PBT & PMT screening tool

The basic approach is to score chemicals from 0 (no or very low PBT/PMT potential) to 1 (very high PBT/PMT potential). Apart from the overall PBT/vPvB and PMT/vPvM-scores, for the individual properties P, B, M, and T the scores are constructed to give:

• a score of 0 to 0.33 to indicate low to moderate P, B, M and/or T potential;
• a score of 0.33 to 0.5 indicates high P, B, M and/or T potential;
• and a score of 0.5 to 1 indicates very high P (vP), B, (vB), M (vM) and/or T potential.

The P-score for PMT screening is different from the P-score for the PBT screening. This is because the PBT assessment aims at substances that accumulate in soil and sediment (strongly adsorbing hydrophobic substances). The PMT assessment aims primarily at substances that tend to stay in water (hydrophilic mobile substances).

In soil and sediment the half-life is longer than in surface water. Therefore, different criteria are used for soil and sediment compare to water. Because hydrophobic substances accumulate in soil and sediment, the overall persistence of this substances mainly depents on persistence in soil and sediment. Therefore, the overall persistence for PBT/vPvB estimation is based on criteria for soil and sediment. As a result for the same substance different P scores can occur in the screening for PBT and PMT properties. Because hydrophilic substances do not bind to soil and sediment comparing to the overall persistence with the criteria for soil and sediment is not relevant. In soil and sediment the half-life is longer than in surface water. Therefore, different criteria are used for soil and sediment compare to water. Because hydrophobic substances accumulate in soil and sediment, the overall persistence of this substances mainly depents on persistence in soil and sediment. Therefore, the overall persistence for PBT/vPvB estimation is based on criteria for soil and sediment. As a result for the same substance different P scores can occur in the screening for PBT and PMT properties. Because hydrophilic substances do not bind to soil and sediment comparing to the overall persistence with the criteria for soil and sediment is not relevant.

The overall PBT/vPvB and PMT/vPvM scores are constructed based on the scores of three the individual indicators.

The overall PBT/vPvB and PMT/vPvM scores are constructed based on the scores of three the individual indicators.

The most recent paper describing the methodology in detail is available via this link. The methodology is based on earlier work by Rorije et al. (2011) and Hartmann et al. (2021). A more practical description of the methodology as well as its application domain and interpretation of its output can be found on the PBT/vPvB information page and the PMT/vPvM information page.

Input

A CAS number of a chemical structure needs to be provided as input. The user can either search a single substance using the tab ‘Search single substance’ or a list of substances (CAS numbers) using the tab ‘Search a batch of substances’. Not all CAS numbers are included.

Output

The output for a single substance search includes the CAS-number and (when available) the name of the input chemical as well as the overall combined PBT, vPvB, PMT and vPvB scores and the individual P, B, M and T scores for that substance. Furthermore, an explanation of the scores is provided, which includes the predicted indicators for P, B and M that are used for the calculation of the scores. A link to more detailed substance information is also given, if available.

The output for the batch search includes the same information as the single substance search, except for the explanation on the P, B and M scores. A link to get that information per substance is included.

Proclaimer

The results of the PBT & PMT screening tool provide a prediction of potential PBT/vPvB or PMT/vPvM properties. It should be noted that a low or high score is only a first indication that the substance is of potential low or high concern (for having PBT/vPvB or PMT/vPvM properties). A low score does not necessarily mean that there is no PBT/vPvB or PMT/vPvM concern. Conversely, a high score does not necessarily mean that a PBT/vPvB or PMT/vPvM criteria are fulfilled. The screening approach should be used as a first screening step, which needs to be followed by further investigation of these properties. For this, expert judgement is needed. Follow-up can for instance include collection of emission data and/or experimental data on persistence, bioaccumulation, mobility and/or toxicity. When evaluating the presented output, it is advised to not only look at the smiley indicators but to pay attention to the underlying scores.

New knowledge or insights can lead to changes and updates of the tool. Changes to a new version will be published on this website.

Finally, it should be noted that predictions of low PBT ot PMT concern (or absence of any prediction) does not mean that a chemical can be used safely. Other effects or properties might not be excluded. Substances might still be of potential concern for human health and/or the environment, for instance because of Carcinogenic, Mutagenic and/or Reprotoxic (CMR) properties. It should be noted that a low or high score is only a first indication that the substance is of potential low or high concern (for having PBT/vPvB or PMT/vPvM properties). The screening approach should be seen as a first screening step, which can be followed by further investigation of these properties. When evaluating the presented output, it is advised to not only look at the smiley indicators but to pay attention to the underlying scores.

Finally, it should be noted that predictions of low PMT concern (or absence of any prediction) does not mean that a chemical has no PBT or PMT concern per definition. The other way around, the prediction of a high PBT or PMT concern does not per definition mean that the substance has a high concern. The predictions are base on a model approach.

For more information please read the PMT/vPvM information page, PBT/vPvB information page, CMR information page or ZZS information page (in Dutch). Further more other effects or properties might not be excluded. Furthermore, substances might still be of potential concern for human health and/or the environment for instance because of Carcinogenic, Mutagenic and/or Reprotoxic (CMR) properties. For more information please read the PMT/vPvM information page, PBT/vPvB information page, CMR information page or ZZS information page (in Dutch).

Abbreviations

CMR

Carcinogenic, mutagenic or reprotoxic

M

Mobile

PBT

Persistent, bioaccumulative and toxic

PMT

Persistent, mobile and toxic

vPvB

Very persistent and very bioaccumulative

vPvM

Very persistent and very mobile

ZZS

Dutch Substances of Very High Concern (in Dutch: Zeer Zorgwekkende Stoffen)