Variation in pesticide hazard from arable crop production in Great Britain from 1992 to 2002: Pesticide risk indices and policy analysis

Attempts to direct policy according to scientific findings are hampered by the multidimensionality of the potential impacts of pesticides which may affect consumers, operators, wildlife and the environment. Pesticide risk indices seek to reduce these multidimensional impacts to a single dimension and are increasingly used to understand variation in the hazard inherent in pesticides at the farm, regional and national scale. In this study, we used one such risk index, the Environmental Impact Quotient (EIQ), to estimate the hazard posed by pesticide usage from 1992 to 2002 on four UK grown arable crops (wheat, winter barley, spring barley and oilseed rape).Results are reported for three key indicators of hazard. Firstly, the EIQ which rates a pesticide's hazard profile. Secondly, the Environmental Impact (EI) which is the product of the EIQ rating and data on actual usage of a pesticide at a GB level in a given year, and provides an indication of the overall hazard arising from actual historical use at a national scale. Thirdly, EI per hectare standardises the hazard by dividing total EI in year by the area of crop grown in that year.The results suggest that between 1992 and 2002, the overall hazard posed by the pesticides applied to these crops declined substantially, as evidenced by a 10% decrease in pesticide usage, an 8% increase in yield per hectare, a 14% decrease in overall EIQ rating, a 15% decrease in EI rating and a 7% decrease in EI per hectare. Both Government and the industry may wish to take some encouragement from these trends, which seem to be wholly in line with societal demands of agriculture.