快猫短视频

IT WILL take 25 years to banish PCBs (polychlorinated biphenyls), one of the
planet鈥檚 most widespread industrial poisons, delegates at a UN conference have
decided.

This week, in a decision applauded by environmentalists, 122 nations in
Johannesburg agreed a landmark treaty that will eventually ban 12 of the world鈥檚
most toxic chemicals, known as persistent organic pollutants (POPs). These
pesticides and industrial chemicals accumulate in the environment and have been
linked to reproductive and nervous system damage in animals and people.

The deal will become a legally binding treaty once it has been signed by 50
countries, which should take four or five years. It also puts in place a system
for tracking down other POPs currently in use, and for preventing industry from
manufacturing more.

But the conference concluded that it will not be able to eliminate PCBs until
2025鈥攁lmost 50 years after their manufacture was ended across most of the
world.

PCBs have been widely used as an insulating liquid inside electrical
transformers. Hundreds of thousands of tonnes are still scattered across the
globe in deteriorating electrical equipment and waste drums. The conference
warned that nations should stop leaks from equipment and ensure safe disposal of
waste PCBs. But the clean-up job will be hard to achieve and could take years,
the delegates agreed.

Russia has the largest stocks. The head of the Russian delegation at the
conference, Valentine Sokolovskyi, says: 鈥淧CBs are our biggest problem. We have
something like 35 000 tonnes in our transformers.鈥� 快猫短视频s say leaks from
this equipment are largely responsible for the build-up of PCBs in the Arctic,
where high levels have been found in reindeer and marine mammals.