GEOCHEMICAL RISK-FACTORS FOR MENTAL FUNCTIONING, BASED ON THE ONTARIOLONGITUDINAL-STUDY OF AGING (LSA) .3. THE EFFECTS OF DIFFERENT ALUMINUM-CONTAINING COMPOUNDS

Previous work on the association between total alumium (Al) concentrat ions and a measure of cognitive impairment is extended by considering the associations between this measure of cognitive impairment, not onl y with total Al, but also with turbidity and DOC both of which also co ntain Al. The multivariate, but not bivariate, analyses show that the odds of showing indications of mental impairment increase with turbidi ty but decrease with DOC, and this effect is most pronounced at a medi um pH. It is suggested that the two variables considered could account for some of the unexplained features of the association between Al co ncentrations and measures of cognitive impairment. The other associati ons, namely those with F, pH, source of drinking water (ground or surf ace) remain similar to those reported previously in this series of pap ers.