VACCINE

First International Conference on Metals & The Brain
September 20-23, 2000
From Neurochemistry to Neurodegeneration
University of Padova, Italy
Aluminum And Health
Recommendations
Aluminum is an environmentally abundant element to which we are all
exposed. The neurotoxicity of this metal has been known for more than
a century. More recently, it has been implicated as an etiological factor
in some pathologies (including encephalopathy, bone disease, anemia)
related to dialysis treatment . In addition, it has been hypothesized to be
a cofactor in the etiopathogenesis of some neurodegenerative diseases,
including Alzheimer’s disease (AD), although, despite many studies
in several laboratories in different countries, direct evidence is still, so
far controversial. Thus, examples of aluminum neurotoxicity are well
recognized-in experimental animals and in individuals with renal failure
(consequent upon aging, intoxication or renal disease) - and there
are grounds to link neurodegenerative disorders to aluminum exposure.
Furthermore, an increased concentration of Al in infant formulas and in
solutions for home parenteral nutrition has been associated with neurological
consequences and metabolic bone disease, characterized by
low-bone formation rate, respectively.
For all these reasons and on the basis of our many years of scientific
experience in this field, we propose the following recommendations as
guidelines to avoid risks due to aluminum accumulation and potential
intoxication. These recommendations are not rigid and will be updated
when relevant new scientific data is available.
General Recommendations
1. It would be valuable to define as completely as possible which patient
groups are at risk for iatrogenic aluminum loading, and under which
conditions aluminum represents a health hazard. The more complete
knowledge we have for the clinical, iatrogenic setting, the better basis
we will have to judge whether different types of aluminum exposure
are hazardous to the general population or to susceptible subgroups.
2. A provisional list of patients groups at risk of iatrogenic aluminum
loading should include, at least, people with impaired renal function,
infants, old people and patients on total home parenteral nutrition.
Where such exposure occurs, serum aluminum concentrations should
be less than 30 µg/l and possibly lower. However, further studies are
necessary.
3. Urinary aluminum is also an indicator of aluminum absorption, the
excreted Al/retained Al ratio depends on the integrity of the renal function.
4. Al may enter human body by mouth, intravenous infusions and by
environment. Specific controls have to be adopted in order to reduce
each risk of exposure.
Oral Exposure
5. Aluminum in drinking water should be less than 50 µg L-1. Silicon
is relevant to aluminum toxicity and, therefore, the water silicon concentrations
should be monitored in parallel.
6. The aluminum content should be declared in all food preparations
and pharmacological products.
7. Citrate-containing compounds appear to increase the bioavailability
of ingested aluminum. Therefore, particular care should be taken to
avoid these compounds in combination with Al-containing drugs. With
citric acid, the enhanced gastrointestinal absorption may by compensated
for by a parallel increase in urinary Al excretion, where there
is good renal function. However, it is strongly suspected from recent
simulation studies that other dietary acids (e.g., succinic and tartaric acids)
also increase Al-bioavailability but do not cause any compensatory
increase in urinary excretion. Ascorbate and lactate also significantly
enhance gastrointestinal absorption of Al, as was recently demonstrated
in animal studies.
www.laleva.cc/environment/aluminum_health.html
8. It is recommended that acidic food, e.g., acid cabbage, tomato, etc.
should not be cooked or stored in aluminum ware. In this connection,
it has been demonstrated that in the juice of acidic cabbage, cooked in
aluminum, the metal ion content is up to 20 mg/ L.
9. Individual susceptibility to aluminum has been reported by the scientific
literature. Thus, special efforts should be taken to prevent contamination
of food and beverages etc. with aluminum either directly or during
preparation, with special regard to infants, old people or individuals
with suboptimal renal functionality.
10. Magnesium depletion is considered a high risk for aluminum accumulation
especially during pregnancy and in the neonate with possible
consequent problems for normal development and growth. Magnesium
depletion is also common with aging.
11. Iron depletion is considered a high risk for aluminium accumulation,
as iron and Al share common carriers.
Parenteral Exposure
12. Aluminum in all intravenous (i.v.) fluids should be controlled monitored
and labeled. There is a general consensus that the aluminum content
of i.v. fluids used in children and adults with renal failure or undergoing
dialysis, should be as low as possible and in any case no higher
than 10 µg/L.
13. The use of parenteral nutrition fluids that are high in aluminum
should be eliminated or significantly reduced.
This document will be published in relevant scientific journals, and will
be sent to all Health Ministers of the European Community as well as
to other Public Health Authorities. (FDA, WHO etc.). For further information,
please contact Prof. P. Zatta: zatta@civ.bio.unipd.it