TY - JOUR AU - Ajwa, Husein AU - Stanghellini, Michael AU - Gao, Suduan AU - Sullivan, David A. AU - Khan, Afiqur AU - Ntow, William AU - Qin, Ruijun TI - Fumigant emission reductions with TIF warrant regulatory changes JF - California Agriculture JO - Calif Agr Y1 - 2013/07/01 VL - 67 IS - 3 SP - 147 EP - 152 PB - University of California Agriculture and Nature Resources SN - 0008-0845 UR - http://dx.doi.org/10.3733/ca.v067n03p147 L3 - 10.3733/ca.v067n03p147 AB - With methyl bromide's phase-out, most growers have turned to alternative fumigants, particularly 1,3-dichloropropene (1,3-D) and chloropicrin. These alternatives are tightly regulated because they are classified as toxic air contaminants and volatile organic compounds; the latter combine with other substances to produce ground-level ozone (smog). Two ambient air monitoring studies were conducted to evaluate the potential of totally impermeable film (TIF) to reduce emissions from shank applications of chloropicrin and 1,3-D. In 2009, a study demonstrated that TIF reduced chloropicrin and 1,3-D peak emissions by 45% and 38%, respectively, but TIF did not reduce total emissions when it was cut after 6 days. In 2011, increasing the tarp period from 5 to 10 days decreased chloropicrin and 1,3-D peak emissions by 88% and 78%, and their total emissions by 64% and 43%, respectively. Concurrent dynamic flux chamber results corroborated the ambient air monitoring data. These studies provide regulatory agencies with mitigation measures that should allow continued fumigant use at efficacious application rates.