(Note: in the case of some individuals may dullness and inability of clear thinking mean quite unspecific symptom, which does not depend at all with increased content CO2 in an environment)
(Kumbuka: Katika kesi ya Watu na baadhi may Kutoweza ubutu wa kufikiri wazi kabisa maana unspecific dalili, ambayo hayategemei wakati wote na maudhui ya Ongezeko la CO2 katika mazingira)