Officials at Wisconsin Poison Control are advising parents to keep at-home COVID-19 test kits away from kids because they could contain a harmful, toxic substance.
This comes as more than 50 million households recently received free at-home COVID-19 tests from the federal government, according to Dr. Tom Inglesby, senior advisor for the White House COVID-19 response team.

The substance of concern is sodium azide which is in the reagent liquid used to trigger the chemical reaction that detects the presence of coronavirus. The types of test kits vary, but they generally contain a swab, testing card and an extraction vial containing the reagent liquid.
When the liquid is swallowed, the sodium azide in it can cause a headache and lower blood pressure. In large amounts, it can cause seizures, according to the poison control center.
Dr. Nicholas Kuehnel, medical director for quality and safety for UW Health Kids, reminds parents that it is always important to read the instructions.
If your child swallows that liquid or it touches their skin, have them drink lots of water to flush it out or wash the area with soap and water.
Call poison control if a negative reaction continues.
To prevent accidental poisonings from the COVID-19 home test kits, poison control centers recommend the following tips:
- Store the kit “up and away,” out of the sight and reach of children and pets.
- Leave the kit sealed until needed and throw it away immediately after use.
- Make sure to read and follow the instructions on the package before using.
Poison Control can be reached online or by calling 1-800-222-1222.