latest version: 5.13

What's new

Please always refer to version number when you report MeClas classifications.

5.13 (09/04/2024)

  • Added KCO3 self-classification (and removed older entry K/K compounds)
  • Corrected bug (since 2020) that molecular weight correction was made twice in Tier 2 HH bio-accessbility calculation. Please refer to the bio-accessibility calculator for correct calculation.
  • Updated bio-accessability calculator version 3.1

5.12 (20/01/2023)

  • Improved output in case environment is Tier 1 and human health Tier 2 and vice versa.
  • Updated ERV values for Zn, Au, Pd, Pt, Re, Rh, Ru

5.11 (4/11/2022)

  • New self-classification for Sr, NiS, Ni3S2
  • Improved MARPOL classification output
  • New Composition type "Mixtures"

5.10 (21/01/2022)

  • Added fertility and/or development subscripts (FD) for reprotoxicity where relevant
  • Splitted respiratory and skin sensitization endpoints into seperate categories.

5.9 (5/11/2021)

  • Added several cobalt and nickel carboxylates/dinitrate to the database

5.8 (6/09/2021)

  • Addes PbO and PbCl2 species
  • Added inhalation H350i, H351i for carcinogenicity
  • Updated ERV for arsenic, nickel and silver
  • Improved "edit composition" layout more clearly highlighting rows for elemental concentration, TDP or bio-accessibility correction 

5.7 (25/03/2021)

  • Updated ERV Vanadium
  • Specific concentration limits for borates removed (17th ATP)

5.6 (2/11/2020)

  • Update M-factors Pb powder classifications following 15th ATP
  • Update As massive and powder, As2O3 self-classification (Repro and STOT)

5.5 (16/04/2020)

  • First tutorial video on MeClas published in the help section.
  • Eurometaux Guidance on classification of inorganic UVCB substances for human health hazards published
  • Updated relative bioaccessiblity calculator published
  • Added Ba silicate, Zn silicate, K silicate and Na silicate
  • Update Co metal classifications following 14th ATP

5.4 (11/11/2019)

  • New functionality "Virtual ingredients" now available.

5.3 (12/07/2019)

  • Added additional menu button "Background database"
  • Improved Tier 2 bio-accessibility calculations making distinction between "all routes" and "inhalation route" for carcinogenicity and STOT Re.
  • Updated NiCl2 Repr 1B classification (bug fix), Added CaF2, NaF, AlF4Na3

5.2 (07/12/2018)

  • Added additional menu button "adapt reference composition"
  • In and several In compounds, Sr and SrO, HBF4 were added to the database
  • Additional input functionality for Ores and Concentrates (type TDP on O&C) via excel template
  • Amended NiCO3 following 1st ATP and CaSO4
  • Update Zn(OH)2 and CoO classification

5.1 (19/06/2018)

  • Distinction between As massive and As powder and updated self-classification
  • Added GeO2 to database
  • Added effects for lactation category

5.0 (8/05/2018)

  • Improved graphical user-interface
  • Tier 2 human health correction (SWERF) for SiO2
  • Easy composition copy/paste functionality
  • Filtering options across and within compositions
  • Extended intermediate calculations
  • In order to facilitate the addition of further modules (regional ones), the longer term sustainability of the tool, easier maintenance and updates, an improved IT architectural design was implemented.

4.5 (5/2/2018)

  • Updated classifications for Cu compounds following 9th ATP.

4.4 (5/2/2018)

  • Updated classifications for Co compounds and updated ERVs for Cu and Co.

4.3 (20/9/2017) 

  • Updated classifications for covelite, chalcocite, bornite, digenite, tennantite (due to changes in Cu ERV).

4.2 (15/3/2017)

  • Updated classification Repro 1A and STOT 1 for massive lead. Updated SCL Repro 1A >0.03% for lead powder.
  • Updated ERVs for copper, bismuth, chromium, manganese, mercury and tin.

4.2 (24/01/2017)

  • Updated classification Repro 1A and STOT 1 for massive lead. Updated SCL Repro 1A >0.03% for lead powder..

4.1 (08/03/2016)

  • New entries for Cobalt massive and Cobalt respirable powder. Updated classification for Co(Cl)2, Co(NO3)2, CoSO4, CoCO3, CoO, Co(OH)2, CoS.

4.0 (15/09/2015)

  • New alloys module added. New classification modules under GHS and US.
  • Improved web user interface.
  • Updated User Manual.
  • Cu(OH)2 added to the background database.


  • Co is now considered as removed from the water column.
  • Bug on CoSO4, CoCO3 and CoCl2 molecular weight is fixed.

3.1 (9/01/2015)

  • Additional information on the mixture formulae used is added to the in-between calculations page (accessible via the blue "i"-button in "calculate classification").
  • Furthermore, a small error in the CLP Eye irritation Cat 2 formulae and the GHS skin irritation Cat. 3 formulae was corrected.

3.0 (15/12/2014)

  • A new module is finalised to classify ores and concentrates (based on TDP on minerals), to adapt ores/concentrates reference samples, to classify according to MARPOL criteria (Hazardous to the marine environment).
  • The background database was also updated for Pb compounds (SCL for STOT Cat. 2 removed).

2.8 (26/09/2014)

  • The background database was updated with R50-53 for Cu powder.
  • New entries were added for ZnSeO3, SeO2 and Na2SeO4. The entries for Te and TeO2 were updated.

2.7 (11/06/2014)

  • The background database was updated with carc 1B self-classification for Co metal and minor changes for BaS and Na (following updates notified to Eurometaux or updates in self-classification ECHA dissemination website 2013 registrations).
  • ERVs were updated or added for Ce, Co, Li, Mg, W, Zr and V. GaAs was added to the database (5th ATP harmonised classification).
  • Lastly, it is possible in Tier 2 environmental classification to specify the pH of the TDP test. pH-dependent ERVs are now used for those metals that have them.

2.6 (16/12/2013)

  • The output pfd and excel generation was supplemented with additional "in-between" supportive calculations information.
  • CdS.ZnS and NiAs was added to the background database.

2.5 (20/08/2013)

  • Implementation of additional mixture rule for skin corrosion and eye damage: combinations of generic and specific concentration limits are now possible due to increase number of specific concentration limits in the background database.
  • Molecular weight of CaO was corrected to 56.0778.

2.4 (1/08/2013)

  • HCl (aq), NiCl2, Ag2SO4, AgNO3 (aq), inorganic carbon (compounds) were added to the database.
  • ERV for Ni, B, Mo, Se and Au are updated. ERVs for Hg are added.

2.3 (18/07/2013)

  • Cd is now also considered as removed from water column.
  • S, Re, Re compounds, Na2Se, CuCl, Cu2Te, TeO2, H2PdCl4, HAuCl4n have been added to the database.
  • Additional DSD specific concentration limits for acute toxicity were added.

2.2 (26/02/2013)

  • Ni is now also considered as removed from water column.
  • Note 1 ("The concentration stated or, in the absence of such concentrations, the generic concentrations of this Regulation (Table 3.1) or the generic concentrations of Directive 1999/45/EC (Table 3.2), are the percentages by weight of the metallic element calculated with reference to the total weight of the mixture.") was implemented for CoCl2, Co(NO3)2, CoSO4, CoCO3 and CdS.

2.1 (6/02/2013)

  • Specific concentrations limits for STOT Pb compounds were updated.

2.0 (15/12/2012)

  • 2nd ATP updated mixture ruling for environment and sensitization
  • Updated background database: ERV changes for Mn, Sb, As, classification changes for Cu compounds, Sb2S3, Mn compounds
  • Improved bio-elution correction for the oral route
  • Inclusion of removal from the water column concept as part of the environmental classification (Cu, Al, Sb, Pb, Zn, Fe, Cr, Sn)
  • Inclusion of UN GHS mixture ruling and classification output
  • Inclusion of ores and concentrates module (currently under testing) allowing mineral specific bio-availability correction

1.9 (28/11/2012)

  • Metals that are considered to be removed from water column (Pb, Cu and Zn). Background database updated to multimetallic database (version end october 2012).

1.8 (25/10/2012)

  • Metals that quickly hydrolyse and form different species that precipitate in the water column (Fe, Al, Sb, Sn, Mo and Cr) are removed from the water column and rapidly degradable. Amended in database (impact on Tier 2 environmental classifications)

1.7 (22/08/2012)

  • The self-classifications for Cu and Cu compounds are updated based on 28d TDP testing. Additional entries are made for some Cu-minerals.

1.6 (13/07/2011)

  • The self-classifications from the MECLAS background database were compared with the proposed classifications from the ECHA dissemination website (from lead registrant dossiers). The majority of the self-classifications were compliant. For some metal (compounds), differences were identified and where appropriate, the MECLAS background database was updated. This was the case for the following substances: Ba, BaS, BaCO3, BaO2, Ba salts (with the exception of BaSO4 and other Ba salts specified elsewhere in Annex VI), BaSO4, Bi, Ce/Ce compounds, Cr, Cr silicate, Cr2O3, CrS and CrSO4, Hg/Hg compounds, La, Mn, MnO2, Na2S, Nb/Nb compounds and Ti. New self-classifications were added for BaCl2, Ba(OH)2, Bi(NO3)3, CdCl2, CoCl2, LaCl3, Mn(NO3)2, TiCl4, ZrOCl2, ZrCl4 and AgO2. In some cases, the Registrant did not foresee any environmental hazard classification for the metal and its poorly soluble compounds while the soluble compounds for the same metal are classified for this endpoint under CLP. CLP guidance (Chapter 4 annex 4) foresees that metals and poorly soluble metals should be classified by default as category “chronic 4” in absence of dissolution kinetics data measured with the standard Transformation Dissolution protocol (see Annex 10 of the GHS), if the metal ion expresses toxicity (< 100 mg/l).
  • To improve transparency, the MECLAS background database with official and self-classifications and (acute) M-factors is now available for all MECLAS users. Check it out under the "Tool" menu. Note that ERV-values are still kept confidential at this moment.
  • User input on the composition of materials is now automatically quality screened and warning messages are shown where appropriate.
  • Additional endpoints were added under DSD: 'Non lethal irreversible effects after single exposure' and 'Severe effects after repeated or prolonged exposure' (similar to STOT RE en STOT SE onder CLP)?

1.5 (21/12/2010)

  • The European Copper Institute (ECI) has released the self-classification of several CuS-minerals (chalcocite, diginite and chalcopyrite) which can be selected in Tier 1.
  • Based on testing on removal from the water column, the self-classifications of Cu compounds have been updated. These compounds (except CuSO4 and Cu2O which have Annex VI entries) no longer have a chronic environmental classification. These updates can alter (improve) environmental classifications.
  • Comprehensive transformation/dissolution and speciation data are also now available for copper ores and concentrates. To access the translation factors, required for consistency with the classification notification submitted to ECHA on December 17th, please contact ECI directly, at

1.4 (16/12/2010)

  • The MECLAS Tier 2 is further updated. As more users are using this tier, some guidance was developed on how to incorporate TDP and/or bio-elution test results in MECLAS (see Technical Manual section 3.1.1, p. 13-15). Two small supporting excel tools were developed and can be downloaded to calculate the proper translation factor.


  • Several additional existing official classification from AnnexVI and 1st ATP.


  • Thanks to IMA Europe, the self classifications for several IMA substances have been added to MECLAS (lime substances, boric acid, diboron trioxide, disodium tetraborates and respirable quartz and cristobalite). There is also a dedicated website related to respirable crystalline silica: Check out the classification and labelling section.
  • The environmental classification was split into acute and chronic endpoints
  • The list of M-factors was updated. The list was send around to all MECLAS users


You must register in order to access the MeClas tool and all supporting information. A short description of the Terms of conditions can be downloaded. The manual gives an idea on the basic functionalities of MeClas.


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