I developed a spreadsheet a year ago to track compliance with the
acetochlor conditional registration use reduction triggers. I have updated
the spreadsheet with crop year 1996 data for the six other
herbicides and acetochlor -- percent acres treated, applications per acre,
rate, pounds applied, and changes since 1992 and 1994. A copy of the full
spreadsheet will be placed on the PMAC web page at
<http://www.pmac.net/acet96/htm>, along with my analysis, by the a.m.,
1996 use data make it clear that the registration of acetochlor has
not markedly changed reliance on and use of high-risk corn herbicides. EPA
based its decision, made reluctantly, in large part on a projected 33%
reduction in the application of six other corn herbicides. By one key and
direct measure, use has actually gone up since the registration of
acetochlor in 1994.
Acetochlor has been on the market for three crop years. The first two
seasons saw dramatic growth in acres treated and pounds applied, almost
completely away from alachlor and to acetochlor. Given the almost
one-for-one shift in acres between these two closely related products, the
net impact on corn herbicide use since the 1994 introduction of acetochlor
boils down to a one-to-one comparison of alachlor and acetochlor use
patterns. Here, the use data is pretty clear --
* Most of the shift in acres occurred in 1994 and 1995; the corn herbicide
market settled down markedly in 1996, even though acreage jumped from 64.1
to 70.2 million acres planted; most indicators of use and reliance were
largely unchanged on a per acre basis, the most logical way to assess trends
in reliance at the farm level.
* Acetochlor is being applied at about 115% the rate of alachlor, not the
projected one-third less. (Average acetochlor application rate in 1996 was
1.88 pounds a.i.; average alachlor rate, 1.64 pounds a.i. per acre).
* The sum total of the six a.i. pounds applied in 1996 -- 115,618,000
pounds, or 1.65 pounds a.i. per acre.
* Total six a.i.'s plus acetochlor pounds applied in 1996 -- 145,468,000, or
2.07 pounds per acre.
* On a per acre basis, six a.i. plus acetochlor use is down 0.14 pound per
acre from 1992, a 6.3 percent drop, but has risen 3.5 percent since 1994,
from 2.0 to 2.07 pounds per acre.
* Total pounds applied of the six a.i.'s plus acetochlor is up over 20
million pounds from 1994 -- the year of acetochlor's introduction.
* Conditional registration of acetochlor has changed market share between
two herbicides posing comparable risks, but has not altered markedly
reliance on high-risk corn herbicides.
* Passage of the FQPA, growing evidence of widespread contamination of
drinking water in areas where substantial corn acreage is treated with
acetochlor (see the recent EWG report for the latest data), and trends in
reliance on high-risk corn herbicides is likely to lead to re-evaluation of
the 1994 decision to conditionally register
Further analysis will be carried out on these numbers. The EPA
decision on canceling acetochlor's conditional registration will no doubt be
driven by, and made within the schedule for FQPA decisions just announced by
EPA (see PMAC web page, "FQPA Implementation" for full text). There will be
at least one more year's use data before the final EPA action.
Charles Benbrook 208-263-5236 (voice)
Benbrook Consulting Services 208-263-7342 (fax)
3100 Pack River Road firstname.lastname@example.org [e-mail]
Sandpoint, Idaho 83864 http://www.pmac.net