Nonylphenols (NPs) have been reported to disrupt endocrine function and sexual development in aquatic organisms at low concentrations. Environmental NP burdens are predominantly derived from degradation of nonylphenol polyethoxylate surfactants. We detected NPs in discharge‐associated riverine sediments adjacent to 11 of 20 active sewage treatment plants (STPs) at concentrations up to 12,400 μg/kg. While most previous studies have focused on STPs, nonylphenols were observed in association with a variety of outfall types. The highest sediment burden, 14,100 μg/kg, was detected near a federal facility's stormwater discharge. Of 75 sediments examined from 67 sites, 45% contained NP concentrations >5 μg/kg; median concentration in these NP‐positive sediments was 369 μg/kg. Other surfactant‐derived alkylphenolic compounds, specifically 4‐tert‐octylphenol and 4‐cumylphenol, were observed in two sediments at 8,220 and 70,000 μg/kg, respectively. The maximum NP concentration detected in an effluent, 6,300 μg/L, was from a shipyard oil/water separator. Nonylphenols were detected (> 1.0 μg/L) in 20% of the 59 effluents examined; 10% exceeded 10 μg/L. Sediments sampled near a STP that had ceased treatment operations 20 years prior contained 54,000 μg/kg, indicative of long‐term NP residence. Results indicate that NPs may be released from diverse sources, concentrate in associated sediments, and persist therein for extended periods.

Immunoassays based on monoclonal antibodies (mAbs) are highly sensitive for the detection of polycyclic aromatic hydrocarbons (PAHs) and can be employed to determine concentrations in near real-time. A sensitive generic mAb against PAHs, named as 2G8, was developed by a three-step screening procedure. It exhibited nearly uniformly high sensitivity against 3-ring to 5-ring unsubstituted PAHs and their common environmental methylated PAHs, with IC50 values between 1.68–31 μg/L (ppb). 2G8 has been successfully applied on the KinExA Inline Biosensor system for quantifying 3-5 ring PAHs in aqueous environmental samples. PAHs were detected at a concentration as low as 0.2 μg/L. Furthermore, the analyses only required 10 min for each sample. To evaluate the accuracy of the 2G8-based biosensor, the total PAH concentrations in a series of environmental samples analyzed by biosensor and GC-MS were compared. In most cases, the results yielded a good correlation between methods. This indicates that generic antibody 2G8 based biosensor possesses significant promise for a low cost, rapid method for PAH determination in aqueous samples.

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Rapid, on-site, quantitative assessments of dissolved polycyclic aromatic hydrocarbons (PAHs) were demonstrated for two field applications. The platform, a KinExA Inline Sensor (Sapidyne Instruments), employed the monoclonal anti-PAH antibody, 7B2.3, which has specificity for 3- to 5-ring PAHs. A spatial study was conducted near a dredging site where contaminated sediments were being removed, and a temporal study was performed during a rainfall event. Most importantly, the generation of near real-time data guided management decisions in the field and determined proper sampling protocols for conventional analyses. The method was able to determine PAH concentrations as low as 0.3 µg/L, within 10 min of sample acquisition, and to assess 80+ samples (not including standards and blanks) in less than 3 d. These results were compared with a laboratory-based gas chromatography-mass spectrometry method in which a wide array of PAHs, including alkylated homologs, were examined. This system shows great promise as a field instrument for the rapid monitoring of PAH pollution.

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Both exposure duration and concentration determine the lethal consequences of polycyclic aromatic hydrocarbons (PAHs) released during oil spills. Many factors, such as weathering, tidal transport, and addition of surfactants, can change the composition of individual dissolved compounds and the duration over which an individual is exposed. Conventional toxicity testing methods produce effect metrics, such as the median lethal concentration (LC50), that are not applicable to predicting mortality at all toxicant exposure durations that are likely to occur during a spill. In the present study, survival time models were developed that explicitly include toxicant exposure duration and concentration to predict time-to-death for grass shrimp (Palaemonetes pugio) exposed to three PAHs (1-ethylnaphthalene, 2,6-dimethylnaphthalene, and phenanthrene) commonly found in the water-soluble fraction derived from oil. Conventional 48-h LC50s also were calculated for the compounds (ethylnaphthalene, 295 microg/L; dimethylnaphthalene, 500 microg/L; and phenanthrene, 360 microg/L). In contrast to LC50s, survival models and associated response surfaces can be used to predict the proportions of shrimp that will die at various times throughout the exposure period.

Johansson, H.; Lindqvist, 0.; Birgitta, T. Occurrence and Turnover of Mercury in the Environment. Report 3524; mercury report no. m Polychlorinated terphenyls (PCTs) are structurally similar to polychlorinated biphenyls (PCBs) and have been used in analogous applications. Aroclor 5432, a PCT formulation whose congeners contain predominantly two to five chlorines, was detected in sediments and oysters from a saltmarsh creek and an adjacent Chesapeake Bay tributary, Back River. Reports of the occurrence of Aroclor 5432 are virtually nonexistent, although sporadic reports of the more highly chlorinated PCT formulation Aroclor 5460 have been published. Capillary gas chromatography with electrolytic conductivity detection was used for quantitation. Identifications were confirmed by both electron ionization and negative chemical ionization mass spectrometry. Sediment concentrations detected were as high as 250000 pg/kg (dry-weight basis). Oysters collected from these areas contained up to 35 OOO pg/ kg. This value is equivalent to 6300 pg/kg, on a wet-weight basis, and exceeds the applicable US. limit for PCBs in edible shellfish by more than a factor of 3.

Nitroaromatics are common pollutants of soil and groundwater at military installations because of their manufacture, storage, and use at these sites. Long-term monitoring of these pollutants comprise a significant percentage of restoration costs. Further, remediation activities often have to be delayed, while the samples are processed via traditional chemical assessment protocols. Here we describe a rapid (<5 min), cost-effective, accurate method using a KinExA Inline Biosensor for monitoring of 2,4,6-trinitrotoluene (TNT) in field water samples. The biosensor, which is based on KinExA technology, accurately estimated the concentration of TNT in double-blind comparisons with similar accuracy to traditional high-performance liquid chromatography(HPLC). In the assessment of field samples, the biosensor accurately predicted the concentration of TNT over the range of 1-30,000 microg/L when compared to either HPLC or quantitative gas chromatography-mass spectrometry (GC-MS). Various pre-assessment techniques were explored to examine whether field samples could be assessed untreated, without the removal of particulates or the use of solvents. In most cases, the KinExA Inline Biosensor gave a uniform assessment of TNT concentration independent of pretreatment method. This indicates that this sensor possesses significant promise for rapid, on-site assessment of TNT pollution in environmental water samples.