This is a public-interest archive. Personal data is pseudonymized and retained under GDPR Article 89.

Re: Contaminated bone meal

Square Foot Gardening List - http://www.flinet.com/~gallus/sqft.html

At 10:24 PM 5/16/99 EDT, Lisa Viger wrote:

>     The above is the same for people. The "infectious" agent (actually a 
>prion, which is a piece of protein which has not been decided if it meets the 
>crtiteria of being alive or not) isn't exactly "infectious." It's caused by 
>eating meat from an animal which has eaten what is described above. The prion 
>which causes BSE cannot reproduce, so the effects are cumulative. IOW, you 
>may ingest, say, 100 BSE prions in your burger tomorrow (if that cow had also 
>ingested the BSE prions). It may not cause any problems. If you ate that same 
>number every day, eventually you'd have enough of the prions to literally 
>bounce around in your brain making a significant number of holes (hence, the 
>"spongiform" part.....the brains of infected animals and people have holes in 
>them like are in a sponge). And Janet, correct me please if I'm wrong in my 
>understanding of BSE.

Can't say as I've ever heard it explained like this.

If we accept the hypothesis that scrapie in sheep (a *very* old disease, in
the UK for more than 250 years) becomes BSE in cattle when the cattle eat
protein-enhanced foods made from scrapie-killed sheep, then we must accept
the notion that prions can be KILLED.

Here's why:

Scrapie has been around basically forever in the British Isles, and
protein-enhanced cattle feed has been around for decades (plural), some of
it made from scrapied sheep.  But before the mid 1980's, rendering processes
in Britain combined heat and chemical solvents (not unlike those used at the
dry cleaners' and equally dangerous for people to be around).  During that
period, British cattle were not coming down with BSE.

But then the rendering rules changed to eliminate the "solvent extraction
method" and get rid of those nasty petrochemical solvents, to protect
rendering plant workers.

Shortly after that, cows in the UK began to get BSE.

It would appear, then, that the combination of heat plus solvent was
sufficient to KILL the scrapie/BSE-causing prions but heat alone (the
current regime) is not enough.

It seems to me that if prions can be killed, they must perforce be alive.
However, if it's true that they cannot reproduce (first time I've heard that
part), certainly they are operating under a different understanding of the
word "alive" than you and I are.

The idea of them pinging around inside brain tissue, making holes, sounds
bizarre.

It might be useful to find out if the New Guinea women who died of kuru
after consuming the brains of their dead (and spongiform-infected) relatives
got sick after just one of these ritual meals or required many such
exposures to the kuru agent (per Lisa's suggested profile).

>     Lovely, something else to worry about! As far as deciding whether or not 
>to use bonemeal in the US, I think the fact the FDA has quietly taken gelatin 
>(made from bones and connective tissue leftovers) off their "Generally 
>Regarded as Safe" list, says quite a bit.

Speaks volumes to me!

>     I wish I was as eloquent as Janet! But, I won't be using bone or blood 
>meal in my garden.

Thanks, Lisa.  You may be newer to the list than my last set of posts about
BSE (prolly 6-8 months ago).  I'm a writer/editor in the Legislative &
Public Affairs shop at USDA-APHIS.

In fact, this will have to be my last on the subject for a bit.  I'm headed
to Minneapolis Monday morning on business.  Back onlist Friday night.

--Janet


______________________________________________________________________
To unsubscribe, write to sqft-unsubscribe@listbot.com
Start Your Own FREE Email List at http://www.listbot.com/
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index