ABSTRACT
The development of herbicide-tolerant plants (HTPs) is the most frequent and arguably the most controversial application of genetic engineering to plants. This chapter discusses the environmental concerns about herbicides and HTPs. It explains why Environmental Protection Agencies (EPAs) current regulations and policies under Federal Insecticide Fungicide and Rodenticide Act (FIFRA) will likely fail to adequately protect human health and the environment because they leave significant risks associated with HTPs unregulated. The chapter presents several proposals for regulating HTPs under FIFRA. Toxicological studies indicate that bromoxynil, which originated in 1963, is dermally absorbed and is a developmental toxicant in laboratory animals. Thus, children of farm workers exposed to bromoxynil may suffer birth defects. Considerable evidence indicates that 2,4-dichlorophenoxy-acetic acid (2,4-D), which originated in 1942, causes cancer. A recent study by National Cancer Institute researchers indicated that pet dogs exposed to 2,4-D-treated lawns develop cancer more often than other dogs.
