For anyone registering a biological remedy in South Africa. This is information, not legal advice. Checked 26 October 2026.
The short version
Many biological remedies do not need residue field trials. The registrar's guideline expects a written rationale in the dossier either way. The rationale sets out the evidence on what the product is, how it works, its toxicity, exposure and fate in the environment. It shows why trials are needed or why they are not. Each type below has its own conditions, and a favourable example never overrides a condition that points the other way.
Why the registrar asks
Residue data is how the department checks that food is not put at risk after a crop is treated, and how maximum residue limits are set. The guideline calls biological remedies typically lower risk, but says some can still produce metabolites that are toxic, hazardous or allergenic. It also asks you to consider the co-formulants and carriers in the product, not only the active ingredient.
What you need to do
- Work out which type your remedy is: a virus, a bacterium or fungus (including inoculants), a macro-organism, a semiochemical such as a pheromone, a hormone, an enzyme, or an extract.
- Read the rule for that type below, and the guideline's own section for it. Check the exemption conditions and the conditions that require trials.
- Write your rationale. The guideline's annex gives a structure: show that the remedy poses no risk to people through toxicology, and none to the environment, using the evidence you have. That can be published literature, your own studies, analytical evidence or data on a similar product that you can justify. Use numbered references and add regulatory reviews from other countries where they exist.
- Put the rationale in the dossier, whether you are asking for an exemption or have run trials.
- If trials are needed, run them to the registrar's residue guideline. The registrar can also ask for further information.
What each type needs
Viruses must be highly specific to insects or to plant disease agents and must not cause human disease. For baculoviruses (insect viruses), no residue data is needed if the virus is properly identified and its mode of action is shown in the literature. Bacteriophages need the same for the phage and for the bacterium it is grown in, and that bacterium must not be known to produce metabolites of concern. If it is known to, the bacteria rules below apply.
Bacteria and fungi, including legume inoculants, have a list of seven cases where no trials are needed. Examples are that no harmful metabolites are known, genome analysis shows no gene for them, or the organism is on the European QPS list or the US GRAS list, or is registered as low risk in the EU. A second list gives cases where trials are required. It includes conflicting or unreliable evidence, a gene for a metabolite of concern, a close relation to a known mammalian pathogen, high or unacceptable consumer exposure, and a metabolite that is overproduced or concentrated in production. Read both lists.
Macro-organisms such as beneficial insects need no residue data when the life cycle shows nothing that could leave residues.
Semiochemicals such as pheromones need no residue data if the product or device does not touch plant parts and leaves no residue, as with a trap or dispenser. Other routes exist where the product touches only non-edible plant parts and is not systemic, or where the Department of Health grants an exemption. If it touches edible parts and there is a toxicological concern, data is needed.
Plant hormones usually need no residue studies, but you must ask for an exemption from a maximum residue limit and give a reasoned scientific argument. This is decided case by case. Hormones from insects or other non-plant sources follow a separate route that depends on the toxicity profile and how the product is applied. Synthetic growth regulators are not covered by this guideline.
Enzymes need no residue analysis only if they come from non-pathogenic, non-toxin-producing micro-organisms grown on raw materials without hazardous components, and the dossier proves it. Toxins are not treated as enzymes. If the conditions are not met, residue data is needed.
Extracts with documented use in human food or animal feed at similar concentrations usually need no residue studies. You must show the extract is the same as the one supplied to the food or feed industry and meets food legislation. Known allergens need an exposure assessment. Above documented use, you need a scientific rationale or bridging argument. Extracts with no comprehensive history of use, or used well above normal exposure, fall under the conventional chemical data requirements, with options for scientifically justified deviations. The guideline also lists exemption cases and trial triggers for extracts.
Two cautions
For bacteria and fungi, the evidence has to be about your strain. One strain that makes no harmful metabolite does not show the same for every strain of the species, unless you can show the strains are genetically equivalent.
An exemption accepted in South Africa does not settle the rules of the country you export to. Check the importing market's limits with the importer or agent.
Check with the registrar
The guideline says a rationale should be submitted in all cases for bacteria and fungi, and points to its annex for all biological products. It also says exemption requests for plant hormones are decided case by case. If you are unsure how this applies to your product, ask.
The macrobial guideline says no residue data are needed. This guideline keeps an exception where residues are suspected, so do not assume a macro-organism product is exempt.
If your product sits between two types, ask before you build the dossier. The guideline gives no time frame or fee for the residue assessment.
Source
Guidelines on requirements for residues arising from the use of biological remedies in South Africa, issued by the Registrar of Act 36 of 1947, July 2026. Published on the department's guidelines page: https://www.nda.gov.za/index.php/publication/581-guidelines