Quote:
Studies have found IQ reductions at 1.4 ppm (Zhang 2012); 1.8 ppm (Xu 1994); 1.9 ppm (Xiang 2003a,b); 0.3-3.0 ppm (Ding 2011); 2.0 ppm (Yao 1996, 1997); 2.1-3.2 ppm (An 1992); 2.3 ppm (Trivedi 2012); 2.38 ppm (Poureslami 2011); 2.45 ppm (Eswar 2011); 2.5 ppm (Seraj 2006); 2.85 ppm (Hong 2001); 2.97 ppm (Wang 2001, Yang 1994); 3.1 ppm (Seraj 2012); 3.15 ppm (Lu 2000); 3.94 ppm (Karimzade 2014); and 4.12 ppm (Zhao 1996)
It also varies on the individual, people involved in athletic activity drink more water than sedentary people, and also those who drink tea as a leisurely activity have potential to exceed the Chinese studies when it comes to Fluoride intake.
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Depending on what it is associated with (e.g., aluminium), F can pass through
the brain-blood barrier and accumulate in the brain and cause damage in neuronal
development and function by decreasing neural synapses, neurotransmitter
synthesis, and the number of receptors.27-29 It also impairs the central neural
system, leading to fatigue, malaise, insomnia, headache, lethargy, daze, mental
impairment, and memory dysfunction