DIOXIN AND PAH EMISSIONS COMPARED
A lot of research is done on dioxin emissions in near all Western countries. PAH emissions are more seldom investigated. Very rare are simultaneous measurements from the same sources for PAH's and dioxins. Here follows the first comprehensive investigation of PAH and dioxin emissions of many sources in Flanders (Northern Belgium) :
The total emission of dioxins/furans is 274 gram I-TEQ per year from most known sources. The total emission of PAH's is 284 tonnes (!) per year. If we use an estimate of 1% BaP (benzo-a-pyrene) in the PAH's, then the total yearly emission of BaP surpasses the amount of I-TEQ dioxins with a factor 10,000
Based on the cancer risk for rats, BaP is app. 20 times less carcinogenic than TCDD-dioxin. For cancer initiating/promoting activity, the amounts of BaP emitted are still a factor 500 more relevant for cancer risk than dioxins. For other health effects (based on the Ah-receptor affinity) that is a factor 2,000.
The most relevant sources of dioxins and PAH's in descending order for dioxins with relative health effects, with some addition from other sources in the literature:
|Health comparison of PCDD/F and PAH emissions|
|Process:||PCDD/F g I-TEQ/yr||PAH's ton/yr||BaP kg/yr||Cancer risk BaP:TEQ||toxicity BaP:TEQ||Source|
|Iron and steel production:||118.000||1.859||18.59||8||32|||
|Incineration of household waste:||9.170||0.029||0.29||2||6|||
|Backyard barrel burning (per 1000 ton):||0.790||0.045||0.45||28||114|||
|Dieselmotor of three ships:||0.108||0.033||0.33||154||615|||
|Soot of Düsseldorf airport fire (per ton):||0.052||4.986||0.26||255||1019|||
|Wood smoke composition (per 1000 ton):||25.000||0.050||2.65||5||21|||
While there is a large variation in ratio between dioxins and PAH's, the latter in all cases are emitted in (far) higher amounts as well as in higher toxicological relevance. The lowest ratio seems to be incineration of household waste, where the BaP to TEQ ratio is only 30:1, still 1.5 times higher in cancer "rate" and 6 times higher in toxicology "rate". This is probably the result of process conditions and stack gas treatment, as the same waste in backyard barrel burning had a measured BaP to dioxin ration of 400:1 to 16,000:1.
Even if PVC would be responsable for all dioxin emissions in hospital waste incineration, that is completely surpassed by the 200 fold higher dioxin emissions of the iron/steel industry, mainly from iron ore sintering, based on entirely natural, uncontaminated raw materials.
All forms of incineration or heating, all processes using any form of fossil heating and any form of combustion in transport will give emissions of PAH's and dioxins, In every case much higher amounts of PAH's with higher relevancy for cancer risk and toxicity. And nothing can be produced and/or recycled and/or incinerated without the release of PAH's and dioxins.
Based on these figures, we expect that Greenpeace, and so many others who want a complete elimination of PVC and other chlorine products, will act for an immediate ban of (stainless) steel, household heating, seaships (including their own fleet)... And as PVC has only half the carbon content of other plastics, adopting the precautionary principle against the release of PAH's, we should exchange all the 100% hydrocarbon based alternatives by PVC...
You are at level two of the Chlorophiles pages.
Created: September 28, 1999.
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