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Researchers from Rutgers University, NJ, measured the adsorption of polycyclic aromatic hydrocarbons by soot carbon and aerosol organic matter using soot/air and octanol air partition coefficients as an evaluation tools.

Researchers from Rutgers University measured the concentration of polycyclic aromatic hydrocarbons such as phenanthrene and benzopyrene in the atmosphere of the New Jersey coast.

A report provides proof of dynamic air-water exchange of polychlorinated dibenzo-p-dioxins and furans in the Hudson River Estuary.

Researchers from Rutgers University, New Jersey evaluated the atmospheric seasonal trends of alkylphenols, nonylphenol and tert-octylphenol, in the atmosphere of the lower Hudson River Estuary region during the period of June to December of 1998.

Results of a study indicate that air-water exchange dynamics are influenced by phytoplankton biomass, physical parameters, and growth rate.

Researchers from Rutgers University, NJ, documented for the first the presence of nonylphenols in the atmosphere arising from the biodegradation of nonylphenol polyethoxylates, a popular household surfactant, in water. The byproduct is an estrogenic nonylphenol, evaporating from the estuarine waters to the coastal atmosphere and is found in high concentrations from New York to New Jersey.

The concentration of polychlorinated biphenyls (PCB) and polycylic aromatic hydrocarbons (PAH) in both snow and rain water samples were correlated with PCB and PAH readings in air samples to study atmospheric scavenging of both pollutants. PCB and PAH concentrations were shown to highest in the snow samples, which shows atmospheric scavenging to be dependent on the particle phase of the pollutant. Air scavenging of the pollutants were shown to be effective only on pollutants with low molecular weight.

Results from the gas-particle partitioning of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons in the urban Chicago and the adjacent southern Lake Michigan atmosphere reveal that the PAHs and PCBs in the areas are at equilibrium. The slopes of the regressions of log Kp against the subcooled liquid vapor pressure from samples continental background origin are among the smallest measured, -0.70 to -0.53 and -0.16 to -0.56 for PAHs and PCBs, respectively. The figures indicate sufficient atmospheric residence times to reach equilibrium.

Higher surface concentrations of the pesticide toxaphene was found in the northern part of Lake Michigan than in the southern part of the lake. Findings from some of the sediment cores examined at the Great Lakes indicate that toxaphene has slow degradation rate. The similar concentrations among all the Great Lakes suggest that the main bulk of toxaphene at the Great Lakes had come from the atmosphere.

The fate and sources of atrazine in the Great Lakes can be determined using a dynamic mass balance model. The effectivity of the model depends upon the use of given inputs and losses and the manipulation of independent variables to match model results with measured concentrations. The model has effectively shown that the internal transformation of atrazine is a constant occurrence in the Great Lakes, with Lake Michigan, Huron and Ontario yielding similar transformation rates that ranges from 0.05 to 0.075 yr-1.

A study of the sorption of nonionic hydrophobic organic chemicals to mineral surfaces was found to be dependent on the type of mineral surface and independent of solution pH and the charge and magnitude of sorbent surface charge. This conclusion was reached after different polycyclic aromatic hydrocarbons and chlorobenzenes were subjected to sorption studies on pure mineral substrates, such as alpha-Al2O3 and alpha-Fe2O3, using column chromatography.

The transport of polycyclic aromatic hydrocarbons (PAHs) from the emissions from urban areas around Chicago, IL< and Gary, IN, to Lake Michigan was investigated by measuring the concentration of PAHs in the lake sediments. High concentrations of PAHs from the same location were found, particularly phenanthrene, benzo[b+k]fluoranthane, benzo[a]-pyrene and perylene. The accumulation of these compounds in lake sediments was attributed to historical coal use in IllINNis and extensive steel production in IllINNis and Gary, IN, as a result of in-lake integration processes.

The influence of adsorbent, adsorbate, temperature and relative humidity (RH) on the adsorption process is examined through a study of adsorption to the minerals hematite, corundum and lime. Between 30 and 90% RH, there was an exponential decrease of the adsorption coefficients of all tested compounds on all adsorbents. The influence of RH was even greater below 30%. These results indicate that differences in the surface area-normalized adsorption on different mineral surfaces were most noticeable at low RHs, becoming smaller as RH increases and disappearing when RH neared 100%.

Current spatial distribution of polychlorinated biphenyl (PCB) concentrations in Lake Michigan waters was determined to evaluate time changes in these. Water samples were taken from 11 open water sites in the lake and compared with data from 1980. Findings revealed that PCB concentrations decreased from 1980 to 1991 with a first-order rate constant calculated at -0.078 yr(-1). PCB concentration was also found to be higher in the most southern and southwesterly sites. These also showed different homolog profiles and partitioning behavior than samples taken from other sites.

A study was conducted on the influence of temperature on the degree and rate of sorption in the polycyclic aromatic hydrocarbons naphthalene, phenanthrene and pyrene to low organic carbon aquifer sands. Batch and column sorption experiments were conducted as complimentary approaches to determine equilibrium distribution coefficients and sorption rate constants. Results suggested that thermal gradients may not have significant consequences in majority of saturated subsurface regimes when predicting solute transport.

A study has been conducted to assess the accumulation and diagenesis of selected hydrophobic organic compounds (HOC) in five Lake Ontario sediments cores taken in 1990-1991 through lead dating. The lead profiles showed significant variability among cores, suggesting that particles are mixed and distributed evenly in sediments in the lake basins. They also indicated intraspecific variation in each basin.

The air-water exchange of polychlorinated biphenyls (PCBs) in Lake Michigan was studied in connection with the delivery and removal of semivolatile organic compounds from natural waters. An air-water gas exchange model based on mass transfer coefficients obtained from actual air samples was used to compute the flux of PCBs through the air-side and water-side layers. Results that the PCB fluxes in Lake Michigan is dependent on the water temperature, wind speed and PCB vapor concentrations.

The presence, sources and environmental behavior of the three herbicides used in cropland near Lakes Michigan, Huron, Erie and Ontario were investigated. Specifically, atrazine, alachlor and metolachlor concentrations in Great Lakes samples were measured over a two year period. The results confirm their presence in rivers, groundwaters and their precipitation at concentrations above 1,000-10,000 ng/L.

The instantaneous fluxes and seasonal trends of polychlorinated biphenyl (PCB) congeners across the air-water interface in Lake Superior were examined using a modified two-film gas exchange model. Results revealed that volatilization accounted for most of the air-water exchange of PCBs throughout most of the year in Lake Superior. Gas-phase deposition of PCBs occurs only for several weeks during spring. PCB loss from the water column due to volatilization was greater than the combined PCB loss via sedimentation and outflow.

Polychlorinated biphenyl (PCB) water concentration measurements obtained from Lake Superior during the period 1978-1992 were analyzed to determine what is the major loss process for PCB in the lake. Lake Superior receives most of its PCB input from the atmosphere, while PCB removal is possible via sedimentation, river outflow, volatilization and biological and chemical transformations. Results indicate that PCBs are decreasing in Lake Superior's water column, with volatilization as the main loss process.

Lichen samples from 35 sites in Ontario have been used to look at the possibility of using lichen to monitor airborne deposition of PCB congeners and organochlorine pesticides. The dispersal of semivolatile organic contaminants is thought to be closely linked with terrestrial vegetation, but the study showed that lichen samples can only indicate significant spatial trends, with temporal trends requiring a longer study period than the three years in question. However, air-plant bioconcentration factors could be generally useful in predicting air concentrations of semivolatile organochlorines.

The sorption of hydrophobic organic chemicals to alpha-Al2O3 was studied using the headspace analysis technique. The results showed that benzene interacted weakly with well-characterized aluminum oxide. When the sorption coefficients were extrapolated up to the solids concentrations normally used in batch sorption experiments, the sorption coefficients agreed with reported data.

The volatilization of polychlorinated biphenyls from the Green Bay section of Lake Michigan is studied. Experiments are carried out wherein surface water and air samples are analyzed by means of a series of filtering and decanting techniques and gas chromatography. A stagnant film model is then used to determine the transfer of chemicals across the air-water interface. Results show that the gas transfer flow pattern is from water to air.

The polychlorinated biphenyls over the water of Green Bay, Lake MI and over the surrounding land are studied to determine volatilization properties of semivolatile organic chemicals. Experiments are conducted wherein air and water samples are subjected to various filtering and adsorption procedures. A Maxima 820D datasystem is then employed to obtain the necessary chromatoghraphic data. Results show that atmospheric PCB concentrations are more prevalent over contaminated water than over the surrounding land.