Exposure Investigation at
Continental Aluminum
Conducted by the Michigan Department of Community Health
for the Agency for Toxic Substances and Disease Registry,
March 1 – May 31, 2004, Lyon Township, Oakland County
Outline of presentation:
• Purpose of EI, protocol development
• Results for metals (dusts and mercury)
• Results for acids and VOCs
• What about past exposure and soils?
• Conclusions
• 10-minute break
• Blood aluminum levels
• Questions/comments on report itself
Purpose of Investigation
• Public health hazard of emissions from
Continental Aluminum could not be
determined from available information.
• EI would measure air concentrations of
chemicals expected to be emitted by a
secondary aluminum smelter and during
odor events.
• EI would also collect local meteorological
data.
• MDCH compared concentrations found
to health-based Comparison Values.
Development of EI Protocol
• Determine appropriate chemicals to test for
• Determine appropriate testing methods
• Contract with analytical laboratories and
electric utility
• Make arrangements with other agencies
(ATSDR, MDEQ, Oakland Health) for
assistance
• Work with local groups
– School board, Dolsen administrators
– Citizens Advisory Workgroup
– Sampling personnel
Expected emissions:
• Metals (as airborne particulates)
• Mercury (as vapor)
• Acidic aerosols (HCl, HF)
• Volatile organic compounds (can cause
odors)
Air monitoring trailers at
Dolsen Elementary School
Air enters here
Motor draws
air through
from above
Top tips back
and filter is
placed here
High-volume pump
used for particulate
sampling
Timer set
for 24-hr
period
Dixon chart
(inside) records
steadiness of air
flow
Magnehelic
gauge readings
(before and
after sampling)
help determine
total air flow
Metals
• Tested for aluminum, barium, beryllium,
cadmium, chromium, copper, lead,
manganese, selenium, and zinc.
• Ten 24-hour filter samples taken, two
blanks also analyzed
• Test measures total metal, regardless of
form it’s in
Metals (cont’d)
• Chemicals generally not detected:
beryllium, cadmium, selenium
• Chemicals detected with some
uncertainty
: chromium, lead
• Chemicals detected with certainty
:
aluminum, barium, copper, manganese,
zinc
Metals (cont’d)
• Most concentrations fell well below the
lowest Comparison Value
– Highest reading for aluminum was more
than 25,000X below its Comparison Value
• Highest chromium reading was close to
its Comparison Value but was likely even
lower
• Highest manganese
reading was about
2-1/2X less than its Comparison Value
Metals - Conclusion:
• Exposure is occurring (metals are
present)
• Source cannot be determined (may be
multiple sources, including naturally
occurring)
• Concentrations do not exceed
Comparison Values
• No adverse health effects are expected
Air intake for
monitors inside
trailer
Mercury
• Monitored continuously, reporting a 5-
minute average
• Test measures elemental mercury vapor
• Average concentration well below
Comparison Values
• Some spikes, but still less than short-term
Comparison Values
Mercury – Conclusion:
• Exposure is occurring but no adverse
health effects are expected
• Has been referred to MDEQ (local
average concentration was greater than
background concentrations seen
elsewhere in Michigan, indicating a
source); MDEQ is planning more studies
in 2005
• Source cannot be determined from EI
data
“key”
Real-time
readout
Air inlet
ChemCassette
(treated paper tape)
Take-up
spool
Acid Monitor
Acidic Aerosols
• Monitored continuously
• More qualitative (was it there) rather
than quantitative (how much was there)
test
• Cannot verify if acid was HCl; it was
likely not HF
• No odors reported during time periods
when acids detected
Acidic Aerosols – Conclusion:
• Exposure is occurring but sporadically
• If the detected acid was HCl, the highest
concentration detected was still less than
the lowest short-term Comparison Value
and no adverse health effects would be
expected
• Source cannot be determined from EI
data
Summa canister
Open valve here
Air enters canister here
VOC Sampling
Locations
Control Samples
Odor Samples
Continental
Aluminum
Monitoring
trailer at Dolsen
VOCs
• Instantaneous (“grab”) sample taken by
local responder during odor event
• Each sample paired with a corresponding
“control” sample
• Four field blanks (unopened) also
analyzed
VOCs (cont’d)
• Field blanks had some detections
(expected)
• Control concentrations were sometimes
higher than odor-event concentrations
• Generally, all concentrations were well
below lowest Comparison Values
– Benzene was about ½ its Comparison Value
– 1,3-Butadiene was about 1/6 its Comparison
Value
VOCs – Conclusion:
• Exposure is occurring (VOCs are
common chemicals)
• No adverse health effects are expected
• Source cannot be determined from EI
data
Past exposure?
• No models exist for back-calculating an
air concentration from soil data
• Any attempt to estimate historic air
concentrations would be rife in
uncertainty
• Past public health hazard cannot be
determined
Exposure to soil?
• 2001 soil data from two residences
downwind of Continental Aluminum
– Measured many of the metals included in the
EI
– Most concentrations were below expected
background
– All concentrations well below Comparison
Values for soil (addressing skin contact and
accidental ingestion)
• Not expected to cause adverse health
effects
No Apparent Public Health
Hazard
• Category used for sites where human exposure
to contaminated media may be occurring, may
have occurred in the past, and/or may occur in
the future, but the exposure is not expected to
cause any adverse health effects.
• Based on critical data that ATSDR considers
sufficient to support a decision. Does not
necessarily imply that the available data are
complete, just that they are sufficient.
Blood Aluminum Levels
• MDCH was contacted by a parent who
had chosen to have her children’s blood
tested for aluminum levels and by the
clinic that tested the children
• The lab that did the analysis reported
aluminum levels greater than the lab’s
reference range
• What does this mean?
MDCH conferred with:
• The lead author of the Toxicological
Profile for Aluminum (ATSDR Division
of Toxicology)
• ATSDR Regional Office (Chicago)
• Pediatric Environmental Health
Specialty Unit (Chicago’s Cook County
Hospital)
• Michigan Poison Control Center (Detroit
Medical Center)
Aluminum Sources
• 3
rd
most common element (most common
metal) in earth’s crust
• Found in processed foods, acidic foods
cooked in aluminum pans, drinking
water, hygiene and medical products,
dust (from soil or smelting emissions)
• Exposure is inevitable due to abundance
and use
What follows exposure?
• Most ingested aluminum passes right
through the body, excreted in the feces
• Remainder absorbed, then excreted by
kidneys (some fruit juices enhance
absorption)
• Some inhaled aluminum may be retained
by lung, absorbed into body, then
excreted by kidneys
Should I get tested?
• Unless you have a kidney disorder that
requires dialysis, testing is not
recommended
• People with kidney disorders are unable
to excrete compounds efficiently and are
susceptible to toxic effects of many
chemicals
If you get tested anyway:
• Blood tests are preferred over urine tests
• Do not
use hair testing
• Know potential exposures ahead of time
(food, water, medicines, etc.) and
eliminate or minimize them
• Understand what “reference range” can
mean (next slide)
Reference Range
≠
Normal Range
No “normal range” has been
established for aluminum in blood.
If results are higher than the
reference range:
• Evaluate all recent potential exposures
with your doctor
• Re-test to verify results after doctor
reviews test method
• If necessary, assess kidney function
Bottom Line:
The environmental data do not indicate
excess aluminum (or any other tested
chemicals) in the area.
If your kidneys are in good health,
aluminum exposure (through everyday
activities or through exposure to
emissions from Continental Aluminum)
should not
negatively affect your health.
