Properties and Uses of Chlorpyrifos in the United States - Reviews of Environmental Contamination and Toxicology - page 22

4.1 Formulations of Chlorpyrifos

CPY is currently available as a granular formulation and as several spray formula-
tions. CPY is widely effective against many different insects in various habitats that
may attack crop throughout the year. Therefore, it has a wide variety of applications
and may be applied to foliage, soil, or dormant trees. Application might occur pre-
plant, at-plant, post-plant or during the dormant season using aerial equipment,
chemigation systems, ground-boom sprayers, air-blast sprayers, tractor-drawn
spreaders, and hand-held equipment. Dow AgroSciences (and its predecessors)
originally developed CPY, but it is now also produced and/or marketed by other
registrants of pesticides. The analysis of uses covered in this paper addresses only
those CPY products that are registered by Dow AgroSciences, including Special
Local Needs labels (SLNs, FIFRA section 24c) for specific States in the U.S. that
are based upon these products.
Lorsban 15G ® is a granular formulation that contains 15% (wt/wt) CPY (a.i.) in
a solid matrix (Dow AgroSciences 2008 ). It is used primarily as a soil insecticide,
although it can be applied into the whorls of corn to control European corn borer.
Applications are in-furrow, banded, and broadcast. One “special local needs” label
(FIFRA section 24c State label) was found for use on ginseng in Michigan.
Lorsban 4E ® is an emulsifiable concentrate that contains 44.9% (wt/wt) a.i.
(479 g L −1 = 4 pounds of per gallon) (Dow AgroSciences 2004 ). It is used both
directly on plants and as a soil treatment. Foliage and woody parts of plants can be
treated. Treatments of soil are by broadcast, banded, side-dress, or, for onions and
radishes, applied in-furrow. Chemigation is specified for some treatments. There are
a few special local needs (24c) labels for the Lorsban 4E, but many old ones have
expired and appear to have been replaced by similar labels for Lorsban Advanced ® .
Lorsban Advanced ® is a newer, low odor, water-based version of Lorsban 4E that
contains 40.18% a.i. (wtwt) (450 g L −1 = 3.755 lb. a.i. per gallon) (Dow AgroSciences
2010 ). It is used in the same ways as the 4E formulation but contains smaller quanti-
ties of volatile solvents, thus reducing air pollution by VOCs. There are a number of
special local needs (24c) labels for Lorsban Advanced that both modify application
methods and rates and for several additional crops.
Lorsban 75WG ® was registered by EPA late in 2011 (Gowan 2011 ), but is not yet
listed among Dow AgroSciences products. It contains 75% a.i. (wt/wt) as water
dispersible granules for use in many of the same crops as the Lorsban 4E and
Lorsban Advanced formulations. One special local needs (24c) label for peppers in
Florida was found that referenced Dow AgroSciences as the registrant, although
Gowan Company was the distributor.
Lorsban 50 W ® is a water soluble formulation that contains 50% a.i. (wt/wt)
and is used for treating seeds in commercial establishments (Dow AgroSciences
2007 ). It is not permitted for such use on farms and other agricultural sites. It
does, however, have a supplemental label for use on unspecified trees in the east-
ern U.S. The treatment is to trunks of trees at a rate of 3 lb a.i./100 gallons of
spray, but no amount or limit per acre is specified. A similar use for Lorsban
Advanced is only for apple trees in the eastern U.S., but the Lorsban 50 W label
is not limited to any species of tree.