There are growing fears over the Chemicals Regulation Directorate’s new interim measures for aquatic buffer zones, which could see a significant reduction in cropped land area for some key pesticides.

The British Crop Production Council (BCPC) is seeking justification for the much wider aquatic buffer zones resulting from the first new registrations under this interim system.

Dimethachlor requires a 10m buffer zone and diflufenican requires a 12m strip. But if the same method was applied to chlorpyrifos, a 75m buffer zone would be required, even though 20m is the maximum, said BCPC. These buffer zones apply to all watercourses, big or small, though only when there is water in the watercourse.

“These are worryingly large increases in width,” said BCPC chariman Colin Ruscoe. “The reduction of available productive land that will result from these zones goes against the drive for sustainable intensification.

“The move will also be counterproductive because farmers will avoid using products requiring wide buffer zones altogether, resulting in greater reliance on fewer products/modes of action – so risking faster development of pesticide resistance. This will increase the problems of the reducing number of products that will be available due to new EU regulations,” said Dr Ruscoe.

Under the previous LERAP scheme, growers could reduce the buffer zone width, by using lower doses and/or reduced drift spraying techniques. But products given any zone greater than 5m under the new arrangement will not be eligible for a reduction through the LERAP.

He said this inflexible approach offers no incentive for growers to adopt drift reducing equipment and techniques. “The old approach resulted in the use of lower drift air-induction nozzles for most spray operations – and new engineering solutions can reduce drift even further.

Dr Ruscoe also questioned whether the present practices and products do threaten water quality. “Point source and run-off can be far greater threats to water sources than spray drift.

“Only 1% of water bodies monitored by the Environment Agency failed their environmental quality standards for pesticides in 2010, with no evidence that these were due to spray drift. Furthermore, these water bodies were lakes and rivers – not farm ditches, many of which are not sustained aquatic ecosystems.

“The French authorities require buffer zones just for larger on-farm streams and water bodies that may have sustained aquatic ecosystems.”

More on this topic

Read more on the interim measures

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