Concentration models tiers

In addition to the possibility for users to work with their own choices for all settings, MCRA implements four tiers from two documents:

  • The optimistic and pessimistic basic assessments from the EFSA 2012 Guidance on the Use of Probabilistic Methodology for Modelling Dietary Exposure to Pesticide Residues (EFSA (2012)).

  • Tier 1 and 2 from the European Commission working document SANTE-2015-10216 rev. 7 (2018) on risk management aspects related to the assessment of cumulative exposure (EC (2018)).

Overview

Table 47 Tier overview for module Concentration models.
Name EFSA 2012 Optimistic EFA 2012 Acute Pessimistic EFA 2012 Chronic Pessimistic EC 2018 Acute - Tier I EC 2018 Acute - Tier II EC 2018 Chronic - Tier I EC 2018 Chronic - Tier II EFSA 2022 Acute Tier I EFSA 2022 Acute Tier II EFSA 2022 Chronic Tier I EFSA 2022 Chronic Tier II

Default concentration model

Empirical

NonDetectSpikeLogNormal

NonDetectSpikeLogNormal

Empirical

Empirical

Empirical

Empirical

Empirical

Empirical

Empirical

Empirical

Include MRL fallback model

false

true

true

false

false

false

false

false

false

false

false

Censored values replacement

ReplaceByZero

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

ReplaceByLOR

Sample based

true

true

true

true

true

true

true

true

true

true

true

Impute missing values from available values (if unchecked, missing values are imputed with 0)

false

true

true

true

true

true

true

true

true

true

true

Correlate imputed values with sample potency

false

true

true

true

false

true

false

true

false

true

false

Use occurrence frequencies for imputation

false

true

true

true

true

true

true

true

true

Parametric uncertainty

false

true

false

false

false

false

false

false

false

false

false

Restrict LOR imputation to authorised uses

false

false

false

false

false

false

false

false

false

false

Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD)

1

1

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

MRL Factor (f x MRL)

1

1

Apply occurrence pattern percentages

false

true

false

true

false

true

false

true

Substance conversion method

UseMostToxic

DrawRandom

UseMostToxic

DrawRandom

UseMostToxic

DrawRandom

UseMostToxic

DrawRandom

Retain all allocated substances after active substance allocation

true

true

true

true

true

true

true

true

Account for substance authorisations in substance conversions

false

true

false

true

false

true

false

true

Fix duplicate substance allocation inconsistencies

false

false

false

false

false

false

false

false

Use extrapolation rules

true

true

true

true

false

false

false

false

Threshold for extrapolation

10

10

10

10

Restrict extrapolations to equal MRLs

true

true

true

true

Restrict extrapolations to authorised uses

true

true

true

true

Impute water concentrations

true

true

true

true

true

true

true

true

Water concentration value (µg/kg)

0.1

0.05

0.1

0.05

0.1

0.05

0.1

0.05

Restrict water imputation to the five most toxic substances

true

true

true

true

true

true

true

true

Restrict water imputation to authorised uses

false

false

false

false

false

false

false

false

Restrict water imputation to approved substances

false

false

false

false

true

true

true

true

Scale up use frequency to 100%

true

true

true

true

Restrict use percentage up-scaling to authorised uses

true

true

true

true

Use substance conversion rules

true

true

true

true

The sections below describe the settings specified by each tier in detail.

Retrospective dietary CRA (EFSA 2012) - Optimistic

Concentration model settings according to the optimistic scenario of the EFSA 2012 methodology for dietary exposure assessments. Censored values and missing values are replaced by zero.

Table 48 Tier definition for Retrospective dietary CRA (EFSA 2012) - Optimistic.
Name Setting

Default concentration model

Empirical

Include MRL fallback model

false

Censored values replacement

ReplaceByZero

Sample based

true

Impute missing values from available values (if unchecked, missing values are imputed with 0)

false

Correlate imputed values with sample potency

false

Use occurrence frequencies for imputation

false

Parametric uncertainty

false

Retrospective dietary CRA (EFSA 2012) - Acute / Pessimistic

Concentration model settings according to the pessimistic scenario of the EFSA 2012 methodology for acute dietary exposure assessments. A censored value spike lognormal model is fitted to the positive residue values and censored values are replaced by the LOR. When the number of positives is smaller than 2, the maximum residue limit (if available) is used instead. Missing values are imputed.

Table 49 Tier definition for Retrospective dietary CRA (EFSA 2012) - Acute / Pessimistic.
Name Setting

Default concentration model

NonDetectSpikeLogNormal

Include MRL fallback model

true

Restrict LOR imputation to authorised uses

false

Censored values replacement

ReplaceByLOR

Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD)

1

MRL Factor (f x MRL)

1

Sample based

true

Impute missing values from available values (if unchecked, missing values are imputed with 0)

true

Correlate imputed values with sample potency

true

Parametric uncertainty

true

Retrospective dietary CRA (EFSA 2012) - Chronic / Pessimistic

Concentration model settings according to the pessimistic scenario of the EFSA 2012 methodology for chronic dietary exposure assessments. A censored value spike lognormal model is fitted to the positive residue values and censored values are replaced by the LOR. When the number of positives is smaller than 2, the maximum residue limit (if available) is used instead. Missing values are imputed.

Table 50 Tier definition for Retrospective dietary CRA (EFSA 2012) - Chronic / Pessimistic.
Name Setting

Default concentration model

NonDetectSpikeLogNormal

Include MRL fallback model

true

Restrict LOR imputation to authorised uses

false

Censored values replacement

ReplaceByLOR

Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD)

1

MRL Factor (f x MRL)

1

Sample based

true

Impute missing values from available values (if unchecked, missing values are imputed with 0)

true

Correlate imputed values with sample potency

true

Parametric uncertainty

false

Retrospective dietary CRA (EC 2018) - Acute / Tier I

Table 51 Tier definition for Retrospective dietary CRA (EC 2018) - Acute / Tier I.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency true
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages false Retrospective dietary CRA (EC 2018) - Acute / Tier I Occurrence patterns
Substance conversion method UseMostToxic Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Account for substance authorisations in substance conversions false Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Use extrapolation rules true Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Threshold for extrapolation 10 Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Restrict extrapolations to equal MRLs true Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Restrict extrapolations to authorised uses true Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Impute water concentrations true Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Water concentration value (µg/kg) 0.1 Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations
Restrict water imputation to approved substances false Retrospective dietary CRA (EC 2018) - Acute / Tier I Concentrations

Retrospective dietary CRA (EC 2018) - Acute / Tier II

Table 52 Tier definition for Retrospective dietary CRA (EC 2018) - Acute / Tier II.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency false
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages true Retrospective dietary CRA (EC 2018) - Acute / Tier II Occurrence patterns
Scale up use frequency to 100% true Retrospective dietary CRA (EC 2018) - Acute / Tier II Occurrence patterns
Restrict use percentage up-scaling to authorised uses true Retrospective dietary CRA (EC 2018) - Acute / Tier II Occurrence patterns
Substance conversion method DrawRandom Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Account for substance authorisations in substance conversions true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Use extrapolation rules true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Threshold for extrapolation 10 Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Restrict extrapolations to equal MRLs true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Restrict extrapolations to authorised uses true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Impute water concentrations true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Water concentration value (µg/kg) 0.05 Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations
Restrict water imputation to approved substances false Retrospective dietary CRA (EC 2018) - Acute / Tier II Concentrations

Retrospective dietary CRA (EC 2018) - Chronic / Tier I

Table 53 Tier definition for Retrospective dietary CRA (EC 2018) - Chronic / Tier I.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency true
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages false Retrospective dietary CRA (EC 2018) - Chronic / Tier I Occurrence patterns
Substance conversion method UseMostToxic Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Account for substance authorisations in substance conversions false Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Use extrapolation rules true Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Threshold for extrapolation 10 Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Restrict extrapolations to equal MRLs true Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Restrict extrapolations to authorised uses true Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Impute water concentrations true Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Water concentration value (µg/kg) 0.1 Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations
Restrict water imputation to approved substances false Retrospective dietary CRA (EC 2018) - Chronic / Tier I Concentrations

Retrospective dietary CRA (EC 2018) - Chronic / Tier II

Table 54 Tier definition for Retrospective dietary CRA (EC 2018) - Chronic / Tier II.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency false
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Occurrence patterns
Scale up use frequency to 100% true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Occurrence patterns
Restrict use percentage up-scaling to authorised uses true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Occurrence patterns
Substance conversion method DrawRandom Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Account for substance authorisations in substance conversions true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Use extrapolation rules true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Threshold for extrapolation 10 Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Restrict extrapolations to equal MRLs true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Restrict extrapolations to authorised uses true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Impute water concentrations true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Water concentration value (µg/kg) 0.05 Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations
Restrict water imputation to approved substances false Retrospective dietary CRA (EC 2018) - Chronic / Tier II Concentrations

Retrospective dietary CRA (EFSA 2022) - Acute / Tier I

Table 55 Tier definition for Retrospective dietary CRA (EFSA 2022) - Acute / Tier I.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency true
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages false Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Occurrence patterns
Use substance conversion rules true Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Substance conversion method UseMostToxic Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Account for substance authorisations in substance conversions false Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Use extrapolation rules false Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Impute water concentrations true Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Water concentration value (µg/kg) 0.1 Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations
Restrict water imputation to approved substances true Retrospective dietary CRA (EFSA 2022) - Acute / Tier I Concentrations

Retrospective dietary CRA (EFSA 2022) - Acute / Tier II

Table 56 Tier definition for Retrospective dietary CRA (EFSA 2022) - Acute / Tier II.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency false
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Occurrence patterns
Scale up use frequency to 100% true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Occurrence patterns
Restrict use percentage up-scaling to authorised uses true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Occurrence patterns
Use substance conversion rules true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Substance conversion method DrawRandom Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Account for substance authorisations in substance conversions true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Use extrapolation rules false Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Impute water concentrations true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Water concentration value (µg/kg) 0.05 Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations
Restrict water imputation to approved substances true Retrospective dietary CRA (EFSA 2022) - Acute / Tier II Concentrations

Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I

Table 57 Tier definition for Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency true
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Occurrence patterns
Use substance conversion rules true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Substance conversion method UseMostToxic Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Account for substance authorisations in substance conversions false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Use extrapolation rules false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Impute water concentrations true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Water concentration value (µg/kg) 0.1 Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations
Restrict water imputation to approved substances true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier I Concentrations

Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II

Table 58 Tier definition for Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II.
Name Setting From input tier In module
Default concentration model Empirical
Include MRL fallback model false
Restrict LOR imputation to authorised uses false
Censored values replacement ReplaceByLOR
Factor f (f x LOR or f x LOD or LOD + f x (LOQ - LOD) 0.5
Sample based true
Impute missing values from available values (if unchecked, missing values are imputed with 0) true
Correlate imputed values with sample potency false
Use occurrence frequencies for imputation true
Parametric uncertainty false
Apply occurrence pattern percentages true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Occurrence patterns
Scale up use frequency to 100% true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Occurrence patterns
Restrict use percentage up-scaling to authorised uses true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Occurrence patterns
Use substance conversion rules true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Substance conversion method DrawRandom Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Retain all allocated substances after active substance allocation true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Account for substance authorisations in substance conversions true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Fix duplicate substance allocation inconsistencies false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Use extrapolation rules false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Impute water concentrations true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Water concentration value (µg/kg) 0.05 Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Restrict water imputation to the five most toxic substances true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Restrict water imputation to authorised uses false Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations
Restrict water imputation to approved substances true Retrospective dietary CRA (EFSA 2022) - Chronic / Tier II Concentrations