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Document Number:

MAN-000059

Revision #: 03

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Title: 

ORA Lab Manual Vol. IV Section 6 - Elemental Analysis Orientation and 

Training (IV-06)

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Sections in This Document

1. Purpose ....................................................................................................................................2

2. Scope .......................................................................................................................................2

3. Responsibility............................................................................................................................2

4. Background...............................................................................................................................3

4.1. FDA Center for Food Safety and FDA Center for Veterinary Medicine..........................3

4.2. Toxic Elements in Food, Feed and Foodware ...............................................................3

4.2.1. Toxic Element in Food and Feed .....................................................................3

4.2.2. Lead and Cadmium in Food ware....................................................................5

4.2.3. Mercury in Foods and Feed .............................................................................6

4.2.4. Mercury in Cosmetics ......................................................................................7

4.2.5. Nutritional Elements in Foods, Feeds, and Dietary Supplements....................8

4.3. Methods and Technology...............................................................................................8

4.3.1. Qualitative Identification of Lead in Ceramicware and Solder Alloys...............8

4.3.2. XRF analysis....................................................................................................9

4.3.3. Leachable Lead and Cadmium from Ceramicware by ICP- AES ..................10

4.3.4. Microwave Digestion......................................................................................10

4.3.5. Multi-Element, Simultaneous Sequential/Quantitative Analysis of Food and Feed 

by ICP-AES....................................................................................................11

4.3.6. Multi-Element, Simultaneous Sequential/Quantitative Analysis of Foods and 

Feed by ICP-MS ............................................................................................11

5. References .............................................................................................................................12

6. Procedure ...............................................................................................................................15

6.1. Sample Preparation .....................................................................................................15

6.1.1. Food Edible Portion .......................................................................................15

6.1.2. Food Homogenization....................................................................................15

6.1.3. Digestion and Separation...............................................................................15

6.1.4. Contamination Control ...................................................................................15

6.2. General Analytical Operations .....................................................................................15

6.2.1. Safety.............................................................................................................15

6.2.2. Terminology ...................................................................................................15

6.2.3. Uncertainty.....................................................................................................15

6.2.4. Special Calculations.......................................................................................15
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6.2.5. Reference Materials.......................................................................................15

6.2.6. Performance ..................................................................................................15

6.2.7. Typical Element Concentrations ....................................................................15

6.3. Analytical Methods.......................................................................................................15

7. Glossary/Definitions................................................................................................................15

8. Records ..................................................................................................................................15

9. Supporting Documents ...........................................................................................................16

Document History ...................................................................................................................16

Change History.......................................................................................................................17

Attachments............................................................................................................................17

1. Purpose

The purpose of this document is to provide training guidance to analysts 

responsible for determination of nutritional and toxic elements in food, feed, 

food ware, and other regulated products. This is general information to 

supplement on-the-job training, proficiency testing for beginning analysts, and 

formal classroom training (OTED courses LB 212 - Fundamentals of Elemental 

Analysis by ICP-MS, LB 307 - ICP and XRF Methods of Analysis for Nutrients 

and Toxic Elements, and LB 404 - Speciation Fundamentals in ICP-MS).

2. Scope

This document applies to all analysts involved in the analysis of samples for 

determination of nutritional and/or toxic elements in FDA samples. 

3. Responsibility

It is the responsibility of laboratory management and quality assurance 

management to ensure that all analysts are properly trained and have the 

prerequisite skills necessary to conduct elemental analysis of FDA samples.
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4. Background

Humans and animals are exposed daily to numerous elements, in varying 

forms and at different levels, through food (feed), water, and other FDAregulated products (cosmetics).

Major essential elements include C, H, O, N, S, Ca, P, K, Na, Cl, and Mg. C, 

H, O, N, and S make up the bulk of the elemental constituents of plants and 

animals and are the major components of the organic substances in tissue. Fe, 

Zn, Cu, Co Mn, I, Mo, Cr, Se, F, (B for plants) have identified functions 

meeting the definition of essential elements in humans and animals. Whether 

an element is essential has some bearing on an element’s toxicity. Essential 

elements under homeostasis, (i.e., the level of absorption, body stores, and or 

excretion is under physiological control), tend to have a lower relative toxicity. 

However, many factors, such as the level of exposure, the form of the element, 

the sensitivity of the host, and the physiological and nutritional status of the 

host, affect the toxicity of an element.

Nonessential and essential elements can be toxic. Nonessential elements 

where human toxicity has been reported include Pb, Cd, Hg, As, Al, Ba, Li, Pt, 

Te, Ti, Sb, Be, Ga, In, V, Ni, Sr, Sn, Ge, Ag, Au, Bi, Tl, and U. The essential 

elements, F, Co, Fe, Mo, Cu, Mg, Se, Cr, Mn, and Zn are of practical

toxicological significance. Se is the most toxic essential mineral elements. 

Presently, Pb, Cd, Hg (as methylmercury), and As (inorganic forms) are of the 

greatest concern and have the greatest program emphasis.

4.1. FDA Center for Food Safety and FDA Center for Veterinary Medicine

As part of their responsibilities for ensuring food safety, the FDA Center for 

Food Safety and Applied Nutrition (CFSAN) and FDA Center for Veterinary 

Medicine (CVM) routinely monitor the level and potential dietary uptake of toxic

elements (contaminants) in food, feed, and food ware. FDA Compliance 

Programs detail the sample collection and analysis for the determination of 

arsenic, lead, and cadmium in food, feed, and food ware, as well as methyl

mercury, inorganic arsenic and selenium in food and feed.

4.2. Toxic Elements in Food, Feed and Foodware

Compliance Programs guide field and laboratory operations which cover toxic 

elements in targeted sampling. CPG 7304.019A (food) and CPG 7304.019B

(foodware) are the applicable Compliance Programs for the toxic elements in 

food. CPG 7371.003 provides guidance for the Feed Contaminants Program.

4.2.1. Toxic Element in Food and Feed

See Compliance Program Guidance Manual 7304.019A
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Toxic Elements in Foods. Lead and cadmium are identified as the toxic 

elements of concern in foods; particular emphasis is placed on foods 

consumed by children who are the most sensitive to adverse side effects.

There are few universal regulatory limits, i.e., tolerances, for toxic elements in 

foods; sample results that exceed normal concentrations are brought to the 

attention of CFSAN, who will conduct Health Hazard Evaluation of potential 

health hazards from the quantity of the toxic element found based upon food 

consumption of the product.

FDA has developed referral levels (RLs) for arsenic, lead, cadmium, and 

mercury for several commodities. When the consumption of a contaminated

food has exceeded a RL, regulatory action may be taken on an ad hoc basis. 

Food Chemical CODEX (FCC) lists many internationally recognized standards 

for lead in foods and food ingredients. While these are not regulatory 

tolerances, the FCC are often employed as lowest limits of actions for imported 

foods.

The prohibition of lead soldered cans and the removal of lead from gasoline 

have significantly reduced the lead exposure to the average consumer. The 

Total Diet Surveys indicate the average lead intake from food has decreased 

more than 95% since the 1970s. Nonetheless, FDA remains concerned about 

lead in regulated products, especially since more than half of our foods now 

come from outside the U.S., and a significant number of children in the U.S. 

remain exposed to excessive amounts of lead. Lead in the diet can be 

attributed to natural sources of lead in the soil, deposition of lead particles onto 

crops, pollution (leaded gasoline usage), food processing and packaging 

techniques, spices, herbal supplements, ayurvedic medicine, and folk 

remedies. The use of lead-based solders in food cans is now prohibited 

(21CFR 189.240). Although the use of lead-based pigments in food wrappers 

is not prohibited, the United States and European Commission voluntarily 

stopped this practice. Candy food wrappers from other countries, particularly 

Mexico, have been found to contain percent levels of lead. Lead is found in 

folk remedies such as Azarcon, Greta, herbal medicines, and unapproved 

dyes in eye cosmetics (kajal, surma, kohl) from the Far and Middle Eastern 

countries. Spices, sourced from India, have recently been found to contain 

elevated levels of lead and chromium. Yellow lead chromate and red lead 

chromate appear to be contaminants added to enhance the color of the spice.

Cadmium is found in foods naturally and due to pollution. Cadmium is emitted 

into the atmosphere from smelters and waste incineration plants; the use of 

municipal sludge can dramatically increase cadmium levels in food. Recently 

cultivated agricultural areas derived from ancient seabeds are prone to 

producing elevated levels of cadmium in foods (e.g., spinach, lettuce). 
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Arsenic and selenium both occur naturally in foods. Each can be present at 

toxicologically significant levels in groundwater and in soils.

Arsenic compounds are released to the atmosphere from natural and industrial 

sources. The major sources of arsenic emissions are the smelting of metals, 

burning of fossil fuels, and application of pesticides and herbicides. The 

arsenic compounds may accumulate in agricultural and horticultural soils and 

plants. 

Arsenic in food is most often in alkylated forms. The alkylated forms of arsenic 

that arise in plants, shrimp, and some other animals have a relative low order 

of toxicity. Arsenate and arsenite are far more toxic and have proven to be 

carcinogenic in humans.

Selenium is the most toxic essential mineral element. Selenium often occurs 

as selenium analogues of sulfur-containing amino acids and metabolites in 

plants. While there have been numerous selenium intoxications reported for 

human and animals, these poisonings have been mainly due to errors in 

manufacturing dietary supplements and feed selenium supplements. Although 

human toxicity to selenium has been reported in China and other parts of the 

world where extreme selenium pollution exists, selenium deficiency appears to 

be the more significant public health concern.

Pigments used to decorate ceramicware, or glazes coating ceramicware may 

contain lead or cadmium. Traditional wares (e.g., Chinese classic enamel-onporcelain wares, Mexican glazed folk terra cotta) have been found to contain 

excessive amounts of lead. Glazes that are improperly formulated, applied, or 

fired may permit unacceptable amounts of lead or cadmium to leach into food. 

The following colors in glaze or decorations are often indicative of ceramicware 

that may release cadmium: red, orange, yellow.

4.2.2. Lead and Cadmium in Food ware

See Compliance Program Guidance Manual 7304.019B Toxic Elements in 

Food ware. 

The Food Additives provision of the FD&C Act does not permit a harmful level 

of a substance to migrate from the surface onto a food or beverage. Toxic 

Elements in Food ware (CPGM 7304.019B) focuses on lead and cadmium 

found in ceramicware and silver-plated hollowware used for eating, storing, 

holding, and cooking foods.

The FDA and the State Administration of Entry/Exit Inspection and Quarantine 

of China (recently renamed the China National Certification and Accreditation 

Administration or CNCA) implemented a Memorandum of Understanding 

(MOU) pertaining to the safety of ceramic tableware produced in China and 
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exported to the United States. The MOU specifies a certification system for 

ceramic tableware production facilities in China. This certification system is 

expected to provide FDA with reasonable assurance that ceramicware 

produced in these facilities and exported to the United States will not exceed 

FDA action levels for leachable lead and cadmium.

The CPGM focuses on the rate of compliance for Chinese Ceramicware from 

non-certified and certified factories, audits the effectiveness of the China 

certification program in improving the safety of ceramicware exported to the 

United States, and concentrates on sampling countries with prior violations, 

particularly small shipments entering from Mexico.

Monitoring of ceramicware is conducted in two steps. Screening tests for 

ceramicware are conducted in the field to identify items that are likely to 

contain leachable lead. Based on the results of the screening tests, official 

samples are collected and sent to the laboratory for further testing. There is no 

screening test for cadmium in ceramicware or lead and cadmium in silverplated hollowware. The investigator is directed to look for signs of improper 

glazing on the product, and/or collecting samples with those colors that may 

contain lead or cadmium.

In the absence of codified regulations or tolerances for ceramicware and silverplated hollowware, FDA has established interim action guidelines for lead 

Compliance Policy Guide (CPG) Sec 545.450 and CPG Sec. 545.500 and 

cadmium CPG Sec 545.400. The surveillance of leachable lead and cadmium 

in ceramicware continues to be a program priority.

Past FDA regulatory efforts, an MOU with China, efforts by the commercial 

sector, and state regulations (e.g., California Proposition-65), have led to a 

vast improvement in the performance of daily-use tableware regarding the 

leachability of lead and cadmium. Most daily-use ceramicware pose relatively 

few regulatory problems for leachable levels of lead and cadmium. The 

traditional wares (especially from China) and folk terra cotta wares from 

Mexico and Central American countries continue to pose lead exposure risk, 

especially for children and the fetus. Many other elements are used in 

ceramicware bodies, their glazes, and decorations. Ba, Sb, Co, Cr, and others 

may leach from ceramicware. However, the regulatory significance of these 

elements has not been evaluated.

4.2.3. Mercury in Foods and Feed

See Compliance Policy Guide, Section 540.600, Fish, Shellfish, Crustaceans,

and other Aquatic Animals – Methyl Mercury.
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Mercury, primarily as methyl mercury, was first identified as a regulatory issue 

in seafood in the 1970s. Mercury occurs naturally in the environment and is 

released from the Earth’s crusts and oceans. Mercury is also released from 

fossil fuels, such as coal, and burning industrial wastes. Fish absorb methyl 

mercury from water as it passes over their gills and through feeding aquatic 

organisms; methyl mercury binds tightly to proteins in fish tissue.

Studies of people exposed to high levels of mercury in highly contaminated 

fish were conducted in Minnamata, Japan. Over one hundred people died from 

eating fish (often daily over extended periods) from waters that were severely 

polluted with mercury from industrial discharge. Mercury poisoning occurred in 

unborn fetuses and children. An epidemic of mercury poisoning occurred with 

a wheat seed treated with alkyl mercury fungicide.

Presently, the FDA regulatory guideline for methyl mercury in seafood (CPG 

Sec 540.600) is one part per million (ppm) methylmercury expressed as Hg. 

FDA’s action level of one ppm for methyl mercury in fish was established to 

limit the consumers methyl mercury exposure to levels ten times lower than 

the lowest levels associated with adverse effects. Seafood consumption 

recommendations are available based on established Hg surveillance 

environmental data.

4.2.4. Mercury in Cosmetics

The passage of the Food, Drug, and Cosmetic act in 1938 allowed for FDA 

regulation of cosmetic products, and additional legislation passed in 1977 

required U.S. manufacturers to list ingredients on the labels of cosmetic 

products.

The use of mercury in some face cream products is intentional, as it provides 

skin bleaching properties and can reduce freckles, age spots, and brown spots 

by temporarily blocking the production of melanin. This temporary effect leads 

to continual use of the product. The presence of mercury at percent levels 

have been found in some of these products. This appears to be more common 

in imported products which are manufactured and sold in Asia, Mexico, and 

the Middle East, and can in some cases be imported into the U.S., purchased 

over the internet, or brought in personally from abroad for personal use.

Repeated use of products containing high levels of mercury can lead to 

chronic exposure through dermal contact. In addition, some of these products 

are known to contain volatile forms of mercury, and hence pose additional risk 

of exposure via inhalation. The use of mercury in cosmetics was banned by 

the EU in 1976 and by the FDA in 1990. FDA regulations allow for cosmetics 

meeting conditions of good manufacturing practices to have trace levels of 
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mercury at levels of less than one μg/g (ppm), except for cosmetics used only 

in the area of the eyes where mercury is still allowed as a preservative at 

levels no more than 65 ppm [21 CFR 700.13]. Mercury containing face cream 

products with claims such as “skin-bleaching” can be interpreted as an 

unapproved drug and/or an adulterated product.

4.2.5. Nutritional Elements in Foods, Feeds, and Dietary Supplements

Nutritional elements (secondary and minor nutrients) are determined in foods 

and feed to evaluate the levels of nutrients in foods, dietary supplements and 

feeds as compared to NLEA food labels, DSHEA dietary supplement labels, 

and feed labels. Infant formula, medical foods, dietary supplements, food, and 

feed are routinely tested for these nutrient types. Compliance Programs 

7321.002 Medical Foods, 7321.005 NLEA Nutrient Sample Analysis, 7321.006 

Infant Formula, 7321.008 DSHEA Dietary Supplement, Total Diet Study, and 

7371.003B Feed Contaminants Program.

Total Diet Study (TDS), sometimes called the Market Basket Study, is an 

ongoing FDA program that determines levels of various pesticides, 

contaminants, and nutrients in foods for the purpose of estimated intakes of 

these substances in representing diets of selected age-sex groups in the 

United States Population. Elements analyzed include the following: arsenic, 

cadmium, calcium, copper, iron, lead, magnesium, manganese, mercury, 

nickel, phosphorous, potassium, selenium, sodium, and zinc.

4.3. Methods and Technology

This section is intended to expose the analyst to some of the more frequently 

used methods for determining toxic and nutritional metals in food, feed, and 

foodware. For more detailed information regarding methods on the 

determination of these and additional elements, standards, sample 

preparation, digestions, instrumentation, or data treatment consult the CFSAN 

website and the Elemental Analysis Manual (EAM) . 

4.3.1. Qualitative Identification of Lead in Ceramicware and Solder Alloys

Because the scope of the ceramicware program is limited to leachable lead 

and cadmium, and the use of lead is routine in ceramicware items, FDA 

investigators often employ qualitative tests to determine whether the item 

leaches (or contains) lead, and therefore warrants collection.

An equivalent, FDA validated test kit does not exist for cadmium. The 

presence of cadmium is usually “signaled” by the presence of rich yellow or 

red decorations on the food-bearing surface of the item. FDA developed the 

Quick Color Test (QCT) for Lead. The QCT test for lead, and similar forms of 
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the test (e.g., the Rapid Abrasion Test (RAT), have been commercialized (e.g., 

LeadCheck SwabsTM, by Hybrivet. The tests determine if an item bears 

leachable lead, or the item bears a leachable or non-leachable lead in the 

glaze or a decoration. Some of these commercial test kits have also been 

validated for testing for the presence of lead in the solder of food cans, a 

prohibited practice. EAM 4.6 may be used to determine leachable lead from 

soldered cans (more information in §6.2.3).

The following documents, articles and methods are useful references: 

Compliance Program Guidance Manual 7304.019B Toxic Elements in 

Foodware (Domestic & Import); Gould et al. (1988). 

Analytical Letters, 2145-2154; Capar, S. G. (1998, August). 

Laboratory Information Bulletin (LIB) 4127 Ceramic foodware lead screening 

using test kits. 

Journal of AOAC International, 719-722; Capar, S. G., Anderson, D.L., 

Hughes, D. D., Jacobs, R.M. (1996). 

Laboratory Information Bulletin, (LIB) 4041 Identification of lead solder on a 

metal can seam. 

4.3.2. XRF analysis

X-ray fluorescence (XRF) is a rapid and usually non-destructive analytical 

technique for measuring the levels of elements in samples. Two core types of 

XRF are energy dispersive XRF (EDXRF) and wavelength dispersive XRF 

(WDXRF). The addition of the word “spectrometry” makes the acronyms 

XRFS, EDXRFS, and WDXRFS, respectively. Hardware and software options 

are very-well developed - highly capable and functional.

XRF can potentially measure all elements with Z ≥ 11 (i.e., Al and heavier) but 

does not provide chemical form. It can be an add-on capability, such as in 

electron microscopy, but is usually stand-alone. XRF’s strongest application is 

in inorganic fields of study such as archaeology and minerology. For example, 

Perseverance (the rover in NASA’s Mars 2020 mission) will use XRF to study 

the composition of Mars’ surface. Although XRF is not widely used in food 

analysis, it can have application in the analysis of food safety. 

XRF is a surface analysis technique where excitation causes x-rays to be 

emitted from atoms present in only the top few microns of sample surfaces. It 

is, therefore, best suited for smooth and uniform surfaces. The x-ray 

energies/wavelengths indicate which elements are being detected and their 

intensities give quantitative information. WDXRFS is the more precise and has 
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lower detection levels than EDXRFS, but WDXRFS systems are relatively 

large (and expensive), requiring significant floor space as opposed to EDXRFS 

systems, many of which are benchtop or even portable enough to use in a 

‘point-and-shoot’ procedure. A typical application for the latter is to measure 

lead in wall paint. Several FDA laboratories have portable EDXRFS systems 

that can be used for investigations such as looking for lead and cadmium in 

ceramicware surfaces.

4.3.2.1. Methods

A. Detection and Confirmation of Toxic Element Using the Innov-X-X-5000 

Field Portable X- Ray Fluorescence Analyzer

B. LIB #4461 Use of X-ray Fluorescence Spectrometry for Screening 

and/or Accurate Quantitation of Toxic Elements in Supplements. 

C. LIB #4542 Use of Field Portable XRF for Screening and Quantification 

of Mercury in Face Creams. 

4.3.3. Leachable Lead and Cadmium from Ceramicware by ICP- AES

Inductively coupled plasma atomic emission spectrometry (ICP-AES, 

commonly atomic is interchanged with optical, and spectrometry interchanged 

with spectroscopy) is a rapid, multi-element technique. Samples, typically 

consisting of an aqueous acid liquid, either by prior dilution/dissolution with an 

acid solution (e.g., leachate), or as the end product of an acid digestion (e.g.,

via microwave assisted decomposition, §6.2.4) are introduced to the ICP. 

During the free electron – analyte collision, analyte electrons absorb energy 

and are promoted to higher (excited) energy levels. Excited electrons drop 

back down to ground energy levels and excess energy is liberated as light. 

Each element has its own characteristic light spectrum. The AES uses an 

Echelle grating to separate wavelengths and light is quantified on a detector. 

Light intensity is measured and calibrated against known standards and the 

concentration in solution is calculated. Instrument software can correct for 

background light subtraction. 

4.3.3.1. Method

EAM 4.6 Inductively Coupled Plasma-Atomic Emission Spectrometric 

Determination of Cadmium and Lead Extracted from Ceramic Foodware

4.3.4. Microwave Digestion

Homogenized food samples are added to an inert vessel with concentrated 

acid, the vessel is closed to prevent contamination and/or sample loss, and the 

food-acid mixture is heated by microwave radiation. Temperature is 
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programmed and computer controlled; typically, a linear rise in temperature 

over a set period of time to a predetermined temperature and then held at that 

elevated temperature (~200 °C) before cooling. The acid and heat combination 

dissolve the food matrix so that the analyte of interest resides in solution. For a 

nitric acid digestion, carbohydrates typically digest around 140 °C, proteins 

around 160 °C and lipids around 180 °C. Hydrogen peroxide is usually added 

to provide an oxygen source so that dissolved carbon is liberated as CO2, 

reducing unwanted matrix components from the test solution. Solutions are 

then diluted with water to reduce acid concentration for a suitable test solution.

4.3.5. Multi-Element, Simultaneous Sequential/Quantitative Analysis of Food 

and Feed by ICP-AES

As described, ICP-AES can be used for multiple elements and application to 

food matrices often requires microwave digestion. 

4.3.5.1. Methods

A. EAM 4.4 Inductively Coupled Plasma-Atomic Emission Spectrometric 

Determination of Elements in Food Using Microwave Assisted Digestion

B. AOAC 2011.14 Calcium, Copper, Iron, Magnesium, Manganese, 

Potassium, Phosphorus, Sodium, and Zinc in Fortified Food Products. 

Microwave Digestion and Inductively Coupled Plasma-Optical Emission 

Spectrometry (Available in AOAC Methods Manual)

4.3.6. Multi-Element, Simultaneous Sequential/Quantitative Analysis of 

Foods and Feed by ICP-MS

When compared to ICP-AES, inductively coupled plasma mass spectrometry 

(ICP-MS) has lower detection limits, but higher operating costs. Samples are 

introduced to the ICP in the same way as ICP-AES. Ions at atmospheric 

pressure are entrained into a high vacuum mass spectrometer through a 

series of small, cone-shaped orifices downstream in the plasma. Once inside 

the mass spectrometer, ions are focused, separated according to their massto-charge ratio (m/z) and counted. Each element has a known set of stable 

isotopes, e.g., 75As+ is measured at m/z 75. Test solution concentrations are 

typically determined using external calibration standards. Interferences are 

overcome by either kinetic energy discrimination using a helium filled collision 

cell, chemical resolution using ion-molecule reactions in a reaction cell, or by 

high resolution instrumentation. ICP-MS can also be combined with 

chromatographic separations where different molecular forms are temporally 

separated and then quantified individually, e.g., inorganic mercury separated 

from methylmercury. 
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4.3.6.1. Methods

A. EAM 4.7 Inductively Coupled Plasma-Mass Spectrometric Determination 

of Arsenic, Cadmium, Chromium, Lead, Mercury, and Other Elements in 

Food Using Microwave Assisted Digestion

B. EAM 4.8 High Pressure Liquid Chromatographic-Inductively Coupled 

Plasma-Mass Spectrometric Determination of Methylmercury and Total 

Mercury in Seafood

C. EAM 4.10 High Performance Liquid Chromatography-Inductively 

Coupled Plasma-Mass Spectrometric Determination of Four Arsenic 

Species in Fruit Juice

D. EAM 4.11 Arsenic Speciation in Rice and Rice Products Using High 

Performance Liquid Chromatography-Inductively Coupled Plasma-Mass 

Spectrometric Determination

E. EAM 4.12 Inductively Coupled Plasma - Mass Spectrometric 

Determination of 18 Elements in Bottled Water (draft available from 

CFSAN ORS)

F. EAM 4.13 Inductively Coupled Plasma - Mass Spectrometric 

Determination of Iodine in Food Using Tetramethyl Ammonium 

Hydroxide Extraction

5. References

A. (1989). Recommended dietary allowances (10th ed.). Washington DC: National 

Academy Press.

B. (2001). Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, 

Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, 

Vanadium, and Zinc. Washington DC: National Academy Press.

C. Compliance Program Guidance Manual CPG 7304.019 04019A Toxic Elements 

in Food and 04019B Toxic Elements in Foodware (09/30/10). (accessed 

05/04/23)

D. 7371.003 Feed Contaminants Program Animal Food Field Programs 

(sharepoint.com). 

E. Draft Guidance for Industry: Action Levels for Lead in Food Intended for Babies 

and Young Children (January 2023). (accessed 05/21/23).

F. Draft Guidance for Industry: Action Levels for Lead in Juice (April 2022). 

(accessed 05/21/23).
FOOD AND DRUG ADMINISTRATION

OFFICE OF REGULATORY AFFAIRS

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ORA Lab Manual Vol. IV Section 6 - Elemental Analysis Orientation and 

Training (IV-06)

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G. Closer to Zero: Reducing Childhood Exposure to Contaminants from Foods

(03/03/23). 7. Closer to Zero: Reducing Childhood Exposure to Contaminants 

from Foods (03/03/23). (accessed 05/21/23) 

H. U.S. Food and Drug Administration, Office of Enforcement.GUID-000173 CPG 

Sec 545.400 Pottery (Ceramics); Import and Domestic - Cadmium 

Contamination | FDA (Rev. 1995, November 29)(accessed 03/20/23). 

I. U.S. Food and Drug Administration, Office of Enforcement. CPG Sec 545.450 

Pottery (Ceramics); Import and Domestic - Lead Contamination | FDA

Rev.2005, November 29). (accessed 03/20/23)(CPG 7117.07), pp. 296-298.

J. U.S. Food and Drug Administration, (current edition). Compliance policy guides, 

sec. CPG Sec. 540.600 Fish, Shellfish, Crustaceans and other Aquatic Animals 

- Fresh, Frozen or Processed - Methyl Mercury | FDA (accessed 03/20/23), 

February 2007. .

K. U.S. Food and Drug Administration, Compliance & Enforcement (Food) Center 

for Food Safety and Applied Nutrition, Food Compliance Programs. 

(10/11/2022). (2001, May 25). 

L. CVM Compliance Programs, 7371.003 Feed Contaminants Program, 

https://www.fda.gov/animal-veterinary/compliance-enforcement/cvmcompliance-programs (accessed 02/03/23).

M. California Proposition-65, Lead, California Code of Regulations, Title 22, 

sec.12805 (b).

N. Carrington, C. and Bolger. P. M. (1992). Regulatory toxicology & pharmacology, 

16, 265.

O. Friberg, L., Piscator, M., and Nordberg, G. (Eds.). (1971). Cadmium in the 

environment. Boca Raton, FL: CRC Press.Gould, J. H., Capar, S. G., Jacobs, R. 

M., Plunkett, R. (1988). A quick color test to detect lead release from glazed 

ceramic and enameled metalware. Anaytical Letters, 21, 2145- 2154.

P. Dolan, S. P., Capar, S. G., Jacobs, R. M., Plunkett, R. J., Hawkins, G. S. (1994). 

Sensitivity of the quick color test for indicating lead release from ceramicware. 

Journal of Association of Official Analytical Chemists, 77, 454-457.

Q. Gould, J. H., Capar, S. G. (1990). Comparison of lead check swabs to AOAC 

method for determination of lead in ceramic glazes. Laboratory Information 

Bulletin, LIB No. 3445 6(2), 1-3.

R. Dolan, S. P. (1994). Rapid abrasion test to indicate lead on the surface of 

ceramicware. Journal of Association of Official Analytical Chemists International, 

77, 718-722.
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07 Nov 2023

Title: 

ORA Lab Manual Vol. IV Section 6 - Elemental Analysis Orientation and 

Training (IV-06)

Page 14 of 17

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S. Capar, S. G. (1998, August). Ceramic foodware lead screening using test kits. 

Laboratory Information Bulletin, LIB No. 4127, 14, 1-8.

T. Capar, S. G., Anderson, D.L., Hughes, D. D., Jacobs, R.M. (1996). Identification 

of lead solder on a metal can seam. Laboratory Information Bulletin, LIB No. 

4041, 12(12).

U. U.S. Food & Drug Administration, Environmental Contaminants in Food 

(01/24/2023) (accessed 08/29/223). 

V. U.S. Food & Drug Administration, Center for Food Safety and Applied Nutrition. 

(2000, February/March). Ask the regulators, emerging international contaminant 

issues: development of Codex Alimentarius standards to address these issues. 

Food Safety Magazine (reprinted from February – March 2000 issue).

W. Federal Register. (1999, July 8). FDA-State administration of entry/exit 

inspection and quarantine of China (SAIQ) memorandum of understanding, Vol. 

64, No. 144, 40875.

X. FDA/EPA 2004 Advice on What You Need to Know About Mercury in Fish and 

Shellfish, (07/02/2019) (accessed 08/29/23). 

Y. Advice about Eating Fish (09/28/2022) (accessed 08/29/23)

Z. U.S. Food & Drug Administration, Center for Food Safety and Applied Nutrition. 

FDA Total Diet Study (TDS). (07/15/2022) (accessed 08/29/2023). 

AA. Additional FDA references:

Laboratory Methods (Food)

Foods Program Compendium of Analytical Laboratory Methods 
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6. Procedure

6.1. Sample Preparation

6.1.1. Food Edible Portion

6.1.2. Food Homogenization

6.1.3. Digestion and Separation

6.1.4. Contamination Control

6.2. General Analytical Operations

6.2.1. Safety

6.2.2. Terminology

6.2.3. Uncertainty

6.2.4. Special Calculations

6.2.5. Reference Materials

6.2.6. Performance

6.2.7. Typical Element Concentrations

6.3. Analytical Methods

See Analytical Methods section of EAM. 

7. Glossary/Definitions

A. See Glossary section of EAM.

8. Records

Refer to local Quality Management System requirements to determine the 

necessary records needed to meet accreditation and quality control 

expectations
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9. Supporting Documents

Refer to local Quality Management System requirements to determine the 

necessary Supporting Document needed to meet accreditation and quality 

control expectations

Document History

Revision

#

Status*

(D, I, R) Date Author Name and Title Approving Official Name and Title

1.2 R 09/01/2005 LMEB LMEB

1.3 R 02/06/2012 LMEB LMEB

1.4 R 02/14/2013 LMEB LMEB

02 R 06/30/2020 LMEB LMEB

03 R SEE QMIS MICHAEL WICHMAN, SPC

ORA/ORS/OHAFLO/HAFSS LMEB

* - D: Draft, I: Initial, R: Revision
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ORA Lab Manual Vol. IV Section 6 - Elemental Analysis Orientation and 

Training (IV-06)

Page 17 of 17

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Change History

Revision 

# Change

1.2

Table of Contents – Titles changed for 6.1.4, 6.2.2, 6.3.1, deleted 6.3.3, Arsenic 

(total) and Selenium (total) in Food, 6.3.4 now 6.3.3 and 6.3.4 now 6.3.5

Added Section 6.6.

Revised Section 6.1; method cited in 6.3.2 A.; method changed in Section 6.3.5 A.

1.3

Table of Contents – Titles changed for 6.2, 6.2.2, 6.2.4., & 6.6; deleted 6.3

6.2 – title changed; “novice” deleted from first sentence

6.2.2 – changed to Qualitative analysis by XRF & added Method

6.2.3 A. & C. – changed to GFAAS, GFAAS method & references

6.2.4 – changed to ICP-OES and changed method reference in A.

6.4 Appendix – changed to 6.2.3 & GFAAS; answers to questions 1., 2., & 6 changed 

to GFAAS Manual or EAM 4.2

1.4 Header – Division of Field Science changed to Office of Regulatory Science

02

• Removed references to technology no longer used by FDA in elemental analysis

• Added technology and methods currently used by FDA in elemental analysis

• Linked sections need by analysts for elemental analysis training the FDA 

Elemental Analysis Manual 

• Added applicable Compliance Program references

• Added internal FDA references

• Reformatted to the new LM format

03 • All references and links confirmed or updated as needed. Reformatted. No other changes 

made.

Attachments

None