Sub Mystery Questions - 2/3/2011

BACKGROUND
Nuclear submariners live and work in an atmosphere composed of approximately 80% naturally occurring nitrogen, 19% oxygen (manufactured aboard ship), and a complex mixture of inorganic and organic contaminants. The concentrations of contaminants exist as a balance between the rates of production from human and operational activities and the rate of removal by engineering systems. The biological effects of inorganic gases, particularly carbon dioxide, have been extensively studied. Investigators are now attempting to define the composition and concentration of volatile organic compounds that accumulate during 90-day submergences. Medical studies have not conclusively shown that crewmembers incur adverse health effects from continuous exposures to the sealed atmospheres of nuclear submarines. - Submarine atmospheres, Naval Submarine Medical Research Laboratory, Groton, CT, 1989.
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Personal BACKGROUND
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During overhaul some of us can recall shipyard welders using small asbestos blankets to protect adjacent areas from heat, slag and fire hazards. This was commonplace both on the sub's hull and in its interior spaces. When blankets got too hot, visible black threads (up to 3 inches long) floated through the air. Respiration masks were not used at the time. Despite precautions and round-the-clock fire watches, fires happened at least weekly and were controlled by a bluejacket with a fully-charged fire extinguisher.
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I would see the same black threads floating through the air at station stops on New York commuter railroads in the 1980s. The accompanying brake odor was unmistakable. Rail transit car air brakes certainly contained asbestos in years leading to the 1989 atmosphere abstract (above). Regular commuters (including MDs, PhDs, Engineers, etc.) on station platforms were regularly exposed to the potential of inhaling asbestos after submarine crews were not.
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Naval Submarine Review
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In fact, the asbestos hazard instigated additional studies to further protect submariners. Another Naval Submarine Medical Research Laboratory literature review involved Fibrous Glass Aerosls - Bruce R. Laverty, 1987, (exactly what it sounds like). Dr. Laverty states in his introduction:

Historically, atmosphere sampling aboard nuclear submarines has shown cigarette smoke, lubricating oils, and cooling oils and fats to be the major contaminents. ... Considering that asbestos is no longer recommended for use, secondary to its carcinogenic and co-carcinogenic qualities, fibrous glass [h]as become a common substitute. One use of fibrous glass aboard the Ohio class submarine is acoustic and thermal insulation around perforated ducting, which runs many exposed, high traffic spaces, i.e. crew's berthing spaces.

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Tradeoffs are involved by necessity in determining the best practices applicable to almost every professional discipline (health, engineering, medicine, etc.). As knowledge has accumulated, related best practices have improved. Such determinations are obviously very important to humans, and some can be found at the EPA's HERO site.
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MYSTERY QUESTIONS of the WEEK (answers Tuesday):
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1) - Dr. Laverty's review cites animal, in vitro, and human studies. What breeds of animal were cited?
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2) - How many, if any, of these animals were "sacrificed" according to Dr. Laverty's review?
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3) - How many, if any, of these animals were "sacrificed" according to the study cited?
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4) - Besides asbestos, what other major contaminant has been eliminated since 1987?
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5) - BONUS (only a few readers are up to this): What was the good Dr. Laverty's medical specialty and what was his last known military rank?
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Submarines are always silent and strange.