Reassessment of Commodity Tolerances that are

Insignificant Contributors to the N-methyl Carbamate Cumulative Risk

June 29, 2006

I. 	Background and Introduction  

The Food Quality Protection Act (FQPA) of 1996 requires EPA to consider
available information concerning the cumulative effects on human health
resulting from exposure to multiple chemicals that have a common
mechanism of toxicity.  In 2001, EPA concluded that the N-methyl
carbamate (NMC) pesticides share a common mechanism of toxicity and
therefore require a cumulative assessment under FQPA.  The ten
pesticides in the NMC common mechanism group are aldicarb, carbaryl,
carbofuran, formetanate hydrochloride, methiocarb, methomyl, oxamyl,
pirimicarb, propoxur, and thiodicarb.  The Agency’s tolerance
reassessment decisions for these ten NMC pesticides must be based on the
interim tolerance reassessment decisions for each individual compound,
as well as the NMC cumulative assessment.  EPA released the Preliminary
Assessment of Cumulative Risk from N-Methyl Carbamate Pesticides in
August 2005.

As part of its ongoing work to complete the NMC cumulative assessment,
EPA has determined that 144 of the NMC tolerances are insignificant
contributors to the overall dietary exposure to the NMCs.  These
commodity/chemical combinations, when considered together, make such a
minor or negligible contribution to the cumulative risk of the NMCs that
the addition or subtraction of those uses from the risk cup would have
no quantified significance and would therefore have no impact on whether
the NMCs as a group meet the FQPA safety standard in section 408(b)(2)
of the Federal Food, Drug and Cosmetic Act (FFDCA).  Because these uses,
by themselves, add no meaningful risk, and because, as a result, they
will have no effect on the retention or revocation of other NMC
tolerances, EPA intends to count these negligible uses as reassessed
before the final NMC cumulative assessment is issued.  As described in
detail below, the Agency has taken a conservative, health-protective
approach in determining the criteria for this analysis and is thus
confident that these tolerances can be considered to be reassessed as
required under section 408(q).  

	For each of the 144 tolerances being reassessed at this time, the
Agency has issued an Interim Reregistration Eligibility Decision (IRED)
which found that, apart from consideration of the potential cumulative
risks from all of the NMCs, each tolerance would meet the section
408(b)(2) safety standard.  EPA has also considered the impact of these
tolerances on the NMC cumulative risks and has determined that they make
an insignificant contribution to the overall risks from the NMCs. 
Therefore, these tolerances will be maintained regardless of the outcome
of the NMC cumulative assessment and any potential regulatory action
taken as a result of that assessment.  Accordingly, EPA believes it is
appropriate to consider these 144 tolerances reassessed for the purposes
of FQPA section 408(q) as of today’s date, June 29, 2006.

NMC Tolerances Requiring Reassessment under FQPA

FQPA required EPA to reassess all tolerances in existence when FQPA
became law on August 3, 1996.  For the ten pesticides in the NMC common
mechanism group, there were a total of 320 tolerances that required
reassessment because they were in existence on the day that FQPA was
enacted.  

To date, ninety-two of the 320 NMC tolerances requiring reassessment
under FQPA have already been reassessed.  The ninety-two tolerances
include seven methiocarb tolerances, eighty methomyl tolerances, and
five thiodicarb tolerances.  The methiocarb tolerances are considered
reassessed because all methiocarb tolerances were revoked in 1998.  The
methomyl and thiodicarb tolerances are considered reassessed because EPA
issued REDs and associated tolerance reassessment decisions for methomyl
and thiodicarb in 1998, prior to the Agency’s determination that these
compounds would be part of the NMC common mechanism group.  Please see
Table A.6 in the Appendix for a listing of the reassessed tolerances for
methiocarb, methomyl, and thiodicarb.  

Determination of Insignificant Contributors

This section describes the procedures EPA followed to determine the
number of NMC tolerances that could be reassessed based on an
insignificant contribution to the total NMC risk in food.  These NMC
tolerances, termed Insignificant Contributors, are the subset of NMC
crop/chemical combinations that, when expressed in terms of
index-chemical equivalents and considered together as part of a
cumulative risk assessment, contribute to only a small fraction of the
NMC cumulative risk from food.  Such a designation to specific
crop/chemical combinations permits the Agency to conclude that the
contribution to dietary risk of the NMC tolerances associated with these
crop/chemical combinations is relatively small and that these tolerances
can thus be reassessed prior to EPA’s issuance of the revised NMC
cumulative risk assessment.  Only tolerances for NMCs with completed
IREDs were eligible for designation as Insignificant Contributors.

The Agency notes that this is a screening-level assessment designed to
ensure that risk will not be underestimated.  EPA fully expects that
additional NMC tolerances will be eligible for reassessment in the near
future when the Agency issues the revised NMC cumulative assessment,
which will use more refined information.        

Hazard/Relative Potency Factors

In the current analysis, EPA used the relative potency factors (RPFs)
and points of departure established in the preliminary cumulative risk
assessment (August 2005) for brain cholinesterase inhibition.  For
details about the data and methods used to derive these values, please
refer to Chapter I.B and associated appendices and data sets in the
preliminary cumulative risk assessment (August 2005) (available at  
HYPERLINK "http://www.epa.gov/pesticides/cumulative" 
http://www.epa.gov/pesticides/cumulative ).  The Agency used benchmark
dose (BMD) methods to estimate the dose expected to result in 10% brain
cholinesterase inhibition (BMD10) in adult rats following acute
exposures.  EPA calculated RPFs by dividing BMDs for specific pesticides
by the BMD for the index chemical, oxamyl. 

The Agency anticipates that most of the RPFs and points of departure
used in this Insignificant Contributors analysis (and also in the August
2005 preliminary NMC cumulative assessment) will be substantially
similar to those that will be used in the forthcoming revised NMC
cumulative assessment.  If some values do differ, it will be because the
revised cumulative assessment uses values that have been further refined
based on recently-submitted data.  

Dietary Exposure

EPA began the process of identifying Insignificant Contributors by
performing a baseline dietary exposure analysis.  The baseline
assessment for the Insignificant Contributors analysis used the same
residue and consumption data from the August 2005 preliminary NMC
cumulative risk assessment (except that 2004 PDP data were also
included), and it also included similar assumptions about processing
factors, zero residues, and crop translations.  

EPA used pesticide residues reported in PDP from 1994-2004 (registered
or not) from all ten NMC pesticides for this Insignificant Contributors
analysis.  The PDP residue data were further extended (translated) to
other commodities identified as reasonable for translation of pesticide
residue data per Agency policy.  Residues from fish and eggs were not
included in this assessment and, based on examination of FDA monitoring
results, are not anticipated to contribute significantly to risk
associated with the NMC pesticides.  However, recent PDP data on beef,
pork, and poultry were included in the assessment.  Together, the food
commodities in the PDP program and those commodities to which the
residues are translated account for greater than 90%-95% of children’s
diets.  Exposure for children 1-2 years of age was earlier identified as
of specific interest since this was the subgroup with the highest
exposure in the preliminary NMC cumulative risk assessment.  Dietary
(food only) exposure was estimated using the Dietary Exposure Evaluation
Model (DEEMTM) software which incorporates the 1994-96/1998 USDA
continuing Surveys for Food Intake by Individuals (CSFII) data and
EPA’s Revised Food Commodity Intake Database (Revised FCID).  For more
information, please refer to Chapter I.C and the associated appendices
and datasets in the preliminary NMC cumulative risk assessment.  

As described in more detail in the preliminary NMC cumulative
assessment, EPA adjusted the amount of residue of each chemical by
multiplying by an RPF to obtain the equivalent residue of an index
chemical and summed these within each sample.  The new calculated
residue is termed the Index Equivalent Residue (ResidueIE) and the
exposure value resulting from combining ResidueIE and consumption is
termed the Index Equivalent Exposure (ExposureIE).  EPA calculated
Margins of Exposure (MOEs) by comparing the potency adjusted exposure to
the point of departure for the index chemical (ie, oxamyl).    

Figure 1 below provides a graphical description of the major
contributors to the baseline cumulative dietary risk when all 10 NMCs
are included.

Figure 1.  Plot of major contributors to the NMC cumulative risk from
food

Criteria for Designation as an Insignificant Contributor

EPA established several criteria for designating crop/chemical
combinations as Insignificant Contributors.

Crop/chemical combinations that produce an MOE greater than 1000 when
considered together are Insignificant Contributor tolerances.  

The Agency selected 1000 as a highly-conservative point of comparison,
incorporating a 10x for interspecies extrapolation, a 10x for
intraspecies extrapolation, and a 10x FQPA safety factor for protection
of infants and children.  The assignment of a value of 10x for the
interspecies extrapolation factor is conservative given that human
studies are available to inform the chemical-specific interspecies
factor for some NMCs.   The assignment of a value of 10x for the FQPA
safety factor is also conservative given that there are studies
available for some NMCs which compare the relative sensitivity in
juvenile and adult rats, and which will be used to inform the
chemical-specific FQPA factors.  

Only tolerances for chemicals with completed IREDs are eligible for
designation as Insignificant Contributors.     

Any pesticide/crop combination with NO detects in all years of PDP
monitoring was considered an Insignificant Contributor.

Meat, Milk, Poultry and Egg tolerances for which exposure is deemed
negligible were considered Insignificant Contributors.

Livestock feedstuffs associated with the meat, milk, poultry, and egg
samples with few, small, or no detectable residues were considered
Insignificant Contributors.

Procedure for Identifying the Insignificant Contributors

	

As described in section II of this document, there were a total of 320
NMC tolerances that required reassessment because they were in existence
on the day that FQPA become law.  Ninety-two of the NMC tolerances have
already been reassessed (7 methiocarb tolerances, 80 methomyl
tolerances, and 5 thiodicarb tolerances).  So, EPA used 228 tolerances
as the starting point for the ‘Insignificant Contributors’ analysis.
 

EPA notes, however, that some methomyl uses appear to be contributors to
the cumulative food exposure assessment.  Thus, the
previously-reassessed methomyl tolerances were reintroduced into the
analysis and methomyl is included in the cumulative dietary risk
analysis described below.  Methomyl does in fact contribute to the MOEs
provided in Table 1, and the tolerance count is given in two different
ways in Table 1, to reflect the status of the methomyl tolerances. 

EPA has developed the list of Insignificant Contributor tolerances using
the stepwise approach described below.

EPA performed a baseline cumulative dietary analysis using all 10 NMCs. 

EPA removed all tolerances for aldicarb and carbofuran.  The IREDs for
these two NMCs have not yet been completed as of June 29, 2006, and
therefore these tolerances are ineligible for Insignificant Contributor
designation.

EPA performed a cumulative dietary analysis of the remaining potential
Insignificant Contributor crop/chemical combinations.  The results are
displayed in Figure 2.  The plot provides a rank order of the
chemical-commodity combinations that contribute to the NMC cumulative
food exposure assessment. 

EPA removed from the analysis, in groups of several tolerances, the
crop/chemical combinations which made the highest contribution to the
cumulative risk.  The DEEM-estimated MOEs that resulted from the
sequential removal of each group of tolerances are provided in Table 1. 
The “removed” crop/chemical combinations in column 1 of Table 1 are
not deemed Insignificant Contributors at this time because they
potentially contribute to NMC cumulative risk (i.e., they are
responsible, jointly, for MOEs less than 1000).

EPA repeated the removal process described in step 4 until the MOEs at
the 99.9th percentile of exposure exceeded 1000 for children age 1-2,
the population subgroup determined to have the lowest MOEs.  EPA’s
analysis of risk to this population subgroup is therefore protective of
all other population subgroups groups.  

All remaining crop/chemical combinations are considered Insignificant
Contributors since, when considered together, they contribute only minor
amounts to risk, with MOEs of greater than 1000.   

  

Figure 2.  Plot of major contributors to the NMC cumulative risk from
food, excluding aldicarb and carbofuran

Results of the Insignificant Contributors Analysis

Table 1 presents a summary of the results of the Insignificant
Contributors analysis.  The table shows, sequentially, the crop/chemical
combinations that were removed at each step in the process.  The table
also provides the number of tolerances removed that were associated with
the these crop/chemical combinations, the number of tolerances that
remain, the associated MOE, as well as a reference run identification
number for the DEEM computer files used to produce these exposure
estimates (the DEEM files are provided on the NMC cumulative web page at
www.epa.gov/pesticides/cumulative).   Table 1.  Summary of
Insignificant Contributors analysis conducted with DEEM

Scenario*	Number of Crop/Chemical Combinations Removed	Number of
Tolerances	MOE	Ref.

Run ID



NMC tolerances (excluding those previously assessed)	All NMC 

tolerances 





Baseline (all NMCs)

	0	228	320	31	1

Remove all aldicarb and carbofuran crop/chemical combinations 	62	166
258	49	2

Remove 12 crop/chemical combinations – methomyl on strawberry,
cucurbits, and grape; carbaryl on strawberry, pome fruit, plum, and
peach; formetanate hydrochloride on nectarine, plum (no tolerance), and
peach; and oxamyl on summer squash and cucumber.	12	158	247	154	3

Remove 7 crop/chemical combinations – carbaryl on grape; formetanate
hydrochloride on apple; methomyl on spinach, lettuce, cabbage, and
peach; oxamyl on apple	7	155	240	348	4

Remove 6 crop/chemical combinations – formetanate hydrochloride on
pear; carbaryl on apricot and beans; and oxamyl on celery and
watermelon; methomyl on plum (no tolerance)	6	150	235	

519	5

Remove 6 crop/chemical combinations – formetanate hydrochloride on
apricot (no tolerance); carbaryl on citrus fruit and peppers;  oxamyl on
bell pepper; methomyl on apple and succulent beans	6	147	230	783	6

Remove 5 crop/chemical combinations – carbaryl on nectarine and
cherry;  oxamyl on pear; methomyl on orange and tomato	5	144	225	1224	7

* Italicized crop/chemical combinations are ones for which there are no
tolerances, or for which tolerances were previously reassessed (i.e.,
methomyl).

A total of 144 of the 228 NMC tolerances that remain to be reassessed
meet EPA’s criteria for designation as Insignificant Contributors due
to no exposure or low exposure.  A total of 84 tolerances do not meet
the Agency’s criteria for designation as Insignificant Contributors,
either because they are aldicarb or carbofuran tolerances, or because
their inclusion in the analysis results in MOEs of less than 1000. 
Please see Table 2, below, for a summary of the tolerance breakdown.  (A
listing of the 144 tolerances being reassessed at this time appears in
Table A.1.  A listing of the 84 tolerances not meeting the Insignificant
Contributors criteria appears in Tables A.4 and A.5.)  EPA may require
mitigation for some of the uses associated with the 84 tolerances not
meeting the Insignificant Contributors criteria, in connection with its
completion of the outstanding IREDS and release of the revised NMC
cumulative risk assessment.  

Sixty-nine of the 80 previously-reassessed methomyl tolerances meet
EPA’s criteria for designation as ‘Insignificant Contributors’ due
to no exposure or low exposure.  (A listing of these 69 tolerances
appears in Table A.2.)  However, eleven methomyl tolerances do not meet
the ‘Insignificant Contributors’ criteria because the Agency needed
to remove them from the analysis in order to reach MOEs of greater than
1000.  (A listing of these 11 tolerances appears in Table A.3.) 
Notwithstanding the fact that the methomyl tolerances were reassessed in
connection with the 1998 methomyl RED, the Agency may require additional
mitigation for some of the methomyl uses associated with the eleven
methomyl tolerances that do not meet the ‘Insignificant
Contributors’ criteria.  The Agency will make its decision about the
necessity of mitigation in conjunction with its completion of the final
NMC cumulative risk assessment.  

The Agency notes that this is a screening-level assessment designed to
ensure that risk is not underestimated.  By selecting a
point-of-comparison value of 1000, the Agency has produced a
conservative assessment that assumes that the interspecies,
intraspecies, and FQPA factors will be assigned values of 10.  These
values are conservative because the Agency anticipates that the
interspecies and/or FQPA safety factors for some of the NMCs will be
assigned lower values in the revised NMC cumulative assessment, based on
recently-submitted data.  

Following the completion of the revised NMC cumulative risk assessment,
more tolerances are expected to be eligible for reassessment.  However,
for purposes of this screening-level analysis, the Agency has elected to
assign maximum safety factor values to ensure that risk is not
underestimated. 

Table 2.  Summary of tolerances designated as ‘Insignificant
Contributors’ compared with tolerances excluded from the assessment

Insignificant Contributors 	Tolerances Excluded from the Assessment



        144 tolerances

11 tolerances:  Crop/chemical combinations with NO detects in all years
of PDP monitoring [listed in Table A.1 as “ND”] 

27 tolerances:  Meat, milk, poultry and egg  tolerances for which
exposure is deemed negligible [listed in Table A.1 as “M”]

32 tolerances:  Livestock feed stuffs associated with the meat, milk,
poultry, and egg samples for which few, small, or no detectable residues
were found [listed in Table A.1 as “FS”]

74 tolerances: Low contributorsa to cumulative risk (i.e., MOEs of
greater than 1000 when considered together ) [listed in Table A.1 as
“LC”]  

	

84 Tolerances

62 tolerances not eligible (aldicarb and carbofuran)

52 low contributorsa

10 high contributors

62 TOTAL

23 aldicarb

39 carbofuran

62 TOTAL

[Listed  in Table A.5]

22 tolerances not eligible (high contributors)

11 carbaryl

4 formetanate HCl

7 oxamyl

22 TOTAL 

[Listed in  Table A.4]



a Low contributors are those tolerances that produce MOEs of >1000 when
the high contributors are not included in the analysis.

 

Conclusions 

	EPA has concluded that the 144 tolerances identified in this document
as Insignificant Contributors to the NMC cumulative risk meet the safety
standard of section 408(b)(2) of the FFDCA, and may therefore be
considered reassessed, pursuant to section 408(q) as of today’s date,
June 29, 2006.  

	As a result of this decision, there are 84 NMC tolerances that remain
to be reassessed.  These remaining 84 tolerances will be reassessed when
EPA completes the IREDs for aldicarb and carbofuran and issues the final
NMC cumulative risk assessment. 



APPENDIX

Table A.1 Insignificant Contributor Tolerances due to no exposure or low
exposure

Pesticide Name	Commodity Name	Reason For Insignificant Contributor
Status1

Carbaryl	Alfalfa	FS

Carbaryl	Alfalfa, Hay	FS

Carbaryl	Almonds	LC

Carbaryl	Almonds, Hulls	FS

Carbaryl	Asparagus	LC

Carbaryl	Bananas	ND

Carbaryl	Beets, Garden, Roots	LC

Carbaryl	Beets, Garden, Tops	FS

Carbaryl	Beets, Sugar	LC

Carbaryl	Blackberries	LC

Carbaryl	Blueberries	LC

Carbaryl	Boysenberries	LC

Carbaryl	Broccoli	LC

Carbaryl	Brussels Sprouts	LC

Carbaryl	Cabbage	LC

Carbaryl	Cabbage, Chinese	LC

Carbaryl	Carrots	LC

Carbaryl	Cattle, Fat	M

Carbaryl	Cattle, Kidney	M

Carbaryl	Cattle, Liver	M

Carbaryl	Cattle, Meat By Products (excluding kidney & liver)	M

Carbaryl	Cattle, Meat	M

Carbaryl	Cauliflower	ND

Carbaryl	Celery	LC

Carbaryl	Chestnuts	LC

Carbaryl	Clover	FS

Carbaryl	Clover, Hay	FS

Carbaryl	Collards	LC

Carbaryl	Corn (including sweet) (kernel + cobs w/ husks removed)	ND

Carbaryl	Corn, Fodder	FS

Carbaryl	Corn, Forage	FS

Carbaryl	Cotton, Seed	FS

Carbaryl	Cranberries	LC

Carbaryl	Cucumbers	LC

Carbaryl	Dandelions	LC

Carbaryl	Dewberries	LC

Carbaryl	Dill	LC

Carbaryl	Eggplant	LC

Carbaryl	Endive (Escarole)	LC

Carbaryl	Filberts (Hazelnuts)	LC

Carbaryl	Flax, Seed	LC

Carbaryl	Goats, Fat	M

Carbaryl	Goats, Kidney	M

Carbaryl	Goats, Liver	M

Carbaryl	Goats, Meat By Products (excluding kidney & liver)	M

Carbaryl	Goats, Meat	M

Carbaryl	Grasses	FS

Carbaryl	Grasses, Hay	FS

Carbaryl	Hogs, Fat	M

Carbaryl	Hogs, Kidney	M

Carbaryl	Hogs, Liver	M

Carbaryl	Hogs, Meat By Products	M

Carbaryl	Hogs, Meat	M

Carbaryl	Horseradish	LC

Carbaryl	Horses, Fat	M

Carbaryl	Horses, Kidney	M

Carbaryl	Horses, Liver	M

Carbaryl	Horses, Meat By Products (excluding kidney & liver)	M

Carbaryl	Horses, Meat	M

Carbaryl	Kale	LC

Carbaryl	Kohlrabi	LC

Carbaryl	Lentils	ND

Carbaryl	Lettuce	LC

Carbaryl	Loganberries	LC

Carbary	Melons	LC

Carbaryl	Milk	M

Carbaryl	Millet, Proso, Grain	FS

Carbaryl	Millet, Proso, Straw	FS

Carbaryl	Mustard, Greens	LC

Carbaryl	Okra	LC

Carbaryl	Olives	LC

Carbaryl	Oysters	M

Carbaryl	Parsley	LC

Carbaryl	Parsnips	LC

Carbaryl	Peanuts	LC

Carbaryl	Peanuts, Hay	FS

Carbaryl	Peas, Cowpeas	LC

Carbaryl	Peas, Cowpeas, Forage	FS

Carbaryl	Peas, Cowpeas, Hay	FS

Carbaryl	Peas, Vines	FS

Carbaryl	Peas, with Pods	LC

Carbaryl	Pecans	LC

Carbaryl	Pineapples	LC

Carbaryl	Pistachios	LC

Carbaryl	Potatoes	ND

Carbaryl	Prickly Pear Cactus, Fruit	LC

Carbaryl	Prickly Pear Cactus, Pads	LC

Carbaryl	Pumpkins	LC

Carbaryl	Radishes	LC

Carbaryl	Raspberries	LC

Carbaryl	Rice	LC

Carbaryl	Rice, Straw	FS

Carbaryl	Rutabagas	LC

Carbaryl	Salsify, Roots	LC

Carbaryl	Salsify, Tops	LC

Carbaryl	Sheep, Fat	M

Carbaryl	Sheep, Kidney	M

Carbaryl	Sheep, Liver	M

Carbaryl	Sheep, Meat By Products (kidney & liver)	M

Carbaryl	Sheep, Meat	M

Carbaryl	Sorghum, Forage	FS

Carbaryl	Sorghum, Grain	FS

Carbaryl	Soybeans	ND

Carbaryl	Soybeans, Forage	FS

Carbaryl	Soybeans, Hay	FS

Carbaryl	Spinach	LC

Carbaryl	Squash, Summer	LC

Carbaryl	Squash, Winter	LC

Carbaryl	Sunflower, Seeds	LC

Carbaryl	Sweet Potatoes	LC

Carbaryl	Swiss Chard	LC

Carbaryl	Tomatoes	LC

Carbaryl	Trefoil, Birdsfoot, Forage	FS

Carbaryl	Trefoil, Birdsfoot, Hay	FS

Carbaryl	Turnips, Roots	LC

Carbaryl	Turnips, Tops	FS

Carbaryl	Walnuts	LC

Carbaryl	Wheat, Fodder, Green	FS

Carbaryl	Wheat, Grain	FS

Carbaryl	Wheat, Straw	FS

Formetanate HCl	Grapefruit	LC

Formetanate HCl	Lemons	LC

Formetanate HCl	Limes	LC

Formetanate HCl	Oranges	LC

Formetanate HCl	Tangerines	LC

Oxamyl	Bananas	ND

Oxamyl	Cantaloupes	LC

Oxamyl	Citrus Fruits	LC

Oxamyl	Cotton, Seed	LC

Oxamyl	Eggplant	LC

Oxamyl	Honeydew	LC

Oxamyl	Peanuts	LC

Oxamyl	Peanuts, Hay	FS

Oxamyl	Peppermint, Hay	FS

Oxamyl	Peppers, Non-Bell	LC

Oxamyl	Pineapples	ND

Oxamyl	Pineapples, Bran	FS

Oxamyl	Potatoes	ND

Oxamyl	Pumpkins	LC

Oxamyl	Soybeans	ND

Oxamyl	Spearmint, Hay	FS

Oxamyl	Squash, Winter	LC

Oxamyl	Tomatoes	LC

Oxamyl	Vegetables, Root Crop	ND

1 FS = Feed Stuff; LC = Low Contribution; M = Meat, Milk, Poultry, Eggs;
ND = No detects in PDP.

Table A.2  Previously reassessed methomyl tolerances which are
‘Insignificant Contributors’ due to no exposure or low exposure 

Pesticide Name	Commodity Name

Methomyl	Alfalfa

Methomyl	Asparagus

Methomyl	Avocados

Methomyl	Barley, grain

Methomyl	Barley, hay

Methomyl	Barley, straw

Methomyl	Beans, dry

Methomyl	Beets, Tops

Methomyl	Blueberries

Methomyl	Broccoli

Methomyl	Brussels Sprouts 

Methomyl	Cabbage, Chinese

Methomyl	Cauliflower

Methomyl	Celery

Methomyl	Collards

Methomyl	Corn, Fodder

Methomyl	Corn, Forage

Methomyl	Corn, fresh (inc sweet, kernel plus cob with husks removed)

Methomyl	Corn, grain (inc pop)

Methomyl	Cotton, seed

Methomyl	Dandelions

Methomyl	Endive (Escarole)

Methomyl	Grapefruit

Methomyl	Grasses, Bermuda

Methomyl	Grasses, Bermuda, hay (dry, dehydrated)

Methomyl	Kale

Methomyl	Leeks

Methomyl	Lemons

Methomyl	Lentils

Methomyl	Mint, hay

Methomyl	Mustard, greens

Methomyl	Nectarines

Methomyl	Oats, forage

Methomyl	Oats, grain

Methomyl	Oats, hay

Methomyl	Oats, straw

Methomyl	Onions, green

Methomyl	Parsley

Methomyl	Peanuts

Methomyl	Pears

Methomyl	Peas

Methomyl	Peas, vines

Methomyl	Pecans

Methomyl	Peppers

Methomyl	Pomegranates

Methomyl	Rye, forage

Methomyl	Rye, grain

Methomyl	Rye, straw

Methomyl	Sorghum, forage

Methomyl	Sorghum, grain

Methomyl	Soybeans

Methomyl	Soybeans, forage

Methomyl	Swiss chard

Methomyl	Tangerines

Methomyl	Turnips, greens, tops

Methomyl	Vegetables, brassica, leafy, group 5

Methomyl	Vegetables, fruiting

Methomyl	Vegetables, leafy 

Methomyl	Wheat, forage

Methomyl	Wheat, grain

Methomyl	Wheat, hay

Methomyl	Wheat, straw



Table A.3  Previously reassessed methomyl tolerances which are not
‘Insignificant Contributors’ due to high contribution to exposure  

Pesticide Name	Commodity Name

Methomyl	Apple 

Methomyl	Beans, succulent 

Methomyl	Cabbage 

Methomyl	Cucurbits 

Methomyl	Grapes 

Methomyl	Lettuce

Methomyl	Oranges 

Methomyl	Peaches

Methomyl	Spinach

Methomyl	Strawberries

Methomyl	Tomatoes



Table A.4   Tolerances which require reassessment that are not
‘Insignificant Contributors’ due to high contribution to exposure

Pesticide Name	Commodity Name

Carbaryl	Apricots

Carbaryl	Beans

Carbaryl	Cherries

Carbaryl	Citrus Fruits

Carbaryl	Fruits, Pome

Carbaryl	Grapes

Carbaryl	Nectarines

Carbaryl	Peaches

Carbaryl	Peppers

Carbaryl	Plums (fresh prunes)

Carbaryl	Strawberries

Formetanate HCl	Apples

Formetanate HCl	Nectarines

Formetanate HCl	Peaches

Formetanate HCl	Pears

Oxamyl	Apples

Oxamyl	Celery

Oxamyl	Cucumbers

Oxamyl	Pears

Oxamyl	Peppers, Bell

Oxamyl	Squash, Summer

Oxamyl	Watermelons



Table A.5   Tolerances which require reassessment that are not
‘Insignificant Contributors’ because the associated IREDs have not
been completed

Pesticide Name	High Contributor versus

Low Contributor	Commodity Name

Aldicarb	High	Grapefruit

Aldicarb	High	Oranges 

Aldicarb	High	Potatoes

Aldicarb	High	Sweet Potatoes

Aldicarb	Low	Beans, Dry

Aldicarb	Low	Beets, Sugar

Aldicarb	Low	Beets, Sugar, Tops

Aldicarb	Low	Citrus, Dried Pulp

Aldicarb	Low	Coffee Beans

Aldicarb	Low	Cotton, Seed

Aldicarb	Low	Cotton, Seed, Hulls

Aldicarb	Low	Lemons

Aldicarb	Low	Limes

Aldicarb	Low	Peanuts

Aldicarb	Low	Pecans

Aldicarb	Low	Sorghum, Grain

Aldicarb	Low	Sorghum, Bran

Aldicarb	Low	Sorghum, Bran

Aldicarb	Low	Sorghum, Grain, Fodder

Aldicarb	Low	Soybeans

Aldicarb	Low	Sugarcane

Aldicarb	Low	Sugarcane, Fodder

Aldicarb	Low	Sugarcane, Forage

Carbofuran	High	Cucumbers

Carbofuran	High	Grapes

Carbofuran	High	Melons

Carbofuran	High	Potatoes

Carbofuran	High	Raisins

Carbofuran	High	Squash

Carbofuran	Low	Alfalfa, Fresh

Carbofuran	Low	Alfalfa, Hay

Carbofuran	Low	Artichokes

Carbofuran	Low	Bananas

Carbofuran	Low	Barley, Grain

Carbofuran	Low	Barley, Straw

Carbofuran	Low	Beets, Sugar

Carbofuran	Low	Beets, Sugar, Tops

Carbofuran	Low	Coffee Beans

Carbofuran	Low	Corn, Fodder

Carbofuran	Low	Corn, Forage

Carbofuran	Low	Corn, Fresh (inc. sweet) (kernel + cob w/ husks removed)

Carbofuran	Low	Corn, Grain (including popcorn)

Carbofuran	Low	Cotton, Seed

Carbofuran	Low	Cranberries

Carbofuran	Low	Milk

Carbofuran	Low	Oats, Grain

Carbofuran	Low	Oats, Straw

Carbofuran	Low	Peppers

Carbofuran	Low	Pumpkins

Carbofuran	Low	Rice

Carbofuran	Low	Rice, Straw

Carbofuran	Low	Sorghum, Fodder

Carbofuran	Low	Sorghum, Forage

Carbofuran	Low	Sorghum, Grain

Carbofuran	Low	Soybeans

Carbofuran	Low	Soybeans, Forage

Carbofuran	Low	Soybeans, Hay

Carbofuran	Low	Strawberries

Carbofuran	Low	Sugarcane

Carbofuran	Low	Sunflower, Seeds

Carbofuran	Low	Wheat, Grain

Carbofuran	Low	Wheat, Straw



Table A.6 Tolerances that have already been reassessed

Pesticide Name	Commodity Name

Methiocarb	Citrus Fruits

Methiocarb	Corn, field, grains

Methiocarb	Corn, fodder

Methiocarb	Corn, forage

Methiocarb	Corn (including sweet) (kernel + cobs w/ husks removed)

Methiocarb	Corn, grain (including popcorn)

Methiocarb	Peaches

Methomyl	Alfalfa

Methomyl	Apples

Methomyl	Asparagus

Methomyl	Avocados

Methomyl	Barley, grain

Methomyl	Barley, hay

Methomyl	Barley, straw

Methomyl	Beans, dry

Methomyl	Beans, succulent

Methomyl	Beets, tops

Methomyl	Blueberries

Methomyl	Brassica (Cole) Leafy Vegetables

Methomyl	Broccoli

Methomyl	Brussels sprouts

Methomyl	Cabbage

Methomyl	Cabbage, Chinese

Methomyl	Cauliflower

Methomyl	Celery

Methomyl	Collards

Methomyl	Corn, fodder

Methomyl	Corn, forage

Methomyl	Corn (including sweet) (kernel + cobs w/ husks removed)

Methomyl	Corn, Grain (including popcorn)

Methomyl	Cotton, seed

Methomyl	Cucurbits

Methomyl	Dandelions

Methomyl	Endive (escarole)

Methomyl	Grapefruit

Methomyl	Grapes

Methomyl	Grasses, bermuda

Methomyl	Grasses, bermuda, hay (dry, dehydrated)

Methomyl	Kale

Methomyl	Leeks

Methomyl	Lemons

Methomyl	Lentils

Methomyl	Lettuce

Methomyl	Mint, hay

Methomyl	Mustard, greens

Methomyl	Nectarines

Methomyl	Oats, forage

Methomyl	Oats, grain

Methomyl	Oats, hay

Methomyl	Oats, straw

Methomyl	Onions, green

Methomyl	Oranges

Methomyl	Parsley

Methomyl	Peaches

Methomyl	Peanuts

Methomyl	Pears

Methomyl	Peas

Methomyl	Peas, vines

Methomyl	Pecans

Methomyl	Peppers

Methomyl	Pomegranates

Methomyl	Rye, forage

Methomyl	Rye, grain

Methomyl	Rye, straw

Methomyl	Sorghum, forage

Methomyl	Sorghum, grain

Methomyl	Soybeans

Methomyl	Soybeans, forage

Methomyl	Spinach

Methomyl	Strawberries

Methomyl	Swiss Chard

Methomyl	Tangerines

Methomyl	Tomatoes

Methomyl	Turnips, greens, tops

Methomyl	Vegetables, fruiting

Methomyl	Vegetables, leafy

Methomyl	Wheat, forage

Methomyl	Wheat, grain

Methomyl	Wheat, hay

Methomyl	Wheat,straw

Methomyl	Barley, Forage

Methomyl	Beans, Forage

Methomyl	Hops, Dried

Methomyl	Peanuts, Hulls

Methomyl	Rye, Hay

Methomyl	Vegetables, Root Crop

Methomyl	Watercress

Thiodicarb	Corn (including sweet) (kernel + cobs w/ husks removed)

Thiodicarb	Cotton, seed

Thiodicarb	Soybeans

Thiodicarb	Soybeans, hulls

Thiodicarb	Cotton, seed, hulls



 63 Federal Register 57067, October 26, 1998.

  In some cases, a crop/pesticide combination is really a crop
group/pesticide combination if the tolerance is applicable to a crop
group.  For example, if a tolerance were established for a given
pesticide on citrus fruits, this would be considered a single crop
(group)/pesticide combination despite the fact that the tolerance
applies to all crops in that crop group (e.g., oranges, grapefruits,
lemons, limes, etc.)

 The key differences between the food files used in the August 2005
preliminary NMC cumulative risk assessment and those used in the
Insignificant Contributors analysis are: (1) PDP residues were updated
to include the most recent PDP data (through 2004) including additional
data on methomyl on strawberries; (2) processing factors were updated to
account for new food forms that appeared in the new PDP data; and (3)
aldicarb data on potatoes was modified by deleting the pre-1996 aldicarb
data on potatoes.  The deletion of pre-1996 aldicarb data is appropriate
because the use of aldicarb on potatoes was voluntarily suspended in
1990.  The use was reinstated in 1995.  Accordingly, PDP data beginning
in 1996 is most appropriate to reflect current aldicarb use on potatoes.

 OPP/HED SOP 99.3.  Memorandum from Margaret Stasikowski, Health Effects
Division to Staff.  “Translation of Monitoring Data.” HED Standard
Operating Procedure 99.3 (3/26/99), USEPA.

 Three NMCs are not included in the legend – propoxur, thiodicarb, and
pirimicarb.  These pesticides were either not detected in the PDP data
or were detected at such low concentrations and frequencies that they
are not sufficient contributors to appear on the graph.  

  Human studies for aldicarb, methomyl, and oxamyl were reviewed by the
Human Studies Review Board (HSRB) in April, 2006 and determined to be
appropriate for use in the NMC Cumulative Risk Assessment.  At the May,
2006 meeting of the HSRB, the board did not support the use of the
carbofuran oral human study for informing the inter-species factor. 

  Comparative cholinesterase studies in adult and juvenile rats are
available for carbofuran, formetanate HCl, methomyl, and oxamyl which
evaluate peak and time course brain ChE inhibition.  A dose-response
study with adult and juvenile rats exposed at peak time of effect is
available for aldicarb.

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