Presentation for research conducted on AIM2 research project.

1. Investigating the Ecotoxicological Impacts of
Microplastics on New Zealand Native Species
Andrew Barrick, Mike Boundy Olivier Champeau & Louis Tremblay

2. 2
Aotearoa Impacts and Mitigation of
Microplastics: AIM2
• AIM2: distribution and impacts of microplastics
in New Zealand
• Distribution of plastics in sediment,
freshwater and coastal environments
• Determine the potential ecotoxicological
and environmental effects of microplastics

3. 3
>1 meter 5cm-5mm 5mm-0.1µm <1µm
Megaplastics Macroplastics Mesoplastics Microplastics Nanoplastics
>5cm
Plastic Ecotoxicity: A Question of Scale

4. 4
A Cocktail of Potential Ecotoxic
Effects
Antioxidant
Thermostabilizer
Antioxidant
Thermostabilizer
O2
O2 O2
Barrick A., Champeau O., Chatel A., Manier N., Northcott G., Tremblay L. 2021. Plastic additives: challenges in ecotox hazard assessment.
PeerJ. 10.7717/peerj.11300

5. 5
Tiered Ecotoxicity Testing Strategy
Will organisms
interact with
microplastics?
Are additives
inherently
toxic?
If prepared in
microplastics are
additives more toxic?
Are there chronic,
multigenerational
effects?
Mechanisms of
toxicity?
Oxidative Stress
Algae
Plastic
Tier I Tier II

6. 6
Test Species
• Broad geographic distribution
• “Easy” to culture & test
• High reproductive capacity
Copepods Green and Blue Mussels
• Mytilus galloprovincialis
• Recognized sentinel species
• International distribution
• Standardized testing approaches
• Perna canaliculus
• Significant commercial & cultural value
• Native comparator
• Broader ecological niche compared to blues
Algae
• Fast growth rate
• Easy to culture & test
• Standardized test

7. 7
Biological uptake of microplastics: Adults
1-5µm beads 22-27µm beads 43-53µm beads 75-90µm beads

8. 8
Biological uptake of microplastics: Nauplii
1-5µm beads 22-27µm beads 43-53µm beads 75-90µm beads

9. 9
Feeding Trials
-14000
-12000
-10000
-8000
-6000
-4000
-2000
0
1-5µm 22-27µm 43-54µm 75-90µm
Algal
Densities
Relative
to
Control
(cells/mL)
Copepod Feeding Rates
Algae + Microplastics
(1-5µm)
Microplastics
(1-5µm)

10. 10
Preliminary Additive Ecotoxicity
Plastic
Additive
Uses
Benzophenone UV-blocker
Dibutyl
phthalate
Plasticizer
Irgafos 168
Prevents plastic
degradation
Irganox 1010
Prevents plastic
degradation
Irganox 1076
Prevents plastic
degradation
Nylostab
Color booster, UV
blocker, Stabiliser
Tinuvin 770 Stabiliser
UV-234 UV-blocker
*
* Kurihara H., Asai T., Kat Shoiju, Ishimatsu A. 2008. Effects of elevated pCO2 on early development in the mussel Mytilus galloprovincialis.
Aquatic Biology. (4), 225-233). Doi: 10.3354/ab00109
Day 0 Day 7
Copepod Larval Development Test
Copepod Acute Toxicity Test
+ =
Mussel Embryotoxicity

11. 11
Preliminary Additive Ecotoxicity
* Kurihara H., Asai T., Kat Shoiju, Ishimatsu A. 2008. Effects of elevated pCO2 on early development in the mussel Mytilus galloprovincialis.
Aquatic Biology. (4), 225-233). Doi: 10.3354/ab00109
Copepod
Acute
LC(50) mg/L
Copepod
Chronic
EC(50) mg/L
Blue mussel
embryotoxicity
EC(50) mg/L
Benzophenone 1.51 4.17 16.74
Dibutyl
Phthalate
0.93 0.12 0.65
Irgafos 168 Completely Insoluble
Irganox 1010 >5 5.80 >5
Irganox 1076 >10 >10 >10
Nylostab Completely Insoluble
Tinuvin 770 6.28 2.63 0.48
UV-234 >15 >10 >15 <1mg/L: Very Toxic
1-10mg/L: Toxic
10-100 mg/L:
Moderately Toxic
>100 mg/L: Non-Toxic
>Exceeds Solubility

12. 12
Future Perspectives
• No effect ≠ not toxic
• Preparation of microplastics at
sizes needed is extremely
challenging
• Organic material as vectors of
additive accumulation?
• Sublethal endpoints to
discriminate between plastic
effect and additive effect
Thermostabilizer
Biofilm & Grazing
“Sorption”
Thermostabilizer

13. 13
Acknowledgements
• Tanja Wiles & Juliette Butler:
technical assistance
• Natsumi Nishikawa: maintenance
of copepod culture
• Tony Bui: refreshment of copepod
cultures
• Jaime Bridson: preparation of
microplastics