Aluminum - Toxicology of Metals - page 340

may take some years to heal or decrease (Kaaber et al .,
1992). Itching nobulus were found in 645 children out
of 76,000 vaccines (0.8%) after both subcutaneous
and intramuscular injections. A majority of the chil-
dren (75%) had symptoms after a month duration of 4
years, and 77% of the children with nodulus showed
contact hypersensitivity to aluminum (Bergfors et al.,
2003). Sensitization has also occurred after aluminum
particles were accidentally impelled into the skin
from a compressed air pistol (Peters et al ., 1998). Tat-
tooing with aluminum silicate to create blepharopig-
mentation has resulted in a delayed-hypersensitivity
granulomatous reaction (Schwarze et al ., 2000).

Synthetic abrasive materials containing aluminum
oxide, silicon carbide, and different additives have been
used for more than 70 years (Wegman and Eisen, 1981).
Exposure to these compounds occurs during produc-
tion and when they are used for metal grinding and pol-
ishing. An increased risk for stomach cancer has been
observed in two studies (Järvholm et al ., 1982; Wegman
and Eisen, 1981), and an increased risk for lung cancer
has been observed in one (Siemiatycki et al ., 1989). Dur-
ing the past decade, studies observed an increased risk
of lung cancer (Infante-Rivard et al., 1994; Romundstad
et al ., 2001) and stomach cancer (Romundstad et al ., 2001)
associated with silicon carbide production. These work-
ers are, however, also exposed to crystalline silica. Thus,
further studies are needed to explore whether compo-
nents in synthetic abrasive materials are carcinogenic.

6.9 Coronary Heart Disease
Some studies of aluminum production workers
have observed an increased risk of coronary heart
disease (Rönneberg, 1995; Theriault et al ., 1988). This
effect might be explained by the possible association
between exposure to air pollutants and the occurrence
of coronary heart disease mediated by an infl ammatory
response that increases blood coagulation (Sjögren,
2004). It is unlikely that aluminum per se is respon-
sible for this effect, but more likely that it is due to air
pollutants in general. Slightly higher levels of fi brino-
gen were observed among aluminum smelter workers
at Söderberg pots exposed to high levels of air pol-
lutants compared with those working with prebaked
electrodes and exposed to lower levels of air pollutants
(Sjögren et al ., 2002). A high plasma fi brinogen level is
an established risk factor for coronary heart disease
(Danesh et al ., 1998). However, there are studies that do
not support the association between potroom exposure
and coronary heart disease (Romundstad et al ., 2000a).

7 OTHER ALUMINUM COMPOUNDS

Aluminum phosphide is used as a fumigant to
protect stored grain from insects and rodents. In the
presence of moisture, aluminum phosphide releases
phosphine, which is highly toxic. The fatality rate
was 59% among 195 patients admitted to a hospital
in Northwest India. The fatal dose was 1.5 g, and the
predominant clinical feature was hypotension (Singh
et al ., 1996). Two children and 29 of 31 crew members
aboard a grain freighter became acutely ill after inhal-
ing phosphine originating from aluminum phosphide.
One of the children died (Wilson et al ., 1980).

8 RECOMMENDATIONS

Aluminum is used as a coagulant in water treatment.
According to the WHO, a health-based guideline value
cannot be derived; however, practical levels based on
optimization of the coagulation process in drinking-
water plants using aluminum-based coagulants were
derived: 0.1 mg/L or less in large water treatment facili-
ties, and 0.2 mg/L or less in small facilities (WHO, 2004).
Similarly, Health Canada established an operational
guidance value of <0.1 mg/L for drinking water from
treatment plants using aluminum-based coagulants and
<0.2 mg/L for other types of treatment systems ( http://
www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/doc_sup-appui/
aluminum/aluminum-aluminium_e.html#1 ).
The occupational exposure limits for aluminum
have decreased during the last decade in many coun-
tries (Table 2). Occupational biological exposure limits
are established in some countries. Finland has a urine
biological action level (BAL) of 160

6.10 Carcinogenic Effects
Most animal studies have failed to demonstrate carci-
nogenicity attributable to aluminum powder or several
aluminum compounds (Léonard and Gerber, 1988).
The German Commission for the Investigation
of Health Hazards of Chemical Compounds in the
Work Area classifi es aluminum oxide as a category
2 carcinogen because of the unequivocally positive
results of intrapleural injections in animals (Deutsche
Forschungsgemeinschaft, 2004).
In 1987, the International Agency for Research on
Cancer (IARC) concluded that there is suffi cient evi-
dence that certain exposures occurring during alumi-
num production cause cancer of the lung and bladder
(Group 1). Pitch volatiles have fairly consistently been
suggested in epidemiological studies as possible caus-
ative agents (IARC, 1987).

mol/L)
(Kallio et al ., 1999). Germany has a biological tolerance
value for occupational exposure of 200

µ g/L (6 µ

µ g aluminum/L