A series of laboratory experiments were conducted to examine the leaching of decabromodiphenyl ether(BDE-209)and hexabromocyclododecane(HBCDD)from a mix of three fabrics.Consistent with previous reports that such leac...A series of laboratory experiments were conducted to examine the leaching of decabromodiphenyl ether(BDE-209)and hexabromocyclododecane(HBCDD)from a mix of three fabrics.Consistent with previous reports that such leaching is governed by second order kinetics,concentrations in leachate were markedly higher in the first 24 h of leaching,and diminished by an order of magnitude after 1 week.The influence of the waste:leachate ratio was examined for the first time,with leaching of both BDE-209 and HBCDD significantly greater(p<0.05)at a waste:leachate ratio of 0.005 g/mL than at 0.05 g/mL.Using dissolved humic matter(DHM)solutions as proxy for simulating organic landfill leachates we found that leaching of both BDE-209 and HBCDD was also significantly greater at a DHM concentration of 1,000 mg/L in leachate compared to that observed at DHM values of 100 and 0 mg/L.Agitation of waste:leachate mixtures significantly enhanced leaching.While leaching of HBCDD decreased significantly as leachate pH increased from 5.8,through 6.5,to 8.5;no significant impact of pH on leaching of BDE-209 was detected.Concentrations in leachate of both BDE-209 and HBCDD decreased significantly on increasing leachate temperature from 20℃to 60℃and 80℃.This is considered most likely due to volatilisation of these contaminants into the headspace of the leaching vessel at higher temperatures.展开更多
基金This project(FUEL,reference 2016-HW-MS-8)is funded under the EPA Research Programme 2014-2020The EPA Research Programme is a Government of Ireland initiative funded by the Department of Communications,Climate Action and Environment.
文摘A series of laboratory experiments were conducted to examine the leaching of decabromodiphenyl ether(BDE-209)and hexabromocyclododecane(HBCDD)from a mix of three fabrics.Consistent with previous reports that such leaching is governed by second order kinetics,concentrations in leachate were markedly higher in the first 24 h of leaching,and diminished by an order of magnitude after 1 week.The influence of the waste:leachate ratio was examined for the first time,with leaching of both BDE-209 and HBCDD significantly greater(p<0.05)at a waste:leachate ratio of 0.005 g/mL than at 0.05 g/mL.Using dissolved humic matter(DHM)solutions as proxy for simulating organic landfill leachates we found that leaching of both BDE-209 and HBCDD was also significantly greater at a DHM concentration of 1,000 mg/L in leachate compared to that observed at DHM values of 100 and 0 mg/L.Agitation of waste:leachate mixtures significantly enhanced leaching.While leaching of HBCDD decreased significantly as leachate pH increased from 5.8,through 6.5,to 8.5;no significant impact of pH on leaching of BDE-209 was detected.Concentrations in leachate of both BDE-209 and HBCDD decreased significantly on increasing leachate temperature from 20℃to 60℃and 80℃.This is considered most likely due to volatilisation of these contaminants into the headspace of the leaching vessel at higher temperatures.
