Toxicity, aluminum reactivity

Although pharmacopeial biological reactivity tests for containers are good indicators of the toxicity of extractables, there are species that do not cause an acute toxic reaction but rather a chronic reaction, as is the case of phthalates (DEHP) and metallic species such as aluminum. Moreover, there are species that are extract-able from packaging materials only by action of formulation constituents and therefore are not present in the extracts obtained by conventional pharmacopeial compendia tests. 

Indicates the pore space available for water and roots influenced by soil composition (mineral content, mineral type, and organic matter) and soil texture Affects adsorption of the chemical Affects the surface area where adsorption can take place Influences partitioning and availability of chemicals Affects ability of a soil to transmit water or air Dictates the porosity of the soil Affects the form, reactivity, solubility, availability, and toxicity of some contaminants Affects the toxicity of some substances (mainly heavy metals) with binding or antagonistic mechanisms, for example, by alkaline-earth metals and aluminum Organic matter content, type, and % carbon Influences soil sorption properties for heavy metals and... 

Sodium lauryl sulfate (SLS) test6 — The SLS attacks the horny layer, making it more penetrable to chemicals and also causing inflammation. Thus, it measures both the homy layer barrier and tissue reactivity to toxic substances. Aluminum chambers are filled with 0.1 ml of 1 and 2.5% aqueous solutions of SLS. The chambers are then applied to the ventral forearm for 24 h. The reactions are scored 3 h after removal of the chambers on a scale. Those reacting strongly to the lower concentration of SLS are deemed more reactive or sensitive. 

Ga, In and T1 are much less common elements, obtained in small amounts from sulfide minerals of other elements and used only in specialized applications. The metals are less reactive than aluminum Fig. 1 shows a Frost diagram in which the much larger negative slope (negative electrode potential see Topic E5) of A1 is apparent. Thallium compounds are extremely toxic but do not normally pose an environmental hazard because they are little used. 

Aluminum ions (Al3+) have toxic effect on plants, and number of studies documented the toxic impact of Al3+ on roots,1 hypocotyls,2 and germinating pollen.3,4 It has been proposed that early effects of Al3+ toxicity at the root apex, such as those on cell division, cell extension or nutrient transport, involve the direct intervention of A1 on cell function.5 Model mechanisms of Al3+ toxicity has been proposed that A1 stimulates the NADPH oxidase and induces the generation of superoxide (02j that triggers the influx of calcium ion (Ca2+). The resultant reactive oxygen species (ROS) and cytosolic free Ca2+ concentration elevation may lead to development of phytotoxicity.6... 

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