Asbestos concerns in the 21st century:

The Libby, Montana issue

Mickey GunterUniversity of Idaho

Moscow, Idaho

plus, other thoughts

Talk overview

• Libby overview

• Critical thought(s)

• Basic (?) knowledge

• Teaching idea, approach & information

• Good mineral, bad mineral

• What’s the “real” environmental concern(s)

Libby overview

Am Min (1959)

Libby mining details

• 1923: Start of operations• 1950’s: 1,200,000 tons / year, ~30% vermiculite & 5%

“tremolite” with 1/2 of that being asbestos• 1964: WR Grace buys mine• 1980’s: Medical studies• 1990: Mine closes• 1999: PI & EPA, ATSDR, etc….

Seattle Post

Death statistics (U.S.A./year)

- 2,100,000: deaths

- 600,000: heart diseases

- 500,000: cancer

- 150,000: lung cancer

- 435,000: smoking cigs

- 400,000: (too much) food

- 85,000: (too much) booze

- 43,000: auto accidents

“The dose makes the poison” (Paracelsus, 1567).

290,000,000

Death statistics (asbestos and…)

- asbestosis ~ 300

- silicosis ~ 100

- mesothelioma ~ 300

- airlines & lightning ~ 150

- mad cow disease ~ 0

- snake bites ~ 0

- SARs & countless others < 10

Risk of death vs Fear of death

risk of death

fear ofdeath

- self imposed

- by ignorance

Teaching idea

Teaching approach

• overview of “problem”• define material, properties & analytical stuff• describe diseases & exposures• discuss case studies• discuss risk & societal impact(s) in context• What’s the “real problem”?

Obtaining (accurate) information

Now what?

• Refereed literature• Common sense

– 35,000,000 homes with Zonolite in USA

• Non-biased sources– Whose side are you on?– Where does funding come from, for either side?

• “Correct” government sources– Vital statistics of the USA– Agencies working in “their” area of specialty

0

100

200

300

400

1970 1980 1990

year

deaths

asbestosis

silicosis

Silicosis & asbestosis deaths in the U.S.A.

Gunter 1999

60,000

85,000

110,000

135,000

160,000

1970 1980 1990

year

lung cancer deaths

Lung cancer deaths in the U.S.A.

Libby diseases & on-going issues

• Libby miner studies (1986 & 2003), SMR’s– ~ 250 for asbestosis, mesothelioma & lung cancer

• Local lawsuits• Mr. Crayon, EPA, ATSDR & residents

– 11 asbestosis deaths, no mesothelioma– no elevated lung cancer rate

• MEG lung cancer SMR = 137 (10) & 133 (5) • Tremolite at Libby?• Zonolite in 35,000,000 homes nationwide

Zonolite insulation & respirable asbestos

bag weight = 6,000 grams < 177 m = 65 grams

Background levels of dust

In air: - 0.0004 to 0.01 fibers / cc -> breathe 4,000 to 100,000 fibers / day

(Mossman et al. 1990, Klein 1993)

- 10g / m3 (of 5m sized particles) -> breathe 2,500,000 particles / day(Norton & Gunter 1999)

In lungs: - 80,000,000 “fibers” with 50% asbestos

general population Vancouver, BC (Chrug 1983)

- white-asbestos = 50,000,000 and tremolite-asbestos = 6,000,000general population San Francisco (Chrug & Warnock 1980)

Good mineral, bad mineral?

“Since the benefits of the natural environment in providing essential elements and nutrients are well known, the focus in this book has been on the harmful side of the relationship.” From Geology and Health, Skinner & Berger

25% of world

population at r

isk

Asbestos: good mineral, bad mineral?

Overview of real “superfund” site(s)

Final thoughts

• As scientists, we must be skeptical enough to question anything, while being open-minded enough to consider everything.

• And ……quartz……rant

• And….…worry….…rave