Xref: utzoo can.general:1004 sci.bio:1595 sci.med:7771 sci.misc:2816
Path: utzoo!mnetor!micomvax!ncc!apss!nmm
From: nmm@apss.ab.ca (Neil McCulloch)
Newsgroups: can.general,sci.bio,sci.med,sci.misc
Subject: Re: Dioxin and Native Communities
Summary: quadrillion?
Message-ID: <591@apss.apss.ab.ca>
Date: 14 Nov 88 11:30:22 GMT
References: <544@yunccn.UUCP>
Organization: Alberta Public Safety Services
Lines: 15

In article <544@yunccn.UUCP>, john@yunccn.UUCP (John Hummel) writes:
> Keywords: Dioxin Pollution Health
> 1)"Tests have revealed 210 parts per trillion of 2,3,7,8-TCDD, the most
> 
> 1 to 9 parts per trillion." (MOE Press Release July 17,1986)
> 
> ces.No 2,3,7,8-TCDD was found at a detection level of 20 parts per quadrillion

Would someone with experience of testing for trace chemicals care to 
comment on these levels? 20 parts per quadrillion! Now that's 20 parts in
1,000,000,000,000,000. I find it hard to believe that reliable measurements
can be made at this level from samples taken in the field.

thanks,
neil