chlorine bleaching

Chlorine bleaching of kraft wood pulp is another source.

Chlorine bleaching is believed responsible for the emission of toxic materials, including dioxin, from paper mills.

Chlorine bleaching of pulp for paper releases dioxins into rivers and soil, further polluting the environment.

Some of these are naturally occurring in the wood, but chlorine bleaching of the pulp produces far larger amounts.

Chlorine bleaching causes a number of pollution problems, primarily the formation of dioxins which can have serious health and environmental consequences.

• Dioxins and furans are undesirable compounds formed during the chlorine bleaching of chemical pulps.

Burning wastes, chlorine bleaching of pulp and paper, and some industrial processes can all create small quantities of dioxins.

Dioxins are produced by incineration, chemical processing, chlorine bleaching of paper and pulp, and the burning of diesel fuel.

Dioxin, a group of highly toxic chemicals are released during combustion processes, pesticide manufacturing and chlorine bleaching of wood pulp.

Chlorine bleaching of pulp and paper - historically important source of PCDD/Fs to waterways.

Also, oxygen delignification of sulphite pulp but not kraft pulp before chlorine bleaching increases the mutagenicity of the effluent (203,205 ).

The chemicals are byproducts of a number of industrial processes, like the chlorine bleaching of pulp done by Alaska Pulp in Sitka.

Elevated concentrations of these substances in some shellfish near some pulp and paper mills that use chlorine bleaching have necessitated closure of the affected fisheries in order to protect human health.

Chlorine bleaching of kraft wood pulp is another source of 2,3,7,8-TCDD, but this has not been identified as a major source of the compound in the Great Lakes aquatic ecosystem.

However, dioxins can result from natural processes including volcanic eruptions and forest fires, and manufacturing processes such as smelting, chlorine bleaching of paper pulp, and the creation of some herbicides and pesticides.

The PCDD/Fs are by-products of synthesis of many chlorinated organic chemicals, e.g., chlorophenols, and in chlorine bleaching of wood pulp, however, these sources have been greatly reduced during the 1990s.

Dioxins occur as by-products in the manufacture of some organochlorides, in the incineration of chlorine-containing substances such as polyvinyl chloride (PVC), in the chlorine bleaching of paper, and from natural sources such as volcanoes and forest fires.