The APVMA assessed residue data, toxicology information, food consumption patterns and dietary exposure estimates. Based on these assessments, the APVMA was satisfied that residues from the approved use of isocycloseram were within established health-based guidance values and did not present an unacceptable risk to consumers.
What is an MRL?
An MRL is the highest level of a chemical residue expected to remain in food when an agricultural chemical product is used according to approved directions. MRLs support food safety, compliance and trade, but they are not health or safety limits.
Consumer safety is assessed separately through dietary exposure assessments using health-based guidance values, including the acceptable daily intake for long-term exposure and the acute reference dose for short-term exposure. These values are based on toxicology studies and include safety factors designed to protect consumers, including vulnerable groups.
An increase in an MRL does not mean an equivalent increase in health risk. Numerical comparisons between MRL values, such as claims of a “500-fold increase”, do not show whether dietary exposure remains below the relevant health-based guidance values.
How the APVMA assesses food safety
Before an MRL is established, the APVMA assesses whether expected residues from the intended use meet Australia’s legislative requirements for consumer safety. This assessment considers how the product is used according to the approved directions and the likely exposure to consumers through food.
The APVMA works with Food Standards Australia New Zealand (FSANZ) to undertake dietary exposure evaluations. For isocycloseram, FSANZ independently verified the dietary exposure assessment.
The assessment found that long-term dietary exposure would be less than 20% of the acceptable daily intake and short-term exposure less than 10% of the acute reference dose.
On this basis, the APVMA and FSANZ were satisfied that the updated residue limits did not present an unacceptable risk to consumers.
Why MRL changes are made
The updated MRLs are associated with a permitted use pattern that allows application closer to harvest. This use pattern was requested to help growers protect crops from significant insect pest damage where there are limited control options close to harvest.
An MRL is only established where the APVMA is satisfied that expected residues from the intended use meet the relevant statutory criteria, including consumer safety.
What about PFAS
Some submissions raised concerns because isocycloseram falls within the Organisation for Economic Co-operation and Development (OECD) definition of a PFAS. PFAS definitions vary internationally and are generally based on chemical structure; however, classification under a structural definition does not, by itself, determine the regulatory risk of an individual chemical.
The APVMA’s decisions are determined by Australian legislation and informed by scientific expertise. In assessing applications, the APVMA considers more than chemical structure or whether a chemical contains fully fluorinated carbon atoms, including comprehensive chemistry data, toxicity, persistence, residues, exposure pathways and potential impacts on people, animals and the environment.
