Re: Dioxin standards for compost ?

[Ferdinand.Engelbeen@ping.be (Ferdinand Engelbeen)]

Philip Fleisher asked for dioxin standards in compost.

We are not aware of standards or guidelines for dioxin in compost, but it
is not very important, because normally the dioxin from compost is not
assimilated by plants.

The average level of dioxin found in biocompost is 14 pg/g (Hagenmaier,
1992) and in sludge from municipal waste water treatment, also used in
agriculture, the average is 62 ng/g.

The amount of dioxin accumulating via worms to birds will not be high,
compared with the more important accumulation route via cows directly
eating contaminated dust (in general from incinerators) on grass to cow
milk - diary products - human fat/milk - babies.

>MacMillan Bloedel Powell River Division has a permit application
>before the BC Ministry of Environment to allow them to run some
>field trials on some alternative disposal methods for pulp mill
>wastes.  The wastes include grate ash and primary and secondary
>sludge.
>
>(The mill is an ECF convert though not 100% converted at this
>point.)
>
>Primary sludge is 96% water and has a dioxin TEQ in the 50 to 700
>pg/g range (min and max from the sequence of months for which
>measurements are available.)
>
>They propose to make compost and spread it around here in the field
>trial and, if this works, go into 'production'.
>
>They will add mineral nitrogen to the sludge.  The sludge contains
>contaminants other than dioxin.  The metals have been measured and
>they appear to be within standards for metal content for compost.
>No other compost standards are mentioned.
>
>Does anyone know of any standards or guidelines for dioxin in
>compost?
>
>
>Philip Fleischer
>philip@prcn.org