EPA-AA-IMS/80-6
Evaluation Of Applicability Of A
Lead-Sensitive Test Paper As
A Diagnostic Tool For Detecting
Habitual Misfueling Of Catalyst-Equipped
Motor Vehicles
July 1980
Bill Srauda
NOTICE
Technical Reports do not necessarily represent final EPA decisions or posi-
tions. They are intended to present technical analysis of issues using data
which are currently available. The purpose in the release of such reports
is to facilitate the exchange of technical information and to inform the
public of technical developments which may form the basis for a final EPA
decision, position or regulatory action.
Inspection/Maintenance Staff
Emission Control Technology Division
Office of Air, Noise, and Radiation
U.S, Environmental Protection Agency
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Use of leaded fuel in a catalytic converter equipped vehicle (misfueling)
adversely affects the ability of the catalyst to reduce undesirable emission
levels through poisoning of the catalytic material. A quick reliable method
of detecting habitual misfueling would be a valuable diagnostic tool for
detecting lead poisoned catalysts. PLUMBTESMO is a lead sensitive test
paper that according to its manufacturer's product literature can be used to
detect metallic lead. When applied to the inside surface of a tailpipe
containing lead deposits, the originally white test paper develops red spots
and streaks within a few minutes. This test can be applied to cold or hot
tailpipes. The reaction appears to take place in less time when the tail-
pipe is hot.
The I/M staff has conducted an evaluation of PLUMBTESMO on a sample of
vehicles in the Ann Arbor area. A survey form (Attachment 1) requesting
information concerning vehicle identification and fueling habits was com-
pleted by the vehicle owners prior to testing. Seventy vehicles were tested
on two afternoons in July 1980. A PLUMBTESMO test paper was applied to each
vehicle's tailpipe, allowed approximately five minutes to react, and then
removed. A determination was made concerning color change as soon as the
test paper was removed from the vehicle. The results of this survey are
tabulated in Table 1.
The method of application of PLUMBTESMO is as follows:
1) The tailpipe was degreased by spraying a solvent (trichloroethy-
lene) into the tailpipe. A common household pump sprayer was used. It
was found necessary to degrease the tailpipe in order to wash away soot
deposits which might mask the color change.
2) The PLUMBTESMO was moistened with distilled water. A common house-
hold sprayer was used for this also. Some care roust be taken not to
overly wet the test paper. Over wetting may wash the reactive chemical
from the paper.
3) After allowing several seconds for the solvent to evaporate from
the surface of the tailpipe the test paper was placed in the tailpipe
and clamped in position with a spring-loaded wood clothespin.
4) After approximately 5 minutes the test paper was removed and the
result was observed.
The . PLUM.BTESMO exhibited a definite color change when applied to vehicles
whose owners reported regular use of leaded fuel. The vehicles certified
for use on leaded fuel are assumed to simulate habitual misfueling of cars
certified for use on unleaded fuel. In some cases a slight red color was
observed on the test paper that was applied to vehicles required and claimed
by their owners to use unleaded fuel. This coloration is attributable to
contamination rather then to the presence of lead in the tailpipe. When
plumbtesmo-is applied to a tailpipe with a large quantity of lead deposits
the reaction is vigorous. Some of the reacting chemicals were transferred
to the wood clothespins and the technician's fingers and then transferred to
the next test paper. Since approximately one-half of the vehicles in the
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sample used leaded fuel the potential for contamination was large. To avoid
this contamination careful handling of the test paper is required. This may
be accomplished by discarding any clothespins used in a positive reaction or
using a cleanable plastic clamp and using disposable wood sticks to apply
and remove the test'paper. Further, only vehicles requiring the use of
unleaded fuel should be tested in any full scale program.
The test results show no errors of commission and three apparent errocs of
omission. Comments on the survey sheets indicate that these are three cases
of casual misfueling. Vehicle owner comments reported on these survey
sheets are:
1) Used leaded fuel for about the first 5,000 miles then used unleaded
for A'0,000 miles.
2) Used two tankfuls of leaded in 44,000 miles.
3) Occasional use of leaded over a year ago.
A research publication by General Motors research laboratories, "Evaluation
of Methods for Detecting Lead in Vehicle Tailpipe Deposits" (GMR-3170J also
reports excellent results using PLUMBTESMO. GM also reports, in this pub-
lication, positive tests after only one tankful of leaded gasoline.
Based on the experience gained in this evaluation the use of PLUMBTESMO
appears to be a viable short test for detecting habitual misfueling. The
test results can be obtained within five minutes when applied to a cold
tailpipe. When the tailpipe is warm (as it would be in an I/M test lane)
the test results can be obtained much quicker. Further testing will be
required to evaluate the effectiveness of Plumbtesmo as an indicator of
casual misfueling.
The lead-sensitive test paper PLUMBTESMO is distributed by Gallard-
Schlesinger Chemical Manufacturing Corporation, Carle Place, NY. A box of
40 test papers (40x25mm) sells for $16.30. The .product literature accom-
panying the test papers is reproduced at the end of. this report (Attachment
2).
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TABLE 1
TEST RESULTS
VEHICLES WITH "USE UNLEADED FUEL ONLY"
LABELS AND OWNERS REPORTS:
Test Test
Positive Negative
(Lead) (No Lead)
Unleaded Use Only 0 30
Leaded Use Often 1 Q
Leaded Use Occasionally 1 i
Don't Know 0 1
VEHICLES WITHOUT FUEL LABELS AND . .
OWNERS REPORTS:
Unleaded Use Only . 0 4
Leaded Use Often 29 0
Leaded Use Occasionally . 0 2*
Don't Know 1 0
* Errors of Omission
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ATTACHMENT 1
In order to correlate*the results of the parking lot survey to actual use of
leaded and unleaded fuel, the following information is requested about your
vehicle.
MODEL YEAR
MAKE (Pontiac, Buick, Ford, AMC, VW, etc.)
MODEL (Grand Prix, Skylark, Mustang, Pacer, Rabbit, etc.)
COLOR
LAST THREE NUMBERS OF LICENSE PLATE
HAS LEADED (REGULAR OR LEADED PREMIUM) FUEL
BEEN USED IN THIS VEHICLE? .
IF YES, OFTEN?
YES
YES
NO DON'T KNOW
NO
Thank you for your cooperation.
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PLUMBTESMO
Test paper for the determination of lead
PLUMBTESMO determines metallic leod end lead »olh on, surfaces end In volution*.
Color reaction:
The test poper turns from light yellow —»• pink to dork red-violet.
Method of application:
o) for th» det»rmtnorton of metallic lead
Moil'en the test paper with distilled water and press firmly far two minute* agoim* the degreos*d
»>>rfoce to he tested. Substantial quantities of lead result in on immedicV reaction, whereat smaller
Cmount* of lead will only show chef teverot minutel The re»u!» should be de*efrmned within 15
mlnu'et At liHe at 0.05 «B Pb con be delected.
. b) for the determination of teod in solution*
The test poper I* rnotftrened with d»Milled water. • Lead tn exceH ofO.3gm.pef Rter will not
react with the dry paper. - The koUftion to be tested i» applied to the madefied ttn'p, or the
otfecdy moi^ened »»rip j» dipped into the jolu^on ta be tei'ed. A red color ind>cotetthe pre»ence
of lecd. The procedure permits the determinotion of lead in qjonfitiej of 0.1 gm. per lifer or more.
Leod it quantities of 03 lo 0.005 gm. per liter con be determined b/ dipping one end of o dry
PLUMBTESMO strip info the solution to be tested. After th» solution has wetted the upper
po/iio* of the strip, the appearance of o red bolder immediat^y cbo«e the le*el of the liquid
indicates the presence of lead.
Concentration* of le» thon 0.005 gtn. per liter e'e det-cted by e*>oporo:Ing o d^op of the tetT
solution on p clean g!oss slide. A red spot indicates the presence of copper, when o wefted test
poper is pressed firmly cgoins* the gtast s'ide.
Interference:
The foHowing etemenri. when preient in lorge quontiSes. inferlere wirh in* reaction: tellurium,
sitver, codmiwm, barium and Strontium, large a*nountt of nitrote-»oni reduce the sensIS-
*iV of PLUMBTESMO.
V/nen the presence of interfering catloni h suspected, they con bs eliminated (e«cep» tof
barium ond $Tro?«.'umJ thrcugS the (ollo-In; procedure: opp'y » fe*r drop! of on aqueous solution
o' 70 mg. KCN/100 ml. ws'er to the red ipofi on tSe lest paper, o-td shoVe in o micro tube
with en equal volume of 1.5 mg. ditnl/o^» in 100 ml. ecrbon te!rc:H'or»de. The green d<^izone>
co'bo.t t*t.'cchlar*de %olu>iot turns browniih-red in the presence of lecd.
MACHEREY-NAGEL • D-5160DOREN (Germany)
P.O. Box337 - Telephone (024 21) 610 71 - Tele<0333533
02/0/10.79 Printed in Germany
I
ATTACHMENT 2
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