National Institute of Standards and Technology

Dietary Supplement Laboratory Quality Assurance Program

100 Bureau Drive, Stop 8392

Gaithersburg, Maryland 20899-8392

E-mail: QAPHUB@nist.gov

Website: https://qa-hub.nist.gov

January 21, 2022

Dear Colleagues,

Thank you for your interest and/or past participation in NIST Quality Assurance Programs (QAPs). A call 

for participants in Exercise 1 of the Dietary Supplement Laboratory Quality Assurance Program (DSQAP)

is now open. DSQAP is designed to assist laboratories in the development and validation of new 

analytical methods, in improving the quality of their analytical measurements, and in supporting 

compliance with a number of federal regulations enforced by the US FDA, USDA, and other international 

bodies. Exercise 1 will offer opportunities for participants to measure mass fractions of nutritional and 

toxic elements, water- and fat-soluble vitamins, phenolic content, contaminants, proximates, and 

withanolides in dietary supplement ingredients and finished products. There will also be a focus on the 

compositional testing of kelp materials, sponsored by World Wildlife Fund. Laboratories may elect to 

participate in some or all studies (e.g., only nutritional elements and water-soluble vitamins) or report 

only selected analytes (e.g., calcium and sodium, but not iron and potassium), as applicable to the work 

done in their laboratories.

Participation in DSQAP is free of charge with the support of NIH-Office of Dietary Supplements (ODS), 

although participants will be required to pay for the cost of sample shipment by providing NIST with a 

shipping account number using UPS, FedEx (including TNT), or DHL. International participants must 

provide an import shipping account number, if applicable. Participants are responsible for all incurred 

shipping charges, including those that may result from shipments being returned to NIST because of 

customs clearance issues. In no cases are participants paid to participate in DSQAP.

Instructions for sign up for new and existing NIST QAP participants are attached. Registration will open 

on January 24, 2022 and will close on March 4, 2022. Samples will be distributed in late March/early 

April 2022.

We hope that within this exercise you will find studies that are of interest and use to your laboratory. 

Future DSQAP studies may address additional areas such as authenticity and microbial contaminants, as 

needs are identified. If you have any suggestions for studies or would like more information regarding 

DSQAP and other NIST QAPs, please send your request to QAPHUB@nist.gov or visit https://qa.nist.gov.

Please let us know if you have questions. We look forward to your participation in this and future DSQAP 

exercises.

Best regards,

DSQAP Team
NIST Dietary Supplement Laboratory Quality Assurance Program Exercise 1 - Spring 2022

Dietary Supplement Laboratory Quality Assurance Program (DSQAP)

Exercise 1 – Spring 2022

Compositional Testing of Kelp

With the rapid growth of the global seaweed and kelp farming industry in particular, reference materials and 

appropriate analytical techniques are critical for the characterization of product composition. Kelp has been a 

traditional part of the diet in Asian cultures and is increasing in popularity among the global population for 

human consumption and animal feeds. The goals of these studies are to determine discrepancies across the 

industry, narrow focus to the methodologies that need improved standardization, and connect the farming 

industry with the analytical testing community. Studies including kelp samples are sponsored in part by 

World Wildlife Fund (WWF). Laboratories can sign up for any of the studies for which they have capabilities and 

interest.

Nutritional and Toxic Elements

Kelp may serve as an important source of essential nutrients, but accumulation of elements depends on both 

the bioavailability of these elements in the environment and the uptake capacity of each species of these 

brown algae. Besides varying between species, elemental concentrations in kelp may vary by season, growing 

stage, depth of cultivation, location of origin, and genetics. This study will compare measurements of selected 

nutritional elements and toxic elements. Some elements are essential for the body to function properly, but 

both deficiency and excess can lead to potential negative health outcomes. For example, high sodium intake 

and iodine disorders are still major worldwide public health issues. Consumers limiting Na intake to lower 

health risks combined with the increased use of designer salts has led to decreased iodine intake, as iodized 

salt has traditionally been a common source of iodine in most diets. Kelp accumulates iodine and thus could 

be a potential source of iodine for consumers. However, these macroalgae may also uptake toxic elements. 

This may result in contamination and consumption of contaminated foods, which can cause illness, 

impairment, or, at very high doses, death. Participants will be asked to use their laboratory’s routine 

measurement technique(s) for the determination of the selected elements of interest in kelp.

Analytes

Ca, Cr, I, K, Mg, Na, S, Se

tAs/iAs, Cd, Pb, Hg, Cu, Zn

Samples

Kelp

Water- and Fat-Soluble Vitamins

Kelp has been studied for its vitamin composition and both vitamin B3 and vitamin K1 are commonly found at 

nutritionally significant levels. Vitamin B3 (also known as niacin) is involved in cellular metabolism, cell 

signaling, DNA production and repair, and has antioxidant properties. Symptoms of niacin deficiency include 

skin rash or discoloration, constipation or diarrhea, fatigue, and memory loss. Even though niacin deficiency 

is rare in most Western countries, people who are malnourished are at risk. Vitamin K is a group of 

compounds (vitamin K1 and K2) that play a key role in clotting of blood, preventing excessive bleeding. 

Vitamin K deficiencies are rare in adults but are very common in newborn infants, and a single injection of 

vitamin K for newborns is standard. Vitamin K has also been used to counteract an overdose of the blood 

thinner coumadin. Vitamin K1 is the form obtained from leafy greens and some other vegetables, and reports 

suggest that cis- and trans- isomers of vitamin K1 may have different bioavailabilities. Participants will be 

asked to use their laboratory’s routine measurement technique(s) for the determination of vitamin B3 (as 

niacin and niacinamide) and vitamin K1 (as total phylloquinone, cis-phylloquinone, and trans-phylloquinone) 

concentrations in kelp.

Analytes

Vitamin B3, Vitamin K1

Samples

Kelp
NIST Dietary Supplement Laboratory Quality Assurance Program Exercise 1 - Spring 2022

Total Phenolic Content

Polyphenol-rich diets have been linked to many health benefits. Polyphenols are a class of bioactive 

compounds found in kelp, which may contribute bioactive profiles. Although many approaches exist for 

determination of total phenolic content, this study will focus on the measurement of gallic acid and gallic acid 

equivalents in several different kelp materials. Participants will be asked to determine gallic acid and gallic 

acid equivalents in kelp and green tea. This study will also include a component for multi-laboratory validation 

of the AOAC Official First Action Method 2017.13 for the measurement of total phenolic content and is also 

sponsored in part by the National Institutes of Health Office of Dietary Supplements (NIH-ODS).

Analytes

Gallic acid, gallic acid equivalents

Samples

Kelp, Green Tea

Proximates, Dietary Fiber, and Starch

Variations between species, growing season, or growth stage may affect the nutritional make up of kelp. 

Proximates make up the macronutrient profile of foods and their measurement is critical for crop designation 

and health, as well as understanding the impact of macronutrient consumption on human health. Fiber and 

starch are also important product characteristics for both nutritional and industrial use aspects. Participants 

will be asked to use their laboratory’s routine measurement technique(s) for the determination of ash, 

protein, carbohydrates, fat (crude fat and fatty acids), calories, solids, dietary fiber, and starch in kelp.

Analytes

ash, protein, carbohydrates, fat (crude fat and

fatty acids), calories, solids, dietary fiber, starch

Samples

Kelp

Organic Contaminants

Algae are known are able to take up chemical compounds in their environment, and consumer products must 

be free from high levels of harmful contaminants. Perfluoroalkyl substances (PFAS) are a class of industrial 

compounds used in a variety of processes and consumer products and exposure has become a major public 

health concern due to potential adverse health effects. PFAS are highly resistant to degradation and can 

persist in the environment and the body for years. Standardization and harmonization of analytical 

measurement techniques are essential for the detection of PFAS for consumer safety and for the association 

of PFAS concentrations with exposure sources and health outcomes. Participants will be asked to use their 

laboratory’s routine measurement technique(s) for the determination of select PFAS concentrations in kelp.

Analytes

Select PFAS Compounds

Samples

Kelp
NIST Dietary Supplement Laboratory Quality Assurance Program Exercise 1 - Spring 2022

B Vitamins in Meal Replacement Supplements

B vitamins are a group of water-soluble compounds important for maintaining good health and well-being. 

These vitamins impact energy levels, brain function, and cell metabolism as they play roles in converting food 

into energy, creating new blood cells, and maintaining healthy cells throughout the body. Vitamin B 

deficiencies have been linked to anemia, depression, fatigue, muscle weakness, and poor memory. Meal 

replacement supplements contain many nutritional compounds, including water-soluble vitamins. Products 

in both powdered and ready-to-consume forms are available on the market and have identical labeling 

requirements, but the matrix complexities and differences can pose measurement challenges for analytical 

testing laboratories. A goal for this study is to determine any discrepancies and/or analytical challenges for 

the measurements of B vitamins across the testing community, using similarly promoted consumer products 

with different sample preparation requirements. Participants will be asked to use their laboratory’s routine 

measurement technique(s) for the determination of thiamin (B1), riboflavin (B2), niacin (B3), 

pantothenic acid (B5), vitamin B6, biotin (B7), folic acid (B9), and Vitamin B12 concentrations in both liquid and 

powdered meal replacement formulations. This study is sponsored in part by the National Institutes of Health 

Office of Dietary Supplements (NIH-ODS).

Analytes

thiamin (B1), riboflavin (B2), niacin (B3),

pantothenic acid (B5), vitamin B6, biotin (B7),

folic acid (B9), vitamin B12

Samples

Liquid and Powdered Meal Replacement 

Formulations

Withanolides in Ashwagandha

Ashwagandha (Withania somnifera, fam. Solanaceae) is highly regarded in traditional medicines and 

increasingly popular as a dietary supplement. Along with a high alkaloid content, ashwagandha contains 

withanolides, which are naturally occurring plant-based steroids that are purported to improve cognitive 

function and have anti-inflammatory and immune-boosting properties. Reference methods and materials are 

needed to substantiate product labels and investigate health claims. A goal for this study is to provide 

ashwagandha materials to determine any community discrepancies and/or analytical challenges in the 

analysis of withanolides. This study will also include a component for multi-laboratory validation of the

AOAC Official First Action Method 2015.17 and move towards the development of an ashwagandha reference 

material which will allow the industry to meet the requirements of regulatory agencies. Participants will be 

asked to use their laboratory’s routine measurement technique or the AOAC method, if possible, for the 

determination of withanoside IV, withanoside V, withaferin A, 12-deoxywithastromonolide, withanolide A, 

and withanolide B in ashwagandha root and extract materials. This study is sponsored in part by the National 

Institutes of Health Office of Dietary Supplements (NIH-ODS).

Analytes

withanoside IV, withanoside V, withaferin A,

12-deoxywithastromonolide,

withanolide A, withanolide B

Samples

Ashwagandha Root and Extract
NIST Dietary Supplement Laboratory Quality Assurance Program Exercise 1 - Spring 2022

Registration Instructions

For New NIST QAP Participants

To participate, first request an account by navigating to https://qa-hub.nist.gov and clicking Request new 

account. Your account request will be approved by a program administrator, after which you will receive 

an automated confirmation email with login information. Please modify the temporary password 

immediately upon logging in to the system and confirm or update your contact information on the My 

account page. All participants are required to provide shipping account information (e.g., FedEx/TNT, 

UPS, DHL), to which the cost of sample shipment will be charged. Your account will not be approved until 

a valid shipping account is provided. Next, log in to your account at https://qa-hub.nist.gov. Click Enroll 

to upcoming exercises on the top menu or scroll to the bottom section under Upcoming exercises and 

click the blue button for Apply for exercises. and select the studies of interest to your laboratory, then

click the blue button for Save and confirm. Your participation request will be approved by a program 

administrator, and you will receive an automated confirmation email. Study selections can be modified 

at any time up until the close of the registration period.

For Existing NIST QAP Participants (DSQAP, HAMQAP, and/or CannaQAP)

Navigate to https://qa-hub.nist.gov and click Reset your password. Enter the email address associated 

with your registration on a previous QAP site, and click the blue Submit button. You will then receive an 

automated email with instructions to reset your password. Please confirm or update your contact 

information on the My account page (access via the black menu bar) using the red My laboratory settings 

tab at the top. To participate, click Enroll to upcoming exercises on the top menu or scroll to the bottom 

section under Upcoming exercises and click the blue button for Apply for exercises. and select the studies 

of interest to your laboratory, then click the blue button for Save and confirm. Your participation request 

will be approved by a program administrator, and you will receive an automated confirmation email. 

Study selections can be modified at any time up until the close of the registration period. All participants 

are required to provide shipping account information (e.g., FedEx/TNT, UPS, DHL), to which the cost of 

sample shipment will be charged. Your participation request will not be approved until a valid shipping 

account is provided.