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PCBs What’s this ?

PCBs What’s this ?. But really …. They are more or less viscous or resinous liquids, insoluble in water, colourless or yellowish. They only break down at temperatures exceeding 1000 ° C. They can dissolve or soften some rubbers and plastics.

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PCBs What’s this ?

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  1. PCBs What’s this ?

  2. But really …

  3. They are more or less viscous or resinous liquids, insoluble in water, colourless or yellowish. They only break down at temperatures exceeding 1000 ° C. They can dissolve or soften some rubbers and plastics. These persistent pollutants (half-life of 94 days to 2 700 years depending on the molecules) have a high toxicity. They are found in some fatty tissues in humans, including human milk. Blood test is generally used to detect contamination.

  4. P……,C……,B…… poly = several chloro = chlorine atoms bi = two phenyl = group of atoms of carbon and hydrogen biphenyl = C12H10 polychlorobiphenyl = C12H(10-x-y)Cl(x+y)

  5. Example PCB 2,3,5’,6’- tetrachlorobiphenyl is represented by the formula : C12H6Cl4

  6. A living molecule …

  7. What are the dangers to humans and the environment? PCBs are toxic, subject to bioaccumulation, they persist in the environment due to their slow biodegradability. They are strongly suspected of being carcinogenic, without this having been proved.

  8. The safety standards of PCBs The protection of health is the main axis of these standards. These contaminants are hazardous to health. Food is the major route of exposure to contaminants. The dioxin-like PCBs are both highly toxic and carcinogenic.

  9. The new standards • The new standards which were adopted constitute a major advance in the protection of health as they set new maximum levels. • So from now on the countries affected by the presence of dioxin-like PCBs may take measures to protect consumers.

  10. The standards in figures Accepted standard of PCB content in fish : 8 pg / g Accepted standard of PCB content in food : 70 picograms / kg / month

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