Aldicarb chemical review

Aldicarb is a carbamate insecticide used in cotton, sugarcane and citrus crops for the control of mites, nematodes and other insect pests.

In December 1997, the APVMA announced its decision to review the registration of aldicarb. Aldicarb was nominated for review on environmental, public health and occupational exposure grounds. In the United States, human poisoning incidents and bird kills had been linked with the use of aldicarb. There was a concern that there might be potential for water contamination in high-use situations, such as in citrus growing. Contamination of groundwater has been linked to the use of aldicarb in the United States.

Preliminary review

In April 2001, the APVMA released the Preliminary review findings report for public comment. In the preliminary review, the APVMA looked at various issues and risks to human health from exposure during use and from dietary residues, as well as risks to the environment.

The APVMA did not recommend the cancellation of any products or uses. The registrations and approvals for aldicarb products remained the same, with only minor label and maximum residue limit (MRL) changes made.

Final review and outcomes

In July 2001, the APVMA released the Aldicarb review final report. In the report, the APVMA found that because of aldicarb’s presentation in granular form and its application method and use pattern in Australia, there was little likelihood of adverse human health or environmental effects arising from its use. Therefore, there was no reason for the APVMA to discontinue the registration of aldicarb. The APVMA found that:

• aldicarb use is not expected to be harmful to public health
• workers who follow good agricultural practice and label instructions are not at risk from exposure
• the risk of water contamination is low under Australian conditions.

The APVMA included new, stronger safety warnings on aldicarb product labels and changed the withholding period for sugarcane. The APVMA also included new directions indicating that cotton trash that has been treated with aldicarb should not be fed to animals.

In the final report, the APVMA recommended:

• changing product labels by:
  • strengthening first aid and safety directions, warning statements, and information on product labels for personal protective equipment and re-entry/re-handling periods
  • including an additional label warning: ‘dangerous to fish and aquatic invertebrates’
• strengthening safety, training and supply requirements by:
  • modifying product containers to reduce the risk of exposure while handling
  • requiring that a person using, keeping or disposing of aldicarb products should have completed an approved course of training and be issued with a specific certificate of accreditation
  • not using aldicarb within 15 metres of any drinking well
  • not using aldicarb within 150 metres of any drinking well where soils are sandy and the watertable is shallow
• strengthening use patterns by:
  • deleting MRLs for cereals, grapes, potatoes and strawberries, for which no registered use patterns exist
  • setting temporary MRLs for milks, meat, offal and sugarcane at or about the limit of analytical quantitation
  • revising withholding and feeding restrictions (a withholding period for sugarcane is not required when aldicarb is used as directed; cotton trash treated with aldicarb must not be fed to animals)
  • monitoring the use of aldicarb in citrus crops until 2004 (use on citrus grown on sandy soil is the most likely situation to cause water contamination, and the APVMA wanted to ensure that the levels of aldicarb used did not create a risk to the environment).