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Polycyclic aromatic hydrocarbons (PAHs) are produced by anthropogenic activities, such as traffic and domestic heating. Due to their adverse effects to humans and natural habitats, the presence of PAHs in the environment needs to be monitored. Plants are known as natural accumulators of persistent organic pollutants (POPs) and can therefore be used for the monitoring of PAHs emitted into the environment. Contamination by PAHs also occurs in the Arctic such as Greenland due to long-range transport through air. However, as anthropogenic activities in the Arctic are increasing, there is a need to investigate the distribution of PAHs due to local emission sources. In this study, we present a systematic sampling approach to identify the influence of PAH sources in an area next to the town of Ilulissat in Greenland. Composite crowberry samples have been collected north of Ilulissat, where the town itself, an incineration site and Ilulissat airport are possible emission sources for PAHs. Matrix solid-phase extraction was used for the extraction of PAHs and the chemical analysis was performed by gas chromatography with mass spectrometry detection (GC-MS). In total, 18 out of 19 investigated PAHs could be detected in Empetrum nigrum in a concentration range of 0.69 to 93.01 μg/kgdry weight. Higher concentrations for most of the targeted PAHs were found close to the suspected emission sources and also along the road connecting them. For pyrene, the correlation between the concentration and the distance from the emission sources could be modelled and visualized using a two-dimensional exponential variogram and ordinary kriging. The range in which the samples were spatially correlated was approximately 500 m. Our results show that local emission sources contribute to the spatial distribution patterns of PAHs. Monitoring of pollution by airborne PAHs is therefore needed even in areas far from major pollution sources such as Ilulissat, Greenland. E. nigrum showed to be a feasible species for biomonitoring of PAHs due to its large abundance in the sampling area and its widespread availability in the Artic region.

The Theory of Sampling as developed by Pierre Gy is a complete theory that describes sampling errors and how to obtain a representative sample. Unfortunately Gy's formula for prediction of the Fundamental Sampling Error (FSE) can be difficult to use in practice, as it is only valid for binary materials with same size distribution of analyte containing fragments and matrix fragments. An extended Gy's formula for estimation of FSE is derived from Gy's definition of constitutional heterogeneity. This formula is exact with no assumptions and allows prediction of FSE for any particulate material with any number of particle classes in contrast to Gy's formula. The difference is that the only assumption made is that the sampled material can be divided into classes with similar properties for the fragments within each class. The extended Gy's formula is validated by model experiments sampling mixtures of 3–7 components with a riffle splitter with 18 chutes. In most cases the observed sampling error was well predicted by the newly derived, extended Gy's formula. However, in some experiments the observed sampling errors were lower than FSE. This can be explained by the sampling paradox, and the effect is calculated by a new function, the Fundamental Sampling Uncertainty, FSU. The observed results are typically in excellent agreement with the predictions (the predicted uncertainties were on average 0.5% points lower than the observed values). The extended Gy's formula described here is ideal for use in teaching of sampling methods because the experiments can be set up using materials with accurately known properties. The proposed new formula allows accurate prediction of FSE and FSU for complex materials that contain more than two types of particles.

Handling and transport of contaminated soil from industrial sites in Denmark requires classification based on concentrations of selected metals and organic contaminants. Reliable soil classification is needed for defensible remedial decision-making. Today’s sampling process in Denmark is based on grab sampling of prescribed standard volumes of soil; 30 tons is typically used as the basic sampling Decision Unit. Soil classification follows a number of varying systems, but classification into five classes (class 0 to class 4) based on analytical results from sub-samples of 50 g is the most common. In this study we investigate the sampling uncertainty obtained by sampling of > 1800 samples at a former industrial site in Copenhagen, Denmark. The aim of the study was to conduct a critical assessment of the current sampling strategy by determination of soil classification errors obtained for duplicate primary samples collected from the same truck- load of soil, but with different distances from the original primary sample. It is also discussed which contaminants are the major parameters responsible for final soil classification designations. The original primary samples for the soil classification were taken at the centre of a 7 × 7 m grid for every 33 cm to a depth of 1 m or 3 m. In addition - for approximately half of the positions - samples were taken at a distance of 1, 2 or 3 m from the original sample. The classifications for the original samples were compared to the classifications for the additional samples in the same Decision Unit (7 × 7 × 0.33 m box) and from duplicate original samples. The results show that at least 50 % of all samples were misclassified, 20 % were mis-classified by two or more classes. This study demonstrates that the risk of misclassification is highest for less mobile parameters, metals and PAHs compared to the volatile organic solvents.

Gy’s formula is a formula to predict the Fundamental Sampling Error (FSE), a part of The Theory of Sampling (TOS) as developed by Pierre Gy. Gy’s formula is only valid for binary materials with the same size distribution of analyte containing fragments and matrix fragments. Unfortunately, the formula has been used without regard to these limitations, and the results have often been erroneous, giving the Theory of Sampling a bad reputation. However, an extended Gy’s formula for estimation of FSE without these restrictions can be derived from Gy’s definition of constitutional heterogeneity. This formula is exact with no assumptions, except that the lot can be divided into classes with fragments with similar properties within each class. The extended formula allows prediction of FSE for any particulate material with any number of particle classes in contrast to Gy’s formula. The extended Gy’s formula is validated by model experiments sampling mixtures of 3 to 7 components with a riffle splitter. In most cases the observed sampling error was well predicted by the newly derived, extended Gy’s formula. However, in some experiments the observed sampling errors were lower than FSE. This can be explained by the segregation paradox, and the effect is calculated by a new function, the Fundamental Sampling Uncertainty (FSU) proposed here. The observed results are now typically in excellent agreement with the predictions (the predicted uncertainties were on average 0.5% points lower than the observed values). The extended Gy’s formula is easy to use. For a material where the analyte is only present in one class of fragments, the only parameters needed for each class are the average mass of a fragment and the mass proportion of the class in the lot. No need to estimate the liberation factor, the size and shape of the fragments and the concentration. If the analyte is present in more than one class, the concentration in each class is needed too. If fragments of a class have similar properties, but not similar size, the granulometric factor is needed though, and an exact formula for a uniform size distribution has been derived. This formula predicts that the granulometric factor g for a wide size distribution is 0.25 in excellent agreement with Gy’s recommendation for this case. The extended Gy’s formula described here is ideal for use in teaching of sampling methods because the experiments can be set up using materials with accurately known properties. The proposed new formula allows accurate prediction of FSE and FSU for complex materials that contain more than two types of particles. It is the hope that the extended Gy’s formula could increase the popularity of TOS.

The Sampling Uncertainty (SU) recently proposed allows the estimation of the sampling uncertainty including the Grouping and Segregation Error (GSE), the Fundamental Sampling Error (FSE) or the Fundamental Sampling Uncertainty (FSU) and the long range sampling errors for 1-dimensional sampling. SU is calculated from the spatial distribution of the analyte in a manner similar to cyclic convolution. For 1-dimensional sampling SU is shown to be better than variogram integration in case of cyclic or non-stationary variations and by being independent of the nugget effect when the nugget effect is close to zero. Three cases will be treated in detail: The problems with a low nugget effect, the effect of autocorrelation on 1-dimensional sampling and the effect of cyclic variations. For the effect of cyclic variations discrete Fourier transform (DFT) analysis is included to explain the findings and to filter the data. Finally, it is shown that DFT and SU give similar results for the cyclic pattern in the data when SU is calculated for a sampling ratio mass(lot)/mass(sample) = 2. Even though SU itself can estimate the sampling uncertainty correctly, it is proposed always to include a variographic analysis and a DFT analysis to characterize the spatial heterogeneity of the data.

The reuse of digested sludge from wastewater treatment plants (WWTPs) as soil fertilizer poses a risk for contamination of soil and water environments. The present study provides a new approach for investigating the exposure of hydrophobic organic chemicals in sewage sludge. The methodology of equilibrium sampling with multiple thicknesses of silicone was successfully validated and applied to complex sludge matrices. Polycyclic aromatic hydrocarbon (PAH) concentrations in silicone ( C silicone ) were determined and compared across four WWTPs. Activity ratios ( AR s), defined as C silicone at equilibrium with digested sludge (final product) over C silicone at equilibrium with secondary sludge (intermediate product), were in the range 0.85–20 with all except one AR >1. These AR s thus revealed increased thermodynamic potential of both parent and alkylated PAHs in digested sludge compared with secondary sludge, and thereby higher exposure of PAHs in sludge after digestion than before digestion. This observation can be explained by the concept of “solvent depletion” as organic matter decreased by a factor of 1.3 during digestion, resulting in reduced sorptive capacity and increased freely dissolved concentrations ( C free ). The PAHs with log K ow > 6 had AR s close to 1.3, whereas PAHs with log K ow AR s than the organic matter decrease factor of 1.3. C free in digested sludge were higher than reported in rural soil and generally consistent with levels reported for Baltic Sea sediment.

A low temperature plasma (LTP) ionization interface between a gas chromatograph (GC) and an atmospheric pressure inlet mass spectrometer, was constructed. This enabled time-of-flight mass spectrometric detection of GC-eluting compounds. The performance of the setup was evaluated by injection of mixtures of common volatile organic compounds. Amounts down to ca. 0.5 ng (on column) could be detected for most compounds and with a chromatographic performance comparable to that of GC/EIMS. In the positive mode, LTP ionization resulted in a compound specific formation of molecular ions M(+•), protonated molecules [M + H](+), and adduct ions such as [(M + O) + H](+) and [M + NO](+). The ion patterns seemed unique for each of the analyzed compound classes and can therefore be useful for identification of functional groups. A total of 20 different compounds within 8 functional groups were analyzed.

To combine capillary electrophoresis (CE) and ion mobility spectrometry (IMS) to setup CE-IMS coupling technique, an effective sheathless electrospray interface was developed in the paper. The capillary was rotated on a fixed connector and tapered by manual gridding on the emery paper to obtain tapered capillary tip with the polyimided layer, geometric symmetry. And then the tapered tip was coated with nickel by a simple electrode-less plating procedure to be electrically conductively, so as to generate the electrospray on the tip. Finanlly, three different ways were evaluated for coupling CE with IMS, and get the relatively more effective interface to combine CE and IMS.

An intact and sealed storage jar known as Jar-35 was found in 2004, south of the Qumran settlement. A previous study identified tartrate in the deposit of the jar, indicating the possible past presence of wine (Buti et al. 2006). However, we cannot confirm this finding. Using liquid and gas chromatography with mass spectrometric detection, no trace of tartaric acid or salts thereof could be detected in our samples. We show that the major component of the deposit is gypsum. No other organic compounds were identified with the methods that we have applied. Both radiocarbon dating of charcoal in the deposit and thermoluminescence dating of the ceramic jar show that it dates to the main period of habitation at Qumran (c. 100 BC to AD 70).

The toxic glycoalkaloids produced by the potato plant (Solanum tuberosum L.) have previously been found in upper soil from a potato field during several months. Further insight into the fate of the glycoalkaloids is needed, as only little information about their degradation in soil is available. Degradation of the glycoalkaloid, alpha-solanine, has been followed for 42d in three agricultural soils with common texture and carbon contents. A similar degradation pattern was found in all soils, and the kinetics was well described by a sum of two first-order equations. Overall, degradation rates for the initial first reaction were in the range 0.22-1.64d(-1). Estimated half-lives were in the range 1.8-4.1d for the three top soils at 15 degrees C; the fastest degradation was observed in the sandy soil. The major proportion of alpha-solanine in the sandy soil was degraded by the fast process, while the proportion was lower for the two other soils. Fast degradation appeared to be related to the presence of low amount of sorbents. Additionally, degradation was followed at 5 degrees C in A- and C-horizon soil from the sandy location, and for both horizons the half-lives were of similar length (4.7-8.7d). For the slow process, degradation rates were in the range 0.000-0.123d(-1), and residuals were still present in all soils and all temperatures at the end of the experiment (d 42). Overall, fast degradation was found in both top- and subsoil even at low temperatures, and the risk for alpha-solanine leaching to the groundwater appears to be low.

This paper presents the first membrane inlet method that can be used together with field portable mass spectrometers for the analysis of semivolatile pharmaceuticals (pethidine, benzophenone, and cocaine) and environmental pollutants (terbutryne and butylated hydroxyl toluene (BHT)) dissolved in organic micro extracts. A microliter of the organic extract is simply injected into a closed hot cell membrane inlet (hc-MIMS), and an electron ionization mass spectrum of the vaporized semivolatile sample molecules can be recorded shortly thereafter. Detection limits at low picomole quantities or low/sub ng/microL concentrations in the extract are demonstrated for solutes in methanol, ethanol, acetone, and toluene. A linear correlation between analyte concentration and signal was found in the range of 1-100 ng/microL, and the relative standard deviation (RSD) was approximately 10%. As a practical example we demonstrate the detection of cocaine in extracts from dried coca leaves. The analysis of organic micro extracts using hc-MIMS represents a considerable extension of the type and complexity of analytes that can be measured using a field portable MIMS system, since it does not require special and field tedious modifications to the standard MIMS system.

Artemisinin, a bioactive compound produced in Artemisia annua L. (sweet wormwood) is used as active ingredient in drugs against malaria. Cultivation of A. annua at field scale implies high amounts of artemisinin produced and potential high losses to soil with impact to vulnerable organisms in soil and leaching to the aquatic environment. A new method was developed for extraction of artemisinin in sandy, clayey and humic soil samples by supercritical fluid extraction (SFE) and determination by HPLC. Optimal SFE conditions were reached using ethanol as modifier at a flow of 0.5 mL min−1 and a total extraction time of 20 min. The HPLC method had linearity up to >535 mg kg−1 for all soil types, limit of detection (LOD) was 13 µg kg−1 soil and limit of quantification (LOQ) was 43 µg kg−1 soil. Recovery for soil samples spiked with artemisinin 1 h before extraction was determined to 70–80%. No matrix effect was observed in the detection. The method enabled quantification of artemisinin in three common soil type...

Fusarium Head Blight (FHB) is a destructive disease that affects the grain yield and quality of cereals. The relationship between the natural defense chemicals benzoxazinoids and the FHB resistance of field grown winter wheat varieties was investigated. FHB resistance was assessed by the inoculation of wheat ears with mixtures of Fusarium avenaceum, Fusarium culmorum, Fusarium graminearum, and Microdochium nivale. The benzoxazinoids detected in the highest concentration were 2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (3.7–9.4 μmol/kg DW) and 2-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (HMBOA, 2.0–11 μmol/kg DW). The cultivars most susceptible to FHB were cvs. Hanseat, Asketis, and Ritmo, while cvs. Petrus, Terra, and Hattrick showed high resistance. 2-O-β- d -Glucopyranosyloxy-4,7-dimethoxy-(2H)-1,4-benzoxazin-3(4H)-one (HDMBOA-glc) and 2-O-β- d -glucopyranosyloxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (HMBOA-glc) were detected. HMBOA-glc was found in higher concentrations than 2-O-β- d -glucopyranosyloxy-2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (DIMBOA-glc). Principal component analyses demonstrated correlation between the susceptibility to FHB and the concentrations of DIMBOA-glc, HMBOA-glc, HMBOA, 2-O-β- d -glucopyranosyloxy-4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one (DIBOA-glc), 2-O-β- d -glucopyranosyloxy-1,4-benzoxazin-3(4H)-one, and 2-O-β- d -glucopyranosyloxy-4-dihydroxy-(2H)-7,8-dimethoxy-1,4-benzoxazin-3(4H)-one (DIM2BOA-glc).

The brominated flame retardants hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) are high-production-volume chemicals. In recent years, their presence has been reported in sediment and biota from the marine environment. In this study, an analytical method was developed for the simultaneous determination of HBCD, TBBPA, and the possible metabolite dimethyl-TBBPA. The method was applied in a preliminary screening of egg, liver, and adipose tissue of marine biota from Greenland and the Faroe Islands. α-HBCD was detected in 35 of 36 analysed samples from the Arctic, indicating a ubiquitous presence of α-HBCD in the environment. β- and γ-HBCD were found in 10 and 14 samples, respectively. TBBPA and dimethyl-TBBPA were not detected in any of the samples indicating limited or no transport of these compounds to remote areas.

The volatilization and secondary deposition of the herbicides prosulfocarb and pendimethalin were measured using passive dosimeters with Chinese cabbage and soil as collective material. Passive dosimeters were placed in the field before spraying and at three distances downwind after spraying. The volatilization of prosulfocarb and pendimethalin determined as dissipation was 80 and 60% of the applied amount from the cabbage surface, while no significant loss was measured from soil surfaces after 48 h. The secondary deposition of prosulfocarb and pendimethalin 25 m from the spray zone was 2 and 4% on the leaf surface as well as on the soil surface. At 5 m distance, 6 and 10% of the field dose of prosulfocarb and pendimethalin could be determined on dosimeters with leaves, and 4 and 8% of the field dose could be determined on soil surfaces.

The toxic glycoalkaloids α-solanine and α-chaconine are produced in all parts of the potato plant, and post-harvest potato tubers may represent a source of soil and water contamination. A new method was developed for extraction and purification of α-solanine in soil samples. Soil samples were extracted with THF : H2O : ACN : CH3COOH (50 : 30 : 20 : 1) and the extract purified by SPE before HPLC determination of α-solanine. The limit of detection was 2.4 mg of α-solanine kg−1 soil. The new procedure was used for determination of α-solanine in spiked soils with varying content of organic matter and texture. Recovery for soil samples spiked with α-solanine 1 h before extraction was 61–68% for soils low in organic carbon (

In the present study the primary drift of 10 herbicides was investigated in five field experiments, and the amount deposited per surface area was quantified outside the application area using simple passive dosimeters. In addition, samples for measuring a possible background value were taken upwind of the sprayed field. Deposits of spray drift were common to all spray equipment and spray was detected up to 150 m off-target. There were deposits of 0.1–9% of the applied amount close to the sprayed field (up to 2 m). But 3 m from the spraying zone deposits were reduced to 0.02–4%. The amounts decreased exponentially when moving away from the field. The differences in drift could be described mainly by the different drop sizes, the wind velocity, the formulation and the filtering effect of vegetation on the sampling area. The tendency of the active ingredients to evaporate could also have an, although less important, influence on the drift. This is a factor, which ought to be exposed to a further study. The findings supported that it is the physical properties of the spray and the conditions of application (i.e. equipment and meteorology) that are the primary determinants of primary drift rather than the chemical property of the pure active ingredients.

In the present study the evaporation of 10 herbicides was investigated during five field experiments, and the amount deposited per surface area was quantified inside the field using simple passive dosimeters consisting of microscope slides placed on plastic lids. On an average basis 90% of the applied amount reached the field. The accumulated evaporation from the microscope slides was largest during the first hours after application, and the losses in 24 h (from 0% for tribenuron-methyl, fluroxypyr-1-methylheptylester and phenmedipham to 80% for prosulfocarb) was similar to other studies of losses from plant surfaces. An indication of a diurnal difference in the evaporation was observed, probably caused by the differences in temperature or by global radiation. The evaporation did not generally correlate to the vapour pressure. The amounts collected at t = 0 on the passive dosimeters were for all field experiments in the same range as the reported amounts applied to the field, and the passive-dosimeters method was found to be a good and reliable method for collection of sprayed pesticides. The advantage of this method was also that it was simple and cheap and easy to set up for screening of evaporation of pesticides from the field after spraying.

This paper compares the extraction effectiveness of six different commonly applied extraction techniques for the determination of PCBs in soil. The techniques included are Soxhlet, Soxtec, ultrasonication extraction, supercritical fluid extraction, microwave-assisted extraction and accelerated solvent extraction. For none of the techniques were the extraction conditions optimized, but instead the extraction parameters were based on the experience from previous successful investigation published by a number of research groups worldwide. In general, all extraction techniques were capable of producing accurate data for one native PCB contaminated soil diluted with another soil sample to obtain two concentration levels. It could therefore be concluded that any of the investigated techniques can be used with success if the extraction conditions applied are chosen wisely.

Leaching to the ground water of metabolites from the herbicide metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5-one] has been measured in a Danish field experiment in concentrations exceeding the European Union threshold limit for pesticides at 0.1 microg/L. In the present work, degradation and sorption of metribuzin and the metabolites desamino-metribuzin (DA), diketo-metribuzin (DK), and desamino-diketo-metribuzin (DADK) were studied in a Danish sandy loam topsoil and subsoil from the field in question, using accelerated solvent extraction and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Fast dissipation of metribuzin and the metabolites was observed in the topsoil, with 50% disappearance within 30 to 40 d. A two-compartment model described degradation of metribuzin and DA, whereas that of DADK could be described using first-order kinetics. Part of the dissipation was probably due to incorporation into soil organic matter. Degradation in subsoil occurred very slowly, with extrapolated half-lives of more than one year. Sorption in the topsoil followed the order DA > metribuzin > DK > DADK. Subsoil sorption was considerably lower, and was hardly measurable for metribuzin and DK. Abiotic degradation was considerably higher in the topsoil than the subsoil, especially concerning the de-amination step, indicating that organic matter may be related to the degradation process. The present results confirm observations of metribuzin and transformation product leaching made in the field experiment and demonstrate the need for knowledge on primary metabolites when assessing the risk for pesticide leaching.

Beta-thujaplicin (beta-TH) is a toxic tropolone derivative present in the heartwood of western red cedar (Thuja plicata) and is used as a preservative and antimicrobial additive in a number of commercial goods. beta-TH released from western red cedar timber used outdoor and from other products containing beta-TH may transfer to soil and leach to groundwater and surface waters. The objective of this study was to quantify the adsorption of beta-TH to goethite as a typical model for geosorbents. Adsorption was studied using pH-adjusted goethite suspensions with solid:solution ratios of 1:500, 0.01 M NaNO(3) electrolyte, and 20 degrees C. beta-TH was determined using a new capillary zone electrophoresis (CZE) method providing a detection limit of 0.21 microM. Near-sorption equilibrium was attained within 48 h. beta-TH showed maximum adsorption at low pH (3.8) and a 70% drop in adsorption from pH 6.2 to 8.8. The Langmuir type adsorption isotherm at pH 5.5 approached a maximum adsorption of 220 micromol/g (= 6.2 micromol/m(2)), which is more than twice the amount of phosphate adsorbed under similar conditions. The affinity of beta-TH for goethite is low as compared with organic ligands such as citrate, oxalate, and 2,4-dihydroxybenzoate. The adsorption data and FTIR analyses indicate that beta-TH is most likely adsorbed as monodentate mononuclear surface complexes at the surface of goethite. Hydrophobic adsorption is thought to contribute to the adsorption, in particular at low pH. The strong adsorption of beta-TH to goethite suggests low mobility in most soil environments, the risk of contamination increasing in soils with high pH (calcareous material), low contents of iron and aluminum oxides, phyllosilicates, and organic matter.

Static extraction, supercritical fluid extraction (SFE), pressurized liquid extraction (PLE) and Soxhlet extraction were compared for simultaneous extraction of di(2-ethylhexyl) phthalate (DEHP) and nonionic surfactants from house dust. Homogenized office floor dust from a vacuum cleaner dust bag (“standard dust”) was used for the evaluation. One portion of the extracts was used for analysis of nonionic surfactants with LC–MS and another portion was used for DEHP analysis with GC–MS. The extraction yield of DEHP was comparable for all the methods whereas SFE and PLE were the most efficient extraction techniques for the nonionic surfactants. The PLE extraction was found most suitable as a routine method for simultaneous extraction of both types of compounds and was used in a field study of floor dust from 15 Danish schools. The mean concentration of DEHP in the school dust samples was ∼4 times higher than observed in other studies of dust from homes in different countries. The concentrations of nonionic surfactants were one order of magnitude lower than soap and linear alkylbenzene sulfonates measured in other studies of floor dust from offices and other public buildings. However, for the first time nonionic surfactants have been identified in house dust.

A solid-phase microextraction (SPME) method was developed for the analysis of acidic pesticide residues in water. The method utilizes in situ derivatization with butylchloroformate (BuCF), followed by on-line SPME extraction using a PDMS fibre, and analysis by GC–MS. Derivatives of the phenoxy acids mechlorprop (MCPP), dichlorprop (DCPP), MCPA and 2,4-D and their phenol degradation products 4-chloro-2-methylphenol and 2,4-dichlorophenol (DCP) were identified. Detection limits at 0.16–2.3 μg/l were achieved. Optimization of derivatization, ion strength, extraction time, SPME-fibre, desorption time and temperature are described. Standard curves in the range 0.5–10.0 μg/l were fitted to a second-degree polynomial. Standard deviation (n=5) was below 10% for the phenol derivatives, but 20–50% for the phenoxy acids. For method verification groundwater samples from a field experiment were screened for content of MCPP and compared to the results from the HPLC analysis. A good agreement was obtained with respect to identification of positive samples, even though concentrations measured by the SPME were lower than with HPLC. Even if the precision and accuracy do not meet the demands for a strictly quantitative analysis, the SPME method is suitable for screening, because it is cheap, it can be automated, and uses smaller amounts of potential harmful solvents. Also, the method is less labour-intensive, as it requires a minimum of sample preparation when compared to traditional analyses. The acidic pesticides bentazon, dicamba, bromoxynil, ioxynil, dinoseb and DNOC were included in the study but could not be analysed by the current method.

The release of chloroform, 1,1,1-trichloroethane, tetrachloromethane, trichloroethene and tetrachloroethene from an organic rich spruce forest soil was studied in laboratory incubation experiments by dynamic headspace analysis, thermodesorption and gas chromatography. Performance parameters are presented for the dynamic headspace system. For spruce forest soil, the results showed a significant increase in chloroform concentration in the headspace under aerobic conditions over a period of seven days, whereas the concentration of the other compounds remained fairly constant. A biogenic formation of chloroform is suggested, whereas for the other compounds anthropogenic sources are assumed. The addition of trichloroacetic acid to the soil increased the release of chloroform from the soil. It is, therefore, suggested that trichloroacetic acid also contributed to the formation of chloroform. Under the experimental conditions, the spruce forest soil released chloroform concentrations corresponding to a rate of 12 microg m(-2) day(-1). Data on chloroform production rates are presented and compared with literature results, and possible formation mechanisms for chloroform are discussed.

Indoor plants can remove volatile organic compounds (VOCs) from the air. The majority of knowledge comes from laboratory studies where results cannot directly be transferred to real-life settings. The aim of this study was to develop an experimental test system to assess VOC removal by indoor plants which allows for an improved real-life simulation. Parameters such as relative humidity, air exchange rate and VOC concentration are controlled and can be varied to simulate different real-life settings. For example, toluene diffusion through a needle gave concentrations in the range of 0.10-2.35 μg/L with deviations from theoretical values of 3.2-10.5%. Overall, the system proved to be functional for the assessment of VOC removal by indoor plants with Hedera helix reaching a toluene removal rate of up to 66.5 μg/m(2)/h. The mode of toluene exposure (semi-dynamic or dynamic) had a significant influence on the removal rate obtained by H. helix.

Leaching of the herbicides atrazine (6-chloro-N2-ethyl-N4-=isopropyl-1,3,5-triazine-2,4-diamine) and hexazinone (3-cyclohexyl-6-dimethylamino- 1-methyl-1,3,5-triazine=2,4(1H,2H)-dione) was measured in samples taken from drainage water from two plantations with 7-10-year-old Abies nordmanniana (Steven) Spach grown on clayey soils. Leaching of atrazine was almost the same in both plantations showing highest concentrations at the beginning of the 2-year sampling period. Leaching of hexazinone from the plantations showed fluctuating concentrations. A relatively simple deterministic model, CMLS1, was chosen to see if existing simulation models could simulate the observed concentrations. An extension was added to the CMLS model in order to simulate dispersion of pesticides in soil. The simulation results of CMLS with dispersion are in better agreement with the observed concentrations.

The increase of agricultural intensity over the last century in rural Denmark has meant that ammonia has been regarded as a significant environmental problem. The deterioration of murals in rural churches is also a matter of concern and focused attention on the potential for ammonia to accelerate damage. Ammonia concentrations measured over 12 months inside and outside nine churches often show a spring maximum outdoors, hinting at the importance of farming activities. The ammonia concentrations are on average some three times greater indoors than outdoors and mass balance calculations suggest that this arises from the decomposition of ammonium nitrate aerosols. The emissions may result from reactions of aerosols deposited at the alkaline walls, which also leads to calcium nitrate becoming the major soluble salt at the very surface layer. The quantities remain small enough, that they probably do not participate in salt damage to the murals.

The amounts of free ions and labile complexes of Pb, Zn and Cd have been determined in a complex organic growth medium by use of anodic stripping staircase voltammetry, ASSV. It was possible to determine the labile fractions of metals and to obtain good correlation with data on the toxicity of the metals to Tetrahymena when using a specific reduction potential ( E s ) for each element, - 600, - 800 and - 1200 mV vs . SCE for Pb, Zn and Cd, respectively. The labile fractions in the organic growth medium were less than 1% for Pb (Pb precipitated), 15% for Zn (as labile complexes) and 30–40% for Cd (as free ions) for total heavy metal concentrations of 0.5m M –2m M . The toxicity to Tetrahymena decreased in the order Cd⪢ Zn⪢ Pb. The effect of Pb was greater than predicted by ASSV, probably because Tetrahymena additionally ingests the lead-containing precipitate and therefore is exposed to concentrations of Pb exceeding those of the soluble species found in the medium. The results stress the importance of using different specific reduction potentials when different elements are compared, instead of one potential common to all elements. The use of a fixed potential may lead to erroneous conclusions regarding the concentrations of labile species in solution.

The fate of glyphosate and its degradation product aminomethylphosphonic acid (AMPA) was studied in soil. Labeled glyphosate was used to be able to distinguish the measured quantities of glyphosate and AMPA from the background values since the soil was sampled in a field where glyphosate had been used formerly. After addition of labeled glyphosate, the disappearance of glyphosate and the formation and disappearance of AMPA were monitored. The resulting curves were fitted according to a new EU guideline. The best fit of the glyphosate degradation data was obtained using a first-order multi compartment (FOMC) model. DT(50) values of 9 days (glyphosate) and 32 days (AMPA) indicated relatively rapid degradation. After an aging period of 6 months, the leaching risk of each residue was determined by treating the soil with pure water or a phosphate solution (pH 6), to simulate rain over a non-fertilized or fertilized field, respectively. Significantly larger (p0.05) amounts of aged glyphosate and AMPA were extracted from the soil when phosphate solution was used as an extraction agent, compared with pure water. This indicates that the risk of leaching of aged glyphosate and AMPA residues from soil is greater in fertilized soil. The blank soil, to which 252 g glyphosate/ha was applied 21 months before this study, contained 0.81 ng glyphosate/g dry soil and 10.46 ng AMPA/g dry soil at the start of the study. Blank soil samples were used as controls without glyphosate addition. After incubation of the blank soil samples for 6 months, a significantly larger amount of AMPA was extracted from the soil treated with phosphate solution than from that treated with pure water. To determine the degree of uptake of aged glyphosate residues by crops growing in the soil, (14)C-labeled glyphosate was applied to soil 6.5 months prior to sowing rape and barley seeds. After 41 days, 0.006 +/- 0.002% and 0.005 +/- 0.001% of the applied radioactivity was measured in rape and barley, respectively.

It is shown that potentially persistent transformation products can be formed from the herbicides bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) and ioxynil (3,5-diiodo-4-hydroxybenzonitrile), and possible leaching to groundwater is discussed. A similar process to the formation of BAM (2,6-dichlorobenzamide) from the herbicide dichlobenil (2,6-dichlorobenzonitrile) can be anticipated as bromoxynil and ioxynil are analogues of dichlobenil and they are degraded by the enzymes nitrilase, nitrile hydratase and amidase. A biodegradation study using cultured Variovorax sp. DSM 11402, a species commonly found in soil, demonstrated that ioxynil and bromoxynil were fully transformed into their corresponding amides in 2–5 days. These amides were not further degraded within 18 days, and formation of other degradation products was not observed. These results are in agreement with biodegradation experiments with dichlobenil. In soil, dichlobenil is transformed into its only observed degradation product BAM, which is persistent and mobile, and has been found in 19% of 5000 samples of Danish groundwater. Variovorax sp. is known to degrade the non-halogenated analogue benzamide, suggesting that degradation of the three amides may be hindered by the halogenated substituents (meta-Br; meta-I; ortho-Cl). This hypothesis is supported by QSAR modelling of fundamental properties. Using a new optimised liquid chromatography–tandem mass spectrometry (LC-MS/MS) method, the sorption and desorption properties of bromoxynil and ioxynil were characterised in sandy topsoil at four concentration levels. The estimated sorption coefficient Kd was 1.4 L kg−1 for bromoxynil and 5.4 L kg−1 for ioxynil, indicating weak to moderate sorption to topsoil. Desorption of the herbicides showed that they were strongly and irreversible bound to the soil (Kdes > Kd). The amount of herbicide desorbed depended on the initial concentration level. At low levels, Kdes values were higher, indicating stronger binding than at higher levels. The isocratic LC-MS/MS method developed for simultaneous detection of bromoxynil, ioxynil and their main degradation products is described. Using negative electrospray ionisation (ESI–), the detection limits were 0.4–1.0 µg L−1, with relative standard deviations of 4–10% (n = 10) using direct injection without clean-up steps. The standard curves showed linearity in the range 5–100 µg L−1 with r2 > 0.992. Copyright © 2006 Society of Chemical Industry

The purpose of the work presented here was to evaluate the influence of solution composition and analyte characteristics on responsiveness to analysis with negative ion electrospray ionization mass spectrometry. The responses of a series of structurally diverse acidic molecules were compared in various solvents. Response was generally observed to be higher in methanol than acetonitrile and response for all analytes was poorer when water was mixed with the organic solvent. A positive correlation between negative ion ESI-MS response and log P was observed when either acetonitrile or methanol was used as the electrospray solvent. This result was expected because analytes with significant nonpolar character should be particularly responsive to ESI-MS analysis due to their higher affinity for electrospray droplet surfaces. It was also predicted that highly acidic analytes would be most responsive to analysis with negative ion ESI-MS due to their tendency to form negative ions. However, for the analytes studied here, acidity was found not to have a consistent influence on ESI-MS response. Many of the highly acidic molecules were quite polar and, consequently, were poorly responsive. Furthermore, the deprotonated molecular ion was detected for a number of molecules with very high pKa values, which would not be expected to form negative ions in the bulk solution. Ultimately, these results indicate that acidity is not a conclusive parameter for prediction of the relative magnitudes of negative ion ESI-MS response among a diverse series of analytes. Analyte polarity does; however, appear to be useful for this purpose.

Static extraction, supercritical fluid extraction (SFE), pressurized liquid extraction (PLE) and Soxhlet extraction were compared for simultaneous extraction of di(2-ethylhexyl) phthalate (DEHP) and nonionic surfactants from house dust. Homogenized office floor dust from a vacuum cleaner dust bag ("standard dust") was used for the evaluation. One portion of the extracts was used for analysis of nonionic surfactants with LC-MS and another portion was used for DEHP analysis with GC-MS. The extraction yield of DEHP was comparable for all the methods whereas SFE and PLE were the most efficient extraction techniques for the nonionic surfactants. The PLE extraction was found most suitable as a routine method for simultaneous extraction of both types of compounds and was used in a field study of floor dust from 15 Danish schools. The mean concentration of DEHP in the school dust samples was approximately 4 times higher than observed in other studies of dust from homes in different countries. The concentrations of nonionic surfactants were one order of magnitude lower than soap and linear alkylbenzene sulfonates measured in other studies of floor dust from offices and other public buildings. However, for the first time nonionic surfactants have been identified in house dust.

A method developed for study of metribuzin degradation in soil is presented. LC-MS-MS and electrospray ionisation was used for analysis of metribuzin and the metabolites deaminometribuzin (DA), diketometribuzin (DK) and deaminodiketometribuzin (DADK). Soil samples were extracted by pressurized liquid extraction using methanol-water (75:25) at 60 degrees C. In general, recoveries were about 75% for metribuzin, DA and DADK and their detection limit in soil was 1.25 microg/kg. Lower sensitivity was observed for DK, with detection limit at 12.5 microg/kg and recovery about 50%.

Samples from a long-term bioremediation experiment contaminated with two crude oils, Arabian Heavy and Gullfax, was used to analyze the compositional change of petroleum hydrocarbons. A time course of five different homologous series of petroleum hydrocarbons were analysed by GC/FID and GC/MS. The homologous series were n-alkanes, acyclic isoprenoids, alkylated naphthalenes, alkylated phenanthrenes, and alkylated dibenzothiophenes. Several biomarker compounds were monitored during the experiment to evaluate the possible use as conserved reference compounds for the quantification of other oil compounds, that is, nor-hopanes, hopanes, methyl-hopanes, steranes, mono- og triaromatic steranes. The 17α(H),21β(H)-hopane was found to be stable toward biodegradation and was used as reference compound. The internal standard quantification method was used to quantify changes of the homologous series of oil compounds, and a graphic presentation was used to compare the decrease of the individual compounds. This was fo...

The ciliate Tetrahymena pyriformis was grown in a peptone medium without added glucose. The interrelationship between increasing cell density and pH of the growth medium was studied from mid-log to the stationary phase, i.e. from 50,000 to 1,000,000 cells/ml, by continuous registration of the pH of the growth medium. The present findings correlate with the known physiological, biochemical, and structural changes occurring in Tetrahymena as it passes through the culture cycle. The ammonia production of the cells and the buffer capacity of the growth medium were determined throughout the growth cycle. The results revealed that the ammonia excreted by the cells can explain the increase in pH of the medium from 6.8 to about 8.3 normally seen during the culture cycle. Moreover, neither the increased pH nor the raised level of ammonia were found to be the responsible factor for cessation of cell proliferation in the stationary growth phase although these factors may affect cell proliferation in concentrations well beyond the range found in normal cultures.

Anodic stripping staircase voltammetry (ASSV) has been tested as a method to determine the concentration of “free” ions and very labile complexes of zinc. These species are thought to be primarily responsible for the toxic effect of zinc on the ciliated protozoan Tetrahymena pyriformis . ASSV and toxicological experiments were performed in an inorganic salt medium and the effects of Cu interference were studied. Even though the ASSV results were encumbered with problems, the results agreed well with the toxicological effects. In contrast, calculations based on the solubility product of Zn 3 (PO 4 ) 2 ·4H 2 O could lead to erroneous results because kinetic and other effects result in very slow precipitation of zinc phosphate at the concentration levels in the salt medium used. In this medium there is a dose-dependent effect of zinc on Tetrahymena which is in agreement with the ASSV data, which indicate that all the zinc is in a labile form. The study emphasizes the importance of using experimental determinations in preference to theoretical models, which may predict quite erroneous results.

Rapid-scan staircase voltammetry is used to strip lead plated on a rotating mercury film electrode. With potential steps of 10 mV every 64 μs, the entire stripping of the metals is made in only 4 ms. Noise is reduced by averaging several current measurements on each step. The method allows quantification of 0.1 μg l−1 lead within a total time to less than 4 min. Because of the rapid scan, the rotation of the electrode can continue during the stripping step. Oxygen does not affect the measurements although a small decrease in current is observed. The method is tested on a sample of sea water. Some results are also given for cadmium.

The effect of land use (forest and grassland) on the deposition and mobility of Pb and Cd has been studied by extraction with 1M HCl, 1M NH4Ac/HAc and 1M NH4Ac. The soils were described pedologically and the main physical and chemical parameters were determined. The Pb concentration in the A horizon is higher in the profile under forest than in the profile under grassland. We assign this difference to the filter action of the forest. The Cd concentration is highest in the grassland profile because the forest soil is more degraded and Cd is leached to a higher degree in this soil. Both metals are more mobile (easier to extract) in the forest because the forest soil is most acidic, and because a greater part is bound to organic compounds (humic and fulvic acids) which are more abundant in the forest than in the grassland. The concentrations of Pb and Cd in the A horizons are 26 ppm and 0.1 ppm under the forest and 9 ppm and 0.2 ppm under grassland, respectively. Verteilung und Konzentration von Pb und Cd in zwei Parabraunerden unter Weide und Wald in Danemark Die Wirkung der Bodennutzung (Wald und Weide) auf die Deposition und die Mobilitat von Pb und Cd wurde durch Extraktion mit 1M HCl, 1M Essigsaure/Ammoniumacetat und 1M Ammoniumacetat untersucht. Die Boden werden pedologisch beschrieben und die physikalischen und chemischen Kennwerte bestimmt. Die Pb- Konzentration des A-Horizontes ist unter Wald hoher als unter Weide, was wir auf eine Filterwirkung des Waldes zuruckfuhren. Die Cd-Konzentration ist unter Weide hoher, da der Waldboden starker versauert ist, und somit in diesem Boden Cd in hoherem Grad ausgewaschen wird. Die beiden Metalle sind im Wald verlagerbarer (leichter zu extrahieren), da der Waldboden sauerer ist, und da ein groserer Teil an organische Substanzen (Huminsauren und Fulvosauren), die in groserer Menge im Wald als in der Weide vorhanden sind, gebunden wird. Die Pb- und Cd- Konzentrationen des A-Horizontes betragen 26 mg/kg und 0.1 mg/kg im Wald bzw. 9 mg/kg und 0.2 mg/kg in der Weide.