Fourteen dogs developed neurologic signs after ingesting hydrogel from a commercial cooling pet pad. When ASPCA Poison Control identified similarities across the cases, investigators sought to determine whether a component of the hydrogel could explain the clinical presentation.
As a scientist at Cambridge Polymer Group and a co-author on this investigation, I was involved in the analytical testing that followed. The case was of particular interest to me because I am also a dog owner. The findings have been accepted for presentation at the October 2026 USAHA/AAVLD Annual Meeting. They suggest that elevated levels of acrylamide monomer, a known neurotoxin, may be associated with the neurologic signs reported in these dogs.
A Consistent Clinical Pattern
Using ASPCA Poison Control’s AnTox™ database, researchers identified 14 canine cases involving witnessed or strongly suspected ingestion of hydrogel from a commercial cooling pet pad.
Although the severity of symptoms varied, the cases shared a consistent clinical presentation.
Reported neurologic signs included:
- Seizures (7 dogs)
- Ataxia (7 dogs)
- Hyperesthesia (4 dogs)
- Fasciculations (4 dogs)
- Tremors (4 dogs)
- Disorientation (3 dogs)
- Agitation (2 dogs)
- Facial twitching (2 dogs)
Additional neurologic abnormalities reported in individual cases included coma, decreased pupillary light reflexes, depression, mental dullness, weakness, aggression, and paranoid behavior.
Vomiting was the most common non-neurologic sign, occurring in 11 of the 14 dogs. The most frequently reported laboratory abnormality was hypokalemia, which was documented in four cases.
Of the cases with known outcomes, all seven dogs recovered fully.
Developing a Hypothesis
The pattern of neurologic signs resembled findings reported in an earlier publication involving a dog and laboratory rats exposed to hydrogel from the same product line. In that investigation, however, the specific toxicant was never identified.
Based on the clinical presentation and the ingredients described in product patents, the research team considered residual acrylamide monomer a plausible candidate. The hydrogel formulation reportedly contained polyacrylamide, carboxymethylcellulose, water, and alginic acid.
Polyacrylamide is widely used in a variety of consumer, industrial, and research applications and is generally considered a safe material. Acrylamide monomer, however, is a recognized neurotoxin. Given the neurologic signs reported in these cases, determining whether acrylamide monomer was present in the hydrogel became an important next step.
Putting the Hydrogel to the Test
To evaluate the hypothesis, a cooling pad from the same product line was purchased and submitted to Cambridge Polymer Group for analysis.
Using ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS), we analyzed the hydrogel and detected acrylamide monomer at a concentration of 4.9 mg/g, or approximately 4,900 ppm.
This concentration substantially exceeded the residual acrylamide monomer levels typically expected in well-prepared polyacrylamide gel materials.
While analytical testing alone cannot establish causation, the presence of acrylamide at this concentration, combined with the observed neurologic signs, supports the hypothesis that acrylamide monomer toxicosis may have contributed to the illnesses reported following hydrogel ingestion.
Product Safety Considerations and Future Research
For manufacturers, the findings underscore the importance of material characterization, contaminant analysis, and quality control throughout the product development and production. Residual monomers and trace constituents may be present at very low levels, but identifying and quantifying them remains an important part of product safety and risk assessment.
For toxicologists, veterinarians, and regulatory professionals, investigations of unexpected adverse events often depend on both clinical observations and product analysis. In this case, recurring neurologic signs prompted examination of the hydrogel itself, leading to the detection of elevated acrylamide monomer concentrations.
Whether the elevated acrylamide monomer concentration identified in this product is unique to a particular manufacturing lot or occurs more broadly remains unknown. Additional testing and investigation will be needed to answer that question and to better understand the potential variability among similar products.
The findings discussed in this article have been accepted for presentation at the 2026 USAHA/AAVLD Annual Meeting in Madison, Wisconsin. The study was conducted by researchers from ASPCA Poison Control, Cambridge Polymer Group, and That Waterbead Lady, Inc., including Colette Wegenast, DVM, DABT, DABVT; Ashley Haugen; Rebecca Bader, PhD; Kirsten Waratuke, DVM, DABT, DABVT; Stephen Spiegelberg, PhD; and Brittany Wilt, DVM, DABT, DABVT.