Application limits for a key potato sprout suppressant have been cut for the coming potato season and are likely to fall even further.

Chlorpropham (CIPC), an essential tool to control sprouting, is applied to about 3.5m tonnes of potatoes stored each year by about 1,000 growers.

See also: New campaign on the correct use of CIPC in potato stores

However, back in 2007 concerns over residues prompted the industry to set up the Potato Industry CIPC Stewardship Group and launch the “Be CIPC Compliant” campaign to promote best practice and eliminate exceedances.

Last week, the group announced that the Chemicals Regulation Directorate had approved new statutory label limits for the 2015-16 season of 30g/t for the fresh market and 50g/t for processing.

Potatoes for processing include those destined for fish and chip shops.

Also a statutory requirement is the latest time of application, which is 14 days before removal from store for sale or processing.

“Then from 2017, it is expected that new product labels will permit a total dose of no more than 36g/t,” says Adrian Briddon, secretary of the CIPC Stewardship Group.

“More importantly, it is anticipated, the conditions under which this may be applied, will be more strictly controlled on product labels.”

Best practice

Mr Briddon highlights best practice, in line with Red Tractor Farm Assurance, is just one application in cold stores before the temperature falls below 7C.

“If you use CIPC, you must check and adhere to the statutory conditions of use and, now more than ever, it is critical that users adopt best practice.” 
Adrian Briddon, CIPC Stewardship Group

The group recommends applications at full label rates should not be carried out unless best practice methods are in place and stores are suitable for effective distribution of the chemical.   

“Even modest doses (about 10-14 g/t) applied under conditions where best-practice modifications have not been adopted will increase the risk of a maximum residue level exceedance,” explains Mr Briddon.

“If you use CIPC, you must check and adhere to the statutory conditions of use and, now more than ever, it is critical that users adopt best practice.

“The easiest way of doing this is to use a National Association of Agricultural Contractors applicator and ensure that a store checklist is completed before any application is made.” 

The gradual annual reduction in CIPC total dose was requested by the companies that hold the approvals for formulations and was agreed with the Expert Committee on Pesticides.