Christian Schaffner

Poly cyclic aromatic hydrocarbons in Recent lake sediments—II. Compounds derived from biogenic precursors during early diagenesis

Abstract Five groups of polycyclic aromatic hydrocarbons (PAH) thought to be derived by early-diagenetic transformations of biogenic precursors are apparently present in Recent sediments of four lakes (Lake Lucerne. Lake Zurich, and Greifensee. Switzerland, and Lake Washington, northwest U.S.A.) These natural PAH include: 1. (1) perylene. 2. (2) an extended series of phenanthrene homologs. 3. (3) retene and pimanthrene derived from diterpenes. 4. (4) a series of tetra- and pentacyclic PAH derived from pentacyclic triterpenes of the amyrin-type. 5. (5) tetra- and pentacyclic PAH formed from pentacyclic triterpenes with five-membered E-rings. Since these PAH are abundant in very young sediment layers, the transformation reactions involved appear to be faster than previously thought and may be microbially mediated. There is no evidence that anthropogenic or petrogenic sources can account for the distributions of these groups of PAH in cores of Recent lake sediments.

Behaviour of alkylphenol polyethoxylate surfactants in the aquatic environment—II. Occurrence and transformation in rivers

The behaviour of nonylphenol polyethoxylate surfactants (NPnEO) and their metabolites in the Glatt River, Switzerland was studied. Discharge of secondary effluents from municipal sewage plants into the river was the predominant source of the investigated compounds. The majority of nonylphenolic compounds in the Glatt River were in the form of persistent metabolites, the most abundant being nonylphenoxy carboxylic acids. Distribution of the various classes of nonylphenolic compounds in the river was influenced to differing extents by biological and physico-chemical processes and was dependent on the compound class and the season. Biotransformation appears to be the predominant mechanism determining the fate of nonylphenolic compounds. High concentrations of lipophilic metabolites in river sediments indicate the importance of physico-chemical processes on the distribution of the nonylphenolic chemicals in natural waters.

Polycyclic aromatic hydrocarbons in Recent lake sediments—I. Compounds having anthropogenic origins

Abstract Polycyclic aromatic hydrocarbons (PAH) in sediment cores from Lake Lucerne, Lake Zurich, and Greifensee, Switzerland, and Lake Washington, northwest U.S.A., have been isolated, identified and quantified by glass capillary gas chromatography and gas chromatography/mass spectrometry. Surface sediment layers are greatly enriched in PAH—up to 40 times—compared to deeper layers. In addition, concentration increases in upper sediments generally correspond to increasing industrialization and urbanization in the catchment basins of the lakes. Few PAH could be detected in pre-industrial revolution sediments, indicating that background levels for most PAH in aquatic sediments are extremely low. These results are consistent with an anthropogenic source for most of the aromatic hydrocarbons present in the modern sediments. A comparison of PAH distributions in the sediments and in possible source materials shows that urban runoff of street dust may be the most important PAH input to these lacustrine sediments. There is evidence that a significant contribution to the PAH content of street dust comes from material associated with asphalt.

Persistent organic chemicals in sewage effluents: I. Identifications of nonylphenols and nonylphenolethoxylates by glass capillary gas chromatography / mass spectrometry

Abstract Nonylphenols and nonylphenolethoxylates with one, two, and three oxyethylene groups were identified in effluents from activated sludge sewage treatment plants. The complex mixtures of isomers are considered to be refractory metabolites of nonionic detergents.

BEHAVIOUR OF ALKYLPHENOL POLYETHOXYLATE SURFACTANTS IN THE AQUATIC ENVIRONMENT--III . OCCURRENCE AND ELIMINATION OF THEIR PERSISTENT METABOLITES DURING INFILTRATION OF RIVER WATER TO GROUNDWATER

Abstract The behaviour of various persistent metabolites derived from nonylphenol polyethoxylate (NPnEO) surfactants was studied during infiltration of river water to groundwater at two field sites situated in the northern part of Switzerland (Glatt River and Sitter River). Nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO), nonylphenoxy acetic acid (NP1EC) and nonylphenoxy(ethoxy) acetic acid (NP2EC) were observed in the two investigated rivers at relatively high concentrations with average values of the individual types of nonylphenolic compounds ranging from 1.8 to 25 μg/l. The average concentrations of NP, NP1EO and NP2EO in groundwater were significantly lower (range NP1EO > NP > PCP > NP1EC = NP2EC.

Fate of β-blocker human pharmaceuticals in surface water: comparison of measured and simulated concentrations in the Glatt Valley Watershed, Switzerland.

This study focused on the occurrence and fate of four beta-blockers (atenolol, sotalol, metoprolol, propranolol) in wastewater and surface water. Measured concentrations were compared with predicted concentrations using an implementation of the geo-referenced model GREAT-ER for the Glatt Valley Watershed (Switzerland). Particularly, the question was addressed how measured and simulated data could complement each other for the exposure assessment of human pharmaceuticals and other micropollutants entering surface water through wastewater treatment plants (WWTP). Concentrations in the Glatt River ranged from <LOQ to 83 ng L(-1) with the highest concentrations found for atenolol. Higher loads were measured on days with combined sewer overflow events during high flow conditions. GREAT-ER was able to predict spatially resolved river concentrations based on average consumption and excretion data, removal in wastewater treatment plants (WWTPs) and dissipation and degradation processes in surface water within a factor of 2. These results indicate that modelling might be sufficient to estimate daily average exposure concentrations for compounds that are either recalcitrant or whose degradation and sorption behaviour can be predicted with confidence based on laboratory experiments. Chemical measurements, in contrast, should be reserved for assessing point sources, investigating mechanisms which lead to short-term temporal fluctuations in compound loads, and determining in-situ degradation rates in conjunction with modelling.

Perylene in sediments from the Namibian Shelf

Abstract Sediments from cores collected at two sites in the Namibian Shelf area offshore of southwest Africa have been analyzed for perylene. In all samples, perylene was abundant and was the only high molecular weight polycyclic aromatic hydrocarbon present. Concentrations ranged from 170ng perylene/g dry sediment to 820ng/g and showed a gradient toward maximum concentrations in the deeper core sections. These results lead to one of two possible and somewhat contradictory conclusions: 1. (1) if the input of terrigenous material into these sediments is in fact minimal, then an aquatic rather than terrestrial precursor for perylene is indicated, or 2. (2) there is indeed more terrestrial matter accumulating in Namibian Shelf sediments than generally assumed.

Benzotriazole is antiestrogenic in vitro but not in vivo

Benzotriazole (BT) is an anticorrosive agent well known for its use in aircraft deicing and antifreeze fluids but also used in dishwasher detergents. It is highly persistent in the environment; therefore, BT is frequently found in runoff emanating from large airports as well as in the surrounding groundwater. In addition, BT has recently been found to be ubiquitous in Swiss wastewater treatment plant effluents and their receiving waters; however, very little chronic toxicity data is available on which to base a sound ecological risk assessment of this chemical. In vitro assays conducted using a recombinant yeast (anti-) estrogen assay indicated that BT possessed clear antiestrogenic properties. This chemical was approximately 100-fold less potent than Tamoxifen, which was used as a positive control. A subsequent in vivo study, however, involving analysis of vitellogenin induction and somatic indices in adult fathead minnows (Pimephales promelas) exposed to BT at concentrations of 10, 100, and 1,000 mug/L for two weeks showed no evidence of antiestrogenic activity by this compound. The possibility exists that higher concentrations of BT may yet induce the type of activity observed in vitro, although the concentrations used here already far exceed those reported in surface-water samples. Furthermore, adverse effects may be observed in fish or other organisms exposed to BT for a longer period than employed here, although such studies are costly and unlikely to be included in standard risk assessment procedures. A rigorous investigation of the chronic toxicity of BT is imperative.

Groundwater contamination by volatile halogenated alkanes: abiotic formation of volatile sulfur compounds under anaerobic conditions.

The investigation of a groundwater contamination caused by a leaking wastewater tank of a chemical plant revealed that in groundwaters, under highly reducing conditions in the presence of hydrogen sulfide, certain volatile bromo- and chloroalkanes may undergo second-order nucleophilic substitution reactions yielding very persistent and hazardous volatile sulfur-containing compounds including dialkyl sulfides. Rate constants determined in the laboratory indicate that these nucleophilic substitution reactions may compete with hydrolysis, even at the low hydrogen sulfide concentrations typically encountered in the aquatic environment.

Influences of sedimentary organic matter quality on the bioaccumulation of 4‐nonylphenol by estuarine amphipods

Nonylphenol (NP) is a moderately persistent, hydrophobic chemical with endocrine-disrupting and acute narcotic effects in aquatic biota. Concern exists about the ultimate fate of NP in aquatic ecosystems and the potential for bioaccumulation by benthic biota from the sediment with the potential for further transfer to higher trophic levels. Our goals were to determine if benthic amphipods bioaccumulate significant amounts of NP from sediment and to determine how additions of organic matter influence NP bioaccumulation by amphipods. Estuarine sediment was spiked with 14C-NP and enriched with two types of organic carbon (OC) sources of different nutritional qualities. Macrophytic algae (Ulva species) were used as a labile and nutritious OC source. Wood lignins were used as a refractory and low-nutrition OC source. Nonylphenol bioaccumulation was measured in Eohaustorius estuarius, Grandidierella japonica, and Corophium salmonis after 16 d of exposure. Nonylphenol accumulation was inversely proportional to OC quantity, but was unaffected by OC nutritional quality. Significant differences were found in the accumulation patterns between the three amphipod species. Mean biota-sediment accumulation factors ranged from 8.1 to 33.9 in E. estuarius, from 4.6 to 17.2 in G. japonica, and averaged 7.1 in male C. salmonis and 16.0 in female C. salmonis. These accumulation factors indicate that estuarine amphipods could constitute an important source of NP to higher trophic levels, such as juvenile fish.