Guest Lecture 1: Investigating the exposure accumulation and reproductive effects to wild birds of per-and polyfluoroalkyl substances

Which TA gave this guest lecture?

Kailee Hopkins

What are the names of the chemical substances at the heart of this research?

Per-and polyfluoroalkyl substances (PFAS) and Perfluoroalkyl acids (PFAAS) which then under this umbrella include Perfluorocarboxylic acis (PFCAs) and Perfluorosulfonic acids (PFSAs)

What were the overall objectives of the entire Phd research?

Characterize the exposure, accumulation and potential toxic effects of perfluoroalkyl acids (PFAAs) and precursor compounds in avian species.

What were the three sub-objectives

1. Investigate tissue distribution and WWTP sources of PFAAs exposure

2. Sources and movement of PFAs in the food web of the tree swallows

3. Effects of PFAAs on reproductive measures

More info on Tree Swallows and why they were chosen as the organism of study

(Tachycineta bicolor)

• Aerial insectivores

• Wide range distribution in North America

Why?

• Colony nesters

• Large clutch sizes

• Localized foraging (200m radius)

Location of the study

Southern Ontario, Canada

What is the title and objectives of the first chapter

Exposure and Accumulation of SC and LC-PFAAs

1. Characterize PFAA exposure in mid-trophic passerines, e.g. tree swallows

2. Evaluate WWTPS as a point source of PFAAs for wild birds

3. Investigate possible ecological and biological influences on PFAA accumulation

What was used for analysis in first chapter

• Eggs

• Chick carcasses

• Chick livers

What is the title and objectives of the second chapter

Characterizing PFAS Movement in a Complex Food Web

1. Characterizethe aquatic-terrestrial food web structure

2. Assess concentrations and profiles of PFAS

3. Calculate bioaccumulation and biomagnification factors

What was used in the sample collection in the second chapter

• Air

• Surface water

• Sediment

• Aquatic macroinvertebrates

• Terrestrial macroinvertebrates

• Tree Swallow nestlings

How can we assess dietary patterns in the aquatic terrestrial food web?

Fatty Acids (FAs)

• Major componet of lipids found in plant and animal tissues

  • Can be used to trace food web origins

What is the title and objectives of the third chapter

Reproductive toxicity of perfluoroalkyl acids in an aerial insectivore

1. Identify anhy PFAA influence(s) on reproductive measures in a mid-trophic passerine

2. Evaluate the influence of PFAAs on reproductive outcomes relative to legacy environmental contaminants with known reproductive toxicity, specfically PCBS, PBDEs, OCPs and Hg

What does WWTP stand for

Wastewater Treatment Plant

Final Conclusions from chapters 1-3

1. PFAA distribution patterns largely similar among eggs > chicks

   • WWTPs are a significant discharge source of PFAAs to wildlife

2. PFAS transfer is complex in this aquatic-terrestrial food web

   • Some PFAS bioaccumulate and some biomagnify, including PFOS and some LC-PFCAs

3. PFOS and some LC-PFCAs associated with reproductive parameters

   • PFAAs has a similar influence on fledging success as PCBS and PBDEs

Potential Toxicity of PFDA

1. PFDA accumulates in various tree swallow tissues and had the second-highest concentration in eggs following PFOS

2. PFDA bioaccumulates and biomagnifies through tree swallow food web

3. PFDA exposure is associated reproductive parameters like incubation period, hatching and fledging success

Next steps for her research?

Investigating the toxicity of PFDA using Japanese quail (Coturnix japonica) as a model organism

Objectives:

1. Investigate the toxic effects of PFDA to developing Japanese quail embryos when exposed in vivo

2. Link same individual in vivo and in vitro effects of PFDA exposure

Future Directions: Lab based studies to further investigate associations

What does this kind of research do?

Supports evidence-based contaminant regulation