I believe michaelmrose is suggesting that while microwaves are indeed a form of (electromagnetic) radiation, "low-level radiation" usually refers to low-levels of ionizing radiation, not low-power EM sources. While fwdslash might indeed be talking about low-level microwaves, there are many in my experience who think that "radiation" only means "ionizing radiation" or "atomic radiation". (Hence, "nuke it in the microwave".)

Again, in my experience, people who are aware of the distinction tend to write "More low-power microwaves" than "More low-level radiation".

For a semblance of hard numbers, "low-level radiation" gives 735 hits in PubMed Central (https://www.ncbi.nlm.nih.gov/pmc/?term=%22low-level+radiatio... ) and 338 in PubMed (https://www.ncbi.nlm.nih.gov/pubmed/?term=%22low-level+radia... ).

'"low-level radiation" microwave" gives 32 (https://www.ncbi.nlm.nih.gov/pmc/?term=%22low-level+radiatio... ) and 2 (https://www.ncbi.nlm.nih.gov/pubmed/?term=%22low-level+radia... ), respectively.

One of the latter is https://www.ncbi.nlm.nih.gov/pubmed/17886009 where you can see "low-level radiation" is used to describe microwaves: "On the radar station area, blue tits nested in high exposed nest-boxes (67,0%) and great tit occupied mainly these boxes, which were exposed to low-level radiation", where that radiation is "pulse-modulated microwave radiation of 1,200-3,000 MHz."

It's just not common.

The topic, by the way, concerns sperm counts. You write "there can be many effects". Is a change in sperm count one of them? Many people have done experiments on the effect of microwaves from mobile phones on organisms. I was at a biology conference about 25 years ago where one of the speakers talked about their research, so surely this has been tested already.

Also, radio and TV techs have been working with high-power EM for decades. There's so much power in the air around some towers that florescent tubes can glow. If low-power microwaves have an effect on fertility then we should have seen an effect on those workers long ago, yes?