MRLs

What are MRLs

The Australian Pesticides and Veterinary Medicines Authority (APVMA) sets maximum residue limits (MRLs) for agricultural and veterinary chemicals registered for use in Australia.

For practical purposes there are three standards used in Australia and overseas countries relating to chemical residues:

Maximum residue limits (MRLs)

The APVMA defines an MRL as “the maximum concentration of a residue resulting from the registered use of an agricultural or veterinary chemical which is legally permitted or recognised as acceptable to be present in or on a food, agricultural commodity or animal feed”.

These MRLs are set at levels that pose no risk to human health and are not likely to be exceeded if used in accordance with label directions for each product. Hence MRLs are generally not considered to be related to any food safety issues. MRLs are therefore related to control of use of a chemical.

MRLs may be set for:

Food for human consumption
Stockfeed
MRLs for human consumption may also apply to stockfeed
Regulations may be silent in an area of the above

Extraneous residue limits (ERLs)

ERLs relate to residues originating from environmental sources of pesticides that are no longer registered (e.g., organochlorines).

Maximum levels (MLs)

MLs for particular contaminants are established for foods which provide a significant contribution to the dietary exposure. MLs are set at levels that are consistent with the protection of public health and safety, and are reasonably achievable through sound production and natural resource management practice. They generally relate to heavy metals and mycotoxins and are not considered further in this section.

For a brief definition and description of a range of terms related to chemicals, click here

How MRLs are Set

Each country has its own chemical regulations and method for setting MRLs (see Chemical Regulations). A range of factors are taken into account, including different climates, pests and diseases and approaches to risks and food safety in general.

Many countries either follow international guidelines (i.e., based on WHO/FAO/OECD) or their own.

In general the process involves one or more (may be other factors also):

Critical Gap (label directions such as rates of application, commodity, pest, withholding period etc.) to ensure efficacy
Safety (for consumers) via a dietary exposure assessment
WH&S, environmental impacts
Residue definition (main compound and any breakdown metabolites)
Evaluation methods
Use of an MRL calculator, to ensure MRL is “defendable”
For countries such as Australia, the potential risk to trade of residues being present is also taken into account

For information on how MRLs are set by the CCPR technical body JMPR, click here

For information on how the APVMA performs a residues and trade risk assessment click here

Consultation on Setting MRLs

The APVMA (and FSANZ, most overseas countries) consult with governments and the general public on recommendations for MRLs (and a range of other chemical related matters). On behalf of the grains industry, through a GRDC project, the Chair NWPGP monitors those “calls for submissions” in Australia and overseas and provides feedback based on the implications for the Australian grain industry.

Where required, advice on impending changes will be provided to industry seeking industry comments on the implications of those changes and market access risks to industry should those changes be implemented. This is done via an “NWPGP Chemical industry distribution list” – to be added to that list, email here

For information on how various regulators and the NWPGP consults with industry on a range of these matters, click here

Interpreting MRLs

Given differing MRLs in each country, it is important to correctly interpret the MRL Standards in order to ensure residues on consignments meet their requirements. When considering the MRL that may apply to a particular chemical / commodity, the following need to be review:

Whether a country is specific in all respects of their MRL legislation as listed in this section or whether it is silent in one or more aspects.
Whether the country has its own legislation, lacks legislation or defers to another country/international standard such as Codex.
Whether changes to MRLs are pending or underway and the date those changes will apply.
If the MRL applies to the specific commodity and is therefore explicitly listed (i.e., wheat) or whether a crop Group MRL exists (e.g., Cereal Grains).
If no MRL exists, whether a low level tolerance (default MRL) applies or zero applies. If zero applies, any residue detection may be a contravention of regulations.
Sampling and testing methods that are used to assess residues in imports, with technology able to detect very low levels of residues meaning that “zero” may not be practically achievable. In many instances there are no internationally agreed sampling and testing methods. Methods may also vary for bulk versus container consignments.

Import Tolerances

FSANZ has an Import Tolerance (IT) process to allow for trade into Australia where an MRL for a particular chemical/commodity combination does not apply. It does this by:

Considering requests to harmonize Australian MRLs with MRLs established by Codex Alimentarius or other countries where the commodity is produced.
A range of data is required to be provided and then assessed by FSANZ, including dietary exposure and intake assessments.
If accepted, the MRL will be adopted in Schedule 20 of the Food Standards Code.

Countries may or may not have an IT process, with variations in the requirements for those that do operate an IT process (e.g., data requirements, application fees). Without an IT process, if a country does not have a specific MRL, Australia may not be able to seek an MRL and thus place at risk useful chemical tools for growers or face increased risks of market access violations if grain is exported to that country.

FSANZ has been instrumental in developing an “APEC Import MRL Guideline” in an attempt to encourage countries to adopt a common approach when setting IT regulations.

For information on the APEC Import Tolerance Guidelines, click here

Export Market MRLs & Databases

As noted there are a range of regulations related to chemical regulations that apply in individual countries. When considering the information available, refer also to the section on “Interpreting MRLs”.

As regulations change over time, including MRLs, details of legislation and MRLs are not included here. For updated information, industry may either:

Seek specific information from the Chair NWPGP; or
Search individual country regulations on-line, noting some may be in non-English language and some may not be readily available; or
Search a list of countries from sources available on-line, either free or subscription based. Examples are in the table below

General Country MRL Sources

Source	Reference
Codex	http://www.fao.org/fao-who-codexalimentarius/codex-texts/dbs/pestres/pesticides/en/
Most countries	https://www.bryantchristie.com/ (subscription based)
Various countries	https://www.mpi.govt.nz/growing-and-harvesting/plant-products/pesticide-maximum-residue-levels-mrls-for-plant-based-foods/pesticide-maximum-residue-level-legislation-around-the-world/
Various countries	https://www.agriculture.gov.au/ag-farm-food/food/nrs/databases

For a guide to trends in markets, further information to consider when determining an MRL that applies in a country, refer to here

Challenges with MRL Setting for Industry

There are various challenges when trading grain internationally due to the different approaches to setting MRLs. Different approaches to setting MRLs may mean a different MRL is set:

MRL in importing country is higher than the Australian MRL.
The fate of residues from the point of application and the relationship with resulting residues on the final commodity exported is relatively unknown given a range of variables such as:
- Different conditions when chemicals are applied
- The label rate used
- Not all areas (i.e., of a paddock) may have had the chemical applied
- Not all growers may have used a registered chemical
- Segregation of treated versus untreated grain
- Bulking and blending with grain that was not treated during the supply chain prior to export.
Disharmonised MRLs refers to MRLs that differ in each country because of the method/approach to setting MRLs. For example some countries may take a hazard approach to setting MRLs while other take a risk based approach.
Missing MRLs refers to MRLs that exist in an exporting country but do not exist in the importing country for that specific chemical / commodity.
Lack of an Import Tolerance setting policy.
Support for old compounds. Different countries have differing approaches to re-evaluation of previously registered compounds. The resources (data generation, cost etc.) required to support reviews of compounds is often outweighed by the commercial returns of sales of that compound. Hence many old compounds may not be supported.
MRL setting policies are increasingly being influenced by public concerns and views on chemical use/residues generally in food, water and the environment.

All of the above may lead to a change in risk profile of grain to a particular market. Many factors are common to all major grain exporters, hence industry organisations such as Grain Trade Australia are involved in advocacy efforts with other industry organisations worldwide to communicate the impacts of different regulatory regimes (e.g., missing MRLs) on regulators.

For a comprehensive review of many of these issues, please refer to the United States International Trade Commission Report (Executive Summary) here.

Industry Management of Market Requirements

The main activities of the chair NWPGP, under a contract with GRDC are:

To monitor changing market regulations and MRLs, review their impact on the industry and consider with Government any response required to the importing country seeking a review of their proposed changes.
Review any changing Australian regulations and co-ordinate a response on behalf of the NWPGP.
Provide general advice on market regulations and MRLs to industry on request.
Attend CCPR meetings and represent the interests of the Australian grain industry.
Organise the annual NWPGP conference.

The above information enables industry to be informed of risks of exporting grain to countries in relation to chemical residues. In general, before supplying grain to a market, industry needs to:

Understand the registration status of each chemical in Australia.
Understand the MRL is Australia and the overseas market.
Consider any residues arising from the use of each chemical.
Review management strategies along the supply chain that may impact on the level of residues on grain and thus mitigate and potential market access risks.
Finally, determine the risk of impacting market access if grain were to be shipped.

The management strategies used vary depending on a range of factors but can include:

Requiring growers to comply with the On-Farm Stewardship Guide, showing compliance with good management practices regarding chemical use.
Requiring growers to provide advice on chemical use through a Commodity Vendor Declaration (CVD).
Segregate grain on receival into storage.
Sample and test grain to select stock with required residue levels.
Only outturn grain once residue levels are known.
Only trade grain domestically or export grain that meets market requirements, as per requirements of industry documents such as the Grain Trade Australia “Code of Practice for the management of grain along the supply chain”.
Sample and test grain once supplied through their own QA program and/or participation in the National Residue survey, to confirm the residue status of the grain and that all management strategies used were appropriate.

For a copy of the Onfarm Stewardship Guide, click here

For a copy of the Australian Grain Industry Code of Practice, including relevant Technical Guideline Documents (e.g., TGD No.6 Grain Certification, TGD No.14 A Guide to CVDs, TGD No.15 Managing Chemical Violations), click here

For a copy of various Commodity Vendor Declarations (CVDs), click here

For further information on industry obligations relating to meeting market requirements, click here