An Overview  

of Multi-residue 

Pesticide Testing

CONTENTS

Introduction .......................................................................................................................................................................................3
  Drivers for Pesticide Testing ............................................................................................................................................4
  Regulatory Limits ......................................................................................................................................................................5
  Multi-residue Pesticide Methods .................................................................................................................................6
Sample Preparation .................................................................................................................................................................... 7
  Sample Extraction .................................................................................................................................................................... 7
  QuEChERS Extraction ...........................................................................................................................................................8
  Dispersive Solid Phase Extraction (dSPE) .............................................................................................................9
  Solid Phase Extraction (SPE) .........................................................................................................................................10
  Gaining Efficiencies in Liquid Handling ................................................................................................................. 11
Sample Analysis ...........................................................................................................................................................................12
  Key Technologies for the Determination of Multi-residues ....................................................................12
  Gas Chromatography Tandem Quadrupole Mass Spectrometry (GC-MS/MS) .....................13
  Liquid Chromatography Tandem Quadrupole Mass Spectrometry (LC-MS/MS) ................14
 Retention .......................................................................................................................................................................................15
  Sample Injection .....................................................................................................................................................................16 
  Matrix Effects ..............................................................................................................................................................................17
  Data Processing ......................................................................................................................................................................18
Why Waters? ...................................................................................................................................................................................19
  Enabling Technologies and Services from Waters .......................................................................................19

Introduction

Plant protection products, more commonly known as pesticides,  
are used to control pests, weeds, and diseases. They may include  
the following: 

■ 

Herbicides to control weeds before and during growth 

■ 

Insecticides to protect seeds and plants from damage by insects

■ 

Nematicides and molluscicides to control attack on growing plants  
by worms and slugs

■ 

Rodenticides to prevent damage and contamination by small 
mammals such as mice and rats during growth and storage

■ 

Fungicides to prevent mold forming on plants in the field and in store

Pesticide residues resulting from the use of plant protection products on 
crops or food products may pose a risk factor for public health or hinder 
trade. This eBook aims to provide a short background on multi-residue 
pesticide analysis, discussing elements of sample preparation and 
sample analysis.

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

DRIVERS FOR PESTICIDE TESTING

WHY TEST FOR PESTICIDES?
Many individual governments or groups of nations 
monitor pesticide residues in domestic and imported 
agricultural produce and other foods each year.  
This monitoring verifies that:

■ 

No unexpected residues are occurring in crops in 
support of the national statutory approvals process  
for pesticides

■ 

Residues do not exceed the statutory maximum 
residue limits (MRLs)

■ 

Human dietary intakes of residues in foods are within 
acceptable levels

In food safety, the phrase “due diligence” refers to being 
able to prove that a business has taken reasonable steps 
to prevent food safety breaches. 

Food businesses are responsible for ensuring that the 
food they produce, or import is compliant with current, 
relevant legislation, including MRLs. This may cover 
more pesticides at concentrations lower than legal limits, 
analysis of finished products as well as ingredients.  
A second reason for food businesses to conduct testing 
is to protect their brand. 

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

REGULATORY LIMITS
Maximum residue levels (MRLs) are established in raw 
food commodities and animal tissues. MRLs are set at 
the highest level of pesticide that the relevant regulatory 
body would expect to find in that crop when it has been 
treated in line with critical Good Agricultural Practice. 

WHAT DOES AN MRL DO?
The main function of an MRL is to act as a control 
mechanism to ensure the product has been correctly 
used according to its label. The value assigned to 
a selected pesticide will vary depending upon the 
commodity for which the MRL was set. 

RESIDUE DEFINITIONS
In some cases, the compound applied as the plant 
protection product is transformed by the time samples 
are taken for analysis. These changes are considered as 
part of the approval process when the residue definition 
is created. For example, in the EU, the residue definition 
for aldicarb is the sum of aldicarb, its sulfoxide, and its 
sulfone, expressed as aldicarb. Residue definitions vary 
between country and commodity. 

5

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

MULTI-RESIDUE PESTICIDE METHODS

WHY MULTI-RESIDUE ANALYSIS?
A primary goal for all laboratories involved 
with the analysis of pesticide residues in food 
is accurately determining as many compounds 
as possible or compounds in a prescribed list 
in the most cost-effective manner. 

Laboratories must address capacity and 
efficiency issues constantly to meet sample 
throughput requirements. 

By implementing multi-residue methods, 
many labs have significantly extended their 
scope of analyses and achieved effective 
and efficient implementation using generic 
extraction, matrix clean-up, and determination 
with gas and liquid chromatography coupled 
with mass spectrometry.

Waters LC-MS/MS and APGC™-MS/MS systems in the NofaLab laboratory.

Read this case study to learn how NofaLab meets the growing 
needs of its customers by improving method development for 
rapid food contaminant detection.

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

Sample Preparation

There are several key aspects to consider prior to sample extraction.  

PREPARING SAMPLES FOR ANALYSIS
Samples received at the laboratory may need work to prepare a test 
sample for analysis by removal of parts (soil, stones, bones, etc.) not 
to be analyzed. Representative samples should be homogenized 
to provide uniform particle size, uniform residue distribution, and 
to increase the surface area available for extraction. To minimize 
degradation of labile compounds, samples of fruit and vegetables are 
comminuted (cut and homogenized) at low temperature (e.g., frozen 
and in the presence of “dry ice” or liquid nitrogen) to transform the 
sample into a fine, homogenous powder which is frozen for storage  
until required for analysis. 

IMPROVING EXTRACTION EFFICIENCY
Test portions should be extracted frozen or while in the process of 
thawing (except dry samples with water content <20%). To improve the 
extraction efficiency of low moisture commodities (cereals, spices, and 
dried fruits), addition of water to the milled samples prior to extraction  
is recommended. When looking at the influence of various factors 
on the extraction yields, the use of samples with incurred pesticide 
residues is advised. 

SAMPLE EXTRACTION

CHALLENGES WITH LEGACY METHODS
Legacy multi-residue methods relied on liquid-liquid extraction 
and clean-up using gel permeation chromatography (GPC) or 
solid phase extraction (SPE). These methods were typically 
labor-intensive, required specialist equipment, and involved 
the use of a lot of glassware and large volumes of organic 
solvents, including chlorinated solvents for the extraction, with 
associated disposal costs.  

MODERN APPROACHES
There are now several generic extraction protocols in common 
use for multi-residue methods:

■ 

Quick, Easy, Cheap, Effective, Rugged, Safe (QuEChERS) 
remains the most popular approach for pesticide residue 
analysis in fruit, vegetables, cereals and sometimes products 
of animal origin1

■ 

Dutch mini-Luke (“NL-”) method using extraction with 
acetone followed by partition with dichloromethane/
petroleum ether (1:1 v/v)2

■ 

Swedish ethyl acetate (“SweEt”) method3.

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

QuEChERS EXTRACTION

WHAT IS QuEChERS?
QuEChERS is a versatile, streamlined approach using a rapid solvent-
based extraction in a centrifuge tube, often followed by dispersive 
solid-phase extraction (dSPE) for clean-up. 

WHY QuEChERS?
QuEChERS requires a small sample size (10 – 15 g) and low solvent 
volume (10–15 mL) so waste disposal costs are minimized (no 
chlorinated solvents). There is no requirement for glassware so no 
need for washing or storage. It speeds up sample throughput and 
simultaneously generates extracts for both GC-MS(/MS) and LC-MS/
MS. Ready-to-use extraction and clean-up tubes are commercially 
available, which contain pre-weighed salts and sorbents. 

The use of acetonitrile (MeCN) provides extraction of a broad range of 
the compounds, from polar to nonpolar. The addition of buffering salts 
into a mixture of water and MeCN causes the formation of a two-phase 
system and improves recoveries of pH-dependent analytes.

>> Click here to learn more about our commercially available products.

Analyst transferring QuEChERS extract to dSPE tube.

Watch this video on Simplifying your QuEChERS 
Extractions using DisQuE™ Sample Preparation Products.

Extraction

Transfer 10 g sample into 50 mL tube, add internal standards (optional) and 10 mL MeCN; shake vigorously (1 min)

Partition

Add salts (e.g. 4 g MgSO

4, 1 g NaCl, 0.5 g C6H9NaO8 and 1 g Na3C6H5O7); immediately shake vigorously (1 min) 

Centrifugation 

5 min at > 3000 g (RCF) and store extracts from fat or wax containing samples in freezer overnight

Clean-up

LC-MS/MS 

GC-MS/MS 

QuEChERS CEN method workflow.

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

DISPERSIVE SOLID PHASE EXTRACTION (dSPE)

WHAT IS dSPE?
Dispersive solid phase extraction (dSPE) is a rapid, simple, and 
straightforward technique suitable for the clean-up of extracts from a 
wide variety of food and agricultural commodities. 

An aliquot of acetonitrile supernatant from a QuEChERS extraction is 
added to a disposable tube containing sorbent(s). The tube is shaken, 
centrifuged and the supernatant is collected for further analysis. Unlike 
in conventional SPE, it is the co-extractives that are retained on the 
sorbent whilst the analytes remain in the solution. Varying amounts 
of different sorbents are added depending on the commodity and 
pesticides targeted. 

The most popular commercially available kits were developed in 
accordance with the official standardized version of QuEChERS and 
typically include magnesium sulfate to remove any remaining water  
and one or more of three sorbents for the dSPE step:

■ 

Graphitized carbon black (GCB; for pigments)

■ 

Primary-secondary amine (PSA; for sugars, fatty acids, organic acids) 

■ 

Octadecyl-bonded silica (C

18; for long chain hydrocarbons,  

lipids, waxes)

dSPE sorbent suggestions for different commodities.

Commodity Type

Cleanup Provided

Size

AOAC Method 2007.01

CEN Method 15662

General Fruits and 

Vegetables  

(Celery, Head Lettuce, Melon)

Removes polar 

organic acids, some 

sugars and lipids

2 mL Tubes 

15 mL Tubes

50 mg PSA, 150 mg MgSO

4 Part #186004572 

400 mg PSA, 1200 mg MgSO

4 Part #186008072

25 mg PSA, 150 mg MgSO

4 Part #186004831 

150 mg PSA, 900 mg MgSO

4 Part #186004833

Fruits and Vegetables with 

Fats and Waxes (Cereals, 

Nuts, Dairy, Avocado)

Removes polar 

organic acids, some 

sugars, more lipids 

and sterols

2 mL Tubes 

15 mL Tubes

50 mg PSA, 50 mg C

18, 150 mg MgSO4 Part 

#186004830 

400 mg PSA, 400 mg C

18, 1200 mg MgSO4 Part # 

186008073

25 mg PSA, 25 mg C

18, 150 mg MgSO4 Part 

#186004832 

150 mg PSA, 150 mg C

18, 900 mg MgSO4 Part 

#186004834

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

SOLID PHASE EXTRACTION (SPE)

LIMITATIONS OF dSPE
The use of dSPE is not without problems, especially when dealing with 
certain commodities. The dSPE sorbents can decrease the recovery of 
some compounds and may not provide sufficient clean-up of the extract, 
increasing the possibility of faster contamination of the instrumentation. 

ALTERNATIVES TO dSPE
Laboratories may turn to conventional trap and elute SPE, which can be 
more effective for removal of matrix co-extractives but increases the risk 
of poor recovery of certain pesticides. 

Using SPE in pass-through mode, the extract is passed straight through 
the cartridge and the matrix co-extractives remain on the sorbent and 
analytes are collected in the eluant.

One advantage over conventional SPE is the omission of the extra 
load, rinse and subsequent elution steps typically involved with SPE. 
SPE using Oasis™ PRiME HLB can be used as an alternative to dSPE, 
especially where removal of lipids is important or to avoid use of PSA  
or GCB sorbents in dSPE. 

Oasis™ PRiME HLB Plus Cartridge, Pass-Through SPE

Discover the benefits a simple pass through offers for the 
removal of chlorophyll from highly pigmented samples in  
this 

application brief.

10

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

GAINING EFFICIENCIES IN LIQUID HANDLING 

LIQUID HANDLING: FROM PAINS TO GAINS
A common and significant step in multi-residue pesticide 
testing workflows is the preparation of matrix matched 
standards. The accuracy, repeatability and traceability  
of this step are essential for the reliable quantitation  
of pesticides. 

Automation of routine liquid handling steps such  
as this can provide several benefits, including:

■ 

Minimized pipetting errors

■ 

Reduced waste

■ 

Increased traceability

■ 

Reduced risks of repetitive injury

■ 

Freeing analysts to be deployed for other  
high value tasks

Read this application note: Automating 
Preparation of Matrix-Matched Standards 
for Pesticide Residue Analysis Using the 
Andrew+™ Pipetting Robot. 

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

Sample Analysis
KEY TECHNOLOGIES FOR THE DETERMINATION OF 

MULTI-RESIDUES
Mass spectrometry coupled with both gas chromatography (GC) 
and liquid chromatography (LC) is needed to provide comprehensive 
analysis of the wide range of pesticide residues. Tandem quadrupole 
mass spectrometry (MS/MS) has become the most widely adopted 
technique due to its high selectivity in multiple reaction monitoring 
(MRM) mode and sensitivity to meet global MRL regulations.

Like the evolution of sample preparation techniques, MS/MS has 
continued to develop to meet users’ growing needs, where:

■ 

Sensitivity to exceed MRL requirements has allowed for sample 
preparation to be streamlined and reduce matrix loaded

■ 

Acquisition speeds yield sufficient data points to reliably quantify 
even the most well-focused and overlapping peaks

■ 

The reduced instrument footprint offers laboratories improved 
performance per square meter of coveted bench space

Read this application note on the determination of  
multi-residue pesticides in fruits and vegetables by  
UPLC and APGC coupled with the Xevo™ TQ-S micro.

12

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

GAS CHROMATOGRAPHY TANDEM QUADRUPOLE MASS 

SPECTROMETRY (GC-MS/MS)
Originally gas chromatography coupled to mass spectrometry 
(GC-MS) methods were mostly based on selected ion monitoring 
(SIM) or full scan modes, using either single quadrupole or ion 
trap mass analyzers. However, the determination of GC-amenable 
pesticides in food by using MS/MS has grown considerably over the 
last decade as this provides higher selectivity and sensitivity that 
minimizes most chromatographic interferences. 

SOFTER IONIZATION FOR ENHANCED SENSITIVITY AND SELECTIVITY
GC-MS/MS typically uses EI at 70 eV, extensive fragmentation is 
often observed so the selection of the precursor ion for MS/MS is 
often a compromise between sensitivity and selectivity. APGC™ is 
a soft ionization technique which generates higher abundance of 
molecular ions, with less fragmentation than conventional EI. As 
the molecular ion (or protonated molecular ion) is highly abundant 
under the soft ionization occurring in APCI, selectivity and sensitivity 
are notably enhanced when it is used as the precursor ion for MRM 
methods. Moreover, APGC operates at atmospheric pressure which 
removes the restriction imposed by pumps, allowing a much wider 
range of flow rates for GC separations and use of alternative gases  
to helium, such as nitrogen.

Read this white paper on Atmospheric Pressure Gas 
Chromatography (APGC) to learn more.

Waters APGC System, the Xevo TQ-XS.

13

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

LIQUID CHROMATOGRAPHY TANDEM QUADRUPOLE 

MASS SPECTROMETRY (LC-MS/MS)
With the introduction of UltraPerformance Liquid 
Chromatography™ (UPLC™), laboratories reported significant 
method efficiency benefits over traditional LC. The true 
benefits of this technology was further realized with the 
advancement of MS/MS technology almost a decade  
later, offering:

■ 

Improved system sensitivity, allowing for simple dilution 
of crude QuEChERS extracts, avoiding timely and labor-
intensive extract cleanup

■ 

Increased MS/MS scanning capabilities enabling the 
analytical scope in a single injection to be extended, 
without impacting data quality

■ 

Reduced analytical runtimes, allowing twice the samples 
to be analyzed by UPLC-MS/MS vs traditional LC-MS/MS 

■ 

Less solvent usage and associated disposal costs  

ACQUITY™ UPLC Premier and Xevo TQ Absolute system

Read this application note: Multi-residue Method for 
the Quantification of Pesticides in Fruits, Vegetables, 
Cereals and Black Tea using UPLC-MS/MS.

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

RETENTION

WHAT IS RETENTION TIME?
Retention time (RT) is the time between the start of an injection to the 
emergence of the peak maximum of the analyte(s). 

WHY IS RT IMPORTANT?
If this interaction is too short, then little to no chromatography has taken 
place, separations will be less stable, and there will be a high chance 
of ion suppression when LC-MS is used. The column void volume (v) 
is a measure of the internal volume inside the column packed with the 
stationary phase particles and can be estimated from a column’s length 
(L) and internal diameter (ID). 

Analytical quality control, performance and method validation guidelines 
such as SANTE/11312/2021 state “the minimum acceptable retention 
time for the analyte(s) should be at least twice the retention time 
corresponding to the void volume of the column.”4

Methamidophos retention time in different samples.

Spinach

Strawberry

Soybean

Wheat flour

Methamidophos

Acephate

Methomyl

Black tea

Visit the Column Coach to Assist in Column Selection  
for your Analysis.

15

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

SAMPLE INJECTION
Pesticides, such as methamidophos and acephate, are polar and elute 
early in the chromatogram. Injecting samples containing moderate 
amounts of organic solvent (≥25%) on a reversed-phase column often 
results in fronting and/or split peaks for the early eluting compounds. 
Reducing the organic content used in the sample diluent prior to transfer 
onto the column may help to improve the peak shape of early eluting 
analytes. However, maintaining a portion of organic in the extract is 
essential for analyte stability.

ALTERNATIVES TO MANUAL DILUTION
Post injector mixing can allow the injection of typical QuEChERS extracts 
into high aqueous mobile phase without compromising peak shape.  
An extension loop is placed in between the injector port and column. 
Before the injection is made, the extension loop is filled with the high 
aqueous mobile phase, which provides more volume to aid dispersion  
of the sample into the aqueous solvent prior to transfer onto the column. 

Methamidophos in a QuEChERS extract with different acetontrile and water ratios.

Read this application note: Multi-residue Method for 
the Quantification of Pesticides in Fruits, Vegetables, 
Cereals and Black Tea using UPLC-MS/MS.

Increasing 

aqueous 

content

100% MeCN QuEChERS extract 
of a vegetable

25% MeCN QuEChERS extract  
of a vegetable

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

MATRIX EFFECTS
The hyphenation of chromatographic and mass spectrometry 
technologies has revolutionized food contaminant testing laboratories. 
However, one major drawback is the potential for the phenomenon of 
matrix effects. The influence of matrix on the reliability of your method 
should be determined when implementing new methodologies, 
commodities or analytes into your laboratory’s analytical scope.

COMPENSATING FOR MATRIX EFFECTS
Matrix effects are known to occur frequently in LC-MS/MS methods 
and should be assessed during method validation. Ionization efficiency 
in the source is impacted, resulting in ion suppression or enhancement. 
These effects are caused by the co-elution of matrix co-extractives 
with analytes. Significant variations in the magnitude of matrix effects 
have been observed between different commodities. The use of matrix-
matched calibration is recommended to mitigate for matrix effects.

0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

1800000

2000000

0

5

10

15

20

25

Peak response

Concentration (ng/ml)

Matrix

Solvent

Matrix effects causing ion suppression of a matrix matched calibration curve.

Watch this bite-size webinar on compensating for matrix 
effects in complex samples to learn more.

17

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

DATA PROCESSING
Whilst quantitation itself is a routine 
experiment, the analysis of hundreds of 
pesticides, each with two MRM transitions 
creates a significant amount of data for review. 
Along with peak integration, retention time, 
ion ratios, signal to noise, calibration curve 
data and quality control standard performance 
must be assessed. As the scope of analytes 
continues to increase, the data review can create 
bottlenecks for routine testing laboratories.

Data processing software with Exception 
Focused Review (XFR) functionality 
allows customized rule-sets based on the 
laboratory’s standard operating procedures 
(SOPs) to be created and enables analysts to:

■ 

Review data more efficiently  
and consistently

■ 

Quickly identify injections that fall outside 
the laboratory’s analytical quality system

■ 

Visually and quickly identify samples  
with suspected incurred residues

■ 

Submit the sample batch for approval  
with confidence

The MS Quan Software Dashboard makes it easy to visualize your data.

Read this white paper on the benefits of waters_connect™ 
MRM Processing Application, MS Quan.

18

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

Why Waters?
ENABLING TECHNOLOGIES AND 

SERVICES FROM WATERS
The use of plant protection products 
helps to secure global food supplies 
but can leave pesticide residues in our 
food chain. With an extensive regulatory 
framework in place across the globe and 
varying physicochemical characteristics 
of pesticide classes, food manufacturers 
and testing services need flexible, fast and 
reliable testing solutions. Whether meeting 
food safety regulations, quality control 
stipulations or undertaking metabolite 
discovery, efficiency is paramount to  
keep pace with demands.

With an extensive portfolio of instruments, 
services and support we provide quality, 
knowledge and confidence for optimum 
productivity in your laboratory. We partner 
with you to ensure a successful purchase 
outcome, employing our global team of 
application experts to assist in instrument 
setup and user training.

COLUMN 

CHEMISTRIES

APGC

HPLC
UPLC

MS/MS

SOFTWARE

INFORMATICS

APPLICATION 

SPECIALISTS

AWARD

WINNING

SERVICE

LEASING FINANCE

INDUSTRY LEADING SUPPORT

Enabling technologies across  

the analytical workflow. 

>>Click each icon to learn more. 

19

An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

Resources

1.  Anastassiades M et al. (2003). Fast and easy multi-residue method 

employing acetonitrile extraction/partitioning and dispersive solid-
phase extraction for the determination of pesticide residues in 
produce. J AOAC Int. 86(2):412-31

2.  Lozano A et al. (2016). Miniaturisation and optimisation of the Dutch 

mini-Luke extraction method for implementation in the routine multi-
residue analysis of pesticides in fruits and vegetables. Food Chem. 
192: 668–681

3.  Pihlström et al. (2007). Analysis of pesticide residues in fruit and 

vegetables with ethyl acetate extraction using gas and liquid 
chromatography with tandem mass spectrometric detection.  
Anal. Bioanal. Chem. 389(6):1773-89

4.  SANTE 11312/2021. Analytical Quality Control and Method Validation 

Procedures for Pesticide Residues Analysis in Food and Feed. 

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An Overview of Multi-residue Pesticide Testing

Introduction

Sample Preparation

Sample Analysis

Why Waters?

Waters Corporation 
34 Maple Street 
Milford, MA 01757 U.S.A. 
T: 1 508 478 2000 
F: 1 508 872 1990 
waters.com

Waters, The Science of What’s Possible, Oasis, Andrew+, Xevo, ACQUITY, UltraPerformance 
Liquid Chromatography, UPLC, waters_connect, DisQuE are trademarks of Waters 
Corporation. All other trademarks are the property of their respective owners.

©2022 Waters Corporation. Produced in the U.S.A.  May 2022  720007619EN  GJ-PDF

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