Biomedical subjects

Kees Booij

Publications and source records attributed to Kees Booij.

14 recordsLinked to original sources

PubMed2006

Modelling and field application of the Chemcatcher passive sampler calibration data for the monitoring of hydrophobic organic pollutants in water.

Passive sampling of dissolved pollutants in water has been gaining acceptance for environmental monitoring. Previously, an integrative passive sampler consisting of a C18 Empore disk receiving phase saturated with n-octanol and fitted with low density polyethylene membrane, was developed and calibrated for the measurement of time weighted average (TWA) concentrations of hydrophobic pollutants in water. In this study, the exchange kinetics were modelled to obtain a better understanding of the mechanism of the accumulation process and to enable the measurement of TWA concentrations of hydrophobic pollutants in the field. An empirical relationship that enables the calculation of in situ sampling rates of chemicals using performance reference compounds was derived and its application was demonstrated in a field study in which TWA aqueous concentrations estimated from sampler data for target analytes were compared with TWA concentrations obtained from spot samples of water collected regularly during the sampler deployment period.

Calibration↗

PubMed2006

Environmental monitoring of hydrophobic organic contaminants: the case of mussels versus semipermeable membrane devices.

Concentrations of hydrophobic chemicals in mussels and semipermeable membrane devices (SPMDs) from nine studies published over the past decade, amended with new data obtained in the Scheldt-North Sea area, were assessed to understand the similarities and differences between these sampling matrixes. A model was developed to describe the concentration ratios, using literature values of elimination rate constants and steady-state accumulation factors of both samplers as key parameters. The model could successfully describe the results of seven studies. Differences in concentration ratios among these studies were related to the variability of mussel bioaccumulation factors (BAFs) and water sampling rates of SPMDs. For two studies, the model could only describe the data by adopting unrealistically high water sampling rates, and for one study there were not enough data to test the model. We argue that SPMDs will generally yield more reliable estimates of exposure concentrations than mussels, because in situ BAF values are difficult to estimate, whereas the in situ exchange kinetics of SPMDs can be quantified by measuring the dissipation rates of performance reference compounds. The implications of the results for future and existing monitoring programs are discussed.

Animals↗

PubMed2006

Little effect of excessive biofouling on the uptake of organic contaminants by semipermeable membrane devices.

The effects of water flow rate and antifouling agents on the extent of biofouling and on the uptake of non-polar organic contaminants by semipermeable membrane devices (SPMDs) were studied during four field experiments in the Western Wadden Sea. Biofouling densities on the sampler surface ranged from 0.3 to 16g dry weight dm(-2). Water sampling rates were estimated from the dissipation rates of performance reference compounds (PRCs). The antifouling agents Irgarol and capsaicin (33 mg per ml triolein) had no noticeable effect on the extent of fouling, and caused only a 5-10% increase in the absorbed amounts. Enhanced flow rates had only a minimal effect on the amount of biofouling, but caused the water sampling rates to increase by a factor of 1.2-2. Increases in PRC-derived sampling rates were reflected by increases in the absorbed amounts for compounds that were in the linear uptake stage of the sampling process. The results imply (1) that extreme biofouling does not always result in reduced sampling rates, (2) that extreme biofouling does not preclude the existence of flow effects on the sampling rates, and (3) that differences in uptake rates are quantitatively reflected by the dissipation rates of PRCs.

Hydrocarbons, Chlorinated↗

PubMed2005

Passive air sampling theory for semivolatile organic compounds.

The mathematical modelling underlying passive air sampling theory can be based on mass transfer coefficients or rate constants. Generally, these models have not been inter-related. Starting with basic models, the exchange of chemicals between the gaseous phase and the sampler is developed using mass transfer coefficients and rate constants. Importantly, the inter-relationships between the approaches are demonstrated by relating uptake rate constants and loss rate constants to mass transfer coefficients when either sampler-side or air-side resistance is dominating chemical exchange. The influence of sampler area and sampler volume on chemical exchange is discussed in general terms and as they relate to frequently used parameters such as sampling rates and time to equilibrium. Where air-side or sampler-side resistance dominates, an increase in the surface area of the sampler will increase sampling rates. Sampling rates are not related to the sampler/air partition coefficient (K(SV)) when air-side resistance dominates and increase with K(SV) when sampler-side resistance dominates.

Air Pollutants↗

PubMed2004

Potential contamination of shipboard air samples by diffusive emissions of PCBs and other organic pollutants: implications and solutions.

Air samples were taken onboard the RRS Bransfield on an Atlantic cruise from the United Kingdom to Halley, Antarctica, from October to December 1998, with the aim of establishing PCB oceanic background air concentrations and assessing their latitudinal distribution. Great care was taken to minimize pre- and post-collection contamination of the samples, which was validated through stringent QA/QC procedures. However, there is evidence that onboard contamination of the air samples occurred,following insidious, diffusive emissions on the ship. Other data (for PCBs and other persistent organic pollutants (POPs)) and examples of shipboard contamination are presented. The implications of these findings for past and future studies of global POPs distribution are discussed. Recommendations are made to help critically appraise and minimize the problems of insidious/diffusive shipboard contamination.

Air↗

PubMed2004

Evidence for dynamic air-water coupling and cycling of persistent organic pollutants over the open Atlantic Ocean.

Ship-board air samples collected between The Netherlands and South Africa in January-February 2001 were analyzed for PCBs and selected organochlorine compounds. Broad latitudinal trends in compound concentrations were influenced by proximity to source areas, land, and air mass origin. Lowest concentrations were observed in the remote south Atlantic (1-32 degrees S), where sigma7PCB concentrations were approximately 10 pg m(-3). Here, a diurnal cycle was noted for some PCB congeners, with the daytime concentrations higher than the nighttime concentrations, typically by a factor of 1.5-2.5. The data are consistent with a close coupling of air-open ocean concentrations, which has important implications for future rates of POP removal from the global "recyclable pool". The observations are discussed in the context of the potential controlling variables. Interactions between the phytoplankton and the dissolved phase are implicated in controlling the observations made here and a hypothesis to explain the cycling trends is presented. However, the precise mechanisms remain unclear; further studies are urgently required to elucidate them.

Air Pollutants↗

PubMed2004

Assessment of bioavailable PAH, PCB and OCP concentrations in water, using semipermeable membrane devices (SPMDs), sediments and caged carp.

Bioavailable water concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed at several freshwater sites in and around the city of Amsterdam. Carp (Cyprinus carpio) were caged for 4 weeks at 10 sites, together with semipermeable membrane devices (SPMDs). In addition, sediment samples were taken at each site. SPMDs and sediments were analysed for PAHs, PCBs and OCPs. Carp muscle tissues were analysed for PCBs and OCP, while PAH metabolites were assessed in fish bile. Contaminant concentrations in the water phase were estimated using three different methods: 1. Using fish tissue concentrations and literature bioconcentration factors (BCFs), 2. Using SPMD levels and a kinetic SPMD uptake model, and 3. Using sediment levels and literature sorption coefficients (K(oc)s). Since PAH accumulation in fish is not considered an accurate indicator of PAH exposure, calculated aqueous PAH concentrations from SPMD data were compared with semiquantitatively determined biliary PAH metabolite levels. Contaminant concentrations in the water phase estimated with fish data (Cw(fish)) and SPMD data (Cw(spmd)) were more in line for compounds with lower K(ow) than for compounds with higher K(ow) values. This indicates that the assumption of fish-water sorption equilibrium was not valid. At most sites, sediment-based water levels (Cw(sed)) were comparable with the Cw(spmd), although large differences were observed at certain sites. A significant correlation was observed between biliary PAH metabolite levels in fish and aqueous PAH concentrations estimated with SPMD data, suggesting that both methods may be accurate indicators of PAH exposure in aquatic ecosystems.

Animals↗

PubMed2004

Spatial distribution of atmospheric PAHs and PCNs along a north-south Atlantic transect.

Ship-board air samples collected between The Netherlands and South Africa in January-February 2001 were analysed for polycyclic aromatic hydrocarbons (PAHs) and polychlorinated naphthalenes (PCNs). The highest PAH concentrations occurred in the European samples, and in samples close to West Africa and South Africa. Consistently low PAH concentrations were measured in the southern hemisphere open ocean samples (190-680 pg/m3). The highest PCN concentrations occurred in the European samples, but high values were also detected off the West African coast, and in the sample taken closest to South Africa. Data are presented for diurnal cycles taken in the remote South Atlantic. The day:night ratios of phenanthrene, 1-methylphenanthrene and fluoranthene were typically approximately 1.5-2.5:1. The mechanism(s) causing this observation is/are not understood at present, but dynamic environmental process(es) is/are implicated.

Air Pollutants↗

PubMed2003

Dissolved PCBs, PAHs, and HCB in pore waters and overlying waters of contaminated harbor sediments.

Aqueous concentrations of polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), pentachlorobenzene, and hexachlorobenzene (HCB) were determined by exposing low-density polyethylene (LDPE) strips to the pore waters and the overlying water in two contaminated harbors. LDPE strips were also exposed in the laboratory to sediment slurries and to stagnant sediments collected at the same locations. Surprisingly short equilibration time scales (1-60 days for log K(ow) < 7) were observed for the exposures to sediment slurries. This was a result of a profound decrease in transport resistance, due to the presence of particles in the aqueous boundary layer. Concentrations in the pore water were calculated from the initial uptake rates and the dissipation rates of performance reference compounds. Good correspondence existed with concentrations estimated from the equilibrium amounts in the strips and LDPE-water partition coefficients. Sediment-water partition coefficients for PAHs were higher than for PCBs and chlorobenzenes by approximately 1 order of magnitude. A one-dimensional diffusion model was used to describe contaminant uptake by LDPE strips from stagnant sediments. The results indicated that 95% of the PAHs and 50% of the PCBs were immobile on a time scale of two months. A comparison of concentrations in pore waters and water columns indicated that a fair degree of equilibrium existed for PCBs and that one sediment was a potential source of PAHs. Concentrations of HCB near a former discharge site were higher by a factor of 6 compared to reference locations.

Biological Availability↗

PubMed2003

Levels of polybrominated diphenyl ether flame retardants in sediment cores from Western Europe.

The levels of 14 brominated diphenyl ether (BDE)-congeners in sediment cores from three locations in Western Europe have been determined by GC/MS (negative chemical ionization mode). Sediments from the Drammenfjord (Norway), the western Wadden Sea (The Netherlands), and the freshwater Lake Woserin (Mecklenburg-Vorpommern, Germany) showed a time-dependent pattern in the distribution of BDEs since the beginning of the industrial production of polybrominated diphenyl ether (PBDE) formulations. Two out of three commercially available PBDE formulations could be distinguished. Starting from the beginning of the 1970s, the penta-mix formulation is clearly present, but the deca-mix formulation is only present since the late 1970s. The octa-mix formulation appeared to be still absent in these sediments, as its marker-congener, BDE183, was never detected. In the cores from the western Wadden Sea and Lake Woserin, all TOC-normalized concentrations of the penta-BDE-derived congeners were leveling off in the most recent sediment layers representing 1995 and 1997, whereas those in the Drammenfjord were still increasing in 1999. The levels of BDE209, however, decreased in the most recent layer of all three cores. In Lake Woserin, the concentrations of BDE209 were much less elevated above those of the tri- to hexa-BDEs than in the other the two areas. This might be due to the absence of a significant PBDE input from sources other than the atmosphere to this rural lake. The absence of all PBDE congeners in the older layers of the three sediment cores, as well as in several 100-150-My-old layers from an extremely organic-rich marine sediment from the Kimmeridge clay formation in Dorset (UK), indicated the absence of natural production of the BDE congeners analyzed.

Environmental Monitoring↗

PubMed2003

Temperature-dependent uptake rates of nonpolar organic compounds by semipermeable membrane devices and low-density polyethylene membranes.

The effect of temperature on sampling rates and sampler-water partition coefficients of semipermeable membrane devices (SPMDs) and low-density polyethylene (LDPE) strips was studied in an experimental setup under controlled flow conditions. Aqueous concentrations of chlorobenzenes, polychlorinated biphenyls (PCBs), and polyaromatic hydrocarbons (PAHs) were maintained by continuous circulation of the water over a generator column. Sampling rates for standard design SPMDs (460 cm2) were in the range of 20-200 L d(-1). No significant differences were observed between sampling rates of SPMDs and LDPE strips, but the latter samplers reached equilibrium faster because of their smaller sorption capacity. Sampling rates at 30 degrees C were higher than at 2 degrees C by a factor of about 3. Sampling rate modeling indicated boundary layer-controlled uptake for compounds with log octanol-water partition coefficients smaller than 4.4 and aqueous boundary-layer controlled uptake for more hydrophobic compounds. SPMD-water partition coefficients did not significantly change with temperature, but LDPE-water partition coefficients were larger at 2 degrees C than at 30 degrees C by a factor of 2. For field application of SPMDs, the results imply that temperature is not a key factor that controls uptake rates unless large geographical and temporal scales are involved. The results confirm that water flow velocity has a profound effect on sampling rates.

Environmental Monitoring↗

PubMed2002

Development of the permeability/performance reference compound approach for in situ calibration of semipermeable membrane devices.

Permeability/performance reference compounds (PRCs) are analytically noninterfering organic compounds with moderate to high fugacity from semipermeable membrane devices (SPMDs) that are added to the lipid prior to membrane enclosure. Assuming that isotropic exchange kinetics (IEK) apply and that SPMD-water partition coefficients are known, measurement of PRC dissipation rate constants during SPMD field exposures and laboratory calibration studies permits the calculation of an exposure adjustment factor (EAF). In theory, PRC-derived EAF ratios reflect changes in SPMD sampling rates (relative to laboratory data) due to differences in exposure temperature, membrane biofouling, and flow velocity-turbulence at the membrane surface. Thus, the PRC approach should allow for more accurate estimates of target solute/vapor concentrations in an exposure medium. Undersome exposure conditions, the impact of environmental variables on SPMD sampling rates may approach an order of magnitude. The results of this study suggest that most of the effects of temperature, facial velocity-turbulence, and biofouling on the uptake rates of analytes with a wide range of hydrophobicities can be deduced from PRCs with a much narrower range of hydrophobicities. Finally, our findings indicate that the use of PRCs permits prediction of in situ SPMD sampling rates within 2-fold of directly measured values.

Calibration↗

PubMed2002

Spiking of performance reference compounds in low density polyethylene and silicone passive water samplers.

A method for spiking performance reference compounds (PRCs) into low density polyethylene (LDPE) and silicone polymers is described. This method is based on equilibration of the polymers in aqueous/methanolic solutions of PRCs. Equilibration times range from minutes to hours for perdeuterated polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) with a hydrophobicity in the range 3.9 < logKow < 7.7. Best results were obtained for methanol-water ratios of 80/20 (v/v). The method allows for the use of PRCs for in situ calibration of the uptake kinetics of these solvent-free sampling phases in a similar way as for semipermeable membrane devices (SPMDs).

Calibration↗

PubMed2002

Levels of some polybrominated diphenyl ether (PBDE) flame retardants along the Dutch coast as derived from their accumulation in SPMDs and blue mussels (Mytilus edulis).

Aqueous concentrations of individual brominated diphenyl ethers (BDEs) were determined for five stations in the Scheldt estuary and the North Sea along the Dutch coast using passive sampling by semipermeable membrane devices (SPMDs). Values of 0.1-5 pg l(-1) were observed. The highest levels were found in the Scheldt estuary. Concentration differences between February and October were a factor of 4-8 for BDE209, and were smaller than a factor of 2 for the other BDEs. Bioaccumulation was studied for native mussels and for mussels that were transplanted from an uncontaminated area into the Scheldt estuary for 6 weeks. Concentrations in native mussels were higher by a factor of 10 and 2 for BDEs and PCBs, respectively. Field based bioaccumulation factors (BAFs) were higher for BDEs than for PCBs by a factor of 10. Depuration experiments showed that the larger part of the BDE209 content in mussels was associated with ingested particles, whereas no such effect was observed for the other BDEs or PCBs.

Animals↗