Thacker Neeta P, Nitnaware Vaishali C, Das Swapnesh K, Devotta Sukumar
National Environmental Engineering Research Institute, Nehru Marg, Nagpur- 440 020, India.
Environ Sci Pollut Res Int. 2007 Jun;14(4):225-6. doi: 10.1065/espr2007.02.386.
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.
从印度已确定的制浆造纸厂采集了废水、污泥、纸浆、最终产品(纸张)和土壤样本。对样本进行了2,3,7,8-四氯二苯并对二恶英(2,3,7,8-TCDD)以及其他二恶英同系物和前体的分析。在漂白过程中使用氯气的制浆造纸厂,其废水样本中检测到了2,3,7,8-TCDD。在使用二氧化氯作为漂白剂的工厂的废水和纸浆样本中,2,3,7,8-TCDD同系物的含量范围为低于检测限0.05至0.12纳克/升/纳克/克。纸浆中2,3,7,8-TCDD的重复性相对标准偏差和回收率分别为2.07和82.4%,废水中分别为2.8和92%。1,3,6,8-TCDD是在经过处理和未处理的废水及污泥样本中发现的唯一其他主要二恶英同系物。然而,在所有样本中均检测到了二氯苯、三氯苯基和六氯联苯。通过在制浆造纸厂的漂白过程中用二氧化氯替代氯气,可以将二恶英的形成降至最低。