Transcript Development of emission scenarios for biocides in the

OECD Environmental Emission
Scenarios:
Wood Preservatives (PT 8)
Hannu Braunschweiler
Finnish Environment Institute (SYKE)
EU course “Exposure scenarios in Risk Assessment
of Wood Preservatives and Rodenticides”
9-10 October 2003, ECB, Ispra
OECD Emission Scenario
Document for Wood Preservatives
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Developed in the OECD Expert Group on the basis of a workshop,
published by OECD in March 2003
•
•
Some of the scenarios have been tested in the EUBEES-2 project,
primarily with regard to usability
Adopted at the 14th EU Competent Authority meeting June 2003:
•
1.5.2020

OECD Series on Emission Scenario Documents No. 2
Parts 1-4
“CAs recommend its use with the note that the ESD is a living
document.”
• “The ESD can be revised in the light of new knowledge, experience
gained in its application, and data from real measurements made by
industry.”
The ESD is available also through http://ecb.jrc.it/biocides/
Life-cycle of a wood preservative
Production of a.s.
Formulation of B.P.
*) Life-cycle stage
covered in the ESD
Private/professional use “in-situ”*
Industrial preventive use*
Product application (processing)*
Product application (processing)*
Service life of treated wood (“wood-in-service”)*
1.5.2020
Waste treatment(*)
Recovery
Potential environmental exposure from
wood preservative applications
Emission scenario
Soil
Ground
water
Waste
water
Surface
water
Preventive applications (before wood-in-service, and professional and amateurs also "in-situ")
Automated spraying or dipping, industrial sawmill
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Industrial vacuum pressure
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Double vacuum, industrial joinery
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Manual or mechanised dipping (large scale joinery)
Dipping (small scale joinery)
Spraying or injection (indoors)
Brushing (indoors), amateurs or professionals
Brushing (outdoors), amateurs or professionals
Injection or wrapping (outdoors), professional
Termites prevention of foundation
Curative applications (remedial, "in-situ")
Spraying or injection (indoors)
Brushing (indoors), amateurs or professionals
Brushing (outdoors), amateurs or professionals
Fumigation, professional
Injection or wrapping (outdoors), professional
Termites prevention of foundation
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Air
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Detailed scenarios in the ESD
 Focus of the emission scenarios
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1) industrial preventive treatments
2) treated wood in service
3) in situ treatments (curative and preventive)
Two options for calculation of Clocal
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•
1.5.2020
Estimation of local emissions to primary receiving
environmental compartments and local environmental
concentrations within them from:
without removal processes of the substance (Ch. 4-6)
with removal processes in the receiving compartment
(e.g. due to degradation, volatilisation, leaching to
groundwater ) -> modified formulas in Chapter 7
Time scales of the scenarios

Local emissions and concentrations from
treated wood
•
Storage of industrially treated wood:
a) initial assessment = 30 days (TIME1)
b) longer assessment period, > 30 days (TIME2)
•
Treated wood-in-service:
1.5.2020
a) initial concentration; immediately after the last
application (e.g. at the end of the application day)
b) 30 days; covers the initial leaching
c) during the rest of the service life (> 30 days). Depending
on the characteristics of the active ingredients and the
service life of treated commodities, time periods of
several years of service life can be used
Structure of the ESD
Chapter 2
Overview of the treatment types and processes, different
wood preservatives and uses of treated wood
Chapter 3
Background and approaches behind the scenarios and
calculations
Chapter 4
Three scenarios for emissions from industrial preventive
applications
Chapter 5
Scenarios for emissions during the service life of industrially
treated wood, summary of leaching test requirements
Chapter 6
Scenarios for emissions from preventive and curative in-situ
treatments, by professionals and/or amateurs, cover
treatments and wood-in-service
Chapter 7
Approach for emissions from treated wood as a function of
time and taking into account removal processes of
substance (e.g. leaching and degradation)
Appendixes
General requirements for leaching tests, full description of
wood-in-service scenarios, guidance for calculation of
fluxes, description of some ground water calculation models,
examples of emission calculations, glossary etc.
Industrial preventive treatment
 3 scenarios
• Automated spraying processes
• Dipping/immersion processes
• Pressure processes
 For all 3 scenarios, emissions take place during
1.5.2020
• Treatment process
• Post-treatment conditioning
• Storage of treated wood prior to shipment
Preventive industrial processes:
compartments of concern
Process(*
Application/
Scenario
Storage of treated wood(**
Air
Waste
water
Surface
water
Soil
Automated
spraying
+
+
(+)
+
+
+
Immersion/
dipping
+
+
(+)
+(1
+(1
+(1
Pressure
processes
+
+
(+)
+(1
+(1
+(1
(*No emissions to soil
(**No emissions to air and wastewater
(1
1.5.2020
Ground Surface
water
water
Not relevant for joineries
Preventive industrial processes/
storage of treated wood: assumptions
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1.5.2020
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Realistic worst-case:
• storage area is uncovered and unpaved
• default values for the parameter AREAwood-treated and
emission factors (F)
• default value for rainfall 3 rain events, 60 min each, every
third day, with a precipitation of 4 mm.h-1
=>
corresponds to 1460 mm.y-1; the leaching test should mimic
this rainfall pattern
Storage begins after post-treatment conditioning
Emissions are cumulative during the storage time and also
from the application phases
Degradation processes should be taken into account
Storage of treated wood: General equations
 Emission during application
Elocal  Qai  AREAwood treated  F
 Leaching during storage
Qleach,storage,time  FLUX storage  AREAwood exp o  AREAstorage  TIME
 Concentration in soil
Q
Clocal soil 
leach, storage,time
M soil
 Emission to surface water
Elocal surfacewater 
 (1  Frunoff )
Qleach, storage,time
TIME
 Frunoff
Storage of treated wood scenario:
example of input values and output
Input data
1.5.2020
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Results
*Qai = 15 g/m2
 Elocal = 0.9 kg/d
2
#AREAwood-treated = 2000 m /d
 Qleach,storage,time = 3.34 kg
#F = 0.03
 Clocalsoil = 124 mg/kg ww
*$FLUXstorage = 128 mg/m2/d
 Elocalsurfacewater = 0.056 kg/d
#AREAwood-expo = 11 m2/m2
#AREA storage = 79 m2
#TIME1 = 30 d
#Msoil = 13430 kg ww
#F runoff = 0.5
* Value to be set
# Default value
$ This is the leaching rate
Emission Scenario for automated spraying
Air drift
Generally roofed
Rain
Spray Box
Stored timber
wood
Drip pad
wood
WWTP
effluent
Surface water
Air deposition
estuary
o
soil
n-o
Mix Tank
influent
Ru
r
ff
Facility drain
ng
ecycli
Ground water
Automated spraying scenario:
assumptions
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1.5.2020
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Realistic worst-case:
• emissions to air occur directly due to spray drift / evaporation
from the spray box and from the treated wood after it
• cemented floors, run-off recycled; unintentional spills, floor &
equipment cleaning, washing waters etc. go to facility drain
=> to the sewage treatment plant
• default emission factors (F) depend on water solubility and
vapour pressure (given as pick-lists)
All industrial spraying applications covered, 2 plant sizes
Emission to surface water only via dry deposition; not yet
quantified
Emissions are cumulative from the application phases and
also during the storage time
Automated spraying scenario
Elocalair  AREAwood treated  Qai  ( Fair  Fdrift )
Elocal facilitydrain  AREAwood treated  Qai  F facilitydrain
Parameter/ variable
Symbol
Unit
Defaults
Wood area treated per day
AREAwood-treated
m2.d-1
2.000 or
20.000
Application rate: quantity of a.i.
applied per m2 of wood area
Qai
kg.m-2
Dossier
Fraction released to facility drain
Ffacilitydrain
-
from pick-list
Fraction released to air
Fair
-
from pick-list
Fraction of spray drift deposition
Fdrift
-
0.001
Local emission rate to air
Elocalair
kg.d-1
Local emission rate to facility drain
Elocalfacilitydrain
kg.d-1
Input:
Output:
Emission Scenario for automated dipping
Rain
Air
(mostly no roof)
Stored timber
wood
Drip pad
Dip Tank
recycling
wood
Facility drain
influent
WWTP
effluent
Surface water
estuary
Ru
noff
soil
Ground water
Automated dipping scenario:
assumptions and calculations
 All industrial and professional dipping / immersion
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1.5.2020
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applications covered: sawmills and joinery / carpentry
Assumptions and calculations are much the same as
for the spraying scenario; the differences are:
• no spray drift to air: emissions to air occur due to
evaporation from the dipping bath, co-distillation with
solvent and from saw dust / dried salts
• calculations based on volume of treated wood (100
m3.d-1) instead of area; conversion formulas provided
No direct emission to surface water from the process,
only from storage
Emission Scenario for industrial pressure processes
Air
Rain
roof
Stored timber
Pressur Vessel
wood
Drip pad
wood
(*)
Facility drain
recycling
influent
Mix Tank
WWTP
effluent
(*) relevantfor oil and organic
not relevantfor salt products
No 3:
off
Ru
n-
soil
Ground water
Surface water
EmissionScenario for vacuum pressure process(water borne, oil borne)
Industrial pressure processes scenario:
assumptions and calculations
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1.5.2020
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All industrial pressure applications covered with 2 plant
volumes
• vacuum pressure: wood volume treated per day 30 m3.d-1
• double-vacuum & low pressure: daily wood volume 15 m3.d-1
Assumptions and calculations are much the same as
for the spraying scenario; the differences are:
• no spray drift to air: emissions to air occur due e.g.
releases at cease of vacuum, evaporation losses,
aerosol air drifts and from saw dust / dried salts
• calculations based on volume of treated wood (see
above) instead of area
No direct emission to surface water from the process
Use classes of treated wood, the emission scenarios & relevant compartments
(
)
Scenarios for treated wood in service

4 relevant use classes with 10 detailed scenarios
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•
•
•
UC3 Wood not covered and not in contact with soil: 4
scenarios
UC4a Wood in contact with soil: 2 scenarios
UC4b Wood in contact with fresh water: 2 scenarios
UC5 Wood in contact with salt water: 1 scenario
House scenario represents a worst case compared
to the fence and noise barrier because of the
highest wood to soil ratio
•
Recommended to use the house scenario preferentially
• Use the fence scenario as a further option
1.5.2020
•
Noise barrier scenario resembles the fence but includes a
emission route to a sewage treatment plant (70% of
emission)
General assumptions in the
wood-in-service scenarios
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1.5.2020
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All scenarios require that leaching rate (FLUX [kg/m2/d]) be
established, e.g. from leaching tests
Cumulative amount leached over certain time (Q*leach,time
[kg/m2]) is estimated from FLUX
General equations used for emissions during storage apply
also for the scenarios of treated wood-in-service
Default values given for leachable treated wood area and
volumes of receiving compartments
The primary receiving environmental compartment is
considered to be soil or water (including STP)
Emissions to the air are considered negligible from
environmental point of view
Use class 3: Emission Scenario for Timber
Cladded House (with receiving soil compartment)
Timber Cladded House: assumptions
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1.5.2020
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The primary receiving environmental compartment is
considered to be soil via rain run-off
Leaching rates to be used should be from a test with wood
in direct contact with water
• Summary of test requirements is in Section 5.3.2.1 and
requirements for the design of such a leaching test is given in
Appendix 1
Emissions are cumulative over the assessment period,
therefore Clocal represents the concentration at the end of
the assessment time period
Emitted quantity calculated may be fed into groundwater
models
Timber Cladded House scenario
*
Qleach,time  AREAhouse  Qleach
,time
Clocal soil,leach,time 
Qleach,time
VsoilM
 RHO
soil soil
Parameter/ variable
Symbol
Unit
Defaults
Leachable wood area
AREAhouse
m2
125
Duration of assessment period
TIME1, TIME2
d
1: 30
2: to be set
Cumulative quantity of a.i. leached out of 1 m2 of
treated wood over the assessment period
Q*leach,time
kg.m-2
Dossier
Wet soil volume
Vsoil
m3
0.50
Bulk density of wet soil
Fair
kgwwt.m3
1700
Cumulative quantity of a.i. leached over the
assessment period
Qleach,time
kg
Concentration in local soil at the end of
assessment period
Clocalsoil,leach,time
kg.kgwwt-1
Input:
Output:
Timber Cladded House: example of
input values and results
Input data
1.5.2020
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AREAhouse = 125 m2
Soil “width” = 0.1 m (default)
Soil depth = 0.1 m (default)
Msoil = 850 kgww
TIME1 = 30 d
Q*leach,time1 = 1006 mg/m2
Results
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Qleach,time1 = 0.13 kg (over 30 d)
Clocalsoil,leach,time1 = 591
mg/kgww (D = 0.025 m)
Clocalsoil,leach,time1 = 147
mg/kgww (D = 0.1 m)
Clocalsoil,leach,time1 = 28
mg/kgww (D = 0.5 m)
Use class 3: Emission Scenario for noise barrier
(with receiving environmental compartments)
Use class 3: Emission Scenario for garden fence
(with receiving soil compartment)
Use class 4a: Emission Scenario for Transmission
Pole (with receiving soil compartment)
Transmission Pole scenario:
assumptions and calculations
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1.5.2020

Recommended to use the transmission pole scenario
preferentially
• Use the fence post scenario as a further option if e.g. required
due to preservative type
The primary receiving environmental compartment is soil which
has cumulative emissions from:
• rain run-off from above soil part of the pole
• permanent contact with the soil water phase for below ground part
Assumptions and calculations are much the same as for the
cladded house scenario; main differences are:
• separate above and below soil wood areas (5.5 and 1.6 m2)
• leaching rates to be used should be from a test with wood in direct
contact with water or in contact with soil (for below ground part only)
Use class 4a: Emission Scenario for fence post
(with receiving soil compartment)
Use class 4b: Emission Scenario for Jetty in
Lake (with receiving water compartment)
Jetty : 1.5 m wide, 8 m long.
Posts : 8, 2 m long, 20 cm diameter, 1 m in water.
Planks : 2.5 cm thick.
Supports : 5 cm thick, 20 cm wide
Primary Environmental
Compartment for Emissions
Fresh water : Lake 100 m diameter, 2m deep= 1.6 x
10 7 litres
Jetty in Lake scenario: assumptions
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1.5.2020
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For Use Class 4b, two scenarios available: jetty in a lake and a
sheet piling in a small stream or waterway
• The jetty scenario is a worst case with respect to the higher wood
surface area
• The sheet pilings scenario represents a worst case because of the
wood being exposed mainly under water
The primary receiving environmental compartment is a circular
pond which has cumulative emissions from:
• planks exposed to rain (usually treated for Use Class 3)
• poles all in permanent contact with water (treated for Use Class 4b)
Leaching rates to be used should be from a test with wood in
direct contact with water
General assumptions similar to the house scenario
Jetty in Lake scenario
*
Qleach,time  ( AREAplanks  AREApoles )  Qleach
,time
Clocal soil
water
,leach
,time 
,leach
,time
Parameter/ variable
Qleach,time
VM
water
soil
Symbol
Unit
Defaults
Leachable wood area: planks or poles
AREAplanks
AREApoles
m2
16.2
10.0
Duration of assessment period
TIME1, TIME2
d
1: 30
2: to be set
Cumulative quantity of a.i. leached out of 1 m2 of
treated wood over the assessment period
Q*leach,time
kg.m-2
Dossier
Water volume
Vwater
m3
1.6*104
Cumulative quantity of a.i. leached over the
assessment period
Qleach,time
kg
Concentration in local surface water at the
end of assessment period
Clocalwater,leach,time
kg.m-3
Input:
Output:
Use class 4b: Emission Scenario for sheet pilings in a
small streaming waterway
• There are 5 poles on both sides per meter waterway length.
• The waterway is 1 km long, 1.5 m deep and 5 m wide, with the residence
time of 20 days.
Use class 5
Emission Scenario for Harbour Wharf
• The wharf is 100 m
long with walling and
kerbing extending the
full length.
• The walling is doubled
at the front and back of
the fender piling.
• Piles with associated
rubbing strips are
spaced at 5 m intervals.
• The receiving
compartment is the
seawater at up to 5 m
distance from the wharf.
Wharf scenario: assumptions
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1.5.2020
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The primary receiving environmental compartment is salt
water in an intermediate-sized wharf
Seawater has cumulative emissions from:
• planks exposed to rain (usually treated for Use Class 3)
• poles all in permanent contact with seawater (treated for Use
Class 5)
The contact time of wood with the water and therefore the
concentration is determined by the water residence time
Leaching rates to be used should from a test with wood in
direct contact with seawater (submerged poles) and with
de-ionised water (planks above water)
Wharf scenario
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**




Qleach
Q
,time
leach,time
   AREApoles 
  TAUseawater
Qleach,time   AREAplanks 


TIME  
TIME 

Qleach,time
Clocal soil
seawater
,leach
,time 
,leach
,time
V
Mwater
soil
Parameter/ variable
Symbol
Unit
Defaults
Leachable wood area: planks or poles
AREAplanks
AREApoles
m2
Duration of assessment period
TIME1, TIME2
d
296
911
1: 30
2: to be set
Cumulative quantity of a.i. leached out of 1 m2
of treated wood over the assessment period
Q*leach,time
kg.m-2
Dossier: separate value
for poles and planks
Water volume along wharf
Vwater
m3
1000
Residence time of the seawater
TAUseawater
d
0.5
Cumulative quantity of a.i. leached over the
assessment period
Qleach,time
kg
Concentration in local seawater at the end of
assessment period
Clocalseawater,leach,time
kg.m-3
Input:
Output:
Potential exposure of environmental compartments
from professional and amateur in-situ treatments
Chapter 6
Accounting for removal processes
in water and soil
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Removal processes in the receiving compartment are
degradation, volatilisation, leaching to groundwater (for
soil) or sedimentation (in surface water)
In a first tier estimation these can be ignored (Ch. 4-6)
For a second tier the removal processes can be estimated
e.g. according to TGD and taken into account in the
estimation of the concentrations in water or soil
1.5.2020
• Guidance on how to calculate emissions from treated wood
as a function of time and taking into account removal
processes of the substance is given in Chapter 7
• The longer time span proposed: 1 year or longer (up to 10 yr)
General remarks on the ESD
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Guidance given on appropriate leaching tests for treated wood
and especially how to use different kind of leaching test
results
Some guidance given for calculation of the emissions from
treated wood that may reach groundwater in soil
•
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In the scenario description Tables, the input and output data
are divided into three groups:
•
•
•
1.5.2020
Applicability of PEARL and PELMO groundwater models discussed:
regarding scenarios for treated wood-in-service and storage
A: “data Set” data to be supplied by the notifier; no default value is set.
Note: Symbol “S” used for this group in the EU ESDs & spreadsheets
D “Default”
parameter has a standard value (most defaults can be
changed by the user);
O “Output”
parameter is the output from a calculation (most output
parameters can be overwritten by the user with alternative data);
Conclusions on the OECD ESD
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ESD covers use scenarios and environmental
compartments of (presumed) highest concern
Based on empirical data & default values but has not been
validated; only the applicability of the equations has been
tested
Can be used when no other overriding data are available
(c.f. TGD)
 Specific data on use pattern and emission rate should be
used by applicants whenever possible
Results from emission estimates should feed into exposure
assessment in accordance with the Technical Guidance
Document on risk assessment
1.5.2020
• combined with some generic emission estimates according to
the TGD
Revised TGD: relevant
exposure assessment issues
 More complete life cycle assessment
 Release estimation
• emissions from long-life articles
• emissions from waste disposal including
recovery
 Unintentional uses: calculation of
1.5.2020
background concentrations
Waste remaining in the environment
CHEMICAL PRODUCTION
PRODUCTION
INTERMEDIATES
- non-isolated intermediates
- isolated intermediates stored on-site
- isolated intermediates with controlled transport
CHEMICAL
USE
FORMULATION
PRIVATE USE
(article production)
<< PROCESSING >>
INDUSTRIAL USE
(article production)
ARTICLE
USE
ARTICLES
ARTICLES
SERVICE LIFE
Waste
remaining in the
environment
Urban soil
WASTE DISPOSAL
- Incineration
- Landfilling
- Recovery
Accumulation of long-life articles in the society


Service life > 1 year
EXAMPLE: Chemical X as an additive to a material in shoe
sole.
Steady state at year 2004
Service life of the shoe = 5 year
tonnes / year
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
year
Introduced to the market
= Annual input of X from production
= Remaining amount of X in the society year 2,3,4,5
(corrected for reduction due to emission)
Emissions from long life articles
CONTINENTAL / REGIONAL
SCALE
h
“Service life”
LOCAL SCALE
Explanation of symbols:
b
Land
fills
i
g
Accumulated amount of
substance X in the society
a
Acc. amount of X in “Waste
remaining in the environ."
c
j
k
AIR
f
SURFACE
WATER
e
URBAN /
IND. SOIL
d
Incineration
sites
STP
annual flow of substance X in form of articles / materials
annual flow of substance X in molecular form
Annual input from:
- “production”
- “formulation”
- “industrial / professional use”
Emission at Steady state when “input” = “output”
…for society:
a = [b + c + d + e + f + g + h]
…for “waste remaining in the environment”: h = [i + j + k]
Emissions scenario for long-life
articles

Calculations of diffuse emissions at regional /
continental scale
1)
2)
3)
4)
F < 1%/year  simplification

Local scale: for the municipal STP
•
•
1.5.2020
Estimate service life
Estimate emission factors (F)
Calculate accumulation
Calculate annual release
Indoor emissions
Outdoor emissions via storm water
(IC 5, Personal/Domestic)
Emission equations
Qtot_accum_steadystatek  Qtot k 
Tservicek
y 1
(
1

F
)
 i,total
y 1
Simplification when the emission factor is low
(<1 %/year):
1.5.2020
Qtot-accum_steady statek = Qtotk * Tservice
“Unintentional sources” /
Cumulative effects (TGD, Part II, App. XIII)


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The rapporteur should list other sources which can give
rise to exposure by the substance being assessed
• Evaluation report should include available information on
these sources: other PTs, non-biocidal uses
For biocides, only sources which include substances of
natural origin or releases from other biocidal uses should
be taken into account as “cumulative effects” in the risk
assessment
Cumulative effects are to be taken into account in the
PECregional which provides the background concentration
to be incorporated in the PEClocal
1.5.2020
• PECregional to be calculated with EUSES using generic
assumptions