The California Department of Pesticide Regulation (DPR) has announced that pesticide volatile organic compound (VOC) emissions dropped 30 percent from 1990 to 2008.

This is largely as the result of new, lower emissions fumigation practices, a move to lower VOC formulations of non-fumigant pesticides, and relatively low overall pesticide use in 2008.

Soil fumigants have been identified as a major source of smog-forming pesticide VOC emissions along with emulsifiable concentrate formulations of non-fumigant pesticides.

DPR in early 2008 enacted new rules that severely restrict application methods, timing, and volume of all commonly used fumigants during the peak ozone period from May 1 to Oct. 31 in the California’s San Joaquin Valley.

The restrictions are intended to reduce pesticide VOC emissions by 12 percent compared to 1991 levels as required by a 2006 court order. The recent DPR report reveals that efforts by almond growers and other users of soil fumigants are helping DPR meet that mandate.

New application requirements include the use of tarps, spot treatments, and minimum soil moisture requirements. The Almond Board of California continues to fund research that will help almond growers reduce VOC emissions while maintaining efficacy and worker safety in soil fumigant applications.

Additionally, registrants have introduced lower VOC formulations for several key almond insecticides, including Lorsban, Prowl, and AgriMek, which are helping growers continue using key crop protection products while reducing VOC emissions.