Medical science is continually playing out a shell game, when it comes to identifying specific environmental causes of disease. The studies that link heavy metals, and other environmental pollution to conditions like leaky gut simply will not be properly conducted or funded.
I personally suffered from Candida and leaky gut, I even had blood results high in lead and aluminum, yet the CDC wont even acknowledge that these conditions exist even though they are fairly common.
Another problem is the single cause presumption, science cannot test for the multitude of variables that would explain why one person exposed to a certain amount of pollution will develop a condition, while another person will not.
Mercury in shots, amalgams, and other environmental sources may only act as an adjuvant that along with a number of other factors work to increase ones susceptibility to such conditions. My hair analysis showed I was high in aluminum, cadmium, manganese, and lead, as well as deficient in many trace minerals. It is rare that just one element would results in the development of these chronic conditions
Personally I had Mercury shots growing up, mercury amalgams, drank fluoridated water, ate foods with aluminum as an ingredient, ate GMO, drank bovine growth hormone pasteurized milk, worked around formaldehyde treated lumber, PCB electrical components, etc. When one is under the influence of sooo many negative conditions simultaneously then WHO is to say exactly what is the primary cause when at 22 years old , I became stricken down with a mystery illness.
Comprehensive testing of segments of the population by government organizations could be done, and would help to shed some light on the subject. It cost 70 million dollars for a fighter jet and our government pays for hundreds in order to protect us from harm, and yet they absolutely refuse to spend a fraction of that to investigate why millions of people are being attacked from the inside out by these mysterious conditions. Its a tragedy.