Concentrations tiers

In addition to the possibility for users to work with their own choices for all settings, MCRA implements 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.

Overview

Table 57 Tier overview for module Concentrations.

Name	EC 2018 Tier 1	EC 2018 Tier 2
Substance conversion method	UseMostToxic	DrawRandom
Retain all allocated substances after active substance allocation	true	true
Account for substance authorisations in substance conversions	false	true
Use extrapolation rules	true	true
Threshold for extrapolation	10	10
Restrict extrapolations to equal MRLs	true	true
Restrict extrapolations to authorised uses	true	true
Impute water concentrations	true	true
Water concentration value (µg/kg)	0.1	0.05
Restrict water imputation to the five most toxic substances	true	true
Restrict water imputation to authorised uses	false	false

EC 2018 Tier 1

Table 58 Tier definition for EC 2018 Tier 1.

Name	Setting
Substance conversion method	UseMostToxic
Retain all allocated substances after active substance allocation	true
Account for substance authorisations in substance conversions	false
Use extrapolation rules	true
Threshold for extrapolation	10
Restrict extrapolations to equal MRLs	true
Restrict extrapolations to authorised uses	true
Impute water concentrations	true
Water concentration value (µg/kg)	0.1
Restrict water imputation to the five most toxic substances	true
Restrict water imputation to authorised uses	false

EC 2018 Tier 2

Table 59 Tier definition for EC 2018 Tier 2.

Name	Setting
Substance conversion method	DrawRandom
Retain all allocated substances after active substance allocation	true
Account for substance authorisations in substance conversions	true
Use extrapolation rules	true
Threshold for extrapolation	10
Restrict extrapolations to equal MRLs	true
Restrict extrapolations to authorised uses	true
Impute water concentrations	true
Water concentration value (µg/kg)	0.05
Restrict water imputation to the five most toxic substances	true
Restrict water imputation to authorised uses	false