Frequently Asked Questions

Thank you for visiting our website. Below are answers to our most frequently asked questions.
If you can't find an answer here, please contact us via email.

We are happy to help.



Q: Is your laboratory accredited?
A: NP Analytical Laboratories is ISO 17025:2017 for biological and chemistry testing. See our Resources page for more details. NP Analytical is also accredited by the State of Florida and by USDA for testing of salt, moisture, protein, and fat in meats.


Q: Are you a GLP laboratory? 
A: GLP guidelines generally apply to pharmaceutical testing and are not typically used by food and feed testing laboratories. However, NP Analytical maintains an extensive quality program based on many of the principles incorporated into GLP guidelines. Our comprehensive quality program is based on qualified personnel, validated and documented test procedures, independent proficiency testing, long-term record retention, automated sample tracking, and an independent quality unit.


Q: Do you have labs in other locations? 
A: We maintain a single centrally located laboratory in St. Louis, MO. This allows us to maximize our efficiency while concentrating all available expertise at one site. Samples can reach us overnight from most locations around the world.

Q: What if I can’t find one of the tests I need in your fee schedule or on this web site? 
A: NP Analytical offers a wide range of chemical and microbiological testing and it isn’t practical to list all tests in our fee schedules. Call or email us to request any assay you are unable to locate. If we can’t meet your needs, we will gladly suggest other laboratories that might be able to fulfill your request. We also may, with your acknowledgment, subcontract certain tests when we can meet most, but not all, of your needs.



Q: Where do I send samples for testing? 
A: Samples should be sent to: NP Analytical Laboratories, c/o Sample Entry, 824 Gratiot, St. Louis, MO, 63102. Download a Sample Submission Form.


Q: Can I get priority service? 
A: If you need priority service, please contact us to discuss.


Q: How much sample do I need to send? 
A: The size of sample you will need to provide depends on which tests you request and we are happy to discuss your sampling and sample size requirements. Many of our tests require 10g or less per test, but a few require more. Most importantly, be sure your sample is large enough to be representative of the product or ingredient you are testing. If you are sampling a bulk material (grains, premixes, powders, etc.) avoid taking a sub-sample from off of the top or bottom. Mix before sampling, if possible, and composite several small sub-samples. If you are sampling a packaged product, submit multiple packages selected at random from the batch to be tested. Proper sampling is the key to meaningful test results.


Q: Do I need to include a purchase order with my samples? 
A: We do not require purchase orders, but they are often helpful for linking invoices to samples that were tested. You should receive an invoice by the second week of the month following completion of testing. Please enclose complete billing information with your order, including name, address, and phone number of billing contact. NP Analytical Labs reserves the right to require advance payment prior to initiating testing. Download a Sample Submission Form.



Q: I have a question regarding my test results or services provided by NPAL. Who do I contact? 
A: We welcome your comments, questions, or concerns regarding any service provided by NP Analytical Laboratories. Please call us at 800-423-6832 or 314-982-1310 or email us. We value your input as we look for ways to better meet the needs of our valued customers.


Q: Can you tell me the method precision for the tests I am requesting? 
A: We continually evaluate the precision of methods used in our laboratory and will share that information on request. Method precision, however, depends on a variety of factors such as analyte concentration and matrix. As a result, we cannot give assurance that our precision data will necessarily be relevant to your samples.


Q: Can I get a copy of the method you use? 
A: Detailed copies of our methods are proprietary and are not available to our customers. We can, however, provide method summaries describing the principle of any method and appropriate references to compendium methods relevant journal articles.


Q: How long will my data be kept in your files? 
A: Hard copies of all raw data, including charts and chromatograms, are maintained in storage for at least five years. Electronic copies of final reports will also be retained. There may be a charge for recovery of this information from storage depending on the volume of material requested and the storage location.


Q: Can I get an electronic copy of my report? 
A: Copies can be emailed if you provide the necessary information with your sample submission. For large studies we will happily provide spreadsheet data summaries that may be transmitted electronically. These summaries are in addition to our official report. Contact us to discuss your needs.