From the lab to the fieldGetting the most from your studies
Dr Peter Aikens
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Challenges and solutions
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E-fate lab study design
Options around higher tier work
Case studies
Aquatic
 Terrestrial
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Conclusions
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E-Fate: Lab study design

Get the basics right
Position of label & number of labelled forms
 Application rate & test system:
 Sampling schedule
 Mass balance: volatiles & bound residue
 Effective chromatography
 Metabolite ID, where necessary
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Achieve this before higher tier work
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Water/sediment studies
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6 samples over 100 days?
(including T=0)
Data from preliminary studies vital in certain
cases
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Introduction of higher tiers
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Standard OECD308, DT50 = 48 days
Irradiated lab microcosm
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180 litre glass aquarium containing sediment (depth 5 cm)
& water (depth approximately 35 cm)
18ºC, illuminated with light simulating natural daylight in a
14:10 hour light:dark cycle
Samples of water and sediment were monitored over an 11
week period
DT50 = 50 days
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Field facility
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60 fibre-glass shallow water microcosms
[1.8 x 0.8 x 0.6 m] 
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water depth 30 cm, capacity 500 L(EU “ditch”)
Central large reservoir [ca. 180,000 L
capacity] – source of water, sediment, plants
and invertebrates
Field laboratory for sample processing and
data collection next to the field facility
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ERC field facilities
Eye Research Centre – New pond layout January 2010
60
55
59
54
49
58
53
57
56
50
45
40
35
30
25
44
39
34
29
1
24
48
43
38
0
33
28
23
52
47
42
37
9
32
27
22
51
46
41
36
31
26
21
Centre Pond
15 m
mmm
12 m
mmm
61 m
WRJ 1/12/09
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20
15
10
5
19
14
9
4
18
13
8
3
17
12
7
2
16
11
6
1
Layout dimensions in this diagram are not to scale
27 m
Establishment
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We established realistic microcosms to
represent the worst case standard
‘model’ i.e. - 30 cm deep edge-of-field
ditch or shallow pond.
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Microcosms 2m x 0.8m x 30cm water
Sediment , ca. 4 % organic carbon
Macrophytes
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Sampling
Water
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Macrophytes
Sediment
Field degradation
Water
Macrophytes
Sediment
Study type
DT50
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Lab sedimentwater
Lab microcosm
Field microcosm
48 days
50 days
16 days
Aquatic case study
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Rice herbicide, case study
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Pre & early post emergence herbicide
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Lab studies
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Rice paddies EU
Paddy soil OECD307, OECD308
Field studies
Spain & Italy (2 treated rep/site plus control each
90m2)
 Fields drained, application, flooded after 3 days

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Degradation profile
Study type
Soil description
DT50 (days)
Water
Soil
Total system
(water + soil)
Lab. Paddy soil
Clay
14
106
108
Lab. Paddy soil
Sand
20
567
585
Clay loam
4.1
119
99
Sandy loam
4.8
125
91
Clay
4
116
nc
Sandy clay loam
nc
1
nc
Lab.
Water/sediment
Lab.
Water/sediment
Field, Paddy,
Spain
Field, Paddy, Italy
nc, not calculable
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Concerns
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TER triggers: acute (100) & chronic (10)
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Birds & mammals risk assessment
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Rice paddy site
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Paddy field : soil concentration
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Paddy water, PEC modelling
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Invertebrate sampling
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Total Counts, nekton & benthic
invertebrates: Spain
Family
Control
Treated
Chironomidae
12
17
Culicidae
0
1
Dipterans
0
2
Collembola
Isotomidae
2
0
Ephemeroptera
(Mayflies)
Baetidae
0
1
Odonata
(Damselfies &
Dragonflies)
Coenagriidae
45
67
Corduliidae
0
1
Libellulidae
0
1
Hemiptera
Corixidae
0
1
Lepidoptera
Pyralidae
0
1
Coleoptera
(Beetles)
Dytiscidae
623
647
Hydrophilidae
53
30
Agelenidae
1
0
Hydracarina
0
1
Sediment
dwelling
organisms
Entirely aquatic life
history
Insects with aquatic larval/pupal
stages
ORDER/CLASS
Diptera
(Trueflies)
Areneae
(Water spiders)
Hydracarina
(Water mites)
Pulmonata (Snails)
Oligochaeta
(Worms)
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Physidae
1861
1069
Planorbidae
18
442
Lumbriculidae
112
71
Tubificidae
227
769
Tubificidae (Branchiura)
105
31
Naididae
2
23
Ecological function
Total number of organisms
Number of taxa
Shannon-Weiner Diversity index
Control
Treated
3061
3175
12
18
1.253
1.650
No effect on ecological function based on
invertebrate diversity & abundance
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Residues: higher trophic levels
No residues detected in higher trophic levels
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Conclusions- rice herbicide
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Supported reduction of TER triggers to 10 (acute)
and 1 (chronic)
Demonstrated no risk to birds and mammals
Validated higher tier PEC modelling
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Terrestrial case study
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Field soil dissipation- soil fumigant
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Field soil dissipation study
PLUS
Concern over residues in non-target species
Non-target organisms may be eaten by mammals
and avian species
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Non-target organisms tested
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Insect species
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carabid beetles, adult crickets, aphids, meal
worms and blow fly pupae
Earthworms
Barley and pea seedling plants and seeds
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Test substance application
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Location of samples
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Location 1: underneath the virtually
impermeable film (VIF)
Location 2: on top of the VIF
Location 3: immediately adjacent to treated areas
(between the film covered plots) and at a distance
of 0.5 m from the VIF
Location 4: 1 m from the border of the VIF in
the outside rows.
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Test substance application
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Test site, post application
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Insect residues (under film)
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Seed residues (under film)
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Residue concentrations, above film
Location
2
(On top of the
VIF)
1 DAT
0.7
3 DAT
0.43
7 DAT
<LOQ
3
(0.5 m from
the VIF)
<LOQ
0.47
ND
4
(1m from the
VIF)
<LOQ
1.23
ND
Results expressed as mg/kg
ND – not detected (less than the limit of detection of 0.01 mg/kg)
<LOQ – less than the limit of quantitation of 0.05 mg/kg
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Blowfly pupae
Carabid Beetles
Meal worms
Earthworms
Aphids
Crickets on plants
Crickets (in bags)
Pea plants
Barley plants
Pea seeds
Barley seed
Results
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Dissipation profile in soil confirmed
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Residues from below film samples demonstrated
exposure and rapid dissipation
Above film: very low residues, short duration
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Experimental data confirmed no risk to birds and
mammals from exposure to non-target species
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Conclusions
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Get the basics right
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Lab studies & metabolite identification
Inter-disciplinary review
Focus on regulatory questions
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Think out-of-the-box
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Don’t generate unnecessary data
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Planning ahead saves time and money
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Acknowledgements
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E Fate team
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Aquatic & Terrestrial Ecotoxicology team
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Javier Bartolome
Environmental Analysis team
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Jane Gray & Carole Jenkins
Field Trials team
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Sara Penketh
Mick Todd & Steve Brewin
LSR Associates team

David Shaw & Andrew Lattimore
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Thank you for listening
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