Ecotoxicology and environmental/ecological risk assessment...
Transcript of Ecotoxicology and environmental/ecological risk assessment...
Ecotoxicology and
environmental/ecological
risk assessment: quo vadis? a personal SWOT analysis
Colin Janssen
Laboratory of Environmental Toxicology and Aquatic Ecology
Ghent University, Belgium
CEFIC-LRI workshop Brussels, 18-11-2010
Opening statements
ERA is not … just an extension of HRA using other test species! 2000000 potential targets; different protection goals
A lot of data… little knowledge
Technology-driven research without clear hypotheses is not helpful
Unbalanced research efforts in exposure and effects assessment
LRI: short-term “fire fighting” vs. long-term vision?
Ecotoxicology: what?
Aim: to maintain the natural structure and function of ecosystems
Definitions: ‘ecotoxicology is concerned with the toxic effects of chemical and physical agents on living organisms, especially on populations and communities within defined ecosystems; it includes the transfer pathways and their interactions with the environment’ (Rand, 1995)
Keep the purpose in mind: different approaches may have different goals (e.g. scientific, technological or practical/regulatory)
Strengths:Clearly defined goals
Weaknesses:
Tools and measurements are
not compatible with goals
CEFIC-LRI workshop Brussels, 18-11-2010
Regulatory ecotoxicology:
confused on aims...and use of data
Local GlobalValue
Tim
e t
o b
en
ifit
Other Sciences
Other Technologies
Other Laws and Regulations
Other Social Needs
CEFIC-LRI workshop Brussels, 18-11-2010
Local GlobalValue
Tim
e t
o b
en
ifit
Technology
Science
Practice
Ecotoxicology needs increased efforts
from all sides…
CEFIC-LRI workshop Brussels, 18-11-2010
The Threats…
Data explosion (data of low relevance)
Promise of something better… without coordinated action
Measuring wrong assessment endpoints
Over-estimation of relative importance of chemical stress vs. other threats (e.g. global warming)?
Emerging substances and technologies
Chemical mixtures
E2
NP
BP
A
EE
2
CEFIC-LRI workshop Brussels, 18-11-2010
Ecotoxicology: …mind the gap
Ecological relevance
7
Human Health
Eco-Toxicology
CEFIC-LRI workshop Brussels, 18-11-2010
Ecotoxicology:
…we are going in the wrong direction!
Ecological relevance
1/P
recis
ion
Strengths:Promise of in vitro/in silico data
Mechanistic understanding
Weaknesses:
Technology driven research
Not (yet) compatible with ERA goals
CEFIC-LRI workshop Brussels, 18-11-2010
EU risk assessment:
mainly prescription scienceExposure
AtmosphericDeposition
Erosion& Runoff
Untreated discharges
Predicted ExposureConcentration (PEC)
Effects
Laboratory studiesEcotoxicity tests
Predicted No Effect Concentration (PNEC)
WWTP
CEFIC-LRI workshop Brussels, 18-11-2010
1010
Mind the gap
According to European legislation:
Chemicals shall have no unacceptable effects on the environment;
Aim is to prevent adverse effects on human health and the environment;
...etc., etc.,…
What we measure in
practice:
Acute LC50s
Chronic ECx
More of the same (SSDs)
Mesocosm/semi-field effects
We need to make the protection goals operational!
CEFIC-LRI workshop Brussels, 18-11-2010
More data… less uncertainty?
Strengths:More relevant data is good
Weaknesses:
Uncertainty not accounted for in most ERAs
PP creeps in the science arena
CEFIC-LRI workshop Brussels, 18-11-2010
Effects assessment:
disconnect reality and goals
50
100
LC50 [concentration] in mg/L or % effluent
Threshold:
No Observed Effect Concentration (NOEC)
Strengths:
Tests can be adapted to measure/calculate
relevant endpoints for ERA
Weaknesses:
Simplicity
We’re not doing this….
CEFIC-LRI workshop Brussels, 18-11-2010
Ecotoxicity test data
PNEC
0
0,2
0,4
0,6
0,8
1
1 10 100 1000
NOEC values (µg Cu/l)
cum
ula
tive d
istr
ibution
invertebrates
fish
algae + higher plant
Effects assessment: PNEC extrapolation
No scientific evidence…
Strengths:…
Weaknesses:
Little scientific evidence for factors used
Statistical models better but
lack further validation
CEFIC-LRI workshop Brussels, 18-11-2010
Effects assessment
Too much bad data…
0
20
40
60
80
algae invert (F) fish (F) invert (M) fish (M)
Literature search: 156 data points
Application of QC/QA and acceptance criteria
34 data points (22 %) useful in risk assessment
# t
ox
icit
y t
est
resu
lts
Quality and relevance of the (scientific) data used
for RA, in most cases, POOR !
CEFIC-LRI workshop Brussels, 18-11-2010
Release estimation
volumes
+ emission scenarios (A and B tables; Appendix I)
Characterisation of environmental compartment
generic (default)
actual
Partitioning between compartments
Biotic and abiotic degradation rates
Elimination processes prior to release to environment
Exposure assessment:
uncertain models…validation?
Strengths:Uniform system for generic environment
Weaknesses:
Little validation
Too many defaults and assumptions based
on limited scientific evidence
No uncertainty analysis
Risk characterisation:
where’s the probability of risk?
Hazard identification
Base set of data
Exposure assessment
Effects assessment
PEC PNEC
Risk characterisation
PEC/PNEC
> 1 < 1
Strengths:Clear Yes or No
Weaknesses:
Based on … all of the above
No probability? Severity? Uncertainty?
CEFIC-LRI workshop Brussels, 18-11-2010
Data: Dr. F. Verdonck
Uncertainty band
or confidence
ExposureEffects
SSDECD
% risk Tilapia
Daphnia
Risk characterisation:
better ways… but…
CEFIC-LRI workshop Brussels, 18-11-2010
PNEC
Risk charactersation:
ecosystem structure vs. functionEffects on density ≠ effects on related functions
CEFIC-LRI workshop Brussels, 18-11-2010
10 20 30 40 50
mg
C l
1 d
1
-10
12
3
control
time (days)10 20 30 40 50
mg
C l
1 d
1
-10
12
3
*** *
low treatment
time (days)
* *10 20 30 40 50
mg
C l
1 d
1
-10
12
3
* ** * * * *
medium treatment
time (days)
* *10 20 30 40 50
mg
C l
1 d
1
-10
12
3
* * * ** * *
high treatment
time (days)
* * * * *
ecosystem functions:
NPP, modelled
NPP, measured
NZP, measured
NBP, modelled
10 20 30 40 50
mg
C l
1
0.0
01
0.1
00
10
.00
00
.00
10
.10
01
0.0
00
control
time (days)10 20 30 40 50
* * ***
***
mg
C l
1
0.0
01
0.1
00
10
.00
0
*0
.00
10
.10
01
0.0
00
low treatment
time (days)10 20 30 40 50
* * * **
* * **mg
C l
1
0.0
01
0.1
00
10
.00
0
**
0.0
01
0.1
00
10
.00
0
medium treatment
time (days)10 20 30 40 50
* * * *
mg
C l
1
0.0
01
0.1
00
10
.00
0
*
0.0
01
0.1
00
10
.00
0
high treatment
time (days)
species densities:
phyzoo
mic
10 20 30 40 50
mg
C l
1 d
1
-10
12
3
control
time (days)10 20 30 40 50
mg
C l
1 d
1
-10
12
3
*** *
low treatment
time (days)
* *10 20 30 40 50
mg
C l
1 d
1
-10
12
3
* ** * * * *
medium treatment
time (days)
* *10 20 30 40 50
mg
C l
1 d
1
-10
12
3
* * * ** * *
high treatment
time (days)
* * * * *
ecosystem functions:
NPP, modelled
NPP, measured
NZP, measured
NBP, modelled
10 20 30 40 50
mg
C l
1
0.0
01
0.1
00
10
.00
00
.00
10
.10
01
0.0
00
control
time (days)10 20 30 40 50
* * ***
***
mg
C l
1
0.0
01
0.1
00
10
.00
0
*
0.0
01
0.1
00
10
.00
0
low treatment
time (days)10 20 30 40 50
* * * **
* * **mg
C l
1
0.0
01
0.1
00
10
.00
0
**
0.0
01
0.1
00
10
.00
0
medium treatment
time (days)10 20 30 40 50
* * * *m
g C
l1
0.0
01
0.1
00
10
.00
0
*
0.0
01
0.1
00
10
.00
0
high treatment
time (days)
species densities:
phyzoo
mic
No effects on
primary
production
100 fold
increases of
phytoplankton
density
Risk assessment vs. risk management:
… different languages.. no translation
CEFIC-LRI workshop Brussels, 18-11-2010
Paradigm shift in risk assessment and
management: towards clear endpoints and criteria...
CEFIC-LRI workshop Brussels, 18-11-201020
Public values
Ecosystem services
Driver & itsattributes
Exposure tochemicals
Effect ondriver
Decline inservice
Can be valued
Weigh benefit of chemicaluse with cost of impaired
services
The Opportunities:
Paradigm shift needs
Exposure:• validated models• more measurements
Ecosystem:• bioavailability• non-chemical stress
Effects:• eco-endpoints• ecosystem modelling
• ecosystem level• graded results• + uncertainty!
• clear criteria• common currency• communication
CEFIC-LRI workshop Brussels, 18-11-2010
The Opportunities…
In theory… we have the right paradigm… but, we need a shift
Look up, don‟t look down too much…
LRI: connect academic science with real (long-term) needs Plant the seeds now… be prepared to
harvest later…
LRI: more Long-term vision, less „fire fighting‟
CEFIC-LRI workshop Brussels, 18-11-2010
Change: Yes… we can!(Anonymous (?), 2008)
CEFIC-LRI workshop Brussels, 18-11-2010
term