Following the manufacture of a pesticide technical material (active ingredient, a.i., active substance a.s.) the manufacturer must prepare a formulation to ensure that it can be used in a safe and efficacious manner. In order to do this the technical material is mixed with other ingredients (sometimes called inert ingredients and or co-formulants) to improve its effectiveness, safety, handling and storage. The other ingredients can include solvents, mineral clays, stickers, wetting agents or other adjuvants^1,2.

Pesticide formulations may contain one or more active ingredients and come in many different variations depending on the nature of the active ingredient and the proposed use. Formulations may be in the form of solids (e.g. dustable powders), liquids (e.g. emulsifiable concentrates) or gases (e.g. fumigants).  Formulations of different active ingredients can in some cases be mixed before use, however, this should only be done if it is known that the two formulations are compatible and that there will be no adverse effects due to the mixing of the formulations.

Pesticide formulations may also come ready to use or require dilution before use. In some cases spray adjuvants can be added to the diluted formulation in order to enhance the performance of the pesticide. Adjuvants are usually classified according to their use rather than their chemistry, they include surfactants, crop oils, antifoaming agents, stickers and spreaders³. Care must be taken when adding adjuvants to a given formulation to ensure that there are no compatibility problems which could make the pesticide less effective.

There is an international coding system for the different pesticide types. The codes, together with definitions, are given in the “Catalogue of Pesticide Formulation Types and International Coding System” published by CropLife International ⁴.

Some examples of the coding system are:

Water Dispersible Granules (Code WG) – a formulation consisting of granules to be applied after disintegration and dispersion in water.

Emulsifiable Concentrate (Code EC) – a liquid, homogeneous formulation to be applied as an emulsion after dilution in water.

Vapour Releasing Product (Code VP) – a formulation containing one or more volatile active ingredients, the vapours of which are released in the air.

References

1. Pesticide Formulations – National Pesticide Telecommunications Network (December 1999)

      http://npic.orst.edu/factsheets/formulations.pdf

2. Pesticide Education Resources, University of Nebraska, Lincoln, Unit 3 – Formulations

      http://pested.unl.edu/pat3.htm

3. B.J. Brecke and J.B. Unruh, University of Florida, IFAS Extension – Spray Additives and Pesticide Formulations (Fact Sheet ENH-82), February 2003

      http://edis.ifas.ufl.edu/pdffiles/LH/LH06100.pdf

4. Catalogue of Pesticide Formulation types and International Coding System, Croplife Technical Monograph No. 2, 6^th Edition, May 2008

      http://www.croplife.org/files/documentspublished/1/en-us/PUB-TM/4147_PUB-      TM_2008_05_01_Technical_Monograph_2_-_Revised_May_2008.pdf

Last modified 7^th April 2010