Speciality Chemicals Magazine NOV / DEC 2022 | Page 24

BIOCIDES

Product PT Use Human Exposure

Additional human exposure steps

Environmental exposure

Product 1 ( hand soap ) 1 # 1 Dermal - STP Product 2 ( trigger spray ) 2 # 4 Dermal and inhalation ( RTU ) - STP Product 3 ( liquid to be vapourised ) 2 # 17 Dermal and inhalation Fine particles STP

Product 4 ( liquid to be diluted ) 4 # 30 Dermal ( to be diluted )

Table 1 – Risk assessment of different products Note – For product 1 , the new guidance document lists the different uses in a table at pages 29-31

Mixing and loading + dietary risk assessment

STP

The matrix shows cells with different colours : red means that the use is not acceptable , green that it is acceptable and yellow that the approach should be discussed with the evaluating competent authority ( eCA ), with robust justification for the reasons of this grouping . The eCA can agree or disagree with the applicant ’ s justification and may ask for a family modification . A maximum of two red cells should be allowed per family . As seen in Figure 2 , it is likely to have a positive feedback on the yellow cells , but the vapourised product needs to be removed from the family because its presence leads to three different red cells . Condition 4 defines the similarity of the level of efficacy . It is very difficult to provide a clear indication on what is considered similar from the efficacy point of view , so the authorities decided to leave this decision in the hands of the applicants . The limitation is that the minimum level of efficacy , over the whole potential range of products within the BPF , should be taken into consideration for authorisation . In this case , the applicant should identify a ‘ worst case composition ’ and prove its efficacy . This term means :

• Lowest ( in use ) concentration of active substance ( this term refers also to a product that needs to be diluted before the application )

• Lowest ( in use ) concentration of coformulants positively affecting efficacy

• Highest ( in use ) concentration of coformulants negatively affecting efficacy

• The physical-chemical property ( e . g . pH value ) most unfavourable for efficacy In cases where the minimum concentration of active substance or associated co-formulant compositions do not support the majority of the label claims within the family ( the so-called core ), the applicant can apply for a sub-set of the core and justify the reasons for this request . For example , in the afore mentioned BKC family the amount of active ingredient necessary for hand disinfection is smaller than the amount necessary for surface disinfection and it will never be sufficient to support the latter claim . Sub-sets are possible but they need to be decided on a case-by-case approach , also taking into account condition 5 ( similarity of level of risk ). In principle , all products within a BPF should be similar enough to be covered by the same risk assessment relative to human health and another one relative to the environment . However , if it is not possible to describe all products with the same set of information correctly ( especially in terms of classification and labelling , formulation types ), it is possible to divide the products within the BPF into subgroups ( meta-SPCs ). One of the purposes of the meta- SPCs is to enable the notification of new products subsequent to the family approval without a renewed testing or evaluation effort . Thus , when notifying a new product , the assignment to a meta-SPC and thus the correct classification and labelling , as well as indication of risk mitigation measures , are possible without re-evaluation . With regard to the example of the family above , there are differences in the risk assessment referring to the different products ( Table 1 ). Environmental risk assessment ( ERA ) is not complex , since the exposure of the products is all via sewage treatment plants , and the in-use concentrations for the surface products would be similar and higher than that of the hand soap . In this case it would be possible to cover all the family with the same ERA . On the other hand , human health risk assessment is different for the different products and it would be rather unlikely that this could cover the whole family .

Conclusions

BPFs are powerful tools that companies can use to group similar products under the same authorisation procedure . Products containing quats are eligible for this procedure since many of those present on the market are rather ‘ similar ’ to one another . The authorisation procedure is fairly complicated and it is advisable to seek the help of an expert . It is also crucial to concentrate the efforts on the products that constitute your main business , and to try to keep the family simple or submit several families in order to avoid rejections from the eCA . •

Dr Daniela Romano

REGULATORY AFFAIR MANAGER – BIOCIDES

24 SPECIALITY CHEMICALS MAGAZINE ESTABLISHED 1981