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Associated topic: persistent organic pollutants

Emissions monitoring period: since 1990

Data source: CITEPA / SECTEN format - April 2017


Source of the pollutant

Dioxins (PCDD-F) are a group of polychlorobenzodioxins (PCDDs) and polychlorodibenzofurans (PCDFs). PCDDs comprise 75 congeners (1) and PCDFs comprise 135 congeners.

PCDD-F are expressed in "International Toxic Equivalents" or I-TEQ(2).

Dioxin emissions can be from natural or industrial sources. Dioxins are emitted naturally by events such as forest fires and, to a lesser extent, volcanic eruptions. The complex phenomena causing the formation of dioxins and furans occur under particular conditions of combustion that are found in all sectors but more particularly during waste incineration and mineral agglomeration in the iron and steel industry, and in a number of other specific processes.

 (1) Congeners : in carbons containing a single atom of hydrogen, this is sometimes replaced by a halogen atom (usually chloride or bromide), forming a compound with the same ring structure but a different hydrogen number.

(2) I-TEQ : the "toxic equivalency" system (TEQ) expresses the relative toxicity of each less toxic compound as a fraction of the toxicity of the most toxic TCDD. A "Toxic Equivalency Factor" (TEF) is assigned to each compound. This weighting coefficient indicates the degree of toxicity compared to 2,3,7,8-TCDD, which has the reference value 1. To calculate the overall toxic equivalency of a combination of dioxins compared to TCDD, the quantities of each toxic compound are multiplied by their respective Toxic Equivalency Factors (TEF), which are then added together


Effect of the pollutant

Dioxins are very stable chemically, do not easily biodegrade and persist in the environment and the living organisms in which they accumulate. These pollutants have a half-life of about seven years in the human body. The chronic toxicity of dioxins has been intensively researched in the last few years. Their toxicity to humans at chronic low doses is still disputed, as studies on the subject are not easy to conduct. However, several epidemiological studies (in humans) have reported an increase in cancer cases among people exposed to the most toxic dioxin, 2,3,7,8 TCCD (the "Seveso dioxin"), which is the only dioxin classified by the International Agency for Research on Cancer (IARC) as "carcinogenic to humans".


Classification of sub-sectors* with the highest emission levels in 2015

Classification Sub-sectors Share of sub-sector in total national emissions in mainland France
1 Residential sector including: 45% including:
Wire burning 35%
Combustion of heating appliances (boilers, inserts, closed and open fireplaces, stoves, etc.) 10%
2 Ferrous metals production 16%
3 Diesel-fuelled passenger cars 12%
4 Solid mineral fuel conversion - iron and steel 7.9%
5 Crops 4.7%

*: one sector out of six (energy transformation, manufacturing industry, residential/tertiary, agriculture/forestry, road transport and other transport) is broken down into sub-sectors.


Emissions and trends

Minimum observed: 114 g ITEQ in 2015
Maximum observed: 1 921 g ITEQ in 1994
Emissions in 2015: 114 g ITEQ
Trends 2015/1990: -93.6%
Trends 2015/maximum: -94.1%
Trends 2015/minimum: 0%

Measurement unit: g ITEQ (gram International Toxic Equivalent)
Source CITEPA / SECTEN format – April 2017

 Graph PCDD F 17

Graph Legende sans UTCFv2

Source CITEPA / SECTEN format – April 2017

Tab PCDD F 17(*) Following UNECE/NEC definitions : emissions classified "except total" are not included, i.e. emissions from international maritime, emissions from domestic and international air transport cruise (≥ 1000 m), emissions from agriculture and forestry biogenic sources and emissions from non-anthropogenic sources.
(e) preliminary estimate



Emissions of dioxins and furans (PCDD-F) are expressed in I-TEQ (international toxic equivalency).

The complex conditions required enabling the formation of dioxins and furans are... (to read more, consult the SECTEN report online via your login and password)

Data source: CITEPA / SECTEN format - April 2017