“Not Detected” on a Pet Food Lab Report Does Not Mean Absolute Zero
PARTNER Editorial Team“Not detected,” sometimes abbreviated ND, needs to be read with the laboratory method and reporting limit. It is not a statement that absolutely none of a substance exists in every bag. It also does not tell you which other substances were tested.
When a brand shares a laboratory screenshot, look for the complete context before interpreting it as an all-purpose safety guarantee. The most useful report answers a specific question about an identified sample.
A reporting limit changes the meaning
Laboratory methods have limits to what they can reliably detect or report. In an explanation of food testing, the FDA described how establishing method detection limits changed whether very low concentrations were reported as detectable.
That FDA example concerns chemical testing in foods, not a safety threshold for your dog or cat and not a finding about PARTNER. It illustrates the general reporting issue: a result belongs with its method, limit and sample. Removing those details can make a modest statement sound absolute.
“Below a reporting limit” and “measured at a stated concentration” also require different interpretation. Ask the laboratory or manufacturer what the notation means on that report rather than assuming every dash, less-than sign or ND uses the same convention.
Five things to find before comparing results
On a small screen, swipe the table to see all columns.
| Report detail | Why it matters to the question |
|---|---|
| Sample identity | Connects the result to a food, ingredient or production lot |
| Named analyte | Identifies the specific substance tested |
| Method and limit | Shows how detection or reporting was defined |
| Units and basis | Makes clear what the number refers to |
| Date and report scope | Helps distinguish one sample from an ongoing program |
A report for an ingredient is not automatically a report for the finished meal. Likewise, a result for an identified lot should not be retold as a finding about all past and future production. Ask what sampling and quality-control program supports any broader claim.
A hypothetical screenshot, read carefully
Imagine a picture showing “ND” beside one chemical name, with the sample identification cropped away. You cannot tell whether it describes the bag you own, the finished recipe or a raw material. Nor can you tell whether the test was sensitive enough for the question being asked.
The appropriate response is to request the complete report and explanation. It is not to declare the product unsafe, or to declare it free of all contaminants. Missing context prevents either conclusion.
Keep the conclusion as narrow as the evidence
Ask the brand: What was sampled? Which substances were measured? What do the limits mean? Which batches does this information cover? What other controls support the claim being made?
Our lot-code guide explains how to identify your package, while the AAFCO statement guide addresses a different kind of nutritional evidence. This article does not claim that a particular PARTNER laboratory report exists or that any test establishes universal safety. It helps you read the evidence that is actually supplied.
Published by PARTNER Editorial Team for general education. Your veterinary team can advise on your pet’s individual health and feeding needs.