1、Designation: E938/E938M 12Standard Test Method forEffectiveness of Liquid, Gel, Cream, or ShampooInsecticides Against Adult Human Lice1This standard is issued under the fixed designation E938/E938M; the number immediately following the designation indicates the yearof original adoption or, in the ca
2、se of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method determines the effectiveness of pedicu-licidal materials in liquid, gel,
3、or cream form, against the adulthuman louse, Pediculus humanus humanus, the surrogatesubspecies for the human head louse (P.h. capitis). (Only gelsor creams that liquefy at 32C 90F can be tested).1.2 This test method is for the use of those wishing todevelop efficacy data on adult lice.1.3 This test
4、 method consists of five replicates for a statis-tical comparison of formulations.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of
5、the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health pr
6、actices and determine the applica-bility of regulatory limitations prior to use.2. Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 morbidunable to move towards heat 1 h aftertreatment: sickly, but not necessarily dying; may recover by 24h.2.1.2 moribundunable to move towards heat
7、 (and there-fore food) 24 h after treatment; dying.3. Summary of Test Method3.1 Five replicates of 25 lice shall be used for each testconcentration or any other variable tested. Five water controlreplicates will be used on each day of testing.3.2 Percent louse mortality, corrected by Abbotts Formula
8、,is determined.24. Significance and Use4.1 This test method should provide a consistent approachboth in terms of test insects and test procedures for thegathering of efficacy data for pediculicides.4.2 Data collection in this manner should be suitable forproduct development and comparison. In additi
9、on, it should besuitable for review by regulatory agencies.5. Apparatus and Materials5.1 Test ContainerA 9-dram plastic vial, screened at thebottom with 20-mesh screen, shall be used as the dippingvessel. A plunger, made from a plastic rod, and a circularscreen fits inside the vial. Plastics used sh
10、ould be as chemicallyunreactive as possible. Plastic vials are to be discarded aftereach test.5.2 BeakersA 100- to 500-mL beaker is used to containthe pediculicide into which the test container is dipped.A1000-mL beaker is used as the container in which the lice arewashed after treatment.5.3 Heating
11、 SurfaceA slide warmer that provides heat ofapproximately 37C 98F.5.4 Incubator, capable of maintaining a temperature of31.7C 89F and 60 % RH.5.5 Petri dishes, 8.9 cm in diameter and 1.3 cm deep.5.6 Waterbath, capable of maintaining 32C 90F.1This test method is under the jurisdiction of ASTM Committ
12、ee E35 onPesticides, Antimicrobials, and Alternative Control Agents and is the directresponsibility of Subcommittee E35.12 on Insect Control Agents.Current edition approved April 1, 2012. Published May 2012. Originallyapproved in 1983. Last previous edition approved in 2011 as E938 05(2011)1.DOI: 10
13、.1520/E0938-12.2Abbott, W. S., “A Method of Computing the Effectiveness of An Insecticide,”Journal of Economic Entomology, Vol 18, 1925, pp. 265267.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesNOTICE: This standard has either been s
14、uperseded and replaced by a new version or withdrawn.Contact ASTM International (www.astm.org) for the latest information15.7 Dark Cotton Corduroy, 4by4cm.5.8 Paper Toweling, Stop Watch, Forceps or Spoon, andWash Bottle.5.9 Test InsectThe test insect is the human body louse,Pediculus humanus humanus
15、. The present strain was estab-lished from the USDA Gainesville strain.3It is a susceptiblestrain and, through selection, has adapted to a rabbit host.5.10 Host AnimalNew Zealand white rabbits.6. Rearing of Test Insects6.1 Collect eggs twice a week. This can be done when thecorduroy patches are plac
16、ed on the rabbit. The adult lice leavethe patches to feed. The patches are then removed from therabbit. Any lice that do remain on the patches should beremoved.6.2 Place the patch containing eggs in a plastic container (10by 7 cm) with a screened lid, and note the date on the container.Place the con
17、tainer in an incubator that is maintained at 31.7Cand 60 % RH.6.3 The eggs will hatch in approximately 7 days and a bloodmeal should be provided to the newly-hatched nymphs on day7.6.4 Provide blood meals six days a week. Allow the lice tofeed on the shaved abdomen of a restrained rabbit. The rabbit
18、is placed on its back on the restraining rack for approximately30 min. Collect the lice after feeding by moving the corduroypatches back and forth gently over the shaved area of therabbit. Most of the lice will attach to the patch. Pick up anyremaining lice with a forceps or a spoon.6.5 Lice used fo
19、r testing are usually 17 6 1 day old (asdetermined from the date of the first blood meal).6.6 Keep adult lice, for egg laying purposes, approximatelythree weeks (from time of hatching) and then discard.7. Procedure7.1 Place 25 adult lice, mixed sexes, in the bottom of the9-dram test container. Inser
20、t the screened plunger to keep thelice from floating to the surface.7.2 Place the pediculicide to be tested in a 100- to 500-mLbeaker and introduce the beaker into a waterbath maintained at32C. Allow the test formulation temperature to stabilize priorto testing.7.3 Place the 9-dram vial in the 100-m
21、Lpediculicide beaker,and keep the lice under the pediculicide for 10 min.7.4 Remove the test container and blot the bottom of thecontainer to remove any remaining liquid.7.5 Place the 9-dram vial into the 1000-mL beaker contain-ing tap water at 32C and agitate the container. At the end of 1min, remo
22、ve container, and gently wash the lice in a stream oftap water (32C) from the wash bottle for 1 min.7.6 Blot excess water with paper toweling.7.7 Transfer the lice to a clean 4 by 4-cm patch of darkcorduroy cloth. Use forceps to remove any lice that remain inthe container. Place corduroy patch in a
23、petri dish, then coverwith an additional corduroy patch.7.8 Place the petri dish with lice in an incubator maintainedat 31.7C and 60 % RH.7.9 Make the first observation 1 h post treatment, andreplace the petri dish in the incubator.7.10 To make an observation, place the lice on top of onepatch, whic
24、h is on top of the second patch, in a petri dish. Thepetri dish is then placed on the slide warmer (37C) or heatingpad. Lice not dead or morbid will move to the lower patchwithin 5 min.7.11 For the controls, repeat all of the above procedures,substituting tap water for the pediculicide.8. Analysis o
25、f Data8.1 Numbers of dead and moribund lice are summed to givemortality at 24 h.8.2 All mortality counts are corrected to mean correctedpercent mortality using Abbotts formula:Corrected% killed 5 % alive control 2 % alive treated!/% alive control 310038.3 Prior to statistical analysis, percent morta
26、lities will betransformed using Arcsine Tranformation Tables.4Then anAnalysis of Variance (ANOVA) will be performed and themeans will be separated by a suitable statistical procedure.9. Precision and Bias9.1 No precision data is available for this test method,however, Committee E35 is interested in
27、conducting an inter-laboratory test program and encourages interested parties tocontact the staff manager, Committee E35, ASTMHeadquarters.3The present strain of Pediculus humanus humanus is maintained by ICR, Inc.,Baltimore, MD 21228. If you are aware of alternative suppliers, please provide thisin
28、formation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.4Box, G., Hunter, W., Hunter, S., Statistics for Experimenters, Wiley, 1978.E938/E938M 122ASTM International takes no position respec
29、ting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This sta
30、ndard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Internati
31、onal Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below
32、.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).E938/E938M 123
