This document provides an overview of environmental risk assessment (ERA) of chemical pollutants. ERA determines or predicts the negative impact of chemicals on the aquatic environment. It involves estimating the predicted environmental concentration (PEC) of chemicals and comparing it to the predicted no effect concentration (PNEC) to calculate the risk quotient. PEC is estimated through exposure assessment, while PNEC is derived through effects assessment using toxicity data from multiple species. The European Union System for Evaluation of Substances (EUSES) is a tool that can be used to conduct a comprehensive ERA.

1. Environmental Risk Assessment of chemical pollutants – VMK 2010
Environmental
Risk Assessment of
Chemical
pollutants

2. Environmental Risk Assessment of chemical pollutants – VMK 2010
What is ERA ?
Determine or Predict the negative impact of
chemical pollutants on the environment (aquatic)

3. Environmental Risk Assessment of chemical pollutants – VMK 2010
Risk Quotient =
PEC / PNEC
Principle

4. Environmental Risk Assessment of chemical pollutants – VMK 2010
PNEC
• Based on multi-species and
• local species – site-specific ERA
• Literature based toxicity data or new toxicity experiments
PEC
• RA for each environmental compartment i.e. sediment, surface water, groundwater,
etc.
• RA at different spatial scales

5. Which chemicals (substances)
to Assess?

6. Environmental Risk Assessment of chemical pollutants – VMK 2010
Priority Substances
> 100.000 EINECS substances
> 2000 HPVCs
140
Priority
Substances

7. Environmental Risk Assessment of chemical pollutants – VMK 2010
Priority lists:
factors to taken account
• the effects of the substance to man or the
environment;
• the exposure of man or the environment to the
substance;
• the lack of data on the effects of the substance on man
and the environment;
• work already carried out in other fora;

8. Environmental Risk Assessment of chemical pollutants – VMK 2010
Substance may obtain high scores if, for example
– it is produced in large volumes
– is used in a dispersive manner
– persists in the environment
– is highly toxic to humans, animals or plants
– has long term/chronic effects
– is carcinogenic, mutagenic or toxic to reproduction
– little is known about its properties, use or effects
Example: EU criteria for classification of Priority substances

9. Environmental Risk Assessment of chemical pollutants – VMK 2010
STP
Air
Use
2. Effects Assessment
Aquatic + Terrestrial
Environment
Production
1. Exposure Assessment
determine how much chemical will reach the
environment
T
ra
n
s
p
o
rt
Determine the toxicity of the
chemical on biota
(algae, invertebrates, fish)
Put in same units
i.e. µg/L
Overview of ERA of chemicals
3. Risk Characterisation
Exposure
effects

10. Environmental Risk Assessment of chemical pollutants – VMK 2010
1. Hazard Identification
- new substances, ‘potential hazard’ based on scientific judgement
- existing substances – toxicity data
2. Effect Assessment
Calculate the Predicted No Effect Concentration
(PNEC)
3. Exposure Assessment
Calculate the Predicted Environmental Concentration
(PEC)
4. Risk Characterization
Calculate the Risk Quotient = PEC / PNEC

11. Environmental Risk Assessment of chemical pollutants – VMK 2010
Environmental Risk Assessment:
The general framework
PEC/PNEC
Risk characterization
Chemical with
potential hazard
Single species
toxicity data
Extrapolation
PNEC
Effects assessment
Emissions
Distribution
PEC
target environment
Exposure assessment
EUSE
S

12. Environmental Risk Assessment of chemical pollutants – VMK 2010
• Content of substance in productsContent of substance in products
• Service life of substance / productsService life of substance / products
• Disposal / re-cycleDisposal / re-cycle
• Production volumesProduction volumes
• Distribution of substanceDistribution of substance
• Function (use) of substanceFunction (use) of substance
1. Exposure Assessment1. Exposure Assessment
Objective : To Predict the Environmental Concentration (PEC)
of the active substance
Parameters to take into account
• Characteristic of the recieving environmentCharacteristic of the recieving environment
Life cycle

13. Environmental Risk Assessment of chemical pollutants – VMK 2010
Life cycle stepsLife cycle steps PRODUCTION
FORMULATION
SERVICE LIFE
PRIVATE USE
INDUSTRIAL USE
In product In product Processing
aid
-
Processing
aid
WASTE DISPOSAL
- Incineration
- Landfilling
- Recovery

14. Environmental Risk Assessment of chemical pollutants – VMK 2010
PRODUCTION
FORMULATION
SERVICE LIFE
PRIVATE USE INDUSTRIAL USE
WASTE DISPOSAL
Exposure Assessment at different spatial scales
i.e. local, regional, continental
PEC Local
PEC Regional
PEC Continental

15. Environmental Risk Assessment of chemical pollutants – VMK 2010
Target environment
__________________________________________
Surface water aquatic organisms
Sediment sediment organisms
Soil terrestrial organisms
________________________________________
2. Effects Assessment
Objective: to Predict No Effect Concentration (PNEC) i.e. the
threshood at which the substance posses no significant adverse
effects

16. Environmental Risk Assessment of chemical pollutants – VMK 2010
Effects assessment
• based on laboratory tests using single species and single chemicals
• different trophic levels
• obtain toxicity values i.e. short-term and /or long-term toxicity data
• calculate PNEC from the end-points (i.e. LC50, EC50) values
algae
invertebrate
fish
Aquatic ecosystems

17. Environmental Risk Assessment of chemical pollutants – VMK 2010
3. Risk
Characterization
PEC
PNEC
Risk Quotient =
< 1 no risk to the environment
> 1 there is a risk, measures should be taken
to reduce the risk
Risk Management - risk reduction steps
- monitoring
- political, social, economic decissions

18. Environmental Risk Assessment of chemical pollutants – VMK 2010
1. Exposure and Fate Assessment Screening Tool (E-FAST V2.0)
• It basically a screening tool intended for rapid assessment
• it estimates concentrations of chemicals released to air, surface
water, landfills, and from consumer products.
• It support both new and existing chemical programs.
• E-FAST tends to and is designed to reasonably overestimate
exposures.

19. Environmental Risk Assessment of chemical pollutants – VMK 2010
2. ReachScan
• Essentially, the purpose of ReachScan is to estimate concentrations of
the chemical in surface water downstream from an industrial source to a
drinking water facility.
• It provides data about human habitation in the area of interest.
• It is basically concerned with human risk assessment
• but also estimates a level of the chemical that may adversely affect
aquatic organisms.

20. Environmental Risk Assessment of chemical pollutants – VMK 2010
3. Others
• AQUATOX is a freshwater ecosystem simulation model. It predicts the
fate of various pollutants, and their effects on the ecosystem, including fish,
invertebrates, and aquatic plants.
•Assessment Tools for the Evaluation of Risk (ASTER) – Mainly used
by regulators in performing ecological risk assessments by providing high
quality data for discrete chemicals.

21. Environmental Risk Assessment of chemical pollutants – VMK 2010
European countries
European Union System for
Evaluation of Substances
(USES)

22. Environmental Risk Assessment of chemical pollutants – VMK 2010
European Union System for the
Evaluation of Substances
EUSES

23. Environmental Risk Assessment of chemical pollutants – VMK 2010
Why EUSES ???
- Its the most recent and comprehensive (many
parameters considered)
- More realistic estiamates of processes such as
degradation rates, geochemical processes
- Easy to adapt to other parts of the world
- Can be used for preliminarly and final
assessment

24. Environmental Risk Assessment of chemical pollutants – VMK 2010
EUSES: latest version (2.0.1)
• More complete life cycle assessment
• Release estimation
– emissions from long-life articles
– emissions from waste disposal including recovery
• Unintentional uses: calculation of background
concentrations
• Biocide assessment
(assessment of biocides when used for non –
agricultural purposes)

25. Environmental Risk Assessment of chemical pollutants – VMK 2010
What we will do with EUSES
• Perform ERA for n-pentane.
• Perform parameter sensitivity analysis i.e. identifying those
factors with the most influence on ERA of individual chemicals
(n-pentane as an example)
• Adapting EUSES for other geographical regions /countries
(editing default parameters)
• ERA for Biocide (Assessment of non -agricultural use of biocides)
• Several assingments on ERA using EUSES

26. Environmental Risk Assessment of chemical pollutants – VMK 2010
Useful references
Books /Documents
Risk Assessment of Chemicals: An Introduction.
C.J. van Leeuwen and J.L.M. Hermens (eds). 1996 Kluwer
Academic Publishers, ISBN 0-7923-3740-9
Technical Guidance Document (TGD) in support of EUSES
(European Chemical Bureau)
Internet resources
http://ecb.jrc.it/ (European Chemical Bureau, responsible for
EUSES)
www.ecotox.org (searchable toxicity database from the EPA –
USA).