Mass balance modeling to elucidate historical and continuing sources of dioxin into an urban estuary

Longitudinal estimates of sediment-water diffusive flux of PCB congeners in the Houston Ship Channel

“…Highly contaminated sediment gets buried via sedimentation, but in this case the sedimentation that is occurring contains PCBs that are still present at relatively high levels. The original source of these sediments is not entirely clear as much of it in the highly industrialized upper portion of the HSC may simply be the same sediment being flushed back and forth with the tide which merely redistributes the surficial sediment PCBs rather than burying them (some evidence supporting this finding is presented in Rifai et al (2013) for PCDD/F contamination in the HSC). Another possibility is that PCBimpacted suspended sediment from further upstream causes the net sedimentation, and such a scenario might be restorative for the HSC as long as most of the suspended sediment was at lower chemical activity than the surficial sediment on which it deposits.…”

Occurrence and distribution of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in industrial and domestic sewage sludge

“…The HSC is associated with pulp and paper mills, shipping, and petrochemical refineries, along with other industrial activities that have been identified as potential sources of PCDD/Fs and other organic contaminants. Previous studies focused on the HSC (Correa et al 2006, Correa et al 2004, Dean et al 2009, Howell et al 2011, Raun et al 2005, Rifai et al 2013, Suarez et al 2006a, Suarez et al 2006b, Yeager et al 2007 have all reported the widespread presence of dioxin in its water, sediment, tissue, and air.…”

An Environmental Risk Evaluation Method Employing Atmospheric Dispersion Models and GIS

“…[16][17][18][19][20] modeled the behavior of dioxins in the atmosphere. Further, [21,22] used dispersion models to conduct simulations of the behavior of dioxins in bodies of water such as sea waters and canals, and [23] modeled the behavior of dioxins in bodies of water. [7,8] in the above-mentioned related research conducted a comparison of estimated dioxin levels, which were the results of simulation of behavior of dioxins conducted using ADMER, an atmospheric dispersion model, and actual measured levels of dioxins in the environment.…”

“…Source data is source location (longitude and latitude), annual emissions and emissions elevation; chemical substance parameters are the molecular weight and form of the chemical substance. Concerning the dioxin parameters, referring to the related research previously mentioned [1,4,5,[7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] and the Ministry of the Environment (2004) [3], the molecular weight of a dioxin was assumed to be 388, the molecular weight for PeCDF, which occurs in the greatest percentage at incineration plant exhaust gas dioxin levels, and the form of a dioxin was entered into METI-LIS as a particulate spherical shape.…”