Evaluation of pesticide residues in fruit from Poland and health risk assessment

doi:10.4236/as.2013.45B020

Paper Menu >>

Journal Menu >>

Vol.4, No.5B, 106-111 (2013) Agricultural Sciences

doi:10.4236/as.2013.45B020

Evaluation of pesticide residues in fruit from Poland

and health risk assessment

B. Łozowicka*, P. Kaczyński, E. Rutkowska, M. Jankowska, I. Hrynko

Plant Protection Institute-National Research Institute, Laboratory of Pesticide Residues, Chełmońskiego 22, Białystok 15-195, Po-

land; *Corresponding Author: [email protected]

Received 2013

ABSTRACT

In the present study an effort has been made to

evaluate the residues of insecticides, fungicides

and herbicides in fruit from Poland and their

health risks assessed. Accredited multiresidue

methods based on gas and liquid chromatog-

raphy, and spectroscopic technique were used

to determine the concentrations above 160 pes-

ticides. A total of 392 samples of 15 different

fruit were collected during the May 2010 to Oc-

tober 2012. In 48.2% of samples no residues

were found, 45.9% of samples contained pesti-

cide residues at or below the EU MRL, and 5.9%

of samples contained pesticide residues above

MRL. Sour cherries (66%) and apples (63%) were

the commodities in which pesticide residues the

most frequently occurred. Thirty one different

pesticides were detected in total. Dithiocar-

bamate, captan, cyprodinil and boscalid were

the pesticide most frequently found. Multiple

pesticides ( > 1 pesticide) were detected in about

30.1% samples. The dietary intake of residues of

some pesticides can pose acute hazards. Data

obtained were used for estimating the potential

health risks associated with the exposures to

these pesticides. The highest estimated daily

intakes (EDIs) for children were: 22% for di-

methoate and 112% for diazinone of the ADI. The

most critical commodity was apple, contributing

1.30 to the acute Hazard Index for flusilazole.

The results show that despite a high occurrence

of pesticide residues in fruit it could not be

considered a serious public health problem.

Nevertheless, an investigation into continuous

monitoring of pesticide residues in fruit is rec-

ommended.

Keywords: Pesticides; Analytical Methods; Fruit;

Poland; Risk Assessment

1. INTRODUCTION

Fruit are one of the supplementary sources of carbo-

hydrates, lipids, vitamins, minerals, antioxidants and

other important nutrients. The consumption of these

commodities with vegetables is almost 160 kg/per cap-

ita/year in Europe. A high intake of fruit has been en-

couraged not only to prevent consequences due to vita-

min deficiency but also to reduce the incidence of major

diseases such as cancer [1], cardiovascular diseases and

obesity. But fresh fruit could also be a potential source of

harmful and toxic substances. Thus, food safety has be-

come a major public concern worldwide [2].

Pesticides are chemical substances, which are com-

monly used in modern agriculture practices to protect the

crops from different pests and diseases [3]. Like other

crops, fruit are attacked by pests and diseases during

production and storage leading to damages that reduce

the quality and the yield. The use of pesticides have in-

creased because they have rapid action, decrease toxins

produced by ford infecting organisms and are less labor

intensive than other pest control methods.

However, the use of pesticides during production often

leads to the presence of pesticide residues in fruit after

harvest. Unfortunately, not all farmers follow legal prac-

tices with pesticides during production. Therefore, pesti-

cides should be controlled at optimum level due to their

relative toxicity to the human health. Pesticide residue

analysis is tremendously an important process in deter-

mining the safety of using certain pesticides. A number

of analytical methods are designed to determine multiple

pesticide residues. In the past few years, new extraction

procedures have been developed, such as solid-phase

microextraction [4] and supercritical fluid extraction [5].

Pesticides are usually determined by gas chromatography

(GC), GC-mass spectrometry, GC-ion trap mass spec-

trometry [6] and GC–tandem mass spectrometry [7].

Besides GC–MS methods, there are other traditional

quantification methods like high performance liquid

chromatography (HPLC) [8], HPLC–mass spectrometry,

low-pressure gas chromatography–mass spectrometry [9]

and liquid chromatography–tandem mass spectrometry.

B. Łozowicka et al. / Agricultural Sciences 4 (2013) 106-111 107

In our research, accredited multiresidue methods based

on gas and liquid chromatography, and spectroscopic

technique were used to determine the concentrations

above 160 pesticides.

Fruit have been given a lot of attention in monitoring

programs each country since most of them are eaten raw,

it is expected that they contain higher pesticide residue

level compared to other food groups of plant origin. Ac-

cording to the Pesticide Residues Committee in the UK,

consumers are encouraged to eat at least five portions of

fruit and vegetables daily. Poland is an important fruit,

particularly apples, exporting area in to the Europe and

Russia. Therefore, assessing the risk of pesticide residues

in these commodities intended for human consumption is

necessary.

The purpose of this paper was to present data on pesti-

cide residues in fruit from Poland carried out in 2010-

2012. Pesticide residue levels were evaluated in relation

to: Acceptable Daily Intakes (ADIs) [10] cute Reference

Doses (ARfDs) and Maximum Residue Levels (MRLs)

derived from toxicological studies. The results can be

used when designing future control programs for this

region and taking preventive actions to minimize human

health risks.

2. MATERIAL AND METHODS

2.1. Standards, Reagents and Chemicals

Pesticide reference standards were purchased from Dr.

Ehrenstorfer (Augsburg, Germany). Pesticide standard

stock solutions (purity higher than 95%) of various con-

centrations were prepared in acetone and stored in dark

below 4℃.

All solvents used were analytical grade from J.T. Baker

(Deventer, Holland), as well as florisil (60 - 100 mesh)

and phosphate buffer pH = 8. Silica gel (230 - 400 mesh),

sodium sulfide nonahydrate and celite were obtained

from Merck (Darmstadt, Germany).

2.2. Samples

A total of 392 samples of various fruit (apples – 38.8%,

strawberries – 19.1%, sour cherries – 12.8%, currants –

9.7%, pears – 6.6%, plums – 3.8%, raspberries – 3.3%,

black chokeberries – 3.1% and other – 2.8%) were col-

lected from Poland.

2.3. Analytical Procedure

Sample preparation was done using three methods:

multiresidue method (MRM) for determination of 159

pesticide residues This method was described in our pre-

viously study [11] and two single residue method (SRM)

[12,13]. Figure 1 presents all sample preparation meth-

ods and instrumental analysis used for determination

pesticide residues in fruit samples.

2.4. Quality Check

The laboratory successfully participated in the profi-

ciency testing schemes organized and run by the Euro-

pean Commission (University of Almeria) and by the

Food Analysis Performance Assessment Scheme (FAPAS;

Central Science Laboratory in York). All of the analyses

were conducted with the use of an accredited method by

the Polish Centre of Accreditation (PCA).

2.5. Method Validation

The validation of the analytical methods was carried

out in accordance with European Commission (EC)

guidelines [14]. The validation studies were performed

using pesticide-free fruit samples, previously analyzed.

Calibration standards were prepared in matrix solution to

produce a final concentration of three spiking levels

(0.005 to 0.05 mg/kg, 0.05 - 0.5 mg/kg and 0.25 - 2.5

mg/kg). Method accuracy and precision were evaluated

by performing recovery studies and are expressed as

relative standard deviation (RSD, %) and mean recovery,

respectively. Repeatability was calculated for five days

using five replicates for each level of three different

concentration levels. The sensitivity was evaluated by

determining the limit of detection (LOD) and the limit of

quantification (LOQ) of the assay. The LOD and LOQ

were calculated using the signal-to-noise ratio (S/N) cri-

teria in all cases (LOD = 3 S/N, LOQ = 10 S/N).

MSPD

159 pesticide residues

50g whole fruit 2g homogenized samples

Dithiocarbamate residuesCarbend azim residues

blending silica gel/florisil

hexane/ diethyl ether/ acetone

20g homogenized samples

SPE ChemElut/

dichloromethane

25mL acetonitrile/methanol/water hexane/acetone

Preparation

technique

Samples

Extraction/

Elution

Clean-up/

Elution

Final

extract

Instrumental

analysis GC Agilent 7890 A ECD/

NPD, HP-5 column

HPLC Waters Alliance 2695

carbendazim DAD/FLD,

λ=281nm/λex=285 nm,λem=315 nm,

Supelcosil LC-18 column

150 mL acetone

NaOH/S n Cl2 in HCl

reaction with N,N-Dimtehyl-1,4-

phenylenediammonium dichloride

Spectrophometer Helios Delta VIS

λ= 662 nm

Figure 1. Scheme of sample preparation procedures.

B. Łozowicka et al. / Agricultural Sciences 4 (2013) 106-111

108

2.6. Risk Assessment

Consumption data play a major role in the dietary risk

assessment of residues in food. This risk was calculated

through the comparison of found residues to the estab-

lished acceptable daily intake (ADI) and Acute Refer-

ences Doses (ARfD) values. The level of residue con-

centration in a product was determined as the arithmetic

mean of all the results obtained. Results under LOD of

analytical methods used for intake calculations were taken

as LOD values. Values of ADI and ARfD are elaborated

by Joint FAO/WHO Meeting on Pesticides Residues [15].

For consumer residues intake estimation were applied

new model from Pesticides Safety Directorate (PSD) of

the Department for Environment, British Food and Rural

Affairs [16]. Calculations were performed for two sub-

populations: small children (1.5 - 4 years) and adults

accepting consumption at the level of the 97.5 percentile.

The estimated daily intake (EDI) of pesticide residues

was calculated as follows:

FRL

EDI mean bodyweight



 (1)

where: Fi - food consumption data, RLi - residue level to

the commodity.

The long-term risk assessment of the intakes compared

to the pesticide toxicological data were performed by

calculating the hazard quotient (HQ), by dividing the

estimated daily intake with the relevant acceptable daily

intake:

100%

EDI

 (2)

The HQ was calculated both for pesticides and com-

modities. The HQs are summed up to give a chronic

hazard index (cHI):

cHI HQ (3)

Estimate of Short-Term Intake (ESTI) was calculated

according to the following formula:

FHRP

ESTI mean bodyweight



 (4)

where: F - full portion consumption data for the com-

modity unit, HR.P - the highest residue level.

An estimate of intake of pesticide in the diet was to

compare to the ARfD. The acute hazard index was calcu-

lated as follows:

ESTI

aHI

RfD

 (5)

3. RESULTS AND DISCUSSION

Based on our analytical studies pesticide residues were

not observed in 48.2% of fruit samples (189). Whereas

pesticide residues were found in 203 samples (51.8%). In

most of analysed samples (45.9%) pesticide residues

were below MRLs, while in 5.9% (23) above safety lim-

its (MRLs). Pesticide residue levels were compared to

EU-MRLs [17].

3.1. Multiresidue Samples

Samples containing one (21.7%), as well as multiple

active substances: two, three and even seven residues

presents Figure 2.

Most commonly detected were combination of two

pesticides: flusilzole/dithiocarbamates, captan/dithiocar-

bamates and cyprodinil/fludioxonil.

3.2. Detected Groups of Pesticides

As present Figure 3 the most occurrence group was

fungicides (81.7%). The most frequently detected active

substances among them were: dithiocarbamates (104

samples) range 0.05 to 1.87 mg/kg and captan (80) range

0.01 to 2.83 mg/kg.

Chlorpiryfos (13) range 0.03 to 0.04 mg/kg,fenazaqui

n (10) range 0.02 to 0.240 mg/kg, and acetamipiryd (9)

range 0.01 to 0.03 mg/kg, were dominated among insec-

ticides.

7 residues

0.3%

6 res idues

0.3%

5 residues

0.5%

4 residues

2.6%

3 residues

8.2%

2 res idues

18.2%

witho ut re sidue s

48.2%

1 residue

21.7%

other

11.9%

Figure 2. Samples of fruit: without, with one and multiresidue

pesticides.

020406080100 120

Number of samples

azoxystrobin 0.3%

carbend azim 0.3%

fe narimol 0.5%

tolylf lua nid 0. 5%

ip rodione 0.7%

procymidone 0.7%

te buc ona z ole 0.7%

folp et 2.5%

fe nh ex amid 3.0%

fludioxonil 3.0%

tr ifloxy str obin 3.0%

flusilazole 4.3%

pirim e tha nil 4. 8%

boscalid 5.3%

cyprodinil 5. 6%

ca pt an 20.2%

dithiocarbamates 26.3%

Fun

icides 82%

detected compounds < or = MRLsdetected compounds > MRLsdetected forbidden compounds

02468101214

deltam eth rin 0,3%

endosul fa n 0,3%

dimethoate 0,7%

phosal one 0,7%

diazinon 0,8%

alpha-cypermethrin 1,0%

es fen valerate 1,0%

fen itrothi o n 1,3%

cypermethrin 1 , 8 %

pi rimicarb 2 ,0%

acetamiprid 2,3%

fenaz aqu in 2,5%

chlo rpyrifos 3,3%

Insecticide s 18%

Figure 3. Fungicides and insecticides detected in fruit samples.

B. Łozowicka et al. / Agricultural Sciences 4 (2013) 106-111 109

3.3. Pesticide Residues in Fruit

The highest percentage of detected pesticide residues

showed sour cherry samples (66%). Grape, chokeberry,

blackberry, elderberry, wild strawberry, rose hips and sea

sallow thorn samples were free from residues. Apples

contained 59.2% samples with residues below MRL and

3.9% above MRL. The most frequently detected pesti-

cides in apple samples were: dithiocarbamates range 0.05

to 1.87 mg/kg, captan range 0.01 to 0.06 mg/kg, piryme-

thanil range 0.01 to 0.27 mg/kg, boscalid range 0.02 to

0.26 mg/kg, trifloxystrobin 0.01 to 0.100 mg/kg, diazi-

non range 0.02 to 0.03 mg/kg, dimethoate range 0.01 to

0.03 mg/kg, flusilazole range 0.01 to 0.09 mg/kg and

phosalone range 0.01 to 0.25 mg/kg. Currant contained

21% samples with residues below MRL and 39.5%

above MRL and not authorized for use. The largest

number of active substances in these samples was de-

tected, from 3 residues to 7 residues (Figure 2). The

most frequently detected pesticide above the permissible

limits were dithiocarbamates range 0.05 to 0.85 mg/kg,

fenazaquin range 0.05 to 0.24 mg/kg, fenitrothion range

0.02 to 0.03 mg/kg, esfenwalerate range 0.02 to 0.15

mg/kg and flusilazole range 0.01 to 0.09 mg/kg. Straw-

berries contained 40% of samples with residues below

MRL and 1.3% above MRL. 17 multiresidue samples

strawberries containing from 2 to 3 pesticides were re-

corded. There were also cases where not authorized fun-

gicides were detected (procymidone and tolylfluanid).

Raspberry samples with residues below MRL contained

38.5% of samples. There were two and three multiresi-

due samples detected.

3.4. Risk of Exposure

In order to assess the risk of exposure of human health

to the pesticide residues, first of all, the individual com-

ponents of dietary intakes must be known [10], taking

into account different age groups (e.g. infants, toddlers,

school children, adults etc.), as it relates to body weight

and nutritional prevention. The assessment of chronic

(long-term) health risk of consumers connected with the

consumption of apples from north-east Poland containing

pesticide residues was conducted on the basis of avail-

able epidemiological studies done for the British. There is

a lack of full studies done for Polish consumers since these

studies only take into account general population and av-

erage consumption (50 percentile) [18], and therefore had

no practical application in the current study. Accordingly,

13 GEMS/Food Consumption Cluster Diets were devel-

oped based on FAO Food Balance Sheet data from 183

countries.

The average intake for each food item at the cluster

level was weighed by the population size of the reporting

country. The western and central parts of Europe, such as

the United Kingdom, Poland, Germany, etc., have been

classified into the same Consumption Cluster Diets E

[19].

During the assessment of the long-term consumer risk

the study assumed a cautious approach by using conser-

vative guidelines, which inflated the risk. Based on the

results (Table 1), the chronic intakes of the thirty one

considered pesticide residues are rather low compared to

the ADI (mostly the cHI were < 1%).

Table 1. Health risk estimation for chronic effects associated

with average pesticide residue.

ADI ADULT TODDLER

Active

substance bw/daybw/day

x10-4 cHI Health

risk

mg/kg

bw/day

x 10-4

cHI Health

risk

acetamipirid0.070.3 < 1 No 1.7 < 1No

alpha-

cypermethrin 0.0150.2 < 1 No 0.6 < 1No

azoxystrobin0.2 0.7 < 1 No 1.5 < 1No

boscalid 0.041.0 < 1 No 3.7 < 1No

captan 0.1 2.3 < 1 No 9.3 < 1No

carbendazim0.020.5 < 1 No 3.0 2 No

chlorpyrifos0.010.5 < 1 No 2.3 2 No

chlorpyrifos

methyl 0.010.1 < 1 No 0.4 < 1No

cypermethrin0.051.7 < 1 No 7.2 1 No

cyprodinil 0.030.5 < 1 No 2.5 < 1No

deltamethrin0.010.0 < 1 No 0.2 < 1No

diazinon 0.00020.4 22 No 2.2 112Yes

dimethoate 0.0010.6 6 No 2.2 22No

dithiocar-

bamates 0.055.5 1 No 22.4 4 No

endosulfan 0.0060.2 < 1 No 0.7 1 No

esfenvalerate0.020.7 < 1 No 3.4 2 No

fenarimol 0.010.1 < 1 No 0.3 < 1No

fenazaquin 0.0050.7 1 No 3.6 7 No

fenhexamid0.2 1.0 < 1 No 3.4 < 1No

fenitrothion0.0050.3 < 1 No 1.7 3 No

fludioxonil 0.370.2 < 1 No 0.6 < 1No

flusilazole 0.0020.4 2 No 1.9 9 No

folpet 0.1 0.9 < 1 No 4.2 < 1No

iprodione 0.060.2 < 1 No 0.9 < 1No

phosalone 0.010.3 < 1 No 1.8 2 No

pirimicarb 0.0350.5 < 1 No 2.1 < 1No

pirimethanil0.170.5 < 1 No 2.7 < 1No

procymidone0.00280.5 2 No 1.0 4 No

tebuconazole0.030.4 < 1 No 1.8 < 1No

tolylfluanid0.1 0.2 < 1 No 0.5 < 1No

triflok-

systrobin 0.1 0.5 < 1 No 2.5 < 1No

ADI - Acceptable Daily Intake [mg/kg]

HI - Hazard Index [%]

B. Łozowicka et al. / Agricultural Sciences 4 (2013) 106-111

110

The safety of Polish consumer (adults) thus seems to

be generally under control in terms of pesticide intakes

through fruit and vegetables consumption. Nevertheless,

some residues such as diazinon and dimethoate need to

be considered more closely given that for a high con-

sumer (97.5 percentile) the cHI were 22% and 6% of the

ADI respectively.

With respect to children the ADI was significantly ex-

ceeded for diazinon at high and frequent fruit consump-

tion (apples), with the cHI 112%. This compound, be-

longing to the organophosphate insecticide group had the

lowest ADI value, at 0.0002 mg/kg body weight of all of

the pesticides being studied. It should be noted that the

residues of diazinon were found in only five of the 392

of tested samples.

Short-term exposure expressed as acute hazard index

(aHI) for children based on the highest consumption at

97.5 percentile and highest concentrations of pesticides

residues detected in fruit are presented in Table 2. In the

all of cases which exceed the MRLs only apple sample

containing flusilazole at concentration 0.09 mg/kg con-

stituted a real threat children health (aHI = 1.297). The

acute risk especially from dimethoate in plum is high and

aHI value approaches the limit value is equal to 1 (aHI =

0.946).

In our work the assessment was based on worst-case

scenarios: the consumption data for consumers who eat a

large portion size of the food were combined with the

highest residue found in fruit from north-eastern Poland.

The evaluation of consumer health risk connected with

the contamination of fruit and vegetables with pesticide

residues shows that it did not pose a danger to neither

subpopulation of small children or adults.

The only noted possible risk for small children was

connected with the residues of diazinon. Children are a

vulnerable group of fruit and vegetables consumers, who

are due to their lower body weight, exposure to relatively

higher pesticide residue levels. A more profound study

regarding this consumer group is recommended.

4. CONCLUSIONS

In conclusion, the results showed that the majority of

fruit samples were in conformity with the relevant legis-

lation and did not contain detectable pesticide residues

(48.2%). Pesticide residues were found in 45.9% of all

monitored fruit samples at or below MRL. While, 5.9%

of samples were above MRL, however, they did not pose

a threat for public health, as demonstrated by the out-

comes of dietary risk assessment.

The results obtained suggest that despite the consum-

ers are exposed to various concentrations of pesticide

residues in fruit from Poland there is no reason for con-

cern and health risk can be excluded.

B. Łozowicka et al. / Agricultural Sciences 4 (2013) 106-111

111

[9] Walorczyk, S. and Gnusowski, B. (2006) Fast and sensi-

tive determination of pesticide residues in vegetables us-

ing low-pressure gas chromatography with a triple quad-

rupole mass spectrometer. Journal Chromatography A,

1128, 236-243. doi:10.1016/j.chroma.2006.06.044

Nevertheless, on the basis of above findings, the need

for residue control programs for pesticides in all fruit

commodities is recommended to protect the consumer

for indiscriminate exposure of pesticides. A future stud-

ies in this area in a longer period of time are required and

would gain a deeper knowledge about the fruit produced

in this country with respect to the use of plant protection

products and their presence in samples.

[10] WHO (1997) Guidelines for predicting dietary intake of

pesticide residues. 2nd revised edition, GEMS/Food

Document WHO/FSF/FOS/97.7, Geneva.

[11] Łozowicka, B., Jankowska, M. and Kaczyński, P. (2011)

Pesticide residues in Brassica vegetables and exposure

assessment of consumers. Food Control, 25, 561-575.

doi:10.1016/j.foodcont.2011.11.017

REFERENCES

[1] Wattenberg, L.W. (1992) Inhibition of carcinogenesis by

minor dietary constituents. Cancer Research, 52, 2085-

2091.

[12] Łozowicka, B. and Kaczyński, P. (2009) Determination of

carbendazim, linuron and glyphosate residues by HPLC

method. Polish Journal Environmental Studies, 18,

100-104.

[2] Radwan, M.A. and Salama, A.K. (2006) Market basket

survey for some heavy metals in Egyptian fruit and vege-

tables. Food and Chemical Toxicology, 44, 1273-1278.

doi:10.1016/j.fct.2006.02.004

[13] Łozowicka, B. and Kaczyński, P. (2009) Dithiocarbamate

residues in food and the potential risk for consumers.

Bromat. Chem. Toksyn., 4, 1155-1160.

[3] Guler, G.O., Cakmak, Y.S., Dagli, Z., Aktumsek, A. and

Ozparlak, H. (2010) Organochlorine pesticide residues in

wheat from Konya region, Turkey. Food and Chemical

Toxicology, 48, 1218-1221. doi:10.1016/j.fct.2010.02.013

[14] SANCO: Method validation and quality control proce-

dures for pesticide residues analysis in food and feed.

Document No. SANCO/10684/2009, 2009.

[15] WHO (World Health Organization) (2003) Inventory of

ICPS and Rother WHO Pesticides evaluations and sum-

mary of toxological evaluations performed by the Joint

Meeting on Pesticide Residues (JMPR), WHO/PCS/02.3.

http://www.who.int.pcs.

[4] Abdulrauf, L.B., Chai, M.K. and Tan, G.H. (2012) Appli-

cations of solid-phase microextraction for the analysis of

pesticide residues in fruit and vegetables: A review.

Journal of AOAC International, 95, 1272-1290.

doi:10.5740/jaoacint.SGE_Abdulrauf [16] PSD (Pesticides Safety Directorate) (2006) New intake

calculation models for consumer intake assessments.

http://www.detergents.gov.uk

[5] Lehotay, S.J. (1996) Supercritical ﬂuid extraction of pes-

ticide residues in fruit and vegetables. Seminars in Food

Analysis, 1, 73-84 [17] Regulation (EC) No 396/2005 of the EC of 23 February

2005 on maximum residue levels of pesticides in or on

food and feed of plant and animal origin and amending

Council Directive 91/414/EEC as follows changes.

[6] Tao, C.J., Hu, J.Y., Li, J.Z., Zheng, S.S., Liu, W. and Li,

C.J. (2009) Multi-residue determination of pesticides in

vegetables by gas chromatography/ion trap mass

spectrometry. Bulletin of Environmental Contamination

and Toxicology, 82, 111-115.

doi:10.1007/s00128-008-9528-0

[18] Szponar, L., Sekuła, W., Rychlik, E., Ołtarzewski, M. and

Figurska, K. (2003) The household food consumption and

anthropometric survey in poland. project report

TCP/POL/8921(A), National Food and Nutrition Institute,

Warszawa, 2003.

[7] Vidal, J.L.M., Arrebola, F.J. and Mateu-Sanchez, M.

(2002) Application of gas chromatography-tandem mass

spectrometry to the analysis of pesticides in fruit and

vegetables. Journal of Chromatography A, 959, 203-213.

doi.org/10.1016/S0021-9673(02)00444-2

[19] Global Environment Monitoring System-Food Contami-

nation Monitoring and Assessment Programme

(GEMS/Food). (2012) GEMS/Food Cluster Diets. World

Health Organization.

http://www.who.int/foodsafety/chem/gems/en/index1.htm

[8] Parveen, Z., Khuhro, M.I. and Rafiq, N. (2005) Monitor-

ing of pesticide residues in vegetables (2000-2003) in

Karachi, Pakistan. Bulletin of Environmental Contamina-

tion and Toxicology, 74, 170-176.

doi:10.1007/s00128-004-0564-0

Openly accessible at