Sources, fate & effects of microplastics in the Baltic Should we - - PowerPoint PPT Presentation

Sources, fate & effects of microplastics in the Baltic Should we be concerned?

Dr Peter J Kershaw peter@pjkershaw.com http://www.pjkershaw.com

2 mm Images courtesy of Richard Thompson, University of Plymouth UK

What are microplastics? < 5mm

(Graphic from GESAMP 2015, inspired by Won Joon Shim, KIOST)

No agreed ‘official’ definition

Example: expanded polystyrene

< 100 nm nano-particles

a) images courtesy of: a) Joel Baker; b) Hideshige Takada; c) A. Bakir & R. Thompson)

Examples of ‘primary’ microplastics – made for a purpose

Toothpaste extract Plastic resin pellets – used by plastics industry Facial scrub extract

(GESAMP in press)

a) images courtesy of: a) Joel Baker; b) Hideshige Takada; c) A. Bakir & R. Thompson)

Examples of ‘primary’ microplastics – made for a purpose

Toothpaste extract Plastic resin pellets – used by plastics industry Facial scrub extract

(GESAMP in press)

Improved protocols to reduce spillage

Prevention is the key

The Swedish Chemicals Agency (SCA) proposes that:

1. the Government prohibit the sale on the Swedish market of rinse off cosmetic products that contain plastic microbeads. (Apply from 1th

• f January 2018).

2. Sweden continue to seek to achieve an EU-wide regulation. If and when this is in place, a Swedish ban should be adapted to the EU- wide one.

• Proposal is legal under EU law (REACH, Cosmetics regulations)
• Complement any voluntary agreements
• Produce a ‘level playing field’

3/9/2016 HELCOM ML Stakeholder Conference Johanna Eriksson 5

‘Secondary’ microplastics: wear/weathering/fragmentation of larger plastic

• bjects

Examples:

• Fragmentation of macro-debris by UV
• Fibres from clothing
• Wear & tear of fishing gear
• Dust from car tyres
• Damage to aquaculture structures
• Paint flakes

Large-scale shellfish aquaculture, South Korea

More complex waste management issue

NOAA Marine Debris Program EPS debris, S Korea, OSEAN

Land-based sources of microplastics Improved collection & treatment of wastewater & solid waste

Sea-based sources of microplastics Improved design & modified practices (ship loading, fishing gear design ………)

How bad is the Baltic?

Modelling the relative abundance of floating microplastics

Sources estimated using three proxies:

• Coastal population density
• Shipping density
• Proportion of urbanised catchment

(more rapid run-off)

• 93,000

(taken from the Transboundary Waters Assessment Programme, http://geftwap.org )

Surface waters (model layer 1) Bottom waters (model layer 12)

Modelling the distribution of different types of plastic micro-particles (330 microns), introduced by rivers

Polyethylene (PE) Density = 0.91 Polystyrene (PS) Density = 1.05 Polyethylene terephthalate (PET) Density = 1.40 Seawater average density = 1.025

PE floats PS intermediate PET sinks

(Van der Meulen et al. 2015,EU MICRO project)

Secondary microplastics - fragmentation rate poorly quantified

• varies with environmental compartment

(GESAMP 2015)

Impacts: Ingestion by birds, fish, invertebrates ………

Stomach contents of an individual northern fulmar (F.glacialis) from Svalbard in the Arctic. (images courtesy of Jan van Franeker and Alice Trevail) Scale bar indicates 10 mm (Trevail et al. 2015)

Impacts: Microplastics as a source of contaminants?

PBDEs (polybrominated diphenyl ethers) - used as a flame retardant on textiles & as an additive in some plastic products, and are endocrine disrupters

Kosuke Tanaka, Tokyo Univ. Agric. & Technol. Tanaka et al., 2013, Mar. Poll. Bull., 69, 219-222

Gut transfer of PBDE flame retardants from plastic to fatty tissue

Short-tailed shearwaters, northern North Pacific Ocean

• Plastics absorb and desorb contaminants – e.g. PCBs, DDT & other POPs
• Some plastics release chemical additives – e.g. PBDEs

Microplastics & seafood safety

• Actual risk
• Perceived risk – consumer choice

Microplastics found in a wide variety of fish and shellfish ‘…….. the uptake of plastic-associated chemicals in humans due to inadvertent ingestion of microplastics in seafood appears likely to be no more significant than other human exposure pathways of these chemicals. However significant knowledge gaps and uncertainties remain, particularly for nano-sized material, and this may justify a more precautionary approach.’

UNEP (in press)

Rafting – potential social& economic impacts?

Microbial biofilm on microplastic from North Atlantic: includes pathogenic Vibrio bacteria

(image courtesy of Erik Zettler/SEA)

Medusa of the giant jellyfish Nemophiliema nomurae Planulae favour plastic over natural substrates: Yellow Sea, Sea of Japan (images courtesy of Shin-ichi Uye, Univ. Hiroshima) planula polyps

Microplastics as linked to jellyfish

• utbreaks

Microplastics - key message: we should be concerned

• Many different sources and entry points (therefore multiple

intervention points and measures needed)

• Distributed widely in the ocean (dependent on composition)
• Widespread uptake by biota
• Absorption and release of harmful chemicals
• Present in seafood
• Potential for consumer concern
• Potential for rafting of organisms
• Cannot be removed from the ocean – prevention is the key