Occurrence and potential effects of microplastics in the Belgian coastal area

By:ir. S. De Meester

M. Claessens

Facts

• Growing plastic production:1950: 1.5 million tons per year2006: 245 million tons per year

• The largest part is still being dumped• Worldwide problem: the oceans are connected

Facts

• Growing plastic production:1950: 1.5 million tons2006: 245 million tons

• The largest part is still being dumped• Worldwide problem: the oceans are connected• Of all garbage 60-80% is plastic (macroplastics)

UV + mechanical forces

0 1

Microplastic

Microplastics

• Thompson et al. 2004:“Lost at sea, where is all the plastic”

• Detection of microplastics in sediment and water

• In all following research microplastics were found, but there is no agreement on concentrations

Overview of this research

• Method• Occurrence in the Belgian Coastal area?• Historical trend?• Origin?• Microplastics vs macroplastics?• Potential effects?• Conclusion

Method

•

Koksijde-Bad

•

Groenendijk

•

Nieuwpoort

•

Sandbank

•

Zeebrugge

•

Oostende

Method

Microplastics

Sediment

Saline solution

Taking samples in the Belgian coastal area

Filtration of top layer

Identification with IRStirring sediment in

a saline solution

• Searching for an appropriate method was difficult• Method of Thompson modified (based on density)

Method

0 10 1

0 0.5

0 1

Scale: mm

0 0.5

Fibers

Granules

Plastic films PS spheres

Occurrence (Belgian coastal area)

Fibers Granular Plastic films0

20

40

60

80

100

120

109

8 9

81

4 4

46

61

58

4 0

94

30

2

High-tide markIntertidalSubtidalSandbankBelgian Continental

Num

ber

of p

arti

cles

.kg-

1dry

sed

imen

t

Occurrence (Belgian coastal area)

Fibers Granular Plastic films0

100

200

300

400

500

600

700

800

900

1000

82

257

418

61

136

196

35

189

4044

113

13

71

947

94

High-tide markIntertidalSubtidalSandbankBelgian Continental

Conc

entr

ation

mic

ropl

astic

s (µ

g/kg

)

Occurrence (Oostende)

Fibers Granular Polystyrene spherules Plastic films0

20

40

60

80

100

120

77

61

46

2

94

100

77

2

73

24 24

0

46

35

26

2

OO1OO2OO3OO4

Num

ber o

f par

ticle

s.kg

-1dr

y se

dim

ent

Historical trend?

Short-term (Koksijde-Bad)

Fibers Granular Plastic films0

10

20

30

40

50

60

70

80

90

10085

6 5

76

71

79

62

91

4 3

KBWL-Top layerKBWL-2nd layerKBWL-3th layerKBWL-Deepest layer

Num

ber o

f par

ticle

s.kg

-1dr

y se

dim

ent

Long-term (Groenendijk)

Fibers Granular Plastic films0

102030405060708090

100110120130140 132

10 14

85

8 8

74

8 5

48

5 1

GHWL-Top layerGHWL-2nd layerGHWL-3th layerGHWL-Deepest layer

Nu

mb

er o

f p

arti

cles

.kg-

1dry

sed

imen

t

OriginFibers: Fishery,…

Granular: shipping, sewers, tourists,…Plastic films: tourism, shipping,…

PS spherules: scrubbers in (hand) cleansers: used in harbours. PS sinks: up to 100 spherules/m³

Microplastics vs macroplastics

• Difficult: no unity in research (per m²,kg,…?)Macroplastics: ± 52 – 1179 g/100m²Microplastics: ± 5 – 11 g/100m²

± 1 – 20% of all plastic is microplastics (weight)

More unity & further research needed

Potential effectsPlastic

Pollutant

Potential effectsPlastic

Pollutant

Potential effectsWorst case calculation through equilibrium Microplastics are indeed able to spread the pollution and transfer it

through pore water to organisms Arenicola marina in an otherwise clean environment with contaminated

microplastics can take up 0.0077ng phenanthrene and 0.0706ng PCB per worm

Physical effects?Ingestion?Desorption?…?

Further research needed (experiments)

Conclusion

• Microplastics were found in all samples• The problem seems to be growing• A lot of further research needed:– Effects: physical & chemical experiments– Method needs to be optimized (density + particles

< 30nm)– …