2017 perspective (and opinion) on experimental framework for - - PowerPoint PPT Presentation

▶
2017 perspective and opinion on experimental framework
SMART_READER_LITE
LIVE PREVIEW

2017 perspective (and opinion) on experimental framework for - - PowerPoint PPT Presentation

Jul 09, 2023 302 likes •657 views

2017 perspective (and opinion) on experimental framework for microplastic monitoring Martin Hassellv Department of Marine Sciences, University of Gothenburg Martin.hassellov@marine.gu.se Content Current end-user need of environmental

slide-1
SLIDE 1

2017 perspective (and opinion) on experimental framework for microplastic monitoring

Martin Hassellöv Department of Marine Sciences, University of Gothenburg Martin.hassellov@marine.gu.se

slide-2
SLIDE 2

Content

  • Current end-user need of environmental

surveillance of microplastic

  • Perspective on gap in knowledge or

aggreement on definitions and classifications

  • Harmonization issues of sampling
  • Harmonization issues of the analytical

procedures

  • Examples from our research activities
  • Perspectives on pressing research needs
slide-3
SLIDE 3

Monitoring

  • link to sources
  • baseline and trends, link to measures
  • Where to measure?
slide-4
SLIDE 4
  • Standing stock=f(input+ import+macrofragmentation-

nanofragmentation-sedimentation-beaching-uptake,…)

  • Variability= f(precipitation, sun, temp, wind, seasonal activities,…)
  • Sediments more stable standing stock, but too stable…?

(bioturbation, trawling, dredging,…)

Water compartment - very dynamic

slide-5
SLIDE 5

Perspective on gap in aggreement on definitions and classifications

  • Nota Bene Litter -not just plastics & microlitter not just

microplastics

  • NB Plastics is not just variations of the same thing

– Large variation of chemical, physical and biological properties – Very different environmental conseqeunces (fate, half-life, effects)

  • Large focus on size spectra

– Agreement on size is important but not all

  • NB Buoyancy for example, is a function of size, shape and

composition (and also weathering and fate processes)

slide-6
SLIDE 6

Size spectra

  • Arbitrary limits put on a

size continuum

  • Upper limit – 5mm or

1mm?

  • Lower limit

– Poorly defined – Operational

  • JPI Oceans goal: 1µm
  • Nanoplastics

– New concept – 1nm-1µm / 1-100nm – Studies on nanoplastics largely lacking

slide-7
SLIDE 7

Plastic Size Continuum – what shall we measure?

NanoPlastics MicroPlastics MesoPlastics MacroPlastics Fragmentation? Proxy for? Proxy for?

High surface area, high particle numbers low numbers, large mass, particle volume Comprehensive, advanced analysis required simpler analysis required Cellular uptake, biomagnification, biochemical ingestion physical effects entanglement Diffusing, Colloidal behavior, bioavailable? slowly settling rapid floatation or rapid sinking

Primary particles inputs

slide-8
SLIDE 8

Sampling considerations – water compartment

  • No single methods can sample from macro to

nano, not even the entire microplastic size ranges

– Different volumes (sampling effort) needed for statistical power within each size fraction – Clogging effects – Sea surface microlayer vs pelagic – …

  • So choices need to be made, and several methods

combined

slide-9
SLIDE 9

Manta-trawl

  • Floating litter >300µm
  • Conventional wide, 1-2 knop
  • High-Speed, narrow, up to 8 knots
  • Self-planing or suspended by a ships crane
  • Accurate sampling of sea surface. Less accurate volume sampler
slide-10
SLIDE 10

On-line filtration from sampler bottle, Ruttner sampler, subsurface

  • Ruttner sampler, clean sampling
  • Easy and low cost
  • Simple to filter directly from bottle
slide-11
SLIDE 11

Sampling intercomparison manta trawl vs in situ pump (w. Örebro U.)

  • 6 replicates, repeated same day, same station, simultaneously
  • Same but different - sampling principles:

– Same mesh size 300µm – Volume: ~120m3 trawl (estimate), ~20m3 pump (measured) – Translates to different measurement uncertainties due to counting statistics – Sea surface microlayer: trawl yes; pump no ?

n=11, σ 30% n=26, σ 20% n=15, σ 26% n=34, σ 17% n=8, σ 35% n=2, σ 71% n=3 n=4, σ 50% n=0 0,00 0,05 0,10 0,15 0,20 0,25 0,30 0,35 0,40 0,45 Plastic particles per m3 Trawl Pumpfiltration

slide-12
SLIDE 12

Different analytical workflow approaches

  • Visual categorization

– Limit in size (> ~100-300µm)* *TGD Marine litter 2013

  • Visual – handpicking – FTIR/RAMAN

– Accurate ID – Time consuming – Size limit of handpicking ~50µm

  • Automated mapping FTIR

– Elaborate pretreatment – Advanced instrumentation FPA-FTIR – Powerful ID – Size limit ~15µm

  • Automated LM-SEM-RAMAN

– Multi-dimensional analysis, Powerful ID – Advanced instrumentation – Size limit ~0.5µm – Automation still under development

slide-13
SLIDE 13

Vibration spectroscopy supported microscopy

  • Infrared absorption spectroscopy (Fourier Transform IR, FTIR)

– Reflectance – Transmission – Attenuated total reflection (ATR) – Simpler, less expensive, ..

  • Raman scattering spectroscopy

– Exitation with laser – Inelastic scattering (loss of energy) – Raman emission (similar to luminescence),

slide-14
SLIDE 14

New case study commissioned by Swedish Marine and Water Management The Uddevalla Byfjorden gradient study

Samples from sediment, surface, deep water, trawl, microplastic filters, nanoplastics

slide-15
SLIDE 15

Case study: Oslofjorden

slide-16
SLIDE 16

Visual classification, #/m3

0,00 5,00 10,00 15,00 20,00

T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 Black filament Blue filament Red filament Green filament Transparent filament White filament Other filament Black NS filament Blue NS filament Red NS filament Transparent NS filament Black fragment Blue fragment Red fragment Green fragment Transparent fragment White fragment Other fragment White foam Other foam Black foil

slide-17
SLIDE 17
slide-18
SLIDE 18
slide-19
SLIDE 19

FTIR identification; >300µm

slide-20
SLIDE 20

Automated mapping FTIR

Vis-Image Chemical Image Microplastics Particles

Acknowl: Gunnar Gerdts, AWI, Germany

slide-21
SLIDE 21

Correlative microscopy

  • Light Microscope => SEM-EDS

– Correlative sample holder – Shuttle ´n Find calibrated transfer

  • SEM-EDS => LM
  • LM => RAMAN
  • Raman inside SEM, (RISE)

– Confocal RAMAN mounted parallel to electron beam in SEM

slide-22
SLIDE 22

Correlativ microscopy in our lab

Scanning Electron microscope Raman microscopes: Insitu and confocal Optical microscope

slide-23
SLIDE 23

Automatiserad analys i SEM-EDS

  • Backscattering detection (heavy element

contrast)

  • Set brightness-contrast threshold
  • Setup entire filter in fields of view
  • Identify particles
  • Perform Elemental analysis on each particle
  • Measure morphology
  • Classify composition and size classes
slide-24
SLIDE 24

Results – antifouling paint particles from ship lane in Baltic Sea

Styr mikroskopet till varje partikel som har hög kopparhalt Avbilda i SEM Avbilda i LM Flytta till LM

slide-25
SLIDE 25

Red copper rich particles – ship lane Bornholm

slide-26
SLIDE 26
slide-27
SLIDE 27
slide-28
SLIDE 28
slide-29
SLIDE 29

Hazard prioritizations…

  • Hazard ranking based on effect studies or

chemical composition?

  • In time we may be more informed to

prioritize – until then we should measure as wide as possible

  • Some bad and ugly could possibly

warrant high prio already now

slide-30
SLIDE 30

pID

slide-31
SLIDE 31
slide-32
SLIDE 32

The needle in the haystack…

  • To find a handfull tin-rich (TBT?) microparticles

in 2L water among millions of natural particles would not be possible without the selective screening methodology and correlative microscopy

  • Now we are extending the technique to also

include RAMAN-µ-spektroskopi

slide-33
SLIDE 33

BASEMAN particles

Reference particles*from JPI-O BASEMAN

LDPE PMMA PC PP PVC PS PA HDPE PP PVC PMMA PA

Optical microscope Scanning Electron microscope Raman microscopes: Insitu and confocal

Correlative microscopy system

* Ref particles have been spiked to sediments, biota tissue and plankton for harmonization ring triel studies

slide-34
SLIDE 34

Acknowledgements

  • Prof. Martin Hassellöv

Therese Karlsson

  • Dr. Karin Mattsson
  • Dr. Andreas Gondikas