Dioxin formation in pulp and paper mills of India

Abstract

Samples of effluents, sludge, pulp, final products (paper) and soil were collected from the identified pulp and paper mills in India. The samples were analysed for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and other dioxin congeners and precursors. Pulp and paper mills using chlorine for the bleaching process showed the presence of 2,3,7,8-TCDD in effluent samples. In the effluent and pulp samples from mills where chlorine dioxide was used as a bleaching agent, the 2,3,7,8-TCDD congener ranged from below the detection limit 0.05 to 0.12 ngL(-1)/ngg(-1). The relative standard deviation of reproducibility and the percent recovery of 2,3,7,8-TCDD were 2.07 and 82.4% in pulp and 2.8 and 92% in effluent, respectively. The 1,3,6,8-TCDD was the only other major dioxin congener found in the treated and untreated effluent and sludge samples. However, dichlorobenzene, trichlorophenyl, and hexachlorobiphenyl were detected in all samples. The formation of dioxins can be minimised by replacing chlorine with chlorine dioxide in bleaching processes in pulp and paper mills.

Dioxin- and POP-contaminated sites—contemporary and future relevance and challenges

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Waste paper for recycling: Overview and identification of potentially critical substances

“…Another study showed waste paper as the main source of dioxins and furans 410 in a paper recycling facility (Santl et al, 1994). The issue is especially relevant for emerging 411 economies, where potentially more lenient environmental legislations are applied and elemental 412 chlorine may still be in use, thus resulting in detectable levels of dioxins and furans in pulp, paper 413 and effluents (Thacker et al, 2007;Zheng et al, 2001). 414…”

Isolation and characterization of alkalotolerant Pseudomonas sp. strain ISTDF1 for degradation of dibenzofuran

“…The pulp and paper industry is known as one of the important polluting sources for one of the most recalcitrant compounds-dioxin [4,32]. Only a few bacteria have been reported so far that can grow directly on chlorinated dioxins such as Sphingomonas sp.…”