Insecticide Residues in Soil, Water, and Eggplant Fruits and Farmers’ Health Effects Due to Exposure to Pesticides
Environ Health Prev Med
Insecticide Residues in Soil, Water, and Eggplant Fruits and Farmers' Health Effects Due to Exposure to Pesticides
Jinky Leilanie Del Prado-Lu 0
0 J. L. Del Prado-Lu (&) Institute of Health Policy and Development Studies, National Institutes of Health, University of the Philippines Manila , NIH Bldg, P. Gil St., UP Manila, Taft Avenue, 1100 Manila , Philippines
Objectives Eggplant (Solanum melongena L.) is an important vegetable crop that is widely cultivated in the tropical and subtropical areas in Asia. Globally, the top three eggplant producers are China, India, and Egypt. The Philippines has been one of the top 10 eggplant-producing countries based on area planted and crop productivity. This study aims to describe the insecticide residues found in soil, water, and eggplant fruits in eggplant farms in Sta. Maria, Pangasinan. Methods The study design is a cross sectional of randomly selected eggplant farms in Sta. Maria, Pangasinan. Soil, water, and eggplant fruits were collected and subjected to gas chromatography (Shimadzu) analysis for multi-pesticide residues. Results Farmers from Sta. Maria, Pangasinan were found to be applying a broad spectrum of insecticides on their eggplant crop. Soil samples from 11 (about 42 %) out of the 26 farms tested positive for insecticide residues, six of which from four farms exceeded the acceptable maximum residue limit. These residues were profenofos, triazophos, chlorpyrifos, cypermethrin, and malathion. No insecticide residues were detected from water samples taken from the 26 farms. Cypermethrin and chlorpyrifos were the insecticide residues detected in eggplant fruit samples. A maximum of 20 % of the eggplant samples tested positive for insecticide residues. In the eggplant fruit study, all farmers have been using Prevathon for 24 years at a rate of 10 ml/application, and Malathion for 25 years at about 16.5 ml/application, respectively equivalent to 0.24 liter-years and 0.413 literyears of exposure. Similarly, to the findings in the soil and water study, although Brodan and Magnum were not prevalently applied, the farmers' liter-years of exposure to these insecticides, and their active ingredients, were highest at about 18.92 and 10.0, respectively. The farmers and farm workers in the soil and water study reported experiencing itchiness of the skin (63.8 %), redness of the eyes (29.3 %), muscle pains (27.6 %), and headaches (27.6 %), as being related to their pesticide exposure. Conclusion In summary, a maximum of 20 % of the eggplant samples tested positive for insecticide residues at any one stage of sampling done. The farmers and farm workers also reported of pesticide-related illnesses but none of them sought any medical attention. Intervention to reduce the farmers' pesticide exposure can focus on the risk factors identified, primarily the toxicity of pesticides used, the unsafe application practices, and the adverse health effects of pesticide exposure.
samples; Insecticide residues; Eggplant; Agriculture; Environmental; Spraying
Eggplant (Solanum melongena L.) is an important
vegetable crop that is widely cultivated in the tropical and
subtropical areas in Asia. Globally, as of 2007, the top
three eggplant producers are China with 18 million tons (t),
India with 8.5 million t, and Egypt with 1 million t. In the
same year, the Philippines was one of the top 10
eggplantproducing countries based on area planted and crop
productivity (Supplementary Table 1) [
During 2006–2011 in the Philippines, eggplant was
consistently the leading vegetable crop in terms of
production, which increased by 8.4 % from about 192,000 t in
2006 to nearly 208,000 t in 2011. In the same period, area
planted increased by 2.3 % from about 20,900 hectares
(ha) in 2006 to almost 21,400 ha in 2011, while its yield
increased by almost 6 % from 9.2 tons per hectare (t/ha) to
9.7 t/ha (BAS 2013). In 2011, the top five eggplant
producing provinces in the Philippines are Pangasinan,
Quezon, Iloilo, Isabela, and Cagayan (in this order).
Pangasinan provided almost 31 % of the country’s total
eggplant production and accounted for about 18 % of the
total area planted. However, at 17.0 t/ha, eggplant yield in
Pangasinan was only half of the yield level in Quezon
province in 2011 (Supplementary Table 2) [
Like many other crops, eggplant––from seedling to
fruiting stage––is susceptible to damage by various insects
and diseases, among which the fruit and shoot borer (FSB)
(Leucinodes orbonalis Guenee) has caused yield losses of
20–92 % in the Philippines (Francisco 2009). FSB is a
pink, sesame seed-sized moth larva that feeds on eggplant
stems and fruits from the inside out (Bleicher 2009). This
insect also bores into the terminal shoots, causing the
shoots to wither thus delaying the crop’s vegetative
To control FSB, farmers resort to frequent and heavy
spraying of insecticides. Informal interviews with eggplant
farmers in the Philippines found cases of spraying at 60–80
times during a normal fruiting duration of at least 4 months
(Francisco 2009). Similarly in India, farmers sprayed an
average of 20–30 times per crop season at about 26.7 L (li)/
ha of ‘‘cocktail’’ pesticides, such as chlorpyrifos,
cypermethrin, monocrotophos, and dimethoate [
removal of damaged fruits and shoots has proven to be
effective, yet it is rarely adopted because it is labor
However, since FSB larvae are internal feeders, control
through chemical pesticide application is often futile and
even presents high risks of environmental degradation and
contamination. The literature is rich with reports and
studies confirming that injudicious pesticide use in
agricultural crop production can pose environmental problems
such as soil and water contamination; pest tolerance or
resistance; damage to non-target organisms and
biodiversity loss; excessive chemical exposure for applicators; and
health risks for consumers.
In the present work, two studies were conducted to
determine insecticide residues first in the soil and water,
and second in eggplant fruits in Sta. Maria, Pangasinan, the
top eggplant producing province in the Philippines. More
specifically, the studies aimed to:
1. Determine the nature of insecticide residues that can be
found in the soil and water in eggplant farms, and
detect and quantify residues in eggplant fruits;
2. Determine the soil properties that influence the
persistence and mobility of insecticides in the soil and water
through literature review;
3. Differentiate insecticide residues in eggplant fruits in
three stages: farm for immature fruit prior to
harvesting, post-harvest, and market, and between two
cropping seasons (July to August for wet season, and
September to June for dry season, following the
Department of Agriculture standard);
4. Evaluate the level of insecticide residues detected in
the soil, water, and eggplant fruits against maximum
residue limits (MRLs) set by local and international
authorities [e.g., Codex Alimentarius, Environmental
Protection Agency (EPA), European Union
Commission (EC)]; and
5. Determine implications of insecticide exposure to
health of farmers/applicators and insecticide residue
in eggplants on health of consumers.
Materials and methods
The two studies were cross sectional designs of randomly
selected eggplant farms in Sta. Maria, Pangasinan,
established based on the sample size estimation equation below:
NZ2 p ð1
n ¼ Nd2 þ Z2 ½p ð1
Z is the value of the normal variable for a reliability
level, set at 90 % reliability in this study, considering
budget and feasibility;
p is the proportion of getting a positive sample based on
previous studies, set at 0.20;
1 - p is the proportion of getting a negative sample
based on previous studies, set at 0.80;
d is the sampling error, set at 0.10;
N is the population size (128 eggplant farms, as of 2010
per Municipal Agricultural Office of Sta. Maria,
n is sample size.
Source: Bautista, Victoria [
Based on the above estimation equation, 26 farms were
selected from six villages (barangays) for the soil and water
study, with a total of 58 farmers and farm workers who
participated in the health assessment aspect. The eggplant
fruit study was conducted in Sta Maria, Pangasinan with
another group of 10 farms, whose farmer-owners were
interviewed about production practices and insecticide
exposure factors. Medical doctors conducted health
profiling and assessment of the 68 farmer-respondents.
Soil and water
A total of twenty-six soil samples were collected. One field
soil sample and another replicate sample were taken from
each of the 26 farms. Each sample weighed 1 kilogram of
soil. In one farm, a final sample of soil was drawn from
well-mixed samples of soil collected at different plotting,
then placed in an opaque plastic bag, and taken for
laboratory analysis. A soil auger was used to get the soil
samples from a depth of 1 meter. The sampling standard
operating procedure recommended by the Philippine
Department of Agriculture for soil sampling is one meter
Similarly, 26 field water samples and another 26
replicate samples were taken from various sources such as river,
irrigation canal, and drinking water system located within
the 26 sample farms. There were a total of 26 samples from
all the 26 farms. There was one sample in each farm. The
replicate was used merely as a back-up sample. Each water
sample had a volume of 2 L. Two samples/replicates of the
soil and water samples and one field blank were collected
from each farm. All soil and water samples were placed in
an icebox, and delivered to the laboratory within 24 h. The
samples were stored in a laboratory refrigerator at a
temperature of 5 C, and analyzed using gas chromatography.
A total of twelve samples of 1 kg-eggplant (six 1-kg
samples per farm, two replicates) were taken from various
plotting within each of the 10 sample farms. For each farm,
each replicate group of six 1-kg eggplant samples were
mixed well together, and a final 1-kg eggplant sample was
drawn, placed in an icebox, and delivered within 24 h
which was the standard operating procedure for laboratory
analysis. In the laboratory, the samples were stored in a
freezer at a temperature of -20 C.
Sample analysis and quality control
A standard laboratory procedure was used to analyze the
material samples (BPI 2008). Briefly, the insecticide
residues were desorbed from the samples and analyzed using
gas chromatography operated in a split mode. Major
chromatogram peaks were identified in the samples by
comparing retention times and mass spectra to peaks from
a calibration method.
In the gas chromatography analysis for multi-pesticide
residues in the soil and eggplant samples, two detectors—
nitrogen phosphorous and electron capsule detectors—
were used. Solid phase extraction was done using
acetonitril. The vegetable samples underwent a three-stage
clean up to remove particulates and impurities. The first
clean up stage used C18; the second, carbon graphite; and
the third and final stage used flourisil. The water sample
underwent both liquid–liquid extraction, and one solid
phase extraction using C18 as water samples are cleaner
than soil samples. The elements in the oven program such
as the temperature programming, retention time of various
pesticides, and temperature of the detector were previously
determined and depended on each type of pesticide. The
recovery method was 70–100 %. The coefficient of
variation was less than 10 %. Two trials were done for each
sample. The limit of determination (LOD) for
organophosphates was 0.02 mg/kg, and 0.005 mg/kg for
organochlorines and pyrethroids.
The research was registered with the Research Grants
Administration Office of the National Institutes of Health,
and the Research Ethics Board stipulated that the research
study would have been exempted from ethics clearance as
it mainly focused on environmental samples and with
Results and discussion
A combined total of 36 eggplant farmers were interviewed
in the two studies: 26 farmers from barangays Samon,
Cabagbagan, Nauplasan, Cal-litang, and Pilar for the soil
and water study, and 10 farmers from the same barangays
except Cal-litang for the eggplant fruit study. All farms in
the eggplant study were included in the water and soil
The farmer-respondents in the studies reported that fruit
and shoot borer is the most common pest of eggplants in
their communities. Other pests that have been encountered
were aphids, bacterial wilt, blight, and thrips. To control
the various pests in eggplant production, farmers used
different pesticides, each of which targets a range of pests
(Supplementary Table 3). Conversely, the farmers also
used different insecticides (e.g., Brodan , Lannate ,
Malathion , Prevathon , and Tamaron ) to control fruit and
Most, if not all, farmer-respondents in the soil and water
study used Prevathon (active ingredient
chlorantraniliprole), Malathion (malathion), and Lannate (methomyl).
In terms of amount used per application, Brodan
(chlorpyrifos) came on top at 264 milliliters (ml), followed
by Siga (chlorpyrifos) at 183 ml, and Malathion at
173 ml. On average, the farmers used 77 ml of insecticide
per application. See Table 1.
Similar to the above findings, most farmer-respondents
in the eggplant fruit study used Prevathon and
Malathion , but Magnum had the highest application rate at 2
L/application, with Brodan , a distant second highest at
473 ml/application. (These application rates appear to be
outliers, as the other insecticides were used at a range of
2.5–20.0 ml/application.) If Magnum and Brodan are
included, the mean amount used per application is 235 ml;
if excluded, the mean amount used is about 12.8 ml/
application. The 26 farmer-respondents in the soil and
water study have been using pesticides for almost 9 years,
on average, while the 10 farmer-respondents in the
eggplant fruit study have been using them for nearly 23 years
(Tables 1 and 2). Looking more closely, all
farmerrespondents in the soil and water study have been using
Prevathon for about 3 years at a rate of 68 ml/application,
equivalent to 0.212 liter-years of exposure. Although
Brodan and Siga were not prevalently applied, the
farmers’ liter-years of exposure to the active ingredients of
these insecticides were highest at about 3.036 and 2.948,
respectively. See Table 2.
In the eggplant fruit study, all farmers have been
using Prevathon for 24 years at a rate of 10
ml/application, and Malathion for 25 years at about 16.5 ml/
application, respectively equivalent to 0.24 liter-years
and 0.413 liter-years of exposure. Similarly, to the
findings in the soil and water study, although Brodan
and Magnum were not prevalently applied, the farmers’
liter-years of exposure to these insecticides, and their
active ingredients, were highest at about 18.92 and 10.0,
respectively. See Table 2.
Multimedia monitoring of pesticide
Multimedia monitoring of contaminants such as
insecticides is an essential part in investigating the entire
spectrum of environmental contamination. In this study, three
media were assessed and these are the eggplant fruits, soil
samples and water samples. This is due to the fact that
pesticides can infiltrate air, oceans, rivers, groundwater,
and soil [
]. They can also move into other areas away
from sites of application, such as to water bodies through
runoff, soil through adsorption and leaching, and air
through spray/vapor drift [
]. For instance, Varca in 2002
found that, during application, only around 15 % of the
pesticides applied on crops hit the target organism; a larger
proportion is distributed in the soil and air [
]. It is the
inherent characteristics of selected insecticides and their
environmental fate in soil, water, air, and plants that
explains why this study looked into multi-media
monitoring of insecticides (Supplementary Table 4).
The fate of insecticides and their transformation
products (TPs) in the soil depend on the properties of their
active ingredients and degree of interaction with the soil
particles (or adsorption). Parameters such as water
solubility, soil-sorption constant (Koc), octanol/water partition
coefficient (Kow), and half-life of insecticides in the soil
(DT50), as well as properties such as chemical functions,
polarity, polarizability, and charge distribution of both soil
and insecticide molecules measure the persistence and
movement of insecticides and their TPs in the soil [
(Supplementary Table 5). In this study, insecticide residues
with low polar characteristics and detected in the soil
samples were chlorpyrifos, cypermethrin, malathion,
profenofos, and triazophos (Supplementary Table 5).
Insecticides vary in toxicity, persistence of active
ingredients and mobility, and thus also pose differing
degrees of environmental risks [
]. An insecticide with
low sorption coefficient, long half-life, and high water
solubility has the potential to contaminate groundwater
through leaching [
]. Half-life, the typical measure for
persistence, ranges at 10–100 days for modern pesticides.
Insecticides with longer half-lives have active ingredients
or residues that stay longer in the environment, posing
more danger to other non-target organisms [
Sediments can serve as a sink of pesticide residues,
increasing the risks of bioavailability and accumulation in
the food chain through resuspension. The soil, as the main
reservoir of pesticide residues, poses toxicity to terrestrial
and benthic organisms [
]. In California, residues of
permethrin, fenvalerate, bifenthrin, lamba-cyhalothrin were
detected in sediment samples [
]. In the Philippines,
chlorpyrifos residues were found in soil samples in
Benguet and were associated with muscle fasciculations among
the local farmers [
Insecticide residue analysis of soil and water
In general, the soil serves as a ‘‘purifying filter’’ that
influences pesticide contamination of groundwater. The
soil profile plays a significant role in determining the
chemical’s leachability to the groundwater, and soil
organic content on pesticide persistence. However, modern
technology has developed pesticides that are more
watersoluble, thermolabile, polar, and persistent, to better enable
effective pest control. These may explain why pesticide
compounds, specifically herbicides, have been detected in
surface and ground waters [
12, 13, 22, 23
Residues of five insecticides were detected in the soil of
11 farms (42 %) among the 26 sample farms. Profenofos
and triazophos were found in three and six eggplant farms,
respectively, some at levels exceeding the acceptable
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maximum residue limit (MRL) set by the European
Commission (EC) and/or the US Environmental Protection
Agency (EPA). One farm had 0.10 ppm of profenofos in
the soil, which is twice the acceptable MRL (Table 3).
Four farms had 0.02–0.05 ppm of triazophos, which is
higher than the 0.01 ppm MRL. Chlorpyrifos,
cypermethrin, and malathion were each found in two farms, although
none of them exceeded the MRL. These results have been
influenced by the insecticides’ behavior in the soil, as
indicated by their mobility, leachability, persistence, and
volatility. None of the water samples was found positive
with insecticide residues. Almost all of the insecticide
residues detected in the soil have high Koc and hence low
leaching potential. The compound’s movement is therefore
limited throughout and over the soil profile, such that there
is less potential for groundwater contamination.
In contrast, the sources of drinking water of farmers in
Southwestern part of Nigeria had been found contaminated
with diazinon and propouxr at concentrations exceeding
the acceptable daily intake (ADI) [
]. In Laguna and
Nueva Ecija provinces, both in the Philippines, residues of
pesticides including chlorpyrifos, butachlor, endosulfan,
carbofuran, methyl parathion, and monocrotrophos were
detected in groundwater samples taken from tube wells
adjacent to rice fields [
]. In this study, the deep wells
where farmers get their drinking water are possibly
contaminated with pesticide residues, because they are located
near the farms. Pesticide residues in water bodies such as
streams and rivers may affect fishes, birds, wild animals,
and plants in the aquatic habitat. Pesticides are usually
lipophilic and hydrophobic in nature, making them easily
accumulate and magnify in biological tissues of organisms
progressing up the food chain [
]. Some pesticides can
be bioaccumulated in tissues of aquatic animals, move
through the food chain, and eventually be ingested by and
adversely affect birds, wild animals and domestic
livestock. Examples are the thinning of egg shells of bald
], and reproductive depression in aquatic
biota in Dar es Salaam, Tanzania [
]. In Ghana,
pesticide residues in the farmlands along the Densu River
banks washed into the river when it rained, and
bioaccumulated in the tissues of fishes found therein [
]. In Edo
State, Nigeria, higher levels of lindane and aldrin residues
were found in fishes than in water samples [
Insecticide residue analysis of eggplant fruits
All of the farmers in the eggplant fruit study reported
applying Prevathon (chlorantraniliprole, anthranilic
diamide) and Malathion (malathion, organophosphate) to
control pests in their eggplant crops. However, farmers
used Brodan (chlorpyrifos, organophosphate) at the
highest average rate of 473 ml/application, followed by
Magnum (cypermethrin, pyrethroid) at an average of
30 ml/application. Tamaron (methamidophos,
organophosphate) was also reported as used at an average of
Of the 10 sample farms, wet season sample eggplants in
2 farms were detected as having chlorpyrifos and
cypermethrin, with the former at a level higher than the
prescribed maximum residue level (Table 4). Similarly,
cypermethrin was detected in harvested eggplants from 2
farms, with levels within the prescribed limit. From the dry
season analysis, cypermethrin was detected from samples
in 2 farms, and also from harvested eggplants in 1 farm, at
levels equal to the prescribed limit. All market samples
from both wet and dry seasons tested negative for
insecticide residues. In summary, a maximum of 20 % of the
eggplant samples tested positive for insecticide residues at
any one stage of sampling done.
Pesticide residues in plants may reach the consumers
through ingestion of raw foods [
]. Various surveys
around the world found that 50–70 % of vegetables are
contaminated with insecticide residues, which plant roots
absorbed from contaminated soils and migrated to edible
]. In Tanzania for example, Mwevura et al. [
found high levels of organochlorine pesticide residues in
edible biota in coastal areas. In India, Mukherjee and Gopal
] detected residues of fenvalerate, tau-fluvalinate,
lamba-cyhalothrin, and monocrotophos in eggplant fruits.
In the United States, endosulfan sulfate was the most
prevalent (16.76 %) pesticide residue found in eggplants,
followed by endosulfan II (12.8 %) and metamidophos
(4.5 %) [
Table 3 Summary results of
insecticide residue analysis in
the soil and water of 26 eggplant
farms, Sta. Maria, Pangasinan
a There were more than one
insecticide found in one farm
No. of samples (with
Positive for insecticide residues
Insecticide residues exceeding
Detectable concentrations of insecticide residues in soil,
water (both groundwater and surface water), air, and even
commodities pose risks to human health and the
]. A study of farming families with houses
within 200 feet from their farms detected higher
concentrations of organophosphorous pesticides (including
chlorpyrifos, parathion, phosmet, and azinphosmethyl) in
the household dust than those found in the farm soils .
In this study, the residents are potentially exposed to
household dust- and soil-contaminated insecticides since
houses are very close to the farms.
The 58 farmers and farm workers in the soil and water
study and 10 farmer-respondents in the eggplant fruit study
were interviewed on their medical history and health
profile, and a medical doctor conducted their physical health
assessment. Table 5 shows the health concerns
(complaints) that the respondents reported as related to their
application of agricultural pesticides.
The farmers and farm workers in the soil and water
study reported experiencing itchiness of the skin (63.8 %),
redness of the eyes (29.3 %), muscle pains (27.6 %), and
headaches (27.6 %), as being related to their pesticide
exposure. Meanwhile, the farmer-respondents in the
eggplant fruit study reported experiencing headaches (40 %),
itchiness of the skin (30 %), and burning sensation of the
skin (30 %). While all the respondents reported getting (or
feeling) sick immediately after applying pesticides to their
eggplant crops, none of them sought any medical attention.
The clinical manifestations of the farmer-respondents
indicate that, with complaints of mild symptoms without
obvious cholinesterase depression based on blood
chemistry, only mild pesticide poisoning has occurred. In more
severe instances, tremors, abdominal cramps, excessive
urination, bradycardia, staggering gait, pinpoint pupils, and
hypotension may be observed [
]. Significant effects of
pesticide exposure have also been reported on motor or
neuromuscular involvement, with symptoms that may
include paresthesia, convulsions, tremors, ataxia, local or
general fasciculation, and tremors [
]. Intervention to
reduce the farmers’ pesticide exposure can focus on the
risk factors identified earlier, primarily the toxicity of
pesticides used, and their unsafe application practices. All
these health symptoms have been reported in other
researchers on pesticide exposure in relation to adverse
health affectations [
Skin is the most exposed organ of the body. Farmers are
exposed to pesticides during mixing and loading the
pesticides, spraying them in the fields, as well as when
disposing empty pesticide containers and cleaning the spray
equipment. In the eggplant fruit study, the
farmer-respondents reported possibly having had dermal contact
(100 %), respiratory exposure (90 %), and ocular contact
(50 %) with the pesticides during preparation and/or field
application. Related to exposure through skin contact,
reports of pesticide-related dermatoses are recently
increasing. These include allergic or irritant contact
dermatitis, and rare clinical forms such as urticaria, erythema
multiforme, ashy dermatoses, parakeratosis variegata, and
porphyria cutanea tarda, chloracne, nail and hair disorder
]. These various routes of exposure of
insecticidesdermal, ocular, respiratory, oral- are affected by the
physicchemical characteristics of pesticides.
Across the soil and water and eggplant fruit studies covered
in this study, farmers from Sta. Maria, Pangasinan were
found to be applying a broad spectrum of insecticides on
their eggplant crop. These consisted of 25 commercial
brands, with two being category I (highly toxic) pesticides;
nine category II (moderately toxic) pesticides; and seven
each of categories III and IV (respectively, slightly toxic
and practically non-toxic) pesticides. Soil samples from 11
(about 42 %) out of the 26 farms tested positive for
insecticide residues, six of which from four farms exceeded
the acceptable maximum residue limit. No insecticide
residues were detected from water samples taken from the
26 farms. From the eggplant fruit study, residues of two
commercial insecticides were detected in the samples.
Pesticide residues can remain as environmental
pollutants in the soil, water, and even air, and impact flora and
fauna, including humans and human health. The studies’
findings suggest that environmental monitoring including
in water, groundwater, soil, air, and plants for pesticide
residues ought to be promoted and institutionalized,
especially in key agricultural production areas and
communities. Insecticide monitoring in eggplants can be done
simultaneously with soil and water monitoring since some
insecticides can leach into the soil and even groundwater.
Farmers also ought to be made better aware of the
environmental and human health impacts of pesticide use
92 % of the farmers complained of health-related problems right
after applying pesticides, including tiredness, weakness,
dizziness, nausea, vomiting, blurred vision, rashes, itchy skin,
burning sensations in the throat, chest pain, and difficulty of
Dizziness, headache, skin irritation, and burning sensation on the
face were reported by farmers in Malaysia, Ghana, Gaza strip,
and Tanzania. Eye tearing or eye redness is also common, as
well as nausea and salivation for gastrointestinal symptoms
]; Cantor and
Iishii-Eitemann and Ardhianie
Clarke et al. [
]; Nordin et al.
]; Yassin [
]; Lekei and
and exposure, and encouraged to practice more judicious
pesticide application, and to observe proper and safer
application practices. These farmer education/awareness
campaigns could be led by the municipal agriculture office,
with support from and coordination with other concerned
stakeholders, both from the public sector and the private
sector (e.g., agricultural chemical companies).
Environmental management programs can be developed and
incorporated in these campaigns to minimize, if not
neutralize, the potential adverse effects of contaminated soil,
water, and groundwater, and promote remediation practices
for contaminated such elements.
In the future, these studies could be replicated and/or
scaled up to include more farmer-respondents and/or
eggplant-producing communities/towns/provinces in the
Philippines. Such will provide a more robust set of
observations as to the variety of eggplant production
practices, extent of pesticide contamination in eggplant
production areas/environments, as well as of farmer
exposure to pesticides applied to eggplant crops. For
example, variants of these future investigations could
analyze the level of insecticide residues in eggplant fruits
according to farmer cultural pesticide application practices,
or examine the level of pesticide residues in eggplant fruits
in various stages of development up to when they are sold
retail to consumers.
Lastly, more extensive research could be conducted on
the transformation products of insecticides applied in
eggplant production in the Philippines, looking at their fate
in the soil, and the bonding forces between the soil and the
pesticide active ingredient.
Acknowledgments Acknowledgement is cited for the National
Institutes of Health, University of the Philippines Manila for its
faculty and research facilities support, and the International Service
for the Acquisition of Agri-biotech Applications for funding of this
Conflict of interest There was no conflict of interest in this study.
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