https://ehtrust.org/cellphones-and-your-blood-what-you-need-to-know/

A New Study: Blood Cells Clumping in Real Time 

Dr. Robert Brown, Vice President of Scientific Research and Clinical Affairs for the Environmental Health Trust and a diagnostic radiologist with extensive experience evaluating blood flow using diagnostic ultrasound, and his colleague Barbara Biebrich, a senior ultrasound technologist with decades of experience performing vascular ultrasounds, decided to test whether ultrasound could detect and display rouleaux blood clumps forming in real time, in a healthy volunteer. 

Hypothesis: ultrasonography can document dynamic in vivo rouleaux formation due to mobile phone exposure https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2025.1499499/full