Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!cbatt!cbosgd!ihnp4!ihlpg!tan From: tan@ihlpg.UUCP (Bill Tanenbaum) Newsgroups: net.politics,net.sci Subject: Re: life of nuclear wastes Message-ID: <2201@ihlpg.UUCP> Date: Tue, 15-Jul-86 15:12:27 EDT Article-I.D.: ihlpg.2201 Posted: Tue Jul 15 15:12:27 1986 Date-Received: Wed, 16-Jul-86 06:51:53 EDT References: <333@argus.UUCP> <523@gargoyle.UUCP> Organization: AT&T Bell Laboratories Lines: 33 Xref: watmath net.politics:17382 net.sci:1261 > [Kenneth Ng] > >When inhaled, plutonium is more dangerous: 1300 milligrams to cause > >cancer. ----- > [Richard Carnes] > The figure I have read in various places is that < 1 *microgram* of > Pu is sufficient to cause cancer if inhaled. It is less toxic if it > is not lodged in lungs or absorbed into bloodstream. Something is > amiss if published estimates differ by 6 or 7 orders of magnitude. ----- I suspect we have an apples and oranges comparison. In principle, 1 ATOM of a radioactive substance is sufficient to cause cancer, albeit with a low probability. Such statistics as that are meaningless for comparison. Some standard is needed, such as the amount of a substance inhaled that gives the inhalee a 50% chance of developing cancer within five years, or some such standard. Without this, pro and anti nuclear authors will use wildly divergent figures to back up their own biases. In any event, as an alpha-emitter, plutonium is pretty ordinary, when compared to other alpha emitters with a comparable half-life. Anyone who claims that the radioactivity from Pu in the lungs is much more likely to cause cancer than all or almost all other radioactive substances is misinformed. However, some radioactive substances are more dangerous because of their chemical resemblances to essential body chemicals. Obvious examples are Strontium 90 collecting in bones (resembles calcium) and Iodine 131 in the thyroid (resembles non-radioactive iodine). I don't know where, if anywhere, plutonium in the body tends to collect. The chemical toxicity of plutonium is, of course, a completely different matter. It is also conceivable that plutonium could be highly carcinogenic as a CHEMICAL, independent of its radioactivity. I don't know if this is true, either. -- Bill Tanenbaum - AT&T Bell Labs - Naperville IL ihnp4!ihlpg!tan