Dimethoate - frequently asked questions

Updated 24 September 2013

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About dimethoate

What is dimethoate?

Dimethoate is an insecticide and acaricide used in horticulture, grain production, cotton and domestic gardens.

What is it used for?

Prior to suspension of some uses in October 2011 (extended to October 2014), dimethoate was used:

  • both as a pre-harvest and post-harvest insecticide to control many common insect pests in a wide range of vegetables and fruit crops, as well as on ornamentals and flowers
  • as an integral part of fruit fly control in many areas of Australia. It was used as a quarantine treatment on fruit and fruiting vegetables to eradicate Queensland Fruit Fly before interstate trade within Australia and export to New Zealand. In addition, it is used to treat produce from fruit fly areas into fruit fly free or non-endemic areas.

Why is the use of dimethoate being reviewed?

The APVMA has a Chemical Review Program that considers new research or evidence regarding the use or safety of particular chemicals or products. Dimethoate was listed for review due to concerns about possible effects on human health and trade.

Early analysis has led to interim suspensions of some uses of dimethoate in advance of the completion of the review. The Preliminary Review Findings are yet to be completed.

How many products contain dimethoate?

There are currently 22 dimethoate products.

Who produces/manufactures the chemicals?

19 companies have dimethoate products. A list of these companies is available in the APVMA's Gazette notice (page x) (RTF, 921kb) | (PDF, 1.3Mb).

Is dimethoate used overseas?

Dimethoate is currently registered for use in a number of countries including the USA (on 35 food crops), Canada, European Union (EU) and New Zealand.

Suspension of dimethoate

What action is the APVMA currently taking on dimethoate?

On 6 October 2011 the APVMA suspended the use of dimethoate on many food crops due to potential dietary risks.

How long will the suspension last and what does it mean for users?

The suspension will last until 5 October 2014 while the Authority completes further assessments on the chemical. The suspension prohibits:

  • use of dimethoate on certain horticultural crops
  • use on all food producing plants in the home garden
  • supply and possession of dimethoate products unless they carry the new instructions for use: PER13155 and PER13156

The suspension applies to dimethoate uses on registered products and uses under permit.

How did the suspension come about?

The suspension follows the release of the 2011 Dimethoate Residues and Dietary Risk Assessment Report which found that its use on many crops could exceed the recommended public health standard (the Acute Reference Dose).

The risk assessment is a necessary component of the review and its purpose is to set Maximum Residue Limits for approved use patterns in food crops. Part of that risk assessment includes a dietary exposure assessment which looks at the potential for a consumer to be exposed to pesticide residues if they were to eat large amounts of food treated with that chemical. It includes a large margin of safety to protect all consumers.

The dimethoate assessment showed that potential exposures resulting from residues on some crops could reduce the margins of safety that are in place to protect consumers. The exceedance of the public health standard is a trigger for the APVMA to take regulatory action to ensure that consumers remain protected.

Download the 2011 Dimethoate Residues and Dietary Risk Assessment Report - August (PDF, 2.03Mb) | (DOC, 1.82Mb)

Will dimethoate be allowed to be used on the suspended uses again?

The suspension is not a cancellation of dimethoate products, it stops the use of dimethoate on certain crops while the Authority makes its final decision on the review.

Information for suppliers, growers and home garden users

What should I do if I am a supplier, distributor or retailer of dimethoate products?

You cannot supply or deal with any dimethoate products unless they are supplied with the new instructions for use.

Product registrants are requested to inform all parts of the supply chain that new instructions have been issued by the APVMA. All products in the supply chain and the marketplace must contain the new instructions prior to sale. View the new instructions for use: PER13155 and PER13156

For products used in the home garden, uses in food crops are prohibited, however use on ornamentals in the garden can continue. Further information specific to home garden uses.

All product manufactured after the suspension start date is legally required to be labelled (often in the form of an oversticker) with new instructions. Some product labels have been approved that are consistent with the suspension instructions and thus do not require additional labelling.

It is also an offence to advertise or promote the use of these suspended products although the publication of information related to the suspension itself is not an offence.

The APVMA will consider product recall action if it becomes aware that these new instructions are not being adhered to.

What do I do if I no longer have any need for my dimethoate product(s)?

Where applicable, excess product can be used for allowed uses as contained in the new use instructions.

If you wish to dispose of your products, please do so responsibly through the ChemClear program (external site).

How do I find out what dimethoate can still be used on?

The new instructions for use outline what crops the suspended products cannot be used on during the suspension period. Also the list of uses allowed to continue clearly indicates those crops on which commercial use can continue.

View the new instructions for use: PER13155 and PER13156

There are some other permits that allow specified uses of dimethoate that were not included in previous labels. These may be found by searching the APVMA permits database for current permits with the keyword "dimethoate".

What should I do if I have treated my produce with dimethoate on or prior to 6 October 2011?

Produce treated with dimethoate on or prior to 6 October 2011 can still be offered for sale after the date of suspension. The effect of the suspension is to stop use of dimethoate products after the specified date. Maximum residue limits (MRLs) for suspended uses will remain in place for some months to allow treated produce to be sold.

Alternatives to dimethoate

Are there any available alternatives to dimethoate?

Yes, there are registered alternatives to dimethoate for fruit fly control. Growers can search the APVMA’s database of registered products (PUBCRIS).

Fenthion products are suspended and growers should not consider it a permanent replacement for dimethoate for fruit fly control. The review of fenthion is ongoing and the APVMA has suspended certain uses of fenthion.

The APVMA has recently issued several permits as alternatives to dimethoate in certain crops. Details of these and other minor use permit applications currently under assessment can be found on the alternatives for fruit fly control webpage. In September 2013, the APVMA issued a new permit (PER14252) for the control of fruit fly in pomefruit, stonefruit and persimmons with a withholding period of 7 days.

How do I apply for a permit?

Information on the types of permits, criteria to be addressed and the permit application process is available on the Agricultural Permits webpage.

Is the APVMA required to find or recommend  alternative products for growers to use?

No. The APVMA's role is that of an industry regulator. It is not involved in identifying opportunities in the marketplace or promoting registration/approvals to meet market needs. It is up to chemical companies and individuals to identify a need and develop a suitable product. Alternatively, grower associations may identify gaps in the market and seek new product registrations through chemical companies or permits. Industry bodies and state authorities may assist in meeting identified needs.

Dietary risks

What is involved in a dietary risk assessment?

The dietary risk assessment determines the potential for effects on human health from exposure to treated produce. It is an estimate which looks at the potential for a consumer to be exposed to pesticide residues if they were to eat large amounts of food treated with that chemical. It includes a large margin of safety to protect all consumers.

The residue in the large amount of food is then compared to the Acute Reference Dose, the relevant health standard, set by the Office of Chemical Safety (external site), to see whether the exposure is acceptable.

The APVMA conducts this assessment on every new chemical before allowing its use in Australia. The purpose of the assessment is to set Maximum Residue Limits for any use approved in a food crop.

The exceedance of the public health standard is a trigger for the APVMA to take action to ensure consumers remain protected. The trigger for action is aligned with international best practice as recommended by the United Nations Food and Agriculture Organisation and World Health Organisation.

Where does the evidence of dietary risks come from?

The assessment of short-term dietary risks utilised residue data from research trials together with food consumption data to determine the likely exposure of children and adults to dimethoate residues on treated crops.

What do these dietary risks mean?

The 2011 Dimethoate Residues and Dietary Risk Assessment Report found that its use on many crops could exceed the recommended public health standard.

This means that the residues on some crops could reduce the margin of safety put in place to protect consumers.

The APVMA must therefore remove the use of dimethoate on certain crops so that consumption remains in line with the public health standard.

The dietary risk assessment for dimethoate did not raise any concerns about long-term risks to human health.

Food safety and supply

Are the fruit and vegetables that I have already bought safe to eat?

Yes. While the 2011 Dimethoate Residues and Dietary Risk Assessment Report shows some estimated exposures are above the Acute Reference Dose, safety margins are built in to protect consumers. The exceedance of the Acute Reference Dose is a trigger for the APVMA to take action to ensure consumers remain protected.

Regular surveillance of chemical residues on food by state, territory and federal agencies shows dietary exposure to pesticide residues is well below Australian or international reference health standards and there is no public health and safety risk.

Are there any health consequences from my previous exposure to dimethoate?

While the 2011 Dimethoate Residues and Dietary Risk Assessment Report shows some of the estimated exposures for consumers are above the Acute Reference Dose, these reduce, but don't breach margins of safety put in place to protect consumers.

These safety margins provide a protective buffer to ensure consumers will not actually be exposed to high levels of residues in food.

Surveillance of chemical residues on food by Food Standards Australia New Zealand (FSANZ) and other state, territory and federal agencies also regularly shows dietary exposures to pesticide residues are well below Australian or international reference health standards and do not represent a public health and safety risk.

What monitoring is undertaken to ensure my food is safe?

Find out more about Australia’s rigorous food safety program that ensures Australia’s food is safe to eat and free from harmful levels of pesticides.

Quarantine arrangements

How will the proposed suspension affect quarantine arrangements?

Treatment with dimethoate is mandated in some Interstate Certification Assurance (ICA) arrangements in quarantine requirements for trade to New Zealand and for fruit fly outbreak control in many states. The APVMA has no role in these arrangements other than granting approvals for use of chemical treatments.

Further information is available from:

International trade: Biosecurity Australia (external site)

Domestic trade

International regulatory status of dimethoate

What international action is being taken on dimethoate?

Dimethoate is currently registered for use in a number of countries including the USA, Canada, European Union (EU) and New Zealand and has been reviewed in the USA and the EU.

A review of dimethoate was completed by the US EPA in 2006, and a further review began in 2009 which is due for finalisation in 2015. The 2006 decision permitted the use of dimethoate in 35 food crops, whilst residential uses were voluntarily cancelled in 2000.

Dimethoate is currently approved in the European Union as a plant protection product (expiry Annex I listing 30/09/2017) and is authorised for use in 26 European countries.

How do the APVMA's standards compare to those of overseas countries?

The APVMA uses the same rigorous methods of dietary exposure assessment as are used internationally. These methods are endorsed by the UN World Health Organisation and are developed with human health and safety in mind.

The public health standards established in other jurisdictions are similar to those established by the Office of Chemical Safety (external site) for Australia.

Industry consultation

How has industry been involved throughout the review?

The APVMA advised industry groups of the review of dimethoate when it commenced in 2004 and since 2006, has provided updates via meetings with industry groups and state authorities. Industry has previously been alerted to the lack of residues data submitted to the review and that many crop uses were likely to have dietary exposure concerns.

State government agencies, farming and commodity groups have also been involved in a national response plan, established to develop viable alternatives should there be changes to the fruit fly control chemicals, dimethoate and fenthion, in Australia.

Read more about the National Response Plan (external site) in relation to APVMA reviews of dimethoate and fenthion (coordinated by the Domestic Quarantine & Market Access Working Group).

Did the APVMA consult before deciding to suspend some dimethoate uses?

Yes. On 22 August 2011, the APVMA announced a proposal to suspend dimethoate products as an interim regulatory action while it completes further assessments on the chemical.

Product registrants and permit holders were asked to 'show cause' as to why the proposed action should not be taken.

Industry and grower groups were also invited to submit information or data that may change the outcome of the dietary risk assessment.

During this time, the APVMA briefed industry and grower groups on the 2011 Residues and Dietary Risk Assessment Report through meetings coordinated by industry bodies in:

  • Bowen, QLD – 29 August 2011
  • Gatton, QLD – 31 August 2011
  • Bundaberg, QLD – 1 September 2011
  • Canberra, ACT – 5 September 2011
  • Perth, WA – 8 September 2011

Submissions closed on 13 September 2011.

The APVMA received 20 submissions responding to the proposed suspension and the residues report. Of these, 17 raised issues that were relevant to the proposed suspension action. The remainder raised issues related to the later progress of the review that may be considered prior to (or immediately following) the release of the Preliminary Review Findings.

Submissions were received from product registrants, state authorities and representatives of the apple, berry, cereal grains, chilli, melon, pulse, strawberry, tomato processing, stonefruit and cherry industries as well as from Growcom and AUSVEG.

The submissions provided valuable information that the APVMA has used in considering alternative use patterns and thereby allowing some modified uses to be retained during the suspension period.

In making its decision does the APVMA assess trade impact?

The Authority has to consider the trade risks in using a chemical, but it cannot delay the withdrawal of use of a product where human health or environmental concerns have been identified. The assessment on the impact to trade is limited to trade betwenn Australia and other countries, not trade within Australia. A full trade assessment will be included in the Preliminary Review Findings report.

About the review of dimethoate

What is the next step in the APVMA's review of dimethoate?

The next step in the review of dimethoate is to publish the Occupational Health and Safety assessment and then publish the preliminary review findings. Preliminary review findings are expected to be published during the suspension period.

Read more about the dimethoate review process.

Why has the review taken so long?

Many chemicals undergo continued assessment by the APVMA. Interim regulatory actions and other measures are often taken throughout the review process to address urgent concerns.

Last updated on 24 September, 2013

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