RIVM has developed a method to assess the extent to which mixtures of Substances of Very High Concern (SVHCs; in Dutch ZZS) harm the environment. Environmental services and other permit issuers can use the method and the maps to determine whether they should issue a permit. RIVM recommends further developing these methods together with permit issuers in practice. This study is a follow-up to an exploratory study from 2022.

Mixtures of SVHCs require more attention

The government issues permits to companies specifying the quantity of chemical substances, including SVHCs, that they are allowed to emit into the air and water. These are often mixtures that contain several different substances at the same time. The permit issuer only looks at the safety of each individual substance, rather than that of the entire mixture. The harmful effects of a mixture could be greater than the effects of a single substance. The level of this risk depends on the mixture’s composition, the concentrations of the individual substances and the hazard posed by them.  

Method for assessment by a permit issuer 

RIVM has developed a method to determine the estimated risks of substance mixtures in the living environment. This method will help permit issuers, such as environmental services, to complete the assessment and consists of two steps. 
The first step involves looking at whether the combined risks for the individual substances exceed a cut-off value. If this is not the case, that means the relevant mixture will have a limited risk. If the combined risks do exceed the cut-off  value, the specific toxicity of these substances must be considered.  
It is important that the described method should also be effective in practice. That is why RIVM submitted the method to representatives from implementing organisations during a workshop of the SVHCs knowledge network. RIVM recommends further developing the method together with permit issuers and putting it into use. 

Maps that show where SVHCs are most prevalent

The RIVM report contains several maps that show where the effects of industrial emissions of SVHCs on humans and the environment are most significant in the Netherlands. There is currently still a lack of data. RIVM is developing a database with information on the emission of SVHCs by companies. This information should help increase the accuracy of the maps.  
Together with implementing organisations, RIVM will investigate how these maps can be used in practice, including in connection with the new Environment and Planning Act in the Netherlands. 

Ambition for 2050 

RIVM emphasises the importance of reducing the emission of SVHCs by companies as much as possible. This will reduce the risk that mixtures of SVHCs will have harmful effects on people and the environment. The Netherlands strives to make the risks from SVHCs in the living environment negligible by 2050.

Collaborating with environmental services 

RIVM is collaborating with Omgevingsdienst NL (the association for the 28 environmental services) to create a national structure for sharing knowledge and advice about SVCHs. This collaborative structure could be expanded to include other themes and organisations. 

RIVM research into SVHCs 

RIVM is carrying out extensive research into SVHCs. Today, RIVM is also publishing an exploratory study into SVHCs in the energy transition. For example, different SVHCs are used in wind turbines, solar panels and batteries.   
To minimise the emission of SVHCs, companies must draw up an action plan with concrete measures. This is referred to as an avoidance and reduction programme (ARP). An exploratory study by RIVM has shown that there is a need for criteria for drawing up and assessing an ARP,  both among companies and among permit issuers.  
This report is a follow-up to a previously published study.  
Limited consideration of combination effects of hazardous substances when granting SVHC permits | RIVM