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The Applicant Guide: Adjuvants

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Adjuvants are authorised under European legislation Regulation (EC) No 1107/2009, which came into force on 14 June 2011.

Definition of an 'Adjuvant'

Under Article 2 Scope (3d) of 1107/2009 an adjuvant is defined as:

‘substances or preparations which consist of co-formulants or preparations containing one or more co-formulants, in the form in which they are supplied to the user and placed on the market to be mixed by the user with a plant protection product and which enhance its effectiveness or other pesticidal properties, referred to as ‘adjuvants’.

Products of the following types are considered by HSE to fall within this definition of an adjuvant:

HSE does not currently regulate other types of spray additives, such as dyes, markers, carriers, anti-transpirants or anti-foaming agents.

The Official List and the List Entry

A company wishing to market an adjuvant for use with a plant protection product in the UK must apply for its inclusion on the 'Official List of Adjuvants'.

The 'Official List' provides details of the adjuvant products that may be used with plant protection products and the conditions of use to which they are subject.

Each Officially Listed adjuvant product is issued an individual 'List Entry' which specifies the identity of the adjuvant and the conditions that a user will need to comply with. At any point in time there will be only one extant List Entry for each adjuvant product.

The Official List is published in full on the HSE website adjuvant database, any additions and amendments are updated regularly on the website (link to Adjuvant database on HSE Website).

More information on adjuvant list entries

What are the controls on adjuvants?

Our legal controls on adjuvants are limited to controlling the use of adjuvants with plant protection products.

Unlike with plant protection products, we do not have controls on advertisement, sale, supply or storage of adjuvants, although other legislation will apply in these areas.

More information on the legislative controls over adjuvants

How do I include an adjuvant on the Official List?

 You must submit an application (see further information in guidance document) containing information demonstrating the safety of the adjuvant for the proposed uses.

What is an Effective Adjuvant Component?

An Effective Adjuvant Component (EAC) is the main active component of an adjuvant.

What data requirements do I need to address for the inclusion of my adjuvant on the Official List?

You must provide appropriate data or information on:

Where an EAC has been previously considered in an Officially Listed adjuvant and where you have access to the data used to support that Official Listing, you may be able to reference the previously submitted data rather than submit new data (see below). You will need to ensure that you explain why the data you are referencing are relevant to your application.

How may I address the data requirements?

You may address the data requirements by:

All studies must be:

What should I include in an application for the inclusion of an adjuvant on the Official List?

See Guidance document on what to include in an adjuvant application.

Do I need to submit a draft label

We have no legal control over the marketing and advertisement of adjuvant products. It is your responsibility to ensure that any product literature is in accordance with both the conditions of use of the adjuvant as specified in the List Entry and the pesticide authorisation. A product can be removed from the Official List if the marketed label or other literature does not comply with conditions in the List Entry or the relevant plant protection product authorisation(s).

Guidance on the labelling of pesticide products is given in The Labelling Handbook. You may wish to use this guidance to help you produce a draft label for your adjuvant product.

What about Classification, labelling and Packaging (CLP) Regulation (EC 1272/2008)?

Adjuvants are subject to the Regulation on Classification, Labelling and Packaging (CLP) of Substances and Mixtures (EC) No. 1272/2008. Advice on labelling with regard to CLP is available on the HSE's website. You should provide details of proposed classification and labelling when you submit your application.

How will my application be processed?

General information on where to submit applications, processing times and information set out during evaluations is in the Applicant Guide.

What stream will my application be placed into?

Adjuvant applications are placed in our usual processing streams (see the guidance document on application streams for further information).

Applications for an adjuvant product with a new EAC which has not previously been included on the Official List will usually be considered via the zonal lead (52 week) stream, as will applications for a new source of EAC, or ones with supporting residues data.

Some applications require no technical input, and can be considered via the Admin stream.

How much will my application cost?

Adjuvant applications are free of charge.

What happens after my application is completed?

If your application is successful, we will inform you in the normal way (see The Applicant Guide for further information).

An electronic copy of the List Entry will be included on the Adjuvant Database and  new products will be added to the Official List of adjuvants. For any changes to existing products, the List Entries will be amended appropriately.

If your application involved a major change to the product's identity, we will produce a List Entry for both the 'new' product and the 'old' product. There will normally be aa use-up period for 'old' products.

If your application is unsuccessful we will explain the reasons why your application has been refused and specifying what data requirements you need to address if you wish to make a further attempt to obtain inclusion on the Official List of Adjuvants of a product or new use of an existing product. You can obtain a copy of the full Official List from us- see Contact Details page, or you can consult the Adjuvants Database on this website for information on those in the List.

Unique registration (ADJ) number

Upon issue of the first Official List Entry for your adjuvant product, your adjuvant will be assigned a unique adjuvant registration number, prefixed by 'ADJ'. The number allocated will always remain with your adjuvant product, unless you subsequently make a major change to its identity or to its formulation.

See the guidance document on registration numbers for details of when we may need to issue or change an 'ADJ' number.

What happens after a List Entry has been included on the Official List of Adjuvants?

We carry out regular checks to ensure that List Entries are up-to-date.

If revocation action is taken against a pesticide or its uses which will affect your List Entry,  we will amend your Entry.

What if I want to take my listed product or use off the market?

If you wish to withdraw a product or use for the the Official List, please follow the guidance on commercial withdrawals.

Further information


Updated 2019-11-28