Risk-indexed herbicide taxes to reduce ground and surface water pollution: an integrated ecological economics evaluation

Public policy toward pesticide use in agriculture can benefit from data coming from models that integrate ecological and economic constraints into cropping decisions and pesticide use. Herein we use such a model to focus on the environmental and economic effectiveness of a specific set of tools used to promote sustainable agriculture with less pesticide runoff - incentive-based instruments created by risk-indexed herbicide input-taxes. We measure risk by health advisory levels and by an ecological economic simulation model that estimates predicted exposure levels. We explore whether this innovative solution or herbicide input-taxes does better at reducing losses to farm net returns, and surface and groundwater loadings than quantity restrictions. Using the integrated CEEPES model, our results suggest that risk-indexed input taxes by information about individual herbicide exposure levels can be a cost-effective tool to reduce predicted groundwater exposures. No single policy, however, was efficient at simultaneously improving groundwater and surface water quality. Instead we construct an efficient policy set. We find exposure-induced taxes were most efficient for small percentage reductions in overall exposure, bans were efficient for medium reductions, and flat taxes were efficient for high reductions. (C) 2001 Elsevier Science B.V. All rights reserved.