Charge to the Panel for the March 6-7, 2012 Se ssion of the FIFRA Scientific Advisory Panel (SAP) Entitled “Methods for Efficacy Testing for Bed Bug Pesticide Products”

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 EPA registered pesticide products are an important part of bed bug management programs. In the past five years pesticide users have reported control failures, which they claim is due to the lack of bed bug susceptibility to pesticide products that have been applied. Subsequently, resistance to pyrethroid insec ticides was documented although it has not been directly correlated to field app lication failures. In response, EP A has evaluated the database for registered products and concluded that there is a need to standardize approaches to bed bug product testing methods to ensure the quality and validity of the efficacy data for these types of products. In order to accomplis h this, the Agency has develo ped a draft product performance guideline for bed bug pesticide products. The Ag ency is seeking advice and recommendations from the Scientific Advisory Panel (SAP) on scie ntific issues associated with the proposed Draft Product Performance Guidelines “Laboratory Met hods for Efficacy Testing of Bed Bug Pesticide

Products.”

1) Laboratory test methods. The draft guidelines describe laboratory test methods for evaluating the efficacy of a variety of bed bug pesticide products. Please discuss:

(a) Whether, given the objectives and the types of products being evaluated, the test methods are appropriate to evaluate the efficacy of bed bug products with regard to kill and knockdown; repellency; pesticide re sistance; and discriminating dose.

(b) Whether there are additional or altern ative laboratory test methods beyond those discussed in the draft guidelines for tes ting the efficacy of bed bug pesticide products.

2) Standardized test system elemen ts and conditions (Section (h) pp. 10). The draft guidelines describe standard elements and cond itions that are recommended for each type of efficacy evaluation. Please discuss:

(a) The appropriateness of s uggested environmental conditio ns (such as temperature and humidity).

(b) The proposed test organism. In particular, please discuss:

(i) Whether the testing s hould be done only with one species, the common bed bug, Cimex lectularius . Whether it is appropriate to use unfed adult bed bugs with

a sex ratio of 1:1 to te st adultici de products.

(ii) The advantages and di sadvantages of including a su sceptible strain in every

test and whether the Harlan strain is the preferred susceptible strain.

(iii) The advantages and disa dvantages of including a resist ant strain in every test and how an investigator should select a resistant strain or strains.

(iv) The adequacy of the use of field co llected bed bug strains from urban areas in three regions of the U.S. to represent the variability in susceptibility of bed bugCharge to the Panel for the March 6-7, 2012 Se ssion of the FIFRA Scientific Advisory Panel (SAP) Entitled “Methods for Efficacy Testing for Bed Bug Pesticide Products”

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 populations for conducting efficacy evaluations.

(v) The recommended approach for groupi ng and evaluating the data from the tested bed bug strains to asse ss efficacy of bed bug products.

(c) The advantages and disadvantages of in cluding a positive cont rol in every test.

3) Specific guidance for laboratory studi es for resistant ratio determination, characterization of bed bug strain susceptibili ty, and discriminating dose selection (Section (i) pp.11). The draft guidelines propose a method to co llect the data necessary to calculate a

resistance ratio. Resistance ratios should be ca lculated for bed bug populations collected from the field in three regions in the U.S. The lethal do se values to be used in these calculations are to be derived from probit analysis. For pyrethroi d insecticides, deltamethrin is proposed as the laboratory standard. From the collected data and resistance ratio values, the procedure recommends an approach to select a discrimi nating dose for a product. Please discuss:

(a) Which insecticides should be chosen as standards for other insecticidal modes of

action.

(b) Whether it is useful to compare the resi stance ratios of bed bug field populations to the resistance ratio for a corresponding dose of deltamethrin when evaluating pyrethroid

insecticides.

(c) Whether a resistance ratio of 100x is adequate to screen field strains for resistance against insecticides and if not, what other approaches ar e recommended for detecting resistance in bed bug populations.

(d) What type(s) of data analysis and statis tical testing would be most appropriate for

these data sets.

(e) The discriminating dose selection for products, including whether the LD 90 value of the least susceptible field population is the best value to use as the basis for discriminating dose selection.

4) Exposure times to product treatments [S ections (j) (pp. 13) and (l) (pp.17)]. For residual surface and impregnated material testing, the draf t guideline proposes two possible approaches to exposing bed bugs to pesticide prod uct applications in the laborator y: 1) single dose with a fixed exposure time of 24 hours follo wed by mortality assessments through 96 hours unless all bed bugs die or control mortality exceeds 10%; and 2) single dose with an exposure time that is continuous until all bed bugs die or control mort ality exceeds 10%. The single dose is generally

the lowest label recommended dose for the product. Please discuss:

(a) Whether the exposure times provide sufficien t data to measure the efficacy of a bed bug pesticide or whether other exposure time s or testing scenarios should be used.Charge to the Panel for the March 6-7, 2012 Se ssion of the FIFRA Scientific Advisory Panel (SAP) Entitled “Methods for Efficacy Testing for Bed Bug Pesticide Products”

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 (b) Whether percent mortality values or lethal time values should be used as endpoints to assess the success of product a pplications and the advantages and disadvantages of each

one.

5) Specific guidance for laboratory studies fo r forced exposure (no-ch oice) residual surface treatment tests (Section (j) pp.13). The methods described for testing residual surface treatments recommend five type s of surfaces: unpainted plywood; linoleum tile; concrete board; cotton sheet; and medium pile carpet. Please discuss:

(a) Whether the experimental unit described in th e draft guidelines will provide sufficient data to show how effectively and how qui ckly a bed bug product knocks down and kills bed bugs, when applied as a residual treatment to surfaces.

(b) Whether there is a single surface type that could be used as a standard or representative surface for testing product resi dual activity in lieu of testing multiple

surfaces as recommended in the draft guidelines.

(c) Whether there are modifications or addi tional tests that could be recommended to improve residual surface treatment testing.

(d) What type(s) of data analysis and stat istical testing would be most appropriate for

these data sets.

6) Specific guidance for laboratory studies to de termine if bed bugs are repelled by, or attracted to, pesticide product residues (Section (k) pp. 15). For pesticide product treatments to be efficacious, bed bugs must contact pestic ide residues. Testing methods should determine whether or not pesticide residue s alter bed bug behavior, either by repellence from or attraction to pesticide treated areas. Please discuss:

(a) Whether the experimental unit described in th e draft guidelines will provide sufficient

data to measure the duration and extent to which a pesticide product’s residues repel bed bugs.

(b) Whether conditioning of experimental bed bug harborages is necessary.

(c) Whether individual responses and/or gr oup responses should be used to determine whether bed bugs are repelled by pesticid e product residues in harborages.

(d) What type(s) of data analysis and statis tical testing would be most appropriate for

these data sets.

7) Specific guidance for laboratory studies for testing pesticide impregnated material products (Section (l) pp. 17). The draft guideline proposes no -choice and choice tests forCharge to the Panel for the March 6-7, 2012 Se ssion of the FIFRA Scientific Advisory Panel (SAP) Entitled “Methods for Efficacy Testing for Bed Bug Pesticide Products”

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 treated materials. Both are to be conducted in the presence of a non- human host or artificial membrane system to provide a source of blood. The proposed tests evaluate mortality, blood feeding inhibition, and preference for treated ve rsus untreated surfaces. Please discuss:

(a) Whether the experimental unit is adequa te for evaluating mort ality and blood feeding inhibition following exposure to impregnated materials.

(b) Whether the use of an artificial membra ne system to simulate an animal host and provide blood for questing bed bugs is adequate , or whether an anim al host is necessary.

(c) Whether the assessment period is adequate.

(d) Modifications or additiona l tests that would improve pe sticide impregnated product testing.

(e) Adequacy of the experimental unit to pr ovide an experimental design and adequate data to evaluate repellency.

(f) What type(s) of data analysis and stat istical testing would be most appropriate for

these data sets.

8) Specific guidance for laboratory studies of indoor fogger produc ts (Section (m) pp.19)

. The methods described for indoor fogger testing recommend use of an experimental unit that includes a 216 cubic feet or larger Peet-Grady ch amber. The test container for bed bugs has 20 holes (1/16" diameter) in it to simulate a cr ack and crevice treatment and a bed bug refuge.

Please discuss:

(a) Whether the experimental unit is adequate for testing indoor foggers and misters.

(b) Modifications or additional tests that could be recommended to improve indoor fogger testing.

(c) What type(s) of data analysis and stat istical testing would be most appropriate for

these data sets.

9) Specific guidance for laboratory studies for testing ovicidal products (Section (o) pp. 22). Efficacious ovicidal products are likely to im prove the effectiveness of bed bug management programs. The draft guidelines describe met hods for evaluating product efficacy against eggs from direct application and contact with residua l surface applications. Please discuss:

(a) Adequacy of the experimental unit for testing ovi cidal products.

(b) Modifications or additiona l tests that could be recommended to improve ovicidal product testing.Charge to the Panel for the March 6-7, 2012 Se ssion of the FIFRA Scientific Advisory Panel (SAP) Entitled “Methods for Efficacy Testing for Bed Bug Pesticide Products”

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 (c) What type(s) of data analysis and stat istical testing would be most appropriate for

these data sets.

10) Please provide comments on the overall cl arity, accuracy and completeness of the draft guidelines: “Laboratory Testing Method s for Bed Bug Pesticide Products”. Please provide any additional comments that highlight any areas of the draft guidelines that may need to be clarified and note any relevant topics that may be missing. Pl ease include references to any published literature that could he lp improve the completeness and cl arity of the draf t guidelines.