Australian agvet chemical review program in perspective

Take home messages

• The Australian agvet regulatory system is a scientific, evidence-based risk assessment process which is highly recognised internationally.
• Agvet chemicals are nominated for review based on key criteria of concern including human health (toxicology and occupational health and safety), environment, residues and trade, target crop safety and efficacy.
• The greatest direct influence that grain growers can have on retaining their access to agvet chemicals is to only use chemicals for their registered or permitted use and closely adhering to all label directions for use.
• Maintenance of access to agricultural chemicals for broadacre use is reliant on growers showing strong stewardship in following label directions for use.

Background

The Australian Pesticides and Veterinary Medicines Authority (APVMA) is the Australian Government regulator of agricultural and veterinary (agvet) chemical products. It is responsiblefor the regulation of agvet chemicals into the Australian market place and needs to be satisfied that the intended use does not harm the health and safety of people, animals and crops, the environment, and trade. It does this through:

• Evidence-based evaluation and approval of active constituents and the registration of agvet chemical products.
• The review of certain agvet chemicals of concern to ensure that they continue to meet contemporary scientific standards.

For an agvet chemical product to legally be manufactured, imported, supplied or sold in Australia, it must be registered by the APVMA. The registration process involves scientifically evaluating the safety and efficacy (effectiveness) of a product in order to protect the health and safety of people, animals, plants and the environment.

The APVMA looks to new data, information and science when considering the ongoing safety of a registered product, the full range of risks and how human exposure can be minimised through instructions for use and safety directions.

The assessment determines whether the agvet product, when used in accordance with the label or permit directions for use, would have a harmful effect on human health, occupational health and safety, the environment or trade.

The APVMA’s approach to chemical risk assessment

All products registered for use in Australia have been through a robust chemical risk assessment process and are safe when used as per the label instructions.

As Australia’s agvet chemical regulator, it is the role of the APVMA to consider all relevant scientific material when determining the likely impacts on human health and worker safety including long term and short-term exposure to users and residues in food before registering a product.

It is the role of the regulator to determine whether products used according to label instructions could result in a level of exposure that poses an unacceptable risk.

Consistent with regulators in other countries, the APVMA uses a risk-based, weight-of-evidence assessment, which considers the full range of risks, including studies of cancer risks, and how human exposure can be minimised through instructions for use and safety directions.

Chemical risk assessment = hazard assessment + exposure assessment

Hazard assessment: an assessment of the data related to the intrinsic toxicity potential of an active constituent and/or formulated product.

Exposure: an assessment of the likely exposure of humans and environmental organisms that takes into account how the chemical product is to be used, the type and formulation of the product, and the crops or animals to be treated.

Australian Chemical Review Program

The APVMA considers a wide range of scientific data submitted by registrants in support of an application to approve an active constituent or to register a product containing that active constituent.The Chemical Review Program reconsiders the registration of agvet chemicals in cases wherecredible new scientific information has been generated after a product has been registered that suggests the existence of previously unknown risksto human health, worker safety, the environment, trade and/or product performance has been identified.

If this happens, the APVMA can initiate a reconsideration process (commonly called a chemical review) to assess the identified risk(s) and determine whether changes are needed to ensure that the product can continue to be used safely and effectively.

Chemical reconsiderations are managed under the auspices of the APVMA’s Chemical Review Program, which was established in 1995.

The APVMA may undertake a reconsideration to scientifically reassess the risks and determine whether regulatory changes are necessary.Depending on the review’s findings, active constituents and the products containing them might:

• be confirmed as safe and appropriate for the registered use(s).
• be restricted in use, by making label amendments to limit the situations in which product(s) may be used, or;
• have its registration suspended pending specific action or cancelled or be withdrawn voluntarily from the market by the registrant(s).

The reconsideration process incorporates legislative, administrative and scientific elements that contribute to the final decision to affirm, vary, suspend or cancel a registration. As a result, reconsiderations can be complex, have high resource requirements and long timeframes.

Prior to 2014, chemical reconsiderations were not time limited—the timeframe of individual reviews was determined by the scope and specific details of the review. For this reason, the time that it has taken to complete individual reviews has been highly variable, ranging from less than six months for the most straightforward label review to more than 10 years for some of the more technically complex and large reviews. The average time taken to complete a review has been just over three years.

From 1 July 2014, chemical reviews will be completed within a prescribed timeframe — under current legislation, a reconsideration must be completed within a maximum of 57 months.

Listing of agricultural chemical reviews

Over the more than 20 years that the Chemical Review Program has been in place, a total of 63 reviews have been completed, with 13 chemicals currently under active review. An additional 19 chemicals have been identified for review prioritisation (Table 1).

Of the 13 chemicals currently under review, eight have broadacre grains registrations as highlighted in Table 1.

Of the 63 completed chemical reviews, 10 had broadacre grains registrations and are listed in Table 2 with a brief description of the regulatory decisions which resulted in:

• Registrations cancelled of two products (endosulfan and fenthion).
• Label amendments/variations of four products (atrazine, dimethoate, diuron,omethoate).
• No changes to broadacre cropping use patterns of four products (bifenthrin, bromoxynil, carbendazim, glyphosate).

A full description of the review status details and regulatory decision(s) for all current and completed chemical reviews is available on the APVMA website.

Listing of chemical reviews is available here.

Prioritisation of chemicals nominated for review

Agvet chemicals nominated for review by the APVMA are given an order of priority according to the level of concern that led to the nomination.

The APVMA and its external advisory agencies use a scoring process to prioritise nominated chemicals for review, based on key criteria of concern including human health (toxicology and occupational health and safety), environment, residues and trade, target crop safety and efficacy. The priority for each chemical nomination is determined by assessing it against each of the criteria and evaluating the outcomes.

Human health (toxicology and occupational health and safety)

Chemicals that are nominated for review are assessed for their effect on human health against the following criteria:

• Special concerns
  • demonstrated or potential adverse effects in humans.
• Acute and chronic risk.
• Scheduling of the chemical.
• Exposure to the chemical from food.
• Regulatory action taken overseas (for example, Canada, the European Union, the United Kingdom, the United          States of America).
• Hazardous substances.
• Other toxicity (health hazard).
• Industrial exposure in Australia.
• Form of concentrated chemical (includes formulated products).
• Exposure to working strength chemical (mixing, loading or application).
• Frequency of application.
• Post-application exposure (handling of treated crops and animals).
• Toxicity.
• User exposure.

Environment

Chemicals that are nominated for review are assessed for their effect on the environment against the following criteria:

• Environmental exposure
  • form and method of application.
  • volume of use (kilograms per annum).
  • scale of use (hectares per annum).
  • persistence (soil or aquatic half-life).
  • bioaccumulation potential.
  • mobility or leaching potential.
• Environmental toxicity.
• Aquatic toxicity.
• Terrestrial bird or mammalian toxicity.
• Terrestrial plant toxicity.
• Other non-target organisms.
• Sensitivity of receiving environment.
• Demonstrated adverse effects.
• Regulatory action taken overseas on environmental grounds (for example, the US Environmental Protection Agency, the Canadian Pest Management Regulatory Agency or the European Union).

Residues and trade

Chemicals that are nominated for review are assessed for their impact on residues and trade against the following criteria:

• Absence of maximum residue limits (MRLs).
• Reported incidents of residue violations.
• Reported incidents of adverse effects on trade.
• Compatibility with other countries' MRLs.
• International regulatory action.
• Residues resulting from use according to the label and the appropriateness of existing directions (for example, hydroponics versus field use).

Note: Dietary exposure is considered under human health.

Target crop safety

Chemicals that are nominated for review are assessed for their effect on target crop safety against the following criteria:

• Reported incidents of phytotoxicity and adverse interactions with target crops.
• Reported incidents of adverse effects to treated target animals.

Efficacy

Chemicals that are nominated for review are assessed for their efficacy against the following criterion:

• Lack of efficacy (confirmed report(s) of serious incident(s) of chemical failure; substantial incidents of chemical failure).

Chemicals nominated for reconsideration

Identifying and nominating chemicals for review is an ongoing process. The APVMA regularly assesses chemicals nominated for review to ensure the highest risks are being targeted based on up-to-date scientifically based information.

The reconsideration process is initiated when new scientific information raises concerns relating to the safety or effectiveness of the chemical.

The formal legislative process commences when the APVMA decides it is necessary to undertake a reconsideration and issues a legal notice to holders placing their approvals and registrations under review.

The APVMA follows a consultative process with the public, industry and federal and state government agencies to seek input on prioritising chemicals, or types of chemicals, that have been identified for review.

Currently, five chemicals have now been prioritised for detailed scoping prior to commencement of reconsideration. The remainder are to be prioritised for reconsideration after the first five have commenced the reconsideration process.

Currently there 13 chemicals or types of chemicals under review and 19 chemicals the APVMA had identified for future review. Five of these are currently being scoped prior to commencement of the review process.

Table 1.Current chemicals with reviews in progress, those that have be prioritised (1 to 5) for future reviews and those that have been identified for review but not yet prioritised.

Reason for reconsideration

1 Public health: Includes a consideration of mammalian toxicology and the risk to people from exposure to residues in food.

2 Worker safety: Includes a consideration of mammalian toxicology and the risk to people using chemical products, re-entering treated areas and handling treated materials.

3 Environmental safety: Includes a consideration of ecotoxicology, environmental fate and the risk to organisms from exposure to chemicals in the environment during use and remaining in the environment after use.

* Registered use in broadacre grain cropping.

More information on the chemicals under review, nominated and prioritised for reconsideration is available from: https://apvma.gov.au/node/10876

Table 2. Agvet chemicals with broadacre grains registrations for which reviews are completed with a brief description of the regulatory decision.

The cost of registration, reconsideration and its impact on chemical availability

The number of research-based companies involved in the discovery of new chemistries has been declining. In part this is due to the increasing costs of the discovery and development of new pesticides. The average cost to bring a new active ingredient to market from 2010-2014 was an estimated US$286 million – approximately US$134 million more than in 1995.

It is harder and harder to find new active ingredients, despite the fact that chemical companies are screening more molecules than ever before. Only one in 160,000 active ingredients discovered today will pass the rigorous testing requirements to become a registered pest management product.

The additional costs associated with product defence, when a chemical goes through the reconsideration process, can be extremely high if additional data is required to meet current regulatory scientific requirements/standards. A registrant investment decision takes into consideration these additional costs. For older, generic products such expenditure may never be recovered from the market place.

Conclusion

The greatest direct influence that grain growers can have on retaining access to agvet chemicals is to ensure that there are no adverse experiences. This can be achieved by using chemicals for their registered use and closely adhering to all label directions for use including application timing, rates, spray drift mitigation statements and withholding periods.

Failure to do so can result in exceeding of MRLs in commodities, the potential for environmental damage and human health risks. These outcomes then put additional regulatory focus on those agvet chemicals, adding to the body of evidence that may then result in a negative review for the grains industry, leading to further use restriction or cancellation of registrations.

Maintenance of access to agricultural chemicals for broadacre use is reliant on growers showing strong stewardship in following label directions and supporting registrants who invest in new use patterns, both with new actives and old off patent (generic actives).

Useful resources

Australian Pesticides and Veterinary Medicine Authority (APVMA): https://apvma.gov.au/

APVMA: Chemical Review: https://apvma.gov.au/

Contact details

Gordon Cumming
Grains Research and Development Corporation (GRDC)
0428 637 642
gordon.cumming@grdc.com.au