If I am understanding it correctly…

• They eat tuna often.
• They never noticed anyone that cannot draw (separate) conclusions that:
  • [were] baseless
  • made little sense
• Evidence of heavy metal (features) resembled natural pathways.
• Worrying about high lead or cadmium [in food products? doesn’t make sense].

Even laid out like that, it is still confusing. However, I think their gist is that:

1. they think heavy metals’ effects [on humans] are indistinguishable from what happens normally
2. no one can draw conclusions about heavy metals’ [effects on humans] that have basis
3. they think worrying about heavy metal contamination in food is stupid and people shouldn’t worry about it