RE: Dioxin Queries

["Igning S. Braga" <igning.braga@jollibee.com.ph>]

I'm resending this mail. (apologies). Can anyone please respond ? currently 
i'm finalizing my seminar paper which i'll be conducting next week.  thank 
you .

It will help me greatly if anyone can answer or clarify the following:

1. P450 detox system cannot suppress or remove dioxin toxicity. Is this
true ?

2.  What is P450  made of ?

3. Does anyone know USFDA/USDA standards on dioxin level of food products.
i.e. acceptable dioxin level in chickem is ____/grams. I've seen these
article regarding incident last July 1997 wherein USDA banned some chicken
and eggs over dioxin contamination because they contained more than 1 part
per trillion of dioxin. So, they must have some basis on their directive.
If USDA are able to impose such action then they must have standard on
maximum dioxin level acceptable for each particular food product. Does
anybody have a copy of the standard? Does anybody know food standards on
dioxin level, like maximum acceptable level ?

Most of the articles regarding dioxin includes EPA, WHO, ASTDR minimum risk 
level or safe dose level but i wasn't able to  see an article which
includes USFDA/USDA standards.

4. Can anyone please check the following information :

	EPA - safe dose level is 0.006 pg TCDD/kg of body weight/day
	ASTDR - minimum risk level is 1 pg TCDD/kg of body weight/day
	WHO - safety threshold : 10 pg/kg of body weight/day
		* WHO standard on safety threshold is referring to TCDD

5. Dioxin get into people and wildlife primarily thru food. Articles
mentioned about dioxin generated from incinerators and travel through air
and fall out in our farmlands which in turn gets into cows and contaminate
milk and meat. But there was no mention of aerial inhalation considered as
a potential pathways of human exposure to dioxin. Does anyone know if
aerial inhalation results to dioxin toxicity? if yes, is the amount of
dioxin significant that we should be alarmed ?

6. Based on EPA's Theories of Dioxin Formation During Combustion, the feed
material to the combustor containing CDDs and CDFs and some portion
survives thermal stress imposed by the heat of the incinerator combustion
process and is subsequently emitted from the stack. Does this mean that
there are no other thermal treatment which can be used in incineration
process which can prevent dioxin formation ? In the same way it can be said 
that dioxin contaminated product should be disposed properly, that it
cannot be simply burned ?

7. Does anyone know the proper way of disposal of dioxin contaminated food
products ? Like how did Belgium disposed of all the dioxin contaminated
food items banned for release ?

8. It was also written that the only environmentally significant
transformation process for this congeners is believed to be
photodegradation (removal of CDDs and CDFs). Can anybody please give me
information on photodegradation process ?

Your informations, inputs and comments are appreciated.
Thank you.