Using REACH PBT Assessment What is the purpose of the REACH PBT & vPvB Assessment? - REACH requires for every substance to be registered and not exempted a PBT & vPvB Assessment if the tonnage exceeds 10 tons/year - The REACH PBT & vPvB Assessment allows a straightforward, user friendly and quick assessment if the necessary information is available - An important goal is to rapidly identify those REACH substances which are not PBT & vPvB. In addition those substances identified as a potential PBT or vPvB can immediately investigated in a higher tier assessment to find out what is necessary as a next step. Such higher tier assessments are very often time consuming and costly and it has to be avoided that the strict registration deadlines cannot be met due to an ongoing PBT assessment - As the assessment is done transparently and always the same way it will allow a standardized PBT & vPvB Assessement throughout Clariant independant from personal judgments of an assessor - Printing the result sheet e.g. as a PDF file allows proper documentation of the PBT & vPvB Assessment in the Clariant REACH DMS What are the elements of REACH PBT & vPvB Assessment? - REACH PBT & vPvB encompasses all elements of the PBT & vPvB Assessment under REACh addressing available Assessment criteria as well as Tests and results, QSAR estimates and Read across from similar subst. How are the data used for REACH PBT & vPvB Assessment? - Available test result in the assessment are ranked according the relevance for the assessment - The ranking is independent from the personal judgment of the assessor and the Assessment result as well Which substance can be assessed? - Organic substances only, no inorganics, no organometallics, no polymers, no mixtures
Transcript
Using REACH PBT Assessment
What is the purpose of the REACH PBT & vPvB Assessment?
- REACH requires for every substance to be registered and not exempted a PBT & vPvB Assessment if the tonnage exceeds 10 tons/year
- The REACH PBT & vPvB Assessment allows a straightforward, user friendly and quick assessment if the necessary information is available
- An important goal is to rapidly identify those REACH substances which are not PBT & vPvB. In addition those substances identified as a potential PBT or vPvB can immediately investigated in a higher tier assessment to find out what is necessary as a next step. Such higher tier assessments are very often time consuming and costly and it has to be avoided that the strict registration deadlines cannot be met due to an ongoing PBT assessment
- As the assessment is done transparently and always the same way it will allow a standardized PBT & vPvB Assessement throughout Clariant independant from personal judgments of an assessor
- Printing the result sheet e.g. as a PDF file allows proper documentation of the PBT & vPvB Assessment in the Clariant REACH DMS
What are the elements of REACH PBT & vPvB Assessment?
- REACH PBT & vPvB encompasses all elements of the PBT & vPvB Assessment under REACh addressing available Assessment criteria as well as Tests and results, QSAR estimates and Read across from similar subst.
How are the data used for REACH PBT & vPvB Assessment?
- Available test result in the assessment are ranked according the relevance for the assessment
- The ranking is independent from the personal judgment of the assessor and the Assessment result as well
Which substance can be assessed?
- Organic substances only, no inorganics, no organometallics, no polymers, no mixtures
How is REACH PBT & vPvB Assessment organized?
- It consists of 5 Worksheets: Substance, P-Sheet, B-Sheet, T-Sheet, and
- Data input is allowed in pale yellow / orange cells, all other cells are write protected
Results
- All input data can be cleared by pressing SHIFT+CTRL+C
- Some input field can only be filled using Pick lists
What is the difference between REACH PBT & vPvB Assessment and the US EPA PBT Profiler?
- The US EPA PB Profiler (http://www.pbtprofiler.net) requires a CAS No. And/or a chemical structure only which allows to estimate the P, B and T Properties with help of the QSARs built in US EPI Win Modeling Suite.
- The REACH PBT & vPvB use measured, estimated or read across data for the PBT Assessment and addresses the EU Authorities position that some QSARs e.g. the BCF and Biodegradation QSARs are too optimistic in their estimates.
What is the prerequisite for using REACH PBT & vPvB Assessment?
- Basic knowledge on Persistency, Bioaccumulation and Toxicity is required. This assessment should not be used by people ignorant in the field of P, B and T Assessment
Screenshots of the worksheets in REACH PBT & vPvB Assessment
Substance
P-Sheet
B-Sheet
T-Sheet
Result
General Guidance for Data input
Input fields are pale yellow/orange and can be accessed by clicking in the field.
- Filling of fields
o By direct data input (some fields allow text and number input, some require number input > 0 only, hints are given by comments attached to the fields.
o From a Pick list of values received by clicking on the arrow which might appear when clicking in the field.
- Data format
o Some fields require numbers > 0 like 8.9 but not > 8.9 (this is regarded as text in EXCEL ™) as otherwise no meaningful results can be calculated (often an “ambiguous” is given in following fields or a direct error message).
- Meaning of fields
o Very often a Comment is attached to the field visible as red triangle in the upper right corner of the field. Hovering with the mouse pointer over such fields with comments displays the comment.
The pale yellow fields in REACH PBT Assessment allow direct data input with both numbers and text, where the orange fields in REACH PBT Assessment allow direct data input with numbers > 0 only.
Direct data input – numbers & text allowed Is not used for calculations but required in the context
Direct data input – numbers > 0 only Field is checked for text e.g. <or> etc. If field contains text, the text will be deleted automatically and only the numbers remained
Data input via Pick list Only the given pick list elements are valid input; If empty the endpoint is not considered in the assessment
Wrong Data format
CORRECT
data input format
WRONG
– Negative number is not allowed
data input format case 1
WRONG
– Symbols like ‘<’ or ‘>’ are not allowed
data input format case 2
TIP: REACH PBT Assessment v2.1.0 checks for invalid data input format (as listed above) during data inputting process and corrects automatically if any wrong format has been detected.
Thus, both wrong data input format cases (case 1 and case 2) shown above will be “self corrected” by eliminating any text or symbols right after data inputting process has finished.
Substance Sheet
Starting a new PBT & vPvB Assessment
To create a new PBT workbook, double click Workflows > New
The PBT workflow window will indicate whether the new PBT workbook has been successfully created:
TIP: By default, you will be at the substance page after you created a new PBT workbook. If not, press SUBSTANCE tab from the horizontal menu.
Clearing input data in the entire Worksheet
To clear all the input data in the entire worksheet (substance sheet, P-, B- & T sheet and result sheet), double click Workflows > New, in the pop-up window, choose Yes, ignore changes then Next >.
The workflow shall be as follows:
Substance identification
It is recommended to insert the substance name, the CAS No. and the chemical structure to allow a precise identification of the substance being assessed.
Fields for Specific Assessments
- Certain substances substances like Organic Pigments, Antioxidants etc show reduced bioaccumulation due to their intrinsic properties like size, mol weight, octanol - and water solubility. In order to allow the assessment of reduced bioaccumulation the following specific input data may be required:
o Mol weight
o Molecular diameter Dmax
o Water solubility
o Octanol solubility
- In addition if the “Critical Body Approach” needs to be applied it has to be stated if the toxic “Mode of Action” is narcotic or not (chosen from the pick list)
- If the substance data mentioned above are not provided, none of these approaches can be applied by the assessment; on the other hand for usual organic chemicals of low molecular weight, small size and solubility not being exceptionally low, these data are not required.
Substance Remark
Use this field to describe exceptional properties of the substance assessed.
TIP: Drawing tool JChemPaint is used if manual drawing of the substance structure is needed. Click on the Structure diagram drawing area to start JChemPaint in the pop up window.
3D structure viewer is available now in REACH PBT & vPvB Assessment v2.1.0. To view the substance structure in 3D, press 3D tab next to structure diagram.
Log Coct/Cwater Approach & Critical Body Burden Approach
“Mode of Action” field
The Critical Body Burden Approach implemented here can only applied to substances with narcotic Mode of Action (MoE), no results is displayed in B Sheet if MoE is not
Persistency Assessment (P-Sheet)
General information
- The Persistency Check if related to Biodegradation and to Abiotic Degradation
- The Section Biodegradation has data input possibilities for
o MEASURED Data
Ready tests (Freshwater & Seawater) – most often available
Inherent test (only if substance is not sorbing: Elimination after 3h < 20% and pass level reached after 7d already, see EU PBT Guidance) – limited applicability
Simulation tests (measured Degradation half-life in different environmental compartments like freshwater, marine water, sediment, soil etc.) – most appropriate but rarely available (expensive testing)
o ESTIMATED and READ ACROSS Data
A worst case approach is taken, estimations/read across ‚ready biodegradability‘ is not accepted (ambiguous result) as the QSAR / Read across may be too optimistic.
- The Section Abiotic Degradation is related to measured Hydrolysis only
Assessment Strategy
- Fill the pale yellow/orange input fields from left to right, select Test type and Criteria from pick lists
- When possible use measured data, fill one or more lines if appropriate
- When QSAR or Read across is used, the P Result shown might be ambiguous (if ready biodegradability is assumed). In such a case carry out a ready test if no other data are available
- If Hydrolysis half-life at pH 4, 7 or 9
o is < 40 d the substance is not persistent but the hydrolysis products need to be checked if PBT or vPvB
o If Hydrolysis half-life at pH 4, 7 or 9 is >= 40d the P result is ambiguous as the substance might still be biodegradable, carry out a ready test if no other data are available
- Mesured data take precendence over QSAR / Read across, within measured data Similation test have a higher score than ready and inherent test (details on scoring see Annex 2)
- Overall P Assessment Result
o Not persistent based on measured data or based on estimated data (QSAR or Read across)
o Pesistent based on on measured data or based on estimated data (QSAR or Read across)
o ‘P Assessment’ failed due to insufficient / conflicting data
Example for data filling and Results
- Data input for a ‘ready result’ and an assessment result
- Overall P Assessment Result
Data input
Assessment example
Overall P Assessment Result
1
Select the Guideline from pick
list
2
Insert Test duration
(numbers & text)
3
Select associated
Pass criteria from pick
list
4 5
Results calculated by REACH PBT & vPvB Assessment tool
6
Insert reference of
the study report
Workflow
Biodegradation Input Measured
Data
Biodegradation Estimated data
input
Abiotic degradation
Measured data input
Bioaccumulation Assessment (B-Sheet)
General Information
- The Section Quantitative Bioaccumulation has data input possibilities for
o MEASURED DATA
Measured BCF – currently related to Fish BCF and Fish Dietary Studies resulting in a measured BCF
Measured log Kow / log Coct/Cwater - from classical OECD Tests (see pick list in Worksheet) or calc. From measured octanol - and water solubility
o ESTIMATED Data
Calculated log Kow using the US EPA KowWiN QSAR The user need carefully consider the applicability of the QSAR to his / her substance (this QSAR is e.g. not applicable for Pigments, Perfluoro chemcials)
- The Section Qualitative Indicators for Bioaccumulation
o Addresses the reduced bioaccumulation observed in lipid of biota
For substances with high Molecular weight (e.g. 700 / 1100 g/Mol) in combination to a large molecular cross sectional diameter e.g. Antioxidants
For substance with low solubility in water and octanol e.g. Pigments resulting in a low log Coct/Cwater or an octanol solubility lower than the Critical Body Burden for substances with narcotic toxic mode of action
Assessment Strategy
- Fill the pale yellow / orange input fields from left to right, select Test type and Criteria from pick lists
- When possible use measured data
- When QSAR (log Kow) is used, consider the applicability to your substance, no BCF QSAR is considered as it is regarded as too optimistic by EU authorities
- Use of Qualitative Indicators for Bioaccumulation
o Check if the appropriate data like Mol weight, Molecular size, water and octanol solubility is inserted in the Substance worksheet
o At least two indictors need to be fulfilled to be acknowleged for the B Assessment
Log Kow (QSAR) > 10
Dmax > 43 A or Dmax > 17 A and MW > 1100 g/Mol / > 700 g/Mol
Log Coct/Cwater < 4
Coctanol < Critical Body Burden
Mammalian study with no or limited uptake (expert judgment)
- Measured data take precendence over QSAR over qualitative Indicators
- Overall B Assessment Result
o Not bioaccumulative (not B) or Bioaccumulative (B) or Very bioaccumulative (vB)
o Based on measured data / QSAR / qualtitative indicators for bioaccumlation
o ‘B Assessment‘ failed due to insufficient / conflicting data
Data input
TIP: QSAR input can be used for the quantitative as well as for the qualitative B Assessment (log Kow > 10).
Bioaccumulation Input Measured
Data
Bioaccumulation QSAR input
Bioaccumulation Qual. Indicators
mostly calculated from Subst. data
Assessment example with 3 different BCF
Example 1:
Example 2:
Example 3:
Overall B Assessment Result
Toxicity Assessment (T-Sheet)
General information
- The Section Ecotoxicity has data input possibilities for
- In Section Human Health Toxicity it needs to be considered
) – Fish, Daphnia, Algae
o If the substance is classified as R40 (Carc. Or Mutagen Cat. 3). R45, 46, 48, 60, 61, 62, 63, 64 this has to be indicated, select R phrase with highest toxic impact
- The Section Qualitative Indicators for Toxicity
o Is used either
When the substance is an EU listed Endocrine disrupter (EU COM (2001)262 final
When a octanol solubility is available which could be compared with the Critical Body Burden
Assessment Strategy
- Fill the pale yellow / orange input fields from left to right, select Test type and Criteria from pick lists
- When possible use measured data
- When QSAR (log Kow) is used, consider the applicability to your substance
- Human Health Toxicity – consider if the endpoint for which the R phrase is given has environmentally relevance (consult a Human Toxicologist)
- If the substance is a EU listed Endocirine Disrupter this can be documented here, currently this fact is not considered yet in the T Assessment but as an ALERT in the Result worksheet
- If the octanol solubility of the substance is below the Critical Body Burden for narcotic mode of action the substance is regarded as ‘not toxic‘. If Coct is higher than the CBB the result is assigned as ‘ambiguous’.
- Measured data take precendence over QSAR data or Critical Body Burden Approach. Human Health Toxicity overwrites ‘not toxic‘from Section Ecotoxicity – either quantitative or from QSARs.
- Overall B Assessment Result
o Not toxic or Toxic
Based on measured chronic ecotoxicity data / measured acute ecotoxicity data / chronic ecotoxicity QSAR / acute ecotoxicity QSAR / Critical Body Burden Approach
o ‘T Assessment‘ failed due to insufficient / conflicting data
Data input
Assessment Examples
Acute ecotoxicity
Ecotoxicity Input Measured Data
Ecotoxicity Input QSAR data / Read across
Human Health Tox
R Phrases
Qualitative indicators ED & CBB
Chronic ecotoxicity
Human Health Toxicity
Overall T Assessment Result
Result Sheet
Summary of the P, B and T Assessment
- In the Result worksheet the results of the P, B and T Assessments are listed together to give a total picture which allows to judge to a certain level the Uncertainty associated with the assessment
o If a P, B and T Assessment is soley based on QSARs / Read across the uncertainty might be relatively HIGH
o If a P, B and T Assessment is soley based on valid measured data the uncertainty might be relatively LOW
o The uncertainty associated with the assessment might trigger further testing to lower the uncertainty
- From the result of the single P, B and T Assessment an OVERALL Screening Result is derived
o Not PBT, not vPvB
o vPvB
o PBT
o PBT & vPvB Assessment failed
Recommendations
- Based on the Overall screening result the following recommendations are given
o Complete data in sections where assessment failed and / or contact CPS Tox
Summary of P, B and T Assessment + PBT Screening result
Hints on the Uncertainty of the Assessments
Recommendations
Verifying PBT Assessment
It is advisable to check whether the PBT Assessment is fully accomplished before printing out or exporting the result.
Double click Workflows > PBT
The PBT workflow window will indicate as below if the PBT Assessment has fully accomplished:
Retrieving from database
The retrieve function enables the users to search throughout the database for existing substance structure that can be assessed later for P-, B- and T assessment.
Double click Workflows > Retrieve to start:
Step 1: Login to the database
Fill up the information in the pop-up window after started retrieving to log in to the database.
By default, the following login information is used:
Username: guest
Password: guest
Database: ambit2
Step 2: Choose the searching type
Click to select from the list provided in the next pop-up window to define the search scope query, and then click Next >.
Step 3: Define the matching query
Choose from the drop-down menu under Field name, Condition and Value to define the matching query.
Step 4: Define the searching scope
Click to select the scope of the search from either Entire database, Last results, Previous search results or Datasets, and then click Next >.
Step 5: Insert search result for PBT assessment
Click to select from the search results to insert into the substance sheet for later P-, B- and T assessment.
Exporting PBT Assessment results
Saving PBT assessment result sheet
1. Double click Workflows > Export results;
2. Press <…> to choose the location where the result shall be saved;
3. Click to select file type to save as pdf, rtf, html or sdf;
4. Click Save;
5. Click Next.
Adding your PBT Assessment results into the Database
