Rest your head on natural non-toxic pillows of your choice.
Both for our health and the health of the planet, it is wise to avoid sleeping with bed pillows that are made from synthetic materials such as polyester or microfiber.
These materials are typically made with polyurethane and/or treated with flame retardants or other unhealthy chemicals. These toxins will continue to off-gas for many months. That is not healthy! People who suffer from allergies or chemical sensitivities will be more affected but it does impact the quality of sleep of all of us.
If you can, try to switch to a natural alternative and observe how it improve your sleep and your health.