12 TYPES OF PASSIVE SAMPLERS AND HOW THEY WORK PCB molecule (C free form) Pore water Initial concentration of PCBs in passive sampler = 0 ng/g Passive Sampler (e.g., PE, POM, SPME) 24 th Annual NARPM Training Program 1211

13 TYPES OF PASSIVE SAMPLERS AND HOW THEY WORK Equilibrium Sampling Concentration (ng/g Passive Sampler) 0 30 Deployment Time (days) 24 th Annual NARPM Training Program 1312

14 TYPES OF PASSIVE SAMPLERS AND HOW THEY WORK Equilibrium Sampling Concentration (ng/g Passive Sampler) Freely Dissolved Concentration (C free ) C free = * = Equilibrium C Sampler K Sampler free 0 30 Deployment Time (days) 24 th Annual NARPM Training Program 1413

15 PREPARING, DEPLOYING, RECOVERING, AND STORING PASSIVE SAMPLERS Passive Sampler (PE or POM) (1) Solvent Cleaning (~24 hours) (2) Deployment and Recovery (~ 30 days) (3) Storage (-4 C wrapped in foil) (6) GC/MS Quantification and Data Analysis/Interpretation (5) Volume reduction (~ 1 hour) (4) Solvent Extraction (48 hours) 24 th Annual NARPM Training Program 1514

16 PREPARING, DEPLOYING, RECOVERING, AND STORING PASSIVE SAMPLERS PE POM Water Column Deployment PE SPME (in copper mesh envelope) Stainless steel ring Fish trap (MIT, NHEERL & URI) (NHEERL & Brown U) 24th Annual NARPM Training Program 1615

17 PREPARING, DEPLOYING, RECOVERING, AND STORING PASSIVE SAMPLERS Water Column Deployment 24 th Annual NARPM Training Program 1716

18 SPME (in protective syringe) PREPARING, DEPLOYING, RECOVERING, AND STORING PASSIVE SAMPLERS Porewater Deployment Copper tubing housing SPME (inside stainless steel tube) (SCCWRP) (Technical U Denmark) SPME (in protective syringe) (Texas Tech U) 24 th Annual NARPM Training Program 1817

19 PREPARING, DEPLOYING, RECOVERING, AND STORING PASSIVE SAMPLERS Porewater Deployment (MIT) (MIT) PE or POM (in aluminum frame) PE or POM (in aluminum frame) 24 th Annual NARPM Training Program 1918

20 PREPARING, DEPLOYING, RECOVERING, AND STORING PASSIVE SAMPLERS Porewater Deployment 24 th Annual NARPM Training Program 2019

21 ANALYZING PASSIVE SAMPLER DATA u Calculate contaminant freely dissolved concentration (C free ) (ng/ ml): C free = C Sampler Sampler free u Commercial or research laboratory Measured concentration of contaminants in the passive sampler (C Sampler ) (ng/g) K u Guidance documents and scientific literature Passive sampler-free partition coefficient (K Sampler-free ) (ml/g) 24 th Annual NARPM Training Program 2120

22 ANALYZING PASSIVE SAMPLER DATA u In many cases, the passive sampler will not achieve equilibrium with the aquatic systems (e.g., COCs) C C = free free ( C = / Sampler f K eq ) K Sampler Sampler free free u Several approaches for calculating fractional equilibrium (f eq ) First order model Sampling rate model Diffusion model u Simple to operate spreadsheets and graphical user interfaces (GUIs) available to perform these (complicated) calculations 24 th Annual NARPM Training Program 221

23 SUMMARY u Passive sampling provides data on: u u Freely dissolved concentrations (C free ) of COCs Potential for COC bioaccumulation u Approach operates based on the well-understood principles of equilibrium partitioning and sampling u Preparation, deployment, recovery and storage are no more complicated than current contaminant sampling methods u Analysis of passive sampler data is becoming increasingly simpler u Possible to achieve greater scientifically-robustness, logistical simplicity, and more cost-effectiveness 24 th Annual NARPM Training Program 2322

24 SUMMARY u Useful documents Passive_SamplerSAMS_Final_Camera_Ready_-_Jan_2013.pdf RB%20ESB%202012final_2.pdf Society of Environmental Toxicology and Chemistry journal: Integrated Environmental Assessment and Management 2014 Series (Six papers on passive sampling) EPA/600/R-16/357 Laboratory, Field, and Analytical Procedures for Using Passive Sampling in the Evaluation of Contaminated Sediments: User s Manual Available Winter 2017 February 2017 Final Web Version (1.0) 24 th Annual NARPM Training Program 2423

25 Thank you! 24 th Annual NARPM Training Program 2524