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The bed bug, ( Cimex lectularius L.), is a difficult pest to control. Prevalence of insecticide resistance among bed bug populations and concerns over human-insecticide exposure has stimulated the development of alternative bed bug control materials. Many essential oil-based pesticides and detergent insecticides targeting bed bugs have been developed in recent years. We evaluated the efficacy of nine essential oil-based products and two detergents using direct spray and residual contact bioassays in the laboratory. Two conventional insecticides, Temprid SC (imidacloprid and β-cyfluthrin) and Demand CS (λ-cyhalothrin), were used for comparison. Among the 11 nonsynthetic insecticides tested, only EcoRaider (1% geraniol, 1% cedar extract, and 2% sodium lauryl sulfate) and Bed Bug Patrol (0.003% clove oil, 1% peppermint oil, and 1.3% sodium lauryl sulfate) caused >90% mortality of nymphs in direct spray and forced exposure residual assays. However, the efficacy of EcoRaider and Bed Bug Patrol was significantly lower than that of Temprid SC and Demand CS in choice exposure residual bioassay. Direct spray of EcoRaider caused 87% egg mortality, whereas the other nonsynthetic insecticides had little effect on bed bug eggs. EcoRaider and Bed Bug Patrol did not exhibit detectable repellency against bed bugs in the presence of a carbon dioxide source. These findings suggest that EcoRaider and Bed Bug Patrol are potentially useful pesticides for controlling bed bug infestations, but further testing in naturally infested environments is needed.
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HOUSEHOLD AND STRUCTURAL INSECTS
Potential of Essential Oil-Based Pesticides and Detergents for
Bed Bug Control
NARINDERPAL SINGH, CHANGLU WANG,
1
AND RICHARD COOPER
Department of Entomology, Rutgers University, 93 Lipman Drive, New Brunswick, NJ 08901
J. Econ. Entomol. 107(6): 000Ð000 (2014); DOI: http://dx.doi.org/10.1603/EC14328
ABSTRACT The bed bug, (Cimex lectularius L.), is a difÞcult pest to control. Prevalence of
insecticide resistance among bed bug populations and concerns over human-insecticide exposure has
stimulated the development of alternative bed bug control materials. Many essential oil-based pes-
ticides and detergent insecticides targeting bed bugs have been developed in recent years. We
evaluated the efÞcacy of nine essential oil-based products and two detergents using direct spray and
residual contact bioassays in the laboratory. Two conventional insecticides, Temprid SC (imidacloprid
and
-cyßuthrin) and Demand CS (
-cyhalothrin), were used for comparison. Among the 11 non-
synthetic insecticides tested, only EcoRaider (1% geraniol, 1% cedar extract, and 2% sodium lauryl
sulfate) and Bed Bug Patrol (0.003% clove oil, 1% peppermint oil, and 1.3% sodium lauryl sulfate)
caused 90% mortality of nymphs in direct spray and forced exposure residual assays. However, the
efÞcacy of EcoRaider and Bed Bug Patrol was signiÞcantly lower than that of Temprid SC and Demand
CS in choice exposure residual bioassay. Direct spray of EcoRaider caused 87% egg mortality, whereas
the other nonsynthetic insecticides had little effect on bed bug eggs. EcoRaider and Bed Bug Patrol
did not exhibit detectable repellency against bed bugs in the presence of a carbon dioxide source.
These Þndings suggest that EcoRaider and Bed Bug Patrol are potentially useful pesticides for
controlling bed bug infestations, but further testing in naturally infested environments is needed.
KEY WORDS bed bug, essential oil, efÞcacy, repellency
The bed bug (Cimex lectularius L.) is a difÞcult urban
pest to control. Despite many control materials and
methods being available for bed bug management,
insecticide treatments continue to be the most pop-
ular (Moore and Miller 2008, Potter 2008, Potter et al.
2013). Many new insecticide products for bed bug
control have become available in recent years. Pyre-
throid insecticides and combinations of pyrethroids
and other classes of insecticides are routinely used by
professionals. Hot Shot Bed Bug & Flea aerosol
(0.005%
-cyhalothrin and 0.025% prallethrin) and
ready-to-use liquid spray (0.03%
-cyhalothrin) are
commonly used consumer products based on our sur-
veys in bed bug-infested apartments (N. S., unpub-
lished data). These and other sprays that use pyre-
throids as active ingredients are not very effective in
eradicating bed bugs due to insecticide resistance
among bed bug populations (Potter 2005; Romero et
al. 2007; Zhu et al. 2010, 2013). There are also general
concerns of human-insecticide exposure, as these pes-
ticides are typically applied onto furniture or around
sleeping and resting areas.
Over the past 5 yr, reduced riskbed bug control
materials have been actively sought to meet the urgent
need for do-it-yourself bed bug eradication. These
reduced risk pesticides pose less risk to human health
and the environment than existing conventional al-
ternatives. One group of materials that received par-
ticular attention is essential oils. There have been
numerous studies examining the potential of essential
oils for controlling pests of public health importance
(Barcay 2004, Isman and Machial 2006). Among them,
thymol (Pandey et al. 2009, Phillips et al. 2010), trans-
cinnamaldehyde (Cheng et al. 2008, Phillips et al.
2010), citronella oil, citral, geraniol, methyl eugenol,
eugenol (clove oil) (Cornelius et al. 1997, Ngoh et al.
1998), citronellal, cotronellol, citronellyl (Ping 2007),
catnip oil (Chauhan and Raina 2006), and carvacrol
(Panella et al. 2005) have been shown to be efÞcacious
as direct sprays against insects of urban and medical
importance. Besides essential oils, some detergent ma-
terials were found effective against the German cock-
roach (Blattella germanica L.) (Szumlas 2002, Baldwin
and Koehler 2007), the American cockroach (Peripla-
neta americana L.) (Reza et al. 2010), and the black-
legged tick (Ixodes scapularis Say) (Allan and Patrican
1995) as direct sprays.
Essential oil-based pesticides and detergents are
attractive to both manufacturers and consumers. For
manufacturers, it is comparatively easier and less ex-
pensive to market products that are generally re-
garded as safe (GRAS), as these products are exempt
1
Corresponding author, e-mail: cwang@aesop.rutgers.edu.
0022-0493/14/0000Ð0000$04.00/0 2014 Entomological Society of America
from the normal registration requirements under
FIFRA Section 25b (U.S. Environmental Protection
Agency [US EPA] 2014). For consumers, essential oil-
based pesticides and detergents are perceived as safer to
use. Our preliminary evaluations revealed signiÞcant dis-
parities in their efÞcacy against bed bugs (Singh et al.
2013). To help determine the potential role of natural
products in bed bug management, we investigated the
efÞcacy of nine essential oil-based pesticides, two de-
tergent materials, and two conventional insecticides
against Þeld-collected bed bug populations. All of
them are readily available on the market and com-
monly used by consumers or professionals.
Materials and Methods
Insects. Two bed bug strains, Indy and Bayonne,
were collected during 2008Ð2009 from infested apart-
ments in Indiana and New Jersey, respectively. The
Indy strain and the Bayonne strain were moderately
resistant to deltamethrin in our preliminary direct
spray bioassay conducted 3 mo before this study. Both
strains suffered 40% mortality after direct spray with
deltamethrin at the highest label rate (0.06%; Suspend
SC; Bayer Environmental Science, Durham, NC). The
bed bugs were maintained in plastic containers (4.7
cm in height and 5 cm in diameter) with folded paper
as harborages at 26 1C, 40 10% relative humidity
(RH), and a photoperiod of 12:12 (L:D) h, and fed
weekly on deÞbrinated rabbit blood using a Hemotek
membrane-feeding system (Discovery Workshops,
Accrington, UK). Bugs were starved for 1 wk before
bioassays.
Pesticides. Nine essential oil-based pesticides, two
detergents, and two synthetic insecticides labeled for
bed bugs were evaluated for their efÞcacy against bed
bugs (Table 1). The products were obtained either
directly from manufacturers or from commercial distrib-
utors. Temprid SC and Demand CS were diluted to 0.15
and 0.03% with water following the label directions. For
Ecoexempt IC2, spray solution containing 3.13% Ecoex-
empt IC2 and 0.78% adjuvant (2,6,8-trimethyl-4-nony-
loxy polyethylene oxyethanol; EcoSMART Technol-
ogies Inc., Franklin, TN) was prepared using water
following the label directions. All other products were
ready-to-use sprays.
Direct Spray Bioassay. Experiment I. Initial Screen-
ing. This experiment was conducted in two separate
steps during a 1-mo period to identify the effective
products. Two essential oil-based pesticides (Green
Rest Easy and Essentria) and two detergent pesticides
(Bed Bug 911 and Eradicator) were tested in the Þrst
step. In the second step, seven essential oil-based
pesticides (Bed Bug Bully, Bed Bug Fix, Bed Bug
Patrol, Ecoexempt IC2, EcoRaider, Rest Assured, and
Stop Bugging Me), and two synthetic insecticides
(Temprid SC and Demand CS) were tested. Twenty
Indy strain large nymphs (fourthÐÞfth instars) were
placed on Þlter paper in each small plastic dish (5.5 cm
in diameter and 1.5 cm in height; Fig. 1a). They were
sprayed with a pesticide using a Potter spray tower
(Burkard ScientiÞc Ltd, Herts, UK) at the application
rate of 4.07 mg/cm
2
(1 gal/1000 feet
2
). We used this
application rate for all pesticides, as it is a standard
point of run offand allows for fair comparisons
among different pesticides. The application rate de-
scribed in product labels ranged from 0.41 to 1.0 gal/
1000 feet
2
. Bed bugs in the control group were sprayed
with water. Each treatment was replicated three
times. Bugs were immediately transferred to clean
1.5-cm-diameter screened plastic petri dishes with a
paper harborage after treatment (Fig. 1a). The petri
Table 1. A list of essential oil-based pesticides, detergents, and synthetic insecticides that were used in bioassays
No. Product trade
name Listed active ingredients Manufacturer/distributor
1 Bed Bug 911 Sodium lauryl sulfate (3%), sodium chloride (1%), and citric acid (0.2%) Bedbug 911, Brooklyn, NY
2 Bed Bug Bully Mint oil (0.25%), clove oil (0.3%), citronella oil (0.4%), and rosemary
oil (0.4%)
Optimal Chemical LLC,
Tamarac, FL
3 Bed Bug Fix 2-Phenethyl propionate (2%), geraniol (1%), cedar
oil (0.3%), eugenol (0.3%), and citronella oil (0.2%)
NuSafe Floor Solutions Inc.,
Walton, KY
4 Bed Bug Patrol Clove oil (0.003%), peppermint oil (1%), and sodium lauryl sulfate (1.3%) NatureÕs Innovation Inc.,
Buford, GA
5 Demand CS
-Cyhalothrin (9.8%) Syngenta Crop Protection Inc.,
Greensboro, NC
6 Ecoexempt IC2 Rosemary oil (10%) and peppermint oil (2%) EcoSMART Technologies Inc.,
Franklin, TN
7 EcoRaider Geraniol (1%), cedar extract (1%), and sodium lauryl sulfate (2%) Reneotech Inc., North Bergen,
NJ
8 Eradicator Sodium lauryl sulfate (1.5%), sodium chloride (0.5%), and potassium
sorbate (0.06%)
Vision Bay LLC, Norcross, GA
9 Essentria 2-Phenethyl propionate (3%), geraniol (2%), rosemary oil (1.5%), and
peppermint oil (1.5%)
Envincio LLC, Cary, NC
10 Rest Assured 2-Phenethyl propionate (2%), geraniol (1%), sodium lauryl sulfate (1%), and
eugenol (0.3%)
ES & P Global LLC, Miami, FL
11 Green Rest Easy Cinnamon oil (4%), lemongrass oil (0.3%), clove oil (0.3%), peppermint
oil (0.3%), and sodium lauryl sulfate (5%)
RMB Group LLC, Stuart, FL
12 Stop Bugging Me 2-Phenethyl propionate (3%), cinnamon oil (0.1%), eugenol (0.5%),
geraniol (0.2%), and sodium lauryl sulfate (0.5%)
Rocasuba Inc., Mashpee, MA
13 Temprid SC Imidacloprid (21%) and
-cyßuthrin (10.5%) Bayer Environmental Science,
RTP, NC
2JOURNAL OF ECONOMIC ENTOMOLOGY Vol. 107, no. 6
dishes were held in a room at 26C with 40Ð50% RH,
and a photoperiod of 12:12 (L:D) h. Mortality data
were taken at 1, 3, 5, 7, and 10 d after treatment. A bed
bug was considered dead if it was not moving or could
not right itself when it was prodded with forceps.
Experiment II. Efficacy of Five Essential Oil-Based
Pesticides and Two Synthetic Insecticides against a Sec-
ond Bed Bug Strain. The Þve most effective essential
oil-based pesticides from Experiment I and two syn-
thetic insecticides were tested against Bayonne strain
large nymphs to evaluate efÞcacy against an additional
bed bug strain. The products includedÑEcoRaider,
Bed Bug Patrol, Bed Bug Fix, Rest Assured, Bed Bug
Bully, Temprid SC, and Demand CS. All treatment
procedures were the same as Experiment I.
Experiment III. Efficacy of Five Essential Oil-based
Pesticides and Two Synthetic Insecticides against Bed
Bug Eggs. Two-day- or 3-d-old Indy strain eggs were
taken out from rearing containers. In each replication,
25Ð30 eggs along with the paper substrate were
sprayed following the same procedure as described in
Experiment I. Then the eggs along with the paper
were transferred to clean 1.5-cm-diameter screened
plastic petri dishes. The essential oil-based pesticides
and synthetic insecticides used in Experiment II were
included. Each treatment was replicated three times.
Egg hatching and mortality of the nymphs emerged
from eggs were recorded at 5, 7, 10, and 14 d after
treatment.
Dry Residue Contact Bioassay. Limited Forced Ex-
posure to Fresh Residues. The most effective essential
oil-based pesticides (EcoRaider and Bed Bug Patrol)
determined in the Direct Spray Bioassay and two syn-
thetic insecticides (Temprid SC and Demand CS)
were evaluated against Indy strain large nymphs. The
pesticides were applied to 10 cm by 10 cm cardboard
panels covered with white 100% cotton fabric at the
rate of 4.07 mg/cm
2
using a Potter spray tower. The
control panels were sprayed with water. After 1 d, bed
bugs were released onto the treated fabric and con-
Þned with a plastic ring (9 cm in diameter and 2 cm in
height) for 5 min (Fig. 1b). The bugs were then trans-
ferred to clean petri dishes following the procedures
described in Experiment I. Each treatment was rep-
licated three times. Mortality was recorded at 1, 3, 5,
7, and 10 d after exposure.
Limited Forced Exposure to Aged Residues. Fresh
dry residues of EcoRaider were found to be effective
in the previous experiment. So this experiment was
designed to determine if the aged dry residues of
EcoRaider are also effective. Cardboard panels cov-
ered with white fabric were treated following the
procedures described in previous experiment. Panels
were aged for 7 and 14 d in the laboratory at 25C
before exposing them to bed bugs. Each treatment was
replicated four times. All other procedures were sim-
ilar to that in the previous experiment.
Choice Exposure to Fresh Residues. In this bioassay,
bed bugs were able to choose to stay on treated or
untreated substrate. Two most effective essential oil-
based pesticides (EcoRaider and Bed Bug Patrol) and
two synthetic insecticides (Temprid SC and Demand
CS) were tested. A white 100% cotton fabric square
(11.5 cm by 11.5 cm) was cut into two equal halves.
Fig. 1. Experimental setup: (a) Direct spray bioassay, (b) Forced exposure bioassay, (c) Choice exposure bioassay, and
(d) Repellency of selected pesticides.
December 2014 SINGH ET AL.: NATURAL PESTICIDES FOR BED BUGS 3
One half was treated with water and the other half was
treated with a pesticide using a Potter spray tower. In
the control group, both the halves were treated with
water. Fabrics were allowed to dry overnight. The two
halves were then placed and joined lengthwise in a
plastic dish (11.5 cm in diameter and 3.75 cm in
height). Twenty Indy strain large nymphs were con-
Þned with a plastic ring (3.5 cm in diameter and 1 cm
in height) in the center of the dish between the
treated and untreated fabric (Fig. 1c). After 2 min, the
ring was removed and the bed bugs were allowed to
move freely in the dish. Each treatment was replicated
three times. Carbon dioxide (CO
2
) was released from
a 5-lb cylinder (Airgas East Inc., Piscataway, NJ) at 200
ml/min daily for2hintheroom during early dark
cycle to stimulate bed bug foraging behavior. Mortal-
ity and location of the bed bugs in each dish was
recorded at 1, 3, 5, 7, and 10 d after treatment with the
aid of a red light.
Repellency of Essential Oil-Based Pesticides. This
experiment was conducted to determine if bed bugs
avoid contacting substrates treated with selected es-
sential oil-based pesticides and a synthetic pesticide.
EcoRaider, Bed Bug Patrol, and Temprid SC were
tested. Paper surgical tape (Caring International,
Mundelein, IL) was treated with pesticides using a
Potter spray tower at 4.07 mg/cm
2
. The control tape
was treated with water. After 24 h, the tape was placed
on the exterior wall of the black Climbup Insect In-
terceptors (10 cm in diameter and 2.2 cm in height;
Susan McKnight Inc., Memphis, TN). The interior
surface of the Climbup interceptors was coated with
a light layer of ßuoropolymer resin (BioQuip prod-
ucts, Rancho Dominguez, CA) to prevent trapped bed
bugs from escaping. Plastic tray arenas (80 by 75 by
5 cm; length by width by height) with a brown paper
lined bottom were used (Fig. 1d). A layer of ßuo-
ropolymer resin was applied to inner walls of the
arenas to prevent the bugs from escaping. A wooden
stool (26.5 cm in length and 26.5 cm in width) with
four legs was placed in each arena. A Þlter paper (15
cm in diameter) was placed on the center of each
arena below the stool, and then a plastic ring (13.3 cm
in diameter and 6.4 cm in height) was placed on the
Þlter paper to conÞne the bed bugs. A piece of folded
cardboard and folded fabric was placed on the Þlter
paper to provide harborages for bed bugs. Four arenas
were placed in a nonventilated room with 25 1C
and a photoperiod of 12:12 (L:D) h. Seventy Indy
strain bed bugs (35 fourthÐÞfth instar nymphs and 35
adult males) were conÞned with a plastic ring. The
bugs were acclimated for 15 h before the start of the
experiment. Each of the four interceptors under each
stool had been treated with one of three different
pesticides or water (Fig. 1d). At 1 h after the onset of
the dark cycle, CO
2
was released from a gas cylinder
to the top of stool at 100 ml/min to stimulate bed bug
activity. The plastic ring conÞning the bugs was re-
moved at 1.5 h after dark cycle to initiate the exper-
iment. The numbers of bed bugs trapped in the in-
terceptors and those in the arenas were collected and
counted after 4 h with the aid of a red light. Most
(80%) of the bugs that were responsive to CO
2
stim-
ulation were trapped in the Climbup interceptors
within4hinourpreliminary assays.
Statistical Analysis. The Abbott (1925) formula
was used to calculate corrected mortality. Percentage
corrected mortality, percentage egg hatch and survival,
and percent trap catch values were arcsine square root
transformed to meet the assumptions of normality and
homogeneity of variances. The repeated-measures
analysis of the mortality data was done using Mixed
model (JMP 2014) to determine differences between
treatments and their interaction with time. Each
source of variation, between and within treatments
(Day and Treatment Day) was included as an effect
in the model. Replicate was included as random effect.
One-way analysis of variance was used when only one
observation period was selected to compare the treat-
ments. When the interactions were signiÞcant,
TukeyÕs HSD (
0.05) was used to separate the
means. All analyses were performed with JMP version
11 (SAS Institute 2012).
Results
Direct Spray. Experiment I. Initial Screening. There
were signiÞcant differences in bed bug mortality
among pesticides at 10 d after treatment (F25.4;
df 12, 24; P0.0001). Mortality by EcoRaider
(100.0 0.0%) and Bed Bug Patrol (92.0 6.0%) was
statistically higher than those by other essential oil-
based pesticides tested; however, both of them were
not signiÞcantly different from Temprid SC (100.0
0.0%; Fig. 2). Demand CS (78.0 4.4%) was less
effective than EcoRaider and Temprid SC. Most es-
sential oil-based pesticides and detergents including
Essentria, Green Rest Easy, Eradicator, Bed Bug 911,
Stop Bugging Me, and Ecoexempt IC2 caused 0Ð30%
mortality. The mortality in the untreated control was
10%.
Experiment II. Efficacy Against a Second Bed Bug
Strain. SigniÞcant differences in bed bug mortality
were observed among pesticides (F10.2; df 12, 28;
P0.0001). At 1 d, Temprid SC (100.0 0.0%) caused
signiÞcantly higher mortality than all other pesticides
(Fig. 3). Among the essential oil-based pesticides,
EcoRaider (82.0 4.4%) caused signiÞcantly higher
mortality than other pesticides. At 5 d, Temprid SC
(100.0 0.0%) and EcoRaider (87.8 1.7%) were
statistically similar; however, EcoRaider caused sig-
niÞcantly higher mortality than all other essential oil-
based pesticides except Bed Bug Patrol (75.8 1.7%),
which caused similar level of mortality. At 10 d, Tem-
prid SC (100.0 0.0%), EcoRaider (100.0 0.0%),
Bed Bug Patrol (98.2 1.8%), and Bed Bug Bully
(92.7 3.6%) caused similar high mortality. Temprid
SC and EcoRaider were statistically different from
Bed Bug Fix, Demand CS, and Rest Assured. The
mortality in the untreated control after 10 d was 8.3
4.4%.
Experiment III. Efficacy against Eggs. Among the
Þve tested essential oil-based pesticides, only Eco-
Raider caused high-level egg mortality at 14 d (86.7
4J
OURNAL OF ECONOMIC ENTOMOLOGY Vol. 107, no. 6
1.1%) after treatment (Fig. 4). All other pesticides
caused 17% egg mortality (F20.8; df 6, 14; P
0.0001). EcoRaider was signiÞcantly more effective
than Temprid SC (58.0 5.0%) and Demand CS
(67.4 0.5%). The nymphs hatched from eggs treated
by EcoRaider, Temprid SC, and Demand CS suffered
signiÞcantly higher mortality than those from eggs
treated by the other four essential oil-based pesticides
(F12.3; df 6, 17; P0.0003). The mean percent
egg hatch and survival of nymphs in control group
after 14 d was 97.5 0.04% and 98.2 0.8%, respec-
tively.
Dry Residue Contact Bioassay. Limited Forced Ex-
posure to Fresh Residues. The four pesticides were
signiÞcantly different in their residual efÞcacy (F
16.1; df 6, 16; P0.0001; Fig. 5). At 1 d, Temprid SC
(63.3 6.0%) caused signiÞcantly higher mortality
than that by EcoRaider (11.6 6.6%) and Bed Bug
Patrol (3.3 3.3%). At 10 d, no signiÞcant difference
was observed in mortality among Temprid SC, Eco-
Raider, and Bed Bug Patrol. The mean mortality by
Temprid SC, EcoRaider, and Bed Bug Patrol was
100.0 0.0, 93.3 6.6, and 93.3 6.6%, respectively.
There was no mortality in the untreated control. Tem-
prid SC produced signiÞcantly higher mortality than
Demand CS at 5 and 10 d after treatment.
Limited Forced Exposure to Aged Residues. Both 7
and 14 d aged dry residues of EcoRaider produced
similar level of mortality at 1, 5, and 10 d after exposure
(F1.8; df 2, 12; P0.2). The mean bed bug
Fig. 2. EfÞcacy of essential oil-based pesticides and synthetic insecticides against Indy strain nymphs in a direct spray
bioassay at 10 d after treatment. Analysis was based on arcsine square root transformed data, but actual mean values are
presented here. Means with the different letters are statistically different (P0.05, TukeyÕs HSD test).
Fig. 3. EfÞcacy of selected essential oil-based pesticides and synthetic insecticides against Bayonne strain nymphs in a
direct spray bioassay. Analysis was based on arcsine square root transformed data, but actual mean values are presented here.
Means with the different letters are statistically different (P0.05, TukeyÕs HSD test).
December 2014 SINGH ET AL.: NATURAL PESTICIDES FOR BED BUGS 5
mortality caused by 7 and 14 d aged residues of Eco-
Raider was 92.5 4.3 and 90.0 2.0% at 10 d after
exposure, respectively. There was no mortality in the
untreated control.
Choice Exposure to Fresh Residues. The pesticides
tested were signiÞcantly different in their residual
efÞcacy (F5.0; df 6, 16; P0.004). Temprid SC
caused signiÞcantly higher mortality than Demand CS
at 1, 5, and 10 d after treatment. Temprid SC and
Demand CS were signiÞcantly more effective than
EcoRaider and Bed Bug Patrol. At 10 d, the mean bed
bug mortality by Temprid SC, Demand CS, Bed Bug
Patrol, and EcoRaider was 90.0 2.9, 56.7 4.8, 10.0
2.9, and 1.7 1.7%, respectively (Fig. 6). There was no
mortality in the untreated control after 10 d.
Repellency of Essential Oil-Based Pesticides. The
mean number of bed bugs trapped in interceptors cov-
ered with Temprid SC-, Bed Bug Patrol-, EcoRaider-, and
water-treated tape were 28.1 4.2, 35.2 8.0, 21.4 7.4,
and 15.4 1.4%, respectively. They were not signiÞ-
cantly different (F2.0; df 3, 12; P0.15).
Discussion
This is the Þrst comprehensive study evaluating the
efÞcacy of essential oil-based pesticides and detergent
Fig. 4. Mortality of essential oil-based pesticide- and synthetic insecticide-treated eggs and nymphs hatched from treated
eggs at 14 d after treatment. Analysis was based on arcsine square root transformed data, but actual mean values are presented
here. Bars with different letters of the same case are signiÞcantly different (P0.05, TukeyÕs HSD test).
Fig. 5. EfÞcacy of fresh dry residues of essential oil-based pesticides and synthetic insecticides against Indy strain nymphs
in limited forced exposure bioassay. Analysis was based on arcsine square root transformed data, but actual mean values are
presented here. Means with the different letters are statistically different (P0.05, TukeyÕs HSD test).
6JOURNAL OF ECONOMIC ENTOMOLOGY Vol. 107, no. 6
products labeled for bed bug control. Most of the
evaluated natural insecticides failed to cause high
mortality (i.e., 80%) to bed bugs as a direct spray.
Nevertheless, EcoRaider and Bed Bug Patrol showed
promise as a direct spray for controlling mobile stages
of bed bugs; however, the speed of kill is much slower
than the synthetic insecticide (Temprid SC). Only
one of the tested essential oil-based products (Eco-
Raider) caused high egg mortality. EcoRaider was
more effective than Demand CS, a commonly used
pyrethroid insecticide. The moderate level of mortal-
ity caused by Demand CS is mostly likely due to
pyrethroid resistance in the bed bugs. EcoRaider aged
dry residue on fabric surface maintained high insec-
ticidal activity at 14 d. Although EcoRaider and Bed
Bug Patrol were effective in direct spray and forced
exposure bioassays (fresh and aged residues), they
were ineffective in choice exposure bioassay. Bed
bugs seemed to avoid staying on substrates treated
with essential oil-based pesticides in the absence of
host cues. However, when a host cue (CO
2
) was pres-
ent, bed bugs did not exhibit signiÞcant avoidance
behavior, implying that these products are not effec-
tive repellents for bed bugs. Therefore, essential oil-
based pesticides may be useful as a direct spray. It is
also possible that these products would be effective as
a residual spray if applied directly to bed bug harbor-
age sites where aggregation cues exist; however, ad-
ditional studies are required to investigate this.
The listed active ingredients in EcoRaider and Bed
Bug Patrol have been shown to have toxic effect
against many insect pests. Eugenol at the rates of 0.148
ml/cm
2
, 0.003 ml/43.0 cm
2
, and 10
l/g exhibited toxic
activity against the American cockroach (Ngoh et al.
1998), yellowfever mosquito, Aedes aegypti L. (Bhat-
nagar et al. 1993), and the Formosan subterranean
termite, Coptotermes formosanus Shiraki (Cornelius et
al. 1997), respectively. In a separate laboratory direct
spray bioassay, a water solution containing 10% cedar
oil and 0.78% adjuvant (2,6,8-trimethyl-4-nonyloxy
polyethylene oxyethanol) caused only 22.2 4.4%
mortality to a Þeld strain (N. S., unpublished data). The
concentrations of essential oils in EcoRaider and Bed
Bug Patrol are very low and are unlikely to be lethal to
bed bugs when used alone. Some of the active ingredi-
ents in these two products also appeared in other prod-
ucts (Bed Bug Fix, Green Rest Easy, and Essentria) that
exhibited very low efÞcacy. Other factors besides the
active ingredients must have accounted for the high
efÞcacy of some essential oil-based pesticides. Adjuvants
such as wetting agents, spreaders, stabilizers, defoamers,
stickers, and solvents may produce synergistic effects to
essential oils by improving penetration through insect
cuticle and translocation of the active ingredients within
insect body.
The efÞcacy of any pesticide can vary with the
testing method, rate of application, strain, life stage of
bed bugs, and physiological state of bed bugs. We used
a Potter spray tower to standardize the application
rate to make fair comparisons of various products. The
Potter spray tower delivers much more uniform and
Þne droplets on the treated substrates compared with
the accuracy of trigger spray bottles provided by the
manufacturers. In addition, the application rate (1
gal/1,000 feet
2
) used in all experiments is equal or
higher than the label rates of the natural pesticides
tested: Stop Bugging MeÑ0.53, Bed Bug FixÑ 0.41,
Rest AssuredÑ 0.41, and Bed Bug BullyÑ1.0 gal/1,000
feet
2
. It is reasonable to believe that when following
the product label directions, these products will likely
result in lower efÞcacy than that reported in this study.
In summary, our study demonstrated the disparities
in efÞcacy among various natural products and the
effect of testing conditions on product efÞcacy. Two
essential oil-based bed bug control products showed
high efÞcacy as a direct spray. The results were ob-
tained under ideal conditions where each bed bug was
directly sprayed or exposed to the treatments. Under
Þeld conditions, bed bugs hide in cracks, crevices,
creases, and many other places where insecticide ap-
Fig. 6. EfÞcacy of essential oil-based pesticides and synthetic insecticides against Indy strain nymphs in choice exposure
bioassay. Analysis was based on arcsine square root transformed data, but actual mean values are presented here. Means with
the different letters are statistically different (P0.05, TukeyÕs HSD test).
December 2014 SINGH ET AL.: NATURAL PESTICIDES FOR BED BUGS 7
plication may not be directly applied onto the hidden
insects. Additional studies under Þeld conditions are
warranted to determine the Þeld efÞcacy of Eco-
Raider and Bed Bug Patrol and how they can be
incorporated into a bed bug management program.
Acknowledgments
We thank Wendy Wen and Marcus Kwasek for technical
assistance. Reneotech, Inc. and Bed Bug Central provided
product samples. This is New Jersey Experiment Station
publication D-08-08117-05-13.
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8JOURNAL OF ECONOMIC ENTOMOLOGY Vol. 107, no. 6
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Para determinar la toxicidad de los liquidos comerciales disponibles para lavar trastes (Palmolive®, Dawn® y Joy®) y los liquidos limpiadores usados en la casa (409®, Fantastik®, Fantastik® Orange, Dawn® Power Dissolver y Greased Lightning®) contra las cucarachas, se realizaron varios experimentos con técnicas de aplicaciónes por rocio y de inmersion. Todas las marcas y formulaciones de liquidos para lavar trastes probadas fueron igualmente tóxicos contra los adultos de la cucaracha alemana, Blattella germanica (L.), produciendo una mortalidad de 92-100% usando una solución del liquido para lavar trastes de 1% y una mortalidad de 83-100% usando una solución de 100% del los liquidos limpiadores en aplicaciones de inmersión. La CL50 para el liquido para lavar trastes, Palmolive®, fue 0.54% contra la cucaracha alemana en aplicaciones por rocio y 0.56% en las aplicaciones de por inmersión. Las asperciones de contacto no fueron efectivas contra la cucaracha americana, Periplaneta americana (L.). Sin embargo, la inmersión en liquido para lavar trastes resulto en una CL50 de 0.24%. La mortalidad de las ninfas de la cucaracha alemana comparada con los adultos fue evaluada con aplicaciones del liquido para lavar trastes Palmolive® asperjadas de contacto y de inmersion. La mortalidad de las ninfas y adultos por inmersión fue igual con 94-100% de mortalidad en la ninfas y 97-100% de mortalidad en los adults en pruebas de liquido de lavar trastes a una concentración de 1.4%. Al sumergir las cucarachas alemanas en una solución liquido para lavar trastes, se doblaron sus abdomenes hacia arriba y burbujas de aire escaparon de sus espiraculos abdominales. Las cucarachas no pudieron mantenerse en la superficie de la solución y estas se hundieron al fondo de la recipiente entre los 30 segundos después de sumergirlas.
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The toxic and repellent properties of nine major constituents of essential oils, comprising benzene derivatives and terpenes, were evaluated against Periplaneta americana (L.). Contact and fumigant toxicities to adult females and repellency to nymphs were determined. The decreasing order of knockdown activity via contact was methyl-eugenol>isosafrole=eugenol>safrole. The killing effect via contact was in the order eugenol=methyl-eugenol=isosafrole>safrole. Fumigant toxicity was only observed for safrole and isosafrole, with safrole being the more potent. Isoeugenol and the tested terpenes had neither contact nor fumigant toxic effect. The decreasing order of repellency to nymphs was safrole>isosafrole>methyl-eugenol=α-pinene> eugenol>isoeugenol. The benzene derivatives were generally more toxic and repellent to P. americana than the terpenes. The distance of the side chain double bond from the aromatic ring and the substitution of a methoxy group to these compounds appeared to be important determinants of their toxicity and repellency. © 1998 Society of Chemical Industry
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Catnip oil derived from Nepeta cataria L. (Lamiaceae), contains two monoterpenes (Z,E-and E,Z-nepetalactone) as its major components. These and two corresponding acids, generated by hydrolysis of the nepetalactones, were tested for toxicity and as barriers for tunneling against the Formosan subterranean termite, Coptotermes formosanus Shiraki. At 40 µg/cm 2 catnip oil and the 2 nepetalactones caused 100 per cent mortality in 2 days and 1 day, respectively. At 20 µg/cm 2 only the E,Z-isomer was toxic causing 97 per cent mortality in 7 days. Once again, only the E,Z-isomer prevented termite workers to tunnel through a 60 mm glass tube filled with sand treated at 200 ppm. Although monoterpenoids have short life times, proper formulations or derivatizations could be explored to overcome this deficiency in commercial development.