While I think there is a conversation about chemical risks in sunscreen and their bio-availability in the bloodstream and thus potential to act e.g. as an endocrine disruptor, There are also much LESS biologically active agents like titanium dioxide and zinc which can form a physical barrier, and make up part of a sunscreen to help reduce the chemical risk.

I think blogs talking up the risk side have a responsibility to also talk the other side. Not wearing sunscreen can be very high risk, incur lifetime and life-threatening consequences. Not being exposed to the sun is not risk-free either.

I think all things relating to cancer are a balancing act. There is the risk of an as-yet misunderstood chemical exposure. There is the understood risk of melanoma. There is the risk in avoidance of sunlight: of lack of Vitamin D and its effect on overall health, bone density, depression. You have to weigh up risks. The risk is not equal over your lifetime or to all people of all genetics. The risk can be altered by other medications you have to take for higher risks.

I take the advice of the Australian Cancer Council and my skin specialists into account weighing up my sun exposure and use of sunscreen. I have already had BCC removed, by both surgery and freezing. I have an annual checkup. I have had biopsies on removed spots.

Cancer risk has a strong relationship to childhood exposure and burn. Not total, lifetime burden plays its part as does genetics. Every Australian should know the risk is there, it's inculcated from childhood onward. Slip/Slop/Slap. No Hat, No play.

Chemical exposure risk demands huge epidemiology, and right now the numbers don't tell a compelling story that demands we stop using any sunscreen. We already have had (in the last 4-5 decades) withdrawal of specific chemicals from sunscreen: Cinnamate was withdrawn in the 70s. Benzine contamination is a high risk, especially in the liquid sprays. Cinnamate was a known endocrine disruptor. Benzine is a cancer risk all of it's own.

Sub-standard testing and over-rating of the SPF equivalency is a big risk too. One testing agency shared by a lot of companies has had it's processes reviewed after SPF50 was found to be more like SPF10 or less for several brands including cancer-council supported brands. Testing is pretty basic: they basically apply the sunscreen to volunteers in patches and try to give them burns under a UV lamp. Talk about risky behaviour!

Correlation is not causation. RCTs of sunscreen show 30-50% reduction in melanoma risk.