Native oxy-PAHs, N-PACs, and PAHs in historically contaminated soils from Sweden, Belgium, and France: their soil-porewater partitioning behavior, bioaccumulation in Enchytraeus crypticus, and bioavailability.

Soil quality standards are based on partitioning and toxicity data for laboratory-spiked reference soils, instead of real world, historically contaminated soils, which would be more representative. Here 21 diverse historically contaminated soils from Sweden, Belgium, and France were obtained, and the soil-porewater partitioning along with the bioaccumulation in exposed worms (Enchytraeus crypticus) of native polycyclic aromatic compounds (PACs) were quantified. The native PACs investigated were polycyclic aromatic hydrocarbons (PAHs) and, for the first time to be included in such a study, oxygenated-PAHs (oxy-PAHs) and nitrogen containing heterocyclic PACs (N-PACs). The passive sampler polyoxymethylene (POM) was used to measure the equilibrium freely dissolved porewater concentration, Cpw, of all PACs. The obtained organic carbon normalized partitioning coefficients, KTOC, show that sorption of these native PACs is much stronger than observed in laboratory-spiked soils (typically by factors 10 to 100), which has been reported previously for PAHs but here for the first time for oxy-PAHs and N-PACs. A recently developed KTOC model for historically contaminated sediments predicted the 597 unique, native KTOC values in this study within a factor 30 for 100% of the data and a factor 3 for 58% of the data, without calibration. This model assumes that TOC in pyrogenic-impacted areas sorbs similarly to coal tar, rather than octanol as typically assumed. Black carbon (BC) inclusive partitioning models exhibited substantially poorer performance. Regarding bioaccumulation, Cpw combined with liposome-water partition coefficients corresponded better with measured worm lipid concentrations, Clipid (within a factor 10 for 85% of all PACs and soils), than Cpw combined with octanol-water partition coefficients (within a factor 10 for 76% of all PACs and soils). E. crypticus mortality and reproducibility were also quantified. No enhanced mortality was observed in the 21 historically contaminated soils despite expectations from PAH spiked reference soils. Worm reproducibility weakly correlated to Clipid of PACs, though the contributing influence of metal concentrations and soil texture could not be taken into account. The good agreement of POM-derived Cpw with independent soil and lipid partitioning models further supports that soil risk assessments would improve by accounting for bioavailability. Strategies for including bioavailability in soil risk assessment are presented.

Antiestrogenicity and estrogenicity in leachates from solid waste deposits.

A great deal of effort has been devoted to developing new in vitro and in vivo methods to identify and classify endocrine disrupting chemicals that have been identified in environmental samples. In this study an in vitro test based on recombinant yeast strains transfected with genes for the human estrogen receptor α was adapted to examine the presence of estrogenic and antiestrogenic substances in six Swedish landfill leachates. Antiestrogenic effects were measured as inhibition of the estradiol induced response with the human estrogen receptor α, and quantified by comparison with the corresponding inhibitory effects of a known antiestrogen, hydroxytamoxifen. The estrogenicity was within the range of that determined in domestic sewage effluents, from below the limit of detection to 29 ng estradiol units L(-1). Antiestrogenicity was detected in some of the investigated landfill leachates, ranging between <38 and 3800 µg hydroxytamoxifen equivalents L(-1). There was no apparent relation between the type of waste deposited on the landfills and the antiestrogenic effect. Fractionation of a landfill leachate showed that estrogenic compounds were located in two dominant fractions. Three estrogenic compounds were found that accounted for the estrogenic activity in extracts of leachates: bisphenol A, estradiol, and ethinylestradiol. The bisphenol may have been released from decomposing plastic waste and the estrogenic steroids from earlier deposits of municipal sewage sludge and pharmaceutical waste. Fractionation of leachates from three parts of a landfill showed that the antiestrogenic activity was distributed in at least four fractions and somewhat different in different flows of leachate. This indicated a heterogeneous mixture of antiestrogenic substances.

Removal of estrogenicity in Swedish municipal sewage treatment plants.

The human estrogen receptor alpha-test, hosted in a yeast strain, was used to quantify estrogenicity in three-week composite samples of untreated and treated effluents from 20 Swedish municipal sewage treatment plants. The treatment plants were selected to represent different treatment processes regarding chemical precipitation and microbial procedures. The discharge from Swedish domestic sewage treatment plants contained estrogenic compounds corresponding to <0.1-15 ng estradiol equivalents/L. Low levels of estrogenic activity were also found in a river receiving municipal effluents, 3.5-35 km downstream the outlet from a sewage treatment works. The range of estrogenicity in untreated, raw sewage effluents was found to be 1-30 ng estradiol equivalents/L. Generally, wastewater treatment reduced the estrogenicity and extended biological treatment was most effective in its removal. Activated sludge treatment tended to be more effective than trickling filters, whereas chemical precipitation using iron or aluminium salts without biological treatment showed little effectivity. The study showed that treatment methods in current use are able to eliminate or largely reduce estrogenicity in domestic wastewater.

Estrogenicity in bile of juvenile rainbow trout as measure of exposure and potential effects of endocrine disruptors.

Estrogenicity in the bile of juvenile rainbow trout exposed to effluents from municipal sewage treatment plants and various industries was assayed by using a recombinant yeast strain containing the human estrogen receptor alpha gene. Estrogenicity in bile also was measured after deconjugation of steroids to provide an estimate of the exposure and as an endpoint for potential effects on the organism. In unexposed fish or fish exposed for three weeks at control localities, 0.5 to 9 ng of estradiol equivalents (EEq) were found per gram of bile (ng EEq/g bile). Fish exposed for three weeks in cages placed in the receiving waters near outlets of municipal effluent had an average activity of 26 ng EEq/g bile. Fish exposed to undiluted sewage water in aquaria had a bile estrogenicity of 51 to 87,000 ng EEq/g bile. Unconjugated estrogens contributed only 8% or less to the estrogenicity in bile of fish exposed to municipal effluents. Municipal sewage effluents were more estrogenic than the industrial effluents that were investigated. Estrogenicity in bile was compared to that in extracts of wastewater by using the same receptor assay, and to vitellogenin induction in the plasma of the same fish. Bile estrogenicity proved to be a useful and sensitive (internal) measure of exposure and indicated its potential for the display of biological effects as a complement or replacement of more laborious assays.

Accumulation of polycyclic aromatic hydrocarbons from creosote-contaminated soil in selected plants and the oligochaete worm Enchytraeus crypticus.

The accumulation of PAHs from a creosote-contaminated soil was examined in laboratory experiments using English ryegrass (Lolium perenne), white clover (Trifolium repens) and radish (Raphanus sativus), and the oligochaete worm Enchytraeus crypticus. Toxicity to the plants and the worms was assessed, and a soil sample mixed with calcined sand was used for accumulation experiments to avoid interference from toxicity in the soil. Accumulation of potentially carcinogenic PAHs varied among the plants, and there was a linear relation between concentrations of PAHs in the soil and in the plants. Correlations between values of the biota-soil accumulation factors and octanol-water partition coefficients, or water solubility varied among the plants and were rather weak, so that lipophilic character or water solubility of the PAHs alone cannot explain PAH accumulation. Accumulation of carcinogenic PAHs from the soil, in the presence of the other PAHs was greatest for Trifolium repens. PAHs were accumulated in the oligochaete worm (Enchytraeus crypticus), and biota-soil accumulation factors exceeded those for the plants. It is suggested that site-specific evaluation of contaminated sites should include not only chemical analysis and evaluation of toxicity but also accumulation of contaminants into biota such as plants and worms.

In vitro androgenicity in pulp and paper mill effluents.

Pulp and paper mill effluents were examined for in vitro androgenicity using a recombinant yeast-based androgen receptor assay. Low levels of androgenic effects were detected in extracts of some effluents after activated sludge treatment. Yeast cell growth cell was inhibited in some samples, and this interfered with the androgenic response. Solid-phase fractionation revealed androgenicity after partial separation of components in the effluents. Comparison of levels in untreated effluent and in effluent treated in an aerated lagoon showed that this treatment had only a marginal effect on androgenicity. An assay of the fractions eluted with increasing concentrations of methanol showed that androgenic compounds were low to moderately lipophilic. In an attempt to identify these compounds, a number of wood-related compounds (guaiacol, vanillin, beta-sitosterol, betulin, pinosylvin-O-methyl ether, and a wood extract enriched in lignans) were examined but were found not to be androgenic. Raw process water was not androgenic, but water from a highly humified lake and process water from the production of pulp from partly decayed wood had low androgenicity. It therefore can be plausibly suggested that the androgens originated in decaying wood. An assay of androgenicity in the bile of juvenile rainbow trout exposed to effluents for 3 weeks showed increased dose-dependent levels of androgens after enzymatic hydrolysis of hormone conjugates.

Occurrence and some properties of the androgenic activity in municipal sewage effluents.

Androgenicity was tested in municipal effluents before and after treatment in sewage treatment plants using different treatment methods. The activity was tested with a recombinant yeast strain transfected with the gene for the human androgen receptor. Fractionation of effluents showed some basic properties of compounds with androgenic activity. Effluents from Swedish domestic sewage treatment plants contained compounds with androgenic effects. Levels varied from 0-160 ng dihydrotestosterone (DHT) equivalents/L. The androgenicity was higher in untreated effluents and removals of 26 and 42% for STWs without secondary treatment and 96- > 99% were recorded for STWs with secondary and tertiary treatment. As with estrogens in municipal effluents, STWs using biological treatment such as activated sludge and solid supported microbial processes were more effective in reduction of androgenic activity. Plants using only precipitation methods removed less of the activity. The androgens were composed of at least three individual compounds, similarly or less lipophilic than DHT.

Assessment of androgenicity in leachates from Swedish landfills and treatments for its elimination.

An in vitro recombinant yeast strain, transfected with the human androgen receptor was used to assess androgenic hormone disrupting potencies in leachates from Swedish landfills. It was shown that components in extracts of these affected the androgenic receptor and promoted a response in the beta-galactosidase marker system. Levels were within the range of those determined for domestic sewage effluents but lower than the highest levels found in an industrial effluent. These leachates finally enter receiving waters with or without wastewater treatment. Evidence was found for transformation during some of the wastewater treatments.