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Repellency of Dettol, a Commercial Cleaning Product, Against Adult American Cockroaches Periplaneta americana (L.)

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Dettol, a commercial cleaning product was tested for its repellent action against adults of Periplaneta americana (L.). Experimental cage was constructed with pieces of polypropylene plastic material to have a finished form measuring 30×30×60cm. Two cardboard shelters (for each trial) were assembled each 10cm square by size with an opening of 1.5×1.5cm to allow for free passage. One of the shelters was treated with undiluted Dettol, the other with water (control) prior to placement in the cage. Twenty five adult roaches were released in the cage also provided with water and 50g dog biscuit at each trial. The cage was placed close to the sunlight by midday over seven days observation period and the number of roaches in and close to the shelters were recorded three times by 30 minutes interval. Similar procedure was used when applying 1:37 and 1:74 dilutions of the product. A highest mean repellency (0.00±0.00) was observed in the treated shelter (TS) with undiluted concentration while the least (13.33±1.15) was in the control shelter (CS). Similarly, repellency was extended close to the treated shelter (CTS) than close to the control shelter (CCS). However, repellency was observed to be indirectly proportional to both concentration and exposure time. The active ingredient responsible for repelling the roaches in Dettol is discussed.
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Nigerian Journal of Basic and Applied Science (2010), 18(1):130-135
ISSN 0794-5698
Repellency of Dettol, a Commercial Cleaning Product, Against Adult American
Cockroaches Periplaneta americana (L.)
*M. M. Yahaya and A. Y. Clement
Department of Biological Sciences
Usmanu Danfodiyo University, Sokoto.
[*Corresponding Author: mmyahayakhad@yahoo.co.uk]
130
ABSTRACT: Dettol, a commercial cleaning product was tested for its repellent action against adults
of Periplaneta americana (L.). Experimental cage was constructed with pieces of polypropylene
plastic material to have a finished form measuring 30×30×60cm. Two cardboard shelters (for each
trial) were assembled each 10cm square by size with an opening of 1.5×1.5cm to allow for free
passage. One of the shelters was treated with undiluted Dettol, the other with water (control) prior to
placement in the cage. Twenty five adult roaches were released in the cage also provided with water
and 50g dog biscuit at each trial. The cage was placed close to the sunlight by midday over seven days
observation period and the number of roaches in and close to the shelters were recorded three times by
30 minutes interval. Similar procedure was used when applying 1:37 and 1:74 dilutions of the product.
A highest mean repellency (0.00±0.00) was observed in the treated shelter (TS) with undiluted
concentration while the least (13.33±1.15) was in the control shelter (CS). Similarly, repellency was
extended close to the treated shelter (CTS) than close to the control shelter (CCS). However,
repellency was observed to be indirectly proportional to both concentration and exposure time. The
active ingredient responsible for repelling the roaches in Dettol is discussed.
Keywords: Repellency, Periplaneta americana, Dettol
INTRODUCTION
Cockroaches are the most abundant and
obnoxious non-biting insect pest in residential
buildings, hospitals, hostels and restaurants
(Hahn, 2003; Kutrup, 2003; Mba and Kelly,
2003). They feed indiscriminately on human
food and sewage and so have copious
opportunity to disseminate human pathogens.
When cockroaches run over food, they may
leave filth or oily liquid that has offensive and
sickening odour which ruin food or render it
unacceptable (Brenner et al., 1987). Pathogenic
bacteria including Salmonella spp, Shigella
spp, Campylobacter spp, Pseudomonas
aeruginosa and Klebsiella pneumoniae have
been isolated from cockroaches (Cotton et al.,
2000). These insects have been
epidemiologically involved in toxoplasmosis,
giardiasis, sarcocystosis, and intestinal
amoebiasis (Smith and Frenkel, 1978,
Majewska, 1986, Pai et al., 2003). Similarly,
exposure to cockroach antigens may play an
important role in asthma-related health
problems (Arruda, 2005). Recent studies
strongly associated the presence of
cockroaches and increase in the severity of
asthma symptoms in individuals who are
sensitive to cockroach allergins (Alph et al.,
2001; Arlian, 2002; Miller and Peter, 2004).
There is unprecedented increase in cockroach
population in public places and residential
apartments in North America (Rauh et al.,
2002), Asia (Dong-kyu, 1995; Ghosh and
Gayen, 2006), the Middle East (Kutrup, 2003)
and Australia (Miller and Peter, 2004). In
Nigeria, the risk to human health arising from
cockroach infestation has hitherto been
underestimated considering the dearth of
entomological and epidemiological information
available (Omudu and Eyumah, 2008).
However, greater efforts have been made over
the years to control cockroaches by using
several control measures ranging from the use
of insecticidal sprays, dusts and powders, baits
and traps, which are either directed on the
eggs, nymphs or the adult cockroaches. The
use of synthetic insecticides for controlling
insect pests has been discouraged for various
reasons. Some alternative measures like using
bio-friendly repellents against cockroaches are
highly sought for. In the present study authors
have examined the effect of Dettol, a
Nigerian Journal of Basic and Applied Science (2010), 18(1):130-135
131
commercial cleaning product on adults of
American cockroach, Periplaneta americana.
MATERIALS AND METHODS
Adult American cockroaches, Periplaneta
americana (L.) were collected from toilets and
bathrooms of human dwelling. The three (3)
batches of twenty five (25) cockroaches
collected regardless of sex were acclimated in
the laboratory for a week in boxes before used
in the experiment. Two shelters each
measuring 10×10×10cm used in each separate
experiment ware built using cardboard paper
with an opening of 1.5×1.5cm to allow for free
movement of the cockroaches in and out of the
shelters. One of these was designated as a
treated shelter (TS) whiles the other a control
(CS). The TS was treated inside with 5mL
spray of the undiluted product (Dettol) using a
small hand sprayer whiles the CS with equal
volume of water. Both were allowed to dry for
few minutes under sunlight and then were
placed in a constructed polypropylene plastic
cage measuring 30×30×60cm with a wire mesh
at the top.
Twenty five adult cockroaches were released in
the cage provided with 50g dog biscuit and
water placed at the center of the cage between
the two shelters to serve as food. The cage was
moved close to the sunlight each day by
midday in order to encourage the cockroaches
to hide in the preferred shelter through the
duration of the experiment. The number of
cockroaches in the TS as well as the CS and
close to each (close to treated shelter-CTS,
close to control shelter-CCS), were recorded
three times daily by 30 minutes interval. Two
separate dilutions of the same product; 1:37
and 1:74 were also tested against the roaches
using the above procedure. For the 1:37, one
capful (27mL) of the product was diluted in a
liter of water to attain the dilution as
recommended by the manufacturer for
household cleaning. Half capful\ L of water
was used in the case of 1:74 dilutions also
recommended for personal hygiene. Number of
days for significant repellency ware determined
by using Analysis of Variance (ANOVA) and
mean separation was based on using LSD at
5%. Moreover, percent repellency was
calculated using the following formula:
100-[100× {Nt/ (Nt+Nc)}]
Where Nt is the number of cockroaches in the
treated shelter and Nc in the control shelter.
(Steltenkamp et al., 1992)
RESULTS
Undiluted product: The repellent effect of the
undiluted product on American cockroaches
over the duration of observation was
summarized in Table 1.
Table 1: Repellency of undiluted Dettol on P. americana
Treatment
groups
(shelter)
Average number of cockroaches in successive days ± SD (Repellency in per cent)
1 2 3 4 5 6 7
TS 0.00a±0.0
(100)
0.00a±0.0
(100)
0.00a±0.00
(100)
0.00a±0.00
(100)
0.00a±0.00
(100)
0.00a±0.00
(100)
0.67a±1.2
(93.7)
CTS 2.67a±0.6
(77.1)
2.00a±0.0
(82.9)
3.33b±1.5
(76.8)
3.00b±1.0
(67.8)
3.00b±1.0
(75.0)
1.67a±0.6
(84.3)
4.00b±1.0
(73.9)
CCS 9.00b±1.0
(22.9)
11.67b±1.5
(17.1)
11.00c±1.7
(23.2)
6.33c±1.2
(32.2)
9.00c±1.0
(25.0)
9.00b±2.0
(15.7)
11.33c±0.6
(26.1)
CS 13.3b±1.2
(0.0)
11.33b±1.5
(0.0)
10.67c±0.6
(0.0)
15.67d±0.6
(0.0)
13.00d±1.7
(0.0)
14.33c±2.1
(0.0)
10.00c±1.0
(6.3)
LSD 5.17 2.03 2.43 1.54 2.11 3.15 1.80
Means followed by the same letter are not significantly different (p<0.05) CS: control shelter, TS: treated shelter, CCS: close to control shelter,
CTS: close to treated shelter
There was complete repellency for six days on
the roaches in the treated shelter (TS). On day
seven few cockroaches with a mean number of
0.67± 1.2 (93.7% repellency) were observed in
the shelter indicating that the effect has began
to lessened. More than half of the cockroaches
ware residing almost always within the control
shelter (CS), but with fluctuating means
between 15.67± 0.6 to 10.00±1.0 (zero percent-
6.3% repellency). There was a daily high
significant difference (P<0.05) for repellency
in favor of TS. This effect was extended close
Yahaya &Clement; Repellency of Dettol, a Commercial Cleaning Product, Against Adult American Cockroaches Periplaneta americana (L.)
132
to the treated shelter (CTS) than close to
control shelter (CCS). Moreover, the means of
cockroaches within CTS, though fluctuate also
(between the seven days of observation), that is
from 1.67±0.6 to 4.00±1.0 (84.3% - 73.9%
repellency), were statistically significant
(P<0.05) in every respect by comparison with
6.33±1.2 (32.2% repellency) to 9.00±2.0
(15.7% repellency) obtained within CCS.
1:37 dilution: Application of the test product in
diluted form, (recommended for household
cleaning) has also resulted in high repellency
on the cockroaches in both TS and CTS (Table
2). Although, lesser mean numbers of
cockroaches were recorded in the TS for up to
four days ranging between 1.00±1.0 to
1.33±0.6 (94.1%-92.3% repellency), the values
did not differ significantly (P˂0.05) with those
obtained around CTS where repellency was
between 83.3% in the first two days and 62.5%
on the last. For the CS and CCS, the mean
value ranges of cockroaches present were
11.67±1.5 (16.6% repellency) to 17.00±1.0
(5.6% repellency) and 4.67±0.6 (26.3%
repellency) to 8.00±1.0 (27.3% repellency)
respectively. These values were still high and
not significant (P˃0.05) in reference to TS
since the higher the mean the lesser the
repellency (Table 2).
Table 2: Repellency of diluted Dettol (1:37) on P. americana
Treatment
groups
(shelter)
Average number of cockroaches in successive days ± SD (Repellency in per cent)
1 2 3 4 5 6 7
TS 1.00a±1.0
(94.1)
1.00a±1.0
(94.4)
2.00a±0.00
(89.3)
1.33a±0.6
(92.3)
2.60a±1.2
(84.0)
2.33a±1.2
(83.4)
3.00a±0.0
(82.4)
CTS 1.67a±0.6
(79.1)
1.00a±0.0
(83.3)
1.67a±0.6
(73.7)
2.00a±1.0
(73.9)
2.67a±1.2
(68.0)
3.00a±0.0
(72.7)
3.00a±1.0
(62.5)
CCS 6.33b±1.2
(20.9)
5.00b±1.7
(16.3)
4.67b±0.6
(26.3)
5.67b±0.6
(26.1)
5.67b±2.3
(32.0)
8.00b±1.0
(27.3)
5.00b±1.0
(37.5)
CS 16.00c±1.0
(5.9)
17.00c±1.0
(5.6)
16.67c±1.2
(10.7)
16.00c±1.0
(7.7)
14.00b±2.0
(16.0)
11.67c±1.5
(16.6)
14.00c±1.0
(17.6)
LSD 1.80 2.11 1.30 1.22 3.26 2.03 1.33
Means followed by the same letter are not significantly different (p<0.05) CS: control shelter, TS: treated shelter, CCS: close to
control shelter, CTS: close to treated shelter
Table 3: Repellency of diluted Dettol (1:74) on P. americana
Treatment
groups
(shelter)
Average number of cockroaches in successive days ± SD (Repellency in per cent)
1 2 3 4 5 6 7
TS 1.67a±0.6
(85.7)
2.67a±0.6
(83.0)
3.33a±0.6
(73.0)
3.33a±0.6
(74.4)
3.33a±1.5
(72.3)
4.33ab±0.6
(75.0)
4.67a±1.5
(73.6)
CTS 3.38a±0.6
(74.7)
3.67a±0.0
(67.8)
3.67a±1.5
(71.0)
4.00a±1.0
(66.7)
4.33a±1.2
(66.7)
2.67a±1.2
(65.2)
4.00a±1.0
(45.4)
CCS 10.00b±1.7
(25.3)
6.33a±3.8
(32.2)
9.00b±3.5
(29.0)
8.00b±1.7
(33.3)
8.67b±1.5
(33.3)
5.00b±1.7
(34.8)
3.33a±2.5
(54.6)
CS 10.00b±2.0
(14.3)
13.00b±3.
5
(17.0)
9.00b±2.0
(27.0)
9.67b±1.5
(25.6)
8.67b±1.7
(27.7)
13.00c±1.0
(25.0)
13.00b±0.0
(26.4)
LSD 2.61 4.86 4.07 3.67 2.82 2.24 2.93
Means followed by the same letter are not significantly different (p<0.05) CS: control shelter, TS: treated shelter, CCS: close to control
shelter, CTS: close to treated shelter
1:74 dilution: When the test product was
further diluted twice (following the
manufacturers recommendation for personal
hygiene), similar pattern of observations were
made. TS and CTS maintained high repellency
with no significant differences between the two
locations, whereas CS and CCS remained
steadily preferred by the roaches and the mean
values recorded were not significant for
relatively whole seven days of observations
(Table 3). Fig. 1-3 represents daily percentages
of repellency against the roaches.
Nigerian Journal of Basic and Applied Science (2010), 18(1):130-135
133
Fig. 1: Repellency of undiluted Dettol on P.
americana
Fig. 2: Repellency of 1:37 dilution of Dettol
on P. americana
Fig. 3: Repellency of 1:74 dilution of Dettol on
P. americana
DISCUSSION
The results of the present study revealed that
Dettol, a commercial cleaning product drive
away cockroaches. This was indicated by the
product yielding significantly higher repellency
within both TS and CTS in comparison to CS
and CCS. Complete repellency (100%) was
achieved for six days in the TS while more
than 70% in the CTS with undiluted
application of the product. Similar observations
indicating 90% repellency for three days were
reported by Ho and Goh (1996) using Ajax
Expel (another cleaning product) against
female American cockroaches. Methyl
neodecanamide which is the main ingredient in
Ajax Expel had earlier on been shown to be
active repellent on cockroaches (Steltenkamp
et al., 1992). It was also noted that repellency
of Dettol decreased with dilution and time.
This fact remained true for relatively all active
compounds since physical forces such as
temperature, light; humidity, air etc. can aid
rapid diffusion or decomposition. Application
of the two separate dilutions of the product
(1:37 and 1:74) were also significant (P<0.05)
for repelling the cockroaches in TS (90-70%
repellency) and CTS (70-40% repellency) over
the seven days period of observation. In the
former (1:37 dilution) repellency was higher
than 80% for three days as also reported by Ho
and Goh (1996) with dilution of1:8 of their test
product. However, repellency of 70% for 5.7
days reported by Connors (1994) when
working with German cockroaches is at par
with that observed in the CTS though with
fluctuations between days.
One of the apparent reasons for attaining high
repellency in this study might be the
modification of the shelter set-up from 7.6cm
square (Ho and Goh, 1996) to 10cm square.
American cockroaches are larger than most
other common cockroaches, more of the
number would be presumed occupying the
preferred shelter since the space was
conveniently enough for the twenty five
American cockroaches. Therefore, there can be
no question of certain number of un-
accommodated cockroaches outside that was
unaccounted for. Likewise, chloroxylenol in
Dettol (active principle) which might also be
responsible for repellency could be more stable
in the air than methyl neodecanamide to exploit
longer period of repellency. Moreover,
American cockroaches may be simply more
predisposed to the compounds in Dettol than to
those of Ajax Expel. Reports have shown that,
cockroaches are biochemically resistant to
pyrethroid in some countries (Atkinson et al.,
1991., Jensen, 1993). Where baits have been
used over extended periods against other
animals such as rodents baits shyness has been
noted (Meeham, 1984). Incipient behavioural
resistance has been noted with baits (Silverman
and Bieman, 1993) and cockroaches certainly
can detect and may be repelled by some
insecticides (Ebeling et al., 1967). Thus, with
the recent urge for using less insecticides,
combination or alternating use of pyrethroid,
0
20
40
60
80
100
1
2
3
4
5
6
7
Days after application
TS
CTS CCS CS
.
Repellency (per cent)
20
40
60
80
100
120
3
4
5
6
7
Days after application
TS CTS
CCS
CS
R
epellency
(per cent)
0
20
40
60
80
100
1 2 3 4 5 6 7
Days after application
R
epellency
(per cent)
TS
CTS
CCS
CS
Yahaya &Clement; Repellency of Dettol, a Commercial Cleaning Product, Against Adult American Cockroaches Periplaneta americana (L.)
134
Dettol and possibly other cleaning products
with comparable potentials, present
possibilities of managing both behavioural and
biochemical resistance. Further laboratory and
field studies should investigate the potential of
these combinations.
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... Reinfestation occurs from outdoors in warm areas, or along heating ducts and water pipes in apartments, or from groceries or luggage brought from cockroach infested areas. IPM approach for the elimination of cockroaches in homes should rely on ''change the situation that promotes cockroaches'' which highlights the reduction of food and water sources which can be done by practicing proper housekeeping including sanitation measure, exclusion and removal of hiding places, the use of baits and insecticides to reduce the infestation level and monitor the population (Adeleke et al., 2012;Yahaya and Clement, 2010). Cockroaches may even sometimes be found in very clean houses, but are unlikely to establish colonies. ...
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