Developing Global Leaders for Research, Regulation, and Stewardship of Crop Protection Chemistry in the 21st Century.

To provide sufficient food and fiber to the increasing global population, the technologies associated with crop protection are growing ever more sophisticated but, at the same time, societal expectations for the safe use of crop protection chemistry tools are also increasing. The goal of this perspective is to highlight the key issues that face future leaders in crop protection, based on presentations made during a symposium titled "Developing Global Leaders for Research, Regulation and Stewardship of Crop Protection Chemistry in the 21st Century", held in conjunction with the IUPAC 13th International Congress of Pesticide Chemistry in San Francisco, CA, USA, during August 2014. The presentations highlighted the fact that leaders in crop protection must have a good basic scientific training and understand new and evolving technologies, are aware of the needs of both developed and developing countries, and have good communication skills. Concern is expressed over the apparent lack of resources to meet these needs, and ideas are put forward to remedy these deficiencies.

Pyrethroid mode(s) of action in the context of Food Quality Protection Act (FQPA) regulation.

A Scientific Advisory Panel (SAP) in June 2009 concluded that a common mode of action existed for pyrethroids, with two subgroups. The purpose of this SAP was to advise the U.S. Environmental Protection Agency on the validity of regulation of pyrethroids as a single class under the Food Quality Protection Act of 1996. Two types of pyrethroid action were first described for clinical signs in the rat and clinical signs/nerve effects in the cockroach. In insects, Type I clinical signs correlate with repetitive firing in nerve axons, especially fine sensory axons. The Na(+) inward current is via a TTX-sensitive voltage-gated sodium channel (VGSC). Type II (α-CN) effects on VGSCs do not include repetitive firing following stimulation in these axons. Instead, Type II effects on VGSCs include prolonged Na(+) tail currents along with depolarization of nerve membrane. Other Type II effects have been measured on VG Ca(2+) and K(+) channels and VG and GABA-activated Cl(-) channels. In conclusion, in vivo pyrethroid effects in mammals should be linked with specific channel effects, allowing the use of specific clinical signs or ion channel effects for pyrethroid risk assessment.