26 May 1995

Sprout suppressant review could mean tighter EU controls

ITS ALL action in the sprout suppressant sector. Hot on the heels of the UK green light for tecnazene (Arable, May 19), Cyanamid revealed its new product to growers at Potato Technology 95. And delegates at the preceding days conference heard how all four existing sprout suppressants are now undergoing EU review.

That review could bring tighter controls, particularly if a battle over proposed maximum residue limits goes against the UK. But all agree suppressants are essential. "We cant do without sprout suppressants," stresses the PMBs Adrian Cunnington. Refrigeration may stop sprout growth but the resulting accumulation of sugars can cause browning in cooked, processed products and poor taste in pre-packed tubers.

Stephen Crossley, of the Pesticides Safety Directorate in York, acknowledged the need for sprout suppressants to allow year-round storage. But he pointed out all four established materials must clear the hurdle of EU reviews.

Chlorpropham (CIPC), pro-pham (in Atlas Indigo, Luxan Gro-Stop and Pommetrol M), maleic hydrazide (Fazor) and tecnazene (Fusarex, Hickstor, Tecnazene, etc) are all involved, with results expected within a year.

To win through products need two things, says Mr Crossley. First, makers, or other bodies, must support them with required safety and toxicology data. And second, they must not pose an "unacceptable risk" to operator, consumer or environment. He expects them all to be approved. Any concerns, such as residues in river sediments downstream of processing plants, are likely to be met with label restrictions, rather than bans, he says. Maleic hydrazides exclusion from knapsack use is an example.

But the review will also establish uniform residue levels to apply throughout the EU. Those will help avoid trade problems such as Italys ban on imported Belgian chips which exceeded Italys MRL for processed products.

The danger is that a 5mg/kg MRL be imposed for tecnazene. That was vetoed by the UK on the grounds that it would be costly to achieve in box stores. French farmers are facing such costs now as they modify stores to meet the lower standard in France. The current proposal is for a more manageable MRL of 20mg/kg to be introduced.

Stephen Crossley of PSD.