If Prasad thought this needed more research then it needed more research. He and the people he works with have written dozens, maybe hundreds now, of reports that expose studies that lack the rigor for definitive results, have misleading endpoints, have imbalanced arms etc. I get that anything that would slow vaccines down has somehow become political and lots of people would gladly accept the pharmaceutical companies word on things. This is a blindness due to political leanings and not evidence based. If Prasad says it needs more and better data I'd put money on it needing it.
I'd like to remind people reading this that are concerned about it that there is a LOT you can do to improve the world.
If many reduced their energy consumption and material waste there would be a measurable reduction in CO2. Buy things only when you need them, reuse or find a new home for things before discarding them. Keep you tires inflated, buy efficient vehicles. Improve home insulation, consider a heat pump heating and cooling system when the time comes, etc.
Don't let this be a problem because you can't get government to force your neighbors to do it, take the initiative to lead by example.