Little use of biological alternatives to chemical pesticides

The increasing demands from many consumers in this day and age for fruit and vegetables which have been grown free of chemical pesticides, has put scientists under pressure to find biological alternatives.

A new study, funded by the Economic and Social Research Council (ESRC), has examined why there is currently such little use of biological alternatives in the UK.

According to research, biological products, known as biopesticides, can play a significant role in a more sustainable food chain as chemical pesticides are withdrawn due to resistance problems or because they are no longer commercially viable - chemicals also endanger workers' health and can contaminate groundwater.

Lead researcher, Professor Wyn Grant, at the University of Warwick, says it is evident that biopesticides have a potentially important contribution to make to a competitive agriculture industry.

Professor Grant says they have the potential to increase consumer confidence in fruit and vegetables whilst moving away from a polarised and over-simplified choice between conventional and organic modes of production.

The research suggests that consumer concerns about toxic residues could undermine the recommended 'five a day' target for the consumption of fresh fruit and vegetables and while supermarkets have responded to consumer pressure by banning some approved pesticides, they have been slow to embrace biopesticides.

Scientists say biological control agents such as naturally occurring fungi, bacteria or viruses are applied in much the same way as chemical pesticides to fight insect pests, but have obvious benefits as they have little impact on other organisms, are compatible with other natural enemies, do not leave toxic residues and are relatively cheap to develop.

These attributes far outweigh the disadvantages of lower effectiveness and a shorter shelf life and why has there been such poor uptake in Britain is a mystery.

According to the study because the regulatory system in the UK was developed with chemical pesticides in mind, it does not encourage the development of biopesticides.

In recognition of this, the regulator - the Pesticides Safety Directorate (PSD) - lowered registration fees and created a Biopesticides Champion in 2006 which has led to a modest increase in the number of biological products being registered, with others in the pipeline.

The researchers have pinpointed a lack of mutual recognition between EU member states as a key reason why the United States has a much higher rate of biopesticide use and this makes it hard for the small companies - often start-ups - that usually develop biopesticides to obtain economies of scale.

The study says new chemical formulations could be used to solve problems with biopesticide storage and efficacy and this might lead to greater interest from large businesses.

Biopesticides need to be fitted into current environmental stewardship schemes to provide incentives for their use and consumers need to be educated about biopesticides - they should also be given a different name with less negative connotations.

The researchers also suggest providing an ethical marque for products.

They say risks, costs and benefits need to be shared out between the manufacturer, regulator, government and consumers and they propose a framework to promote innovation within the regulator.

This includes pressure applied from central government, the appointment of key individuals to drive through change and for regulators to develop their expertise and commercial or financial pressure.

The researchers say the absence of a Europe-wide market for biopesticides is a significant obstacle to their wider commercial availability.

Though moves are underway to remedy this, they also suggest there is inconsistent interaction between the regulator and retailers, and a lack of involvement of environmental groups, due to indifference rather than hostility.