L1 /
3
CH3041
DIOXINs I
Related to PCDFs are the
75 Dioxin congeners
of which
2,3,7,8-TetraChloroDibenzoDioxin (TCDD)
is the most toxic and has a Toxic Equivalent
Factor TEF of 1.0. PeCDF = 0.5
2,3,7,8-TetraChloroDibenzoDioxin (TCDD)
is the most toxic and has a Toxic Equivalent
Factor TEF of 1.0. PeCDF = 0.5
• The Toxic Equivalent is the sum of all the
TEFs emitted eg. 0.75g TCDD + 2g PeCDF
TEQ = (0.75 x 1) + (2 x 0.5) = 1.75g TEQ / t soil
TEFs emitted eg. 0.75g TCDD + 2g PeCDF
TEQ = (0.75 x 1) + (2 x 0.5) = 1.75g TEQ / t soil
• TCDD is carcinogenic and teratogenic,
causes liver malfunction, skeletal problems..
causes liver malfunction, skeletal problems..
• TCDD is formed in Cl2 bleaching of pulp
which is why this has
been phased out.
• The Dioxins and PCDFs are hydrophobic
and lipophilic and sorb to sediments.
and lipophilic and sorb to sediments.
