Research published in 1994 (“Experimental studies on the influence of millimeter radiation on light transmission through the lens” Klin Oczna. 1994 Aug-Sep; 96(8-9):257-9) showed that rats exposed to millimetre wave radiation for only 56 days developed changes in the lens of their eyes.
The wave length used was 5.6 mm (53 GHz). The power output was 10 milliwatts/cm2 (100,000,000 microwatts/m2)
The rats’ exposure in this study is higher than the applicable time averaged standard in NZ (NZS 2772.1:1999) which would allow for a maximum (time averaged) exposure of up to 1 W/cm2 (10 million microwatts per square metre) for the general public for 53 GHz. (It is lower than the peak public exposure limit of 10 billion microwatts per square metre.)
The authors, Prost M, Olchowik G, Hautz W, Gaweda R, conclude the abstract for their study by stating that “radiation in millimetre range can induce changes in the lens, predisposing to cataract development.”
The abstract for the study may be accessed via https://www.ncbi.nlm.nih.gov/pubmed/7897988