Publications by authors named "Frederic Been"

31 Publications

What's in the water? - Target and suspect screening of contaminants of emerging concern in raw water and drinking water from Europe and Asia.

Water Res 2021 Apr 1;198:117099. Epub 2021 Apr 1.

Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE-750 07 Uppsala, Sweden.

There is growing worry that drinking water can be affected by contaminants of emerging concern (CECs), potentially threatening human health. In this study, a wide range of CECs (n = 177), including pharmaceuticals, pesticides, perfluoroalkyl substances (PFASs) and other compounds, were analysed in raw water and in drinking water collected from drinking water treatment plants (DWTPs) in Europe and Asia (n = 13). The impact of human activities was reflected in large numbers of compounds detected (n = 115) and high variation in concentrations in the raw water (range 15-7995 ng L for ∑CECs). The variation was less pronounced in drinking water, with total concentration ranging from 35 to 919 ng L. Treatment efficiency was on average 65 ± 28%, with wide variation between different DWTPs. The DWTP with the highest ∑CEC concentrations in raw water had the most efficient treatment procedure (average treatment efficiency 89%), whereas the DWTP with the lowest ∑CEC concentration in the raw water had the lowest average treatment efficiency (2.3%). Suspect screening was performed for 500 compounds ranked high as chemicals of concern for drinking water, using a prioritisation tool (SusTool). Overall, 208 features of interest were discovered and three were confirmed with reference standards. There was co-variation between removal efficiency in DWTPs for the target compounds and the suspected features detected using suspect screening, implying that removal of known contaminants can be used to predict overall removal of potential CECs for drinking water production. Our results can be of high value for DWTPs around the globe in their planning for future treatment strategies to meet the increasing concern about human exposure to unknown CECs present in their drinking water.
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http://dx.doi.org/10.1016/j.watres.2021.117099DOI Listing
April 2021

Changes in drug use in European cities during early COVID-19 lockdowns - A snapshot from wastewater analysis.

Environ Int 2021 Mar 26;153:106540. Epub 2021 Mar 26.

Environmental and Public Health Analytical Chemistry, Research Institute for Pesticides and Water, University Jaume I, Castellón, Spain; Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, the Netherlands. Electronic address:

The COVID-19 outbreak has forced countries to introduce severe restrictive measures to contain its spread. In particular, physical distancing and restriction of movement have had important consequences on human behaviour and potentially also on illicit drug use and supply. These changes can be associated with additional risks for users, in particular due to reduced access to prevention and harm reduction activities. Furthermore, there have been limitations in the amount of data about drug use which can be collected due to restrictions. To goal of this study was to obtain information about potential changes in illicit drug use impacted by COVID-19 restrictions. Wastewater samples were collected in seven cities in the Netherlands, Belgium, Spain and Italy at the beginning of lockdowns (March-May 2020). Using previously established and validated methods, levels of amphetamine (AMP), methamphetamine (METH), MDMA, benzoylecgonine (BE, the main metabolite of cocaine) and 11-nor-9-carboxy-Δ-tetrahydrocannabinol (THC-COOH, main metabolite of tetrahydrocannabinol (THC)) were measured and compared with findings from previous years. Important differences in levels of consumed drugs were observed across the considered countries. Whilst for some substances and locations, marked decreases in consumption could be observed (e.g., 50% decrease in MDMA levels compared to previous years). In some cases, similar or even higher levels compared to previous years could be found. Changes in weekly patterns were also observed, however these were not clearly defined for all locations and/or substances. Findings confirm that the current situation is highly heterogeneous and that it remains very difficult to explain and/or predict the effect that the present pandemic has on illicit drug use and availability. However, given the current difficulty in obtaining data due to restrictions, wastewater analysis can provide relevant information about the situation at the local level, which would be hard to obtain otherwise.
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http://dx.doi.org/10.1016/j.envint.2021.106540DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7997602PMC
March 2021

Online Prioritization of Toxic Compounds in Water Samples through Intelligent HRMS Data Acquisition.

Anal Chem 2021 03 16;93(12):5071-5080. Epub 2021 Mar 16.

KWR Water Research Institute, P.O. Box 1072, 3430 BB Nieuwegein, The Netherlands.

LC-HRMS-based nontarget screening (NTS) has become the method of choice to monitor organic micropollutants (OMPs) in drinking water and its sources. OMPs are identified by matching experimental fragmentation (MS2) spectra with library or -predicted spectra. This requires informative experimental spectra and prioritization to reduce feature numbers, currently performed post data acquisition. Here, we propose a different prioritization strategy to ensure high-quality MS2 spectra for OMPs that pose an environmental or human health risk. This online prioritization triggers MS2 events based on detection of suspect list entries or isotopic patterns in the full scan or an additional MS2 event based on fragment ion(s)/patterns detected in a first MS2 spectrum. Triggers were determined using cheminformatics; potentially toxic compounds were selected based on the presence of structural alerts, -fragmented, and recurring fragments and mass shifts characteristic for a given structural alert identified. After MS acquisition parameter optimization, performance of the online prioritization was experimentally examined. Triggered methods led to increased percentages of MS2 spectra and additional MS2 spectra for compounds with a structural alert. Application to surface water samples resulted in additional MS2 spectra of potentially toxic compounds, facilitating more confident identification and emphasizing the method's potential to improve monitoring studies.
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http://dx.doi.org/10.1021/acs.analchem.0c04473DOI Listing
March 2021

Application of wastewater-based epidemiology to investigate stimulant drug, alcohol and tobacco use in Lithuanian communities.

Sci Total Environ 2021 Feb 19;777:145914. Epub 2021 Feb 19.

Toxicological Centre, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium. Electronic address:

WBE was applied to evaluate illicit drug (i.e. amphetamine, cocaine, MDMA and methamphetamine), alcohol and tobacco use in three Lithuanian cities in 2018 and 2019. Considerable concentrations of methamphetamine and MDMA were found in the three locations, suggesting a specific Lithuanian consumption pattern. Yet, unexpected high concentrations of amphetamine (>4 μg/L) were detected in two samples of Kaunas in 2018. Through the use of chiral analysis and non-target and suspect drug precursor compound screening, these extreme values were confirmed to be the result of direct disposal of amphetamine in the sewers. Furthermore, substantial alcohol use was measured in the three investigated catchment populations of Lithuania with almost 4 standard drinks/day/inhabitant aged 15+ on average in 2019. For tobacco, an average of 5.6 cigarettes/day/inhabitant aged 15+ in 2019 was reported with large discrepancies between WBE figures and sales data, potentially highlighting illegal trade of tobacco products.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145914DOI Listing
February 2021

International snapshot of new psychoactive substance use: Case study of eight countries over the 2019/2020 new year period.

Water Res 2021 Apr 3;193:116891. Epub 2021 Feb 3.

Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide 5001, South Australia, Australia. Electronic address:

There is considerable concern around the use of new psychoactive substances (NPS), but still little is known about how much they are really consumed. Analysis by forensics laboratories of seized drugs and post-mortem samples as well as hospital emergency rooms are the first line of identifying both 'new' NPS and those that are most dangerous to the community. However, NPS are not necessarily all seized by law enforcement agencies and only substances that contribute to fatalities or serious afflictions are recorded in post-mortem and emergency room samples. To gain a better insight into which NPS are most prevalent within a community, complementary data sources are required. In this work, influent wastewater was analysed from 14 sites in eight countries for a variety of NPS. All samples were collected over the 2019/2020 New Year period, a time which is characterized by celebrations and parties and therefore a time when more NPS may be consumed. Samples were extracted in the country of origin following a validated protocol and shipped to Australia for final analysis using two different mass spectrometric strategies. In total, more than 200 were monitored of which 16 substances were found, with geographical differences seen. This case study is the most comprehensive wastewater analysis study ever carried out for the identification of NPS and provides a starting point for future, ongoing monitoring of these substances.
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http://dx.doi.org/10.1016/j.watres.2021.116891DOI Listing
April 2021

Development of a framework to derive effect-based trigger values to interpret CALUX data for drinking water quality.

Water Res 2021 Apr 21;193:116859. Epub 2021 Jan 21.

KWR Water Research Institute, Groningenhaven 7, 3433BB Nieuwegein, Netherlands; Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.

Bioassays are increasingly being implemented for water quality monitoring as targeted chemical analyses are not always sufficient for the detection of all emerging chemicals or transformation products. However, the interpretation of bioassay results remains challenging, in particular because a positive response does not necessarily indicate that there may be an increased risk. For this purpose, effect-based trigger (EBT) values have been introduced as thresholds above which action needs to be undertaken to determine the cause of the response. The goals of this study were to (i) evaluate various approaches used to determine EBT values and (ii) based on the findings, derive human health EBT values for Chemical Activated LUciferase gene eXpression (CALUX) in vitro bioassays used for routine monitoring of water quality in the Netherlands. Finally, (iii) an uncertainty analysis was carried out to determine the protective power of the derived EBT values and the chance that potentially harmful substances might not be detected. EBT values that can be implemented in routine monitoring could be determined for four of eight selected bioassays. These EBT were compared to bioassay results from routine water quality monitoring carried out in the Netherlands. Furthermore, a framework for the calculation and evaluation of derived EBT values for routine application to monitor drinking water and its sources is proposed.
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http://dx.doi.org/10.1016/j.watres.2021.116859DOI Listing
April 2021

Implementation of environmental surveillance for SARS-CoV-2 virus to support public health decisions: Opportunities and challenges.

Curr Opin Environ Sci Health 2020 Oct 1;17:49-71. Epub 2020 Oct 1.

Water & Health Pty Ltd, North Sydney, 2060, Australia.

Analysing wastewater can be used to track infectious disease agents that are shed via stool and urine. Sewage surveillance of SARS-CoV-2 has been suggested as a tool to determine the extent of COVID-19 in cities and serve as an early warning for (re-)emergence of SARS-CoV-2 circulation in communities. The focus of this review is on the strength of evidence, opportunities and challenges for the application of sewage surveillance to inform public health decision making. Considerations for undertaking sampling programs are reviewed including sampling sites, strategies, sample transport, storage and quantification methods; together with the approach and evidence base for quantifying prevalence of infection from measured wastewater concentration. Published SARS-CoV-2 sewage surveillance studies (11 peer reviewed and 10 preprints) were reviewed to demonstrate the current status of implementation to support public health decisions. Although being very promising, a number of areas were identified requiring additional research to further strengthen this approach and take full advantage of its potential. In particular, design of adequate sampling strategies, spatial and temporal resolution of sampling, sample storage, replicate sampling and analysis, controls for the molecular methods used for the quantification of SARS-CoV-2 RNA in wastewater. The use of appropriate prevalence data and methods to correlate or even translate SARS-CoV-2 concentrations in wastewater to prevalence of virus shedders in the population is discussed.
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http://dx.doi.org/10.1016/j.coesh.2020.09.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7528975PMC
October 2020

Testing wastewater from a music festival in Switzerland to assess illicit drug use.

Forensic Sci Int 2020 Apr 15;309:110148. Epub 2020 Jan 15.

École des Sciences Criminelles, University of Lausanne, 1015, Lausanne, Switzerland.

This article describes the application of a recently proposed framework for deploying wastewater-based epidemiology (WBE) to monitor illicit drug use within festivals (Benaglia et al., 2019). The festival under study was a week-long music festival in Switzerland (Swiss Festival) which attracted around 50,000 people daily. Wastewater sampling was performed during its 2014 and 2015 editions. As the Swiss Festival's wastewater is conveyed to the sewage treatment plant (STP) of the nearby city, to assess illicit drug use when there is no festival (i.e. the background consumption) wastewater sampling was also carried out during an off-festival week in 2015. During the 2014 and 2015 editions of the Swiss Festival, WBE highlighted that the most consumed illicit drugs were cannabis, MDMA, cocaine and amphetamine. Excluding cannabis, the means per capita loads of all illicit drugs were not statistically different between both editions of the Swiss Festival. The results were then compared to those of an Australian festival which had also been subject of a quantitatively assessed illicit drug use study (Lai et al., 2013). This comparison confirmed that MDMA is highly prevalent, as well as amphetamine, although to a lesser extent. Consumption of cocaine (in Switzerland) and methamphetamine (in Australia) is also high, but their use seems to be related to their availability (i.e. to the country where the festival takes place). Furthermore, it was observed that MDMA and amphetamine are more consumed during the festival compared to normal times, when there is no festival. This might suggest that their availability is increased and therefore, that a market for these substances potentially exists during the festival. This last hypothesis was assessed by consulting drug seizures made by the police during the 2015 Swiss Festival. Despite very limited data, police records suggested that most of the drugs were purchased at the festival, which supports the previous hypothesis. Results validate, on the one hand, WBE as a useful indicator to monitor illicit drug use within festivals and on the other hand, the suggested framework for deploying WBE in such environment. In addition, this study suggests the need for prevention and harm reduction measures targeted on MDMA and amphetamine during the Swiss Festival, such as drug checking laboratories.
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http://dx.doi.org/10.1016/j.forsciint.2020.110148DOI Listing
April 2020

Spatio-temporal assessment of illicit drug use at large scale: evidence from 7 years of international wastewater monitoring.

Addiction 2020 01 23;115(1):109-120. Epub 2019 Oct 23.

Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Zatisi, Czech Republic.

Background And Aims: Wastewater-based epidemiology is an additional indicator of drug use that is gaining reliability to complement the current established panel of indicators. The aims of this study were to: (i) assess spatial and temporal trends of population-normalized mass loads of benzoylecgonine, amphetamine, methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) in raw wastewater over 7 years (2011-17); (ii) address overall drug use by estimating the average number of combined doses consumed per day in each city; and (iii) compare these with existing prevalence and seizure data.

Design: Analysis of daily raw wastewater composite samples collected over 1 week per year from 2011 to 2017.

Setting And Participants: Catchment areas of 143 wastewater treatment plants in 120 cities in 37 countries.

Measurements: Parent substances (amphetamine, methamphetamine and MDMA) and the metabolites of cocaine (benzoylecgonine) and of Δ -tetrahydrocannabinol (11-nor-9-carboxy-Δ -tetrahydrocannabinol) were measured in wastewater using liquid chromatography-tandem mass spectrometry. Daily mass loads (mg/day) were normalized to catchment population (mg/1000 people/day) and converted to the number of combined doses consumed per day. Spatial differences were assessed world-wide, and temporal trends were discerned at European level by comparing 2011-13 drug loads versus 2014-17 loads.

Findings: Benzoylecgonine was the stimulant metabolite detected at higher loads in southern and western Europe, and amphetamine, MDMA and methamphetamine in East and North-Central Europe. In other continents, methamphetamine showed the highest levels in the United States and Australia and benzoylecgonine in South America. During the reporting period, benzoylecgonine loads increased in general across Europe, amphetamine and methamphetamine levels fluctuated and MDMA underwent an intermittent upsurge.

Conclusions: The analysis of wastewater to quantify drug loads provides near real-time drug use estimates that globally correspond to prevalence and seizure data.
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http://dx.doi.org/10.1111/add.14767DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6973045PMC
January 2020

The use of wastewater analysis in forensic intelligence: drug consumption comparison between Sydney and different European cities.

Forensic Sci Res 2019 17;4(2):141-151. Epub 2019 Jan 17.

Centre for Forensic Science, University of Technology Sydney, Broadway, NSW, Australia.

Wastewater analysis offers objective and complementary information to illicit drug agencies by monitoring patterns of illicit drug consumption. In this study, wastewater samples from three different wastewater treatment plants in Sydney, Australia were collected in March 2016. Ten targeted drugs were analysed and temporal and geographical analyses were performed to obtain a better understanding of the type and amount of illicit drugs consumed in Sydney in comparison with similar studies conducted around Australia and in Europe. Among the targeted drugs, methamphetamine was consumed the most, followed by cocaine and 3,4-methylenedioxymethamphetamine (MDMA). Weekly patterns were observed where a peak during the weekend was present. The geographical analysis showed differences between the regions targeted. This observation may be related to socio-demographic aspects. The comparison of our study to other data sources from Australia showed a high consumption of methamphetamine in Sydney and Western Australia. The comparison between Sydney and different European cities revealed a difference in consumption, which is in line with traditional market indicators. The information obtained through wastewater analysis provides complementary information regarding illicit drug consumption, the size, and the evolution of the illicit drug market. This, ultimately, will assist authorities in making informed decisions.
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http://dx.doi.org/10.1080/20961790.2018.1500082DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6610511PMC
January 2019

Metabolites of phosphate flame retardants and alternative plasticizers in urine from intensive care patients.

Chemosphere 2019 Oct 4;233:590-596. Epub 2019 Jun 4.

Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium. Electronic address:

Several regulatory offices called for the phase-out of di (2-ethylhexyl) phthalate (DEHP) in medical devices if safer alternatives are available. In medical devices, the occurrence of alternative plasticizers (APs) is widely variable among types of devices. However, plasticizer use is constantly evolving, as there is no reference to guide manufacturers in the choice and amount to be integrated into their products. As intensive care unit (ICU) patients need numerous indwelling plastic devices during their treatment, we hypothesized that these patients are exposed to APs and phosphate flame retardants and plasticizers (PFRs). Urinary metabolites of APs and PFRs were analyzed in the urine of adult ICU patients (n = 24) over a time period of four days. Our results show that adult ICU patients are exposed to PFRs as well as to APs concentrations were much lower compared to the levels of DEHP metabolites in the same samples. However, significantly higher than in controls (n = 15) this exposure resulted in detectable urinary levels in almost every patient and at every studied time point. Increasing temporal trends were observed for several metabolites from admission until day 3 at ICU. The use of specific medical devices, such as continuous venovenous hemofiltration (CVVH) and extracorporeal membrane oxygenation (ECMO), was associated with an increase in urinary concentrations for several PFR metabolites, despite the lack of information on the presence of these plasticizer chemicals in such medical devices. Further research into the possibly toxic effects of these chemicals released from medical devices is urgently needed.
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http://dx.doi.org/10.1016/j.chemosphere.2019.05.280DOI Listing
October 2019

Development and validation of a bioanalytical assay based on liquid chromatography-tandem mass spectrometry for measuring biomarkers of exposure of alternative plasticizers in human urine and serum.

Talanta 2019 Jun 5;198:230-236. Epub 2019 Feb 5.

Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, 2610 Wilrijk, Belgium. Electronic address:

Alternative plasticizers (APs) have been increasingly used in the last decade to replace conventional phthalate esters, in particular di(2-ethylhexyl) phthalate (DEHP), due to the toxicity of the latter. However, there is currently very little data about the toxicity of and exposure to APs. No method exists so far for the analysis of multiple exposure biomarkers. The objective of this work consisted in developing a simple bioanalytical procedure for the analysis of multiple exposure biomarkers of APs in human urine and serum. Focus was set on metabolites of di(2-propylheptyl) phthalate (DPrHpP), di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHTP) and di-2-ethylhexyl adipate (DEHA). A sample preparation protocol was developed and optimized using Oasis HLB solid-phase extraction (SPE) cartridges. Subsequently, an instrumental method based on liquid-chromatography coupled to tandem mass spectrometry (LC-MS/MS) was optimized. Following established guidelines, the sample preparation and instrumental methods were validated in terms of recovery, matrix effects, carry-over, linearity, limits of quantification, within- and between-run precision and trueness. Obtained results were satisfactory for all compounds except for one of the metabolites of DEHA (i.e., mono(2-ethylhexyl) adipate (MEHA)). A pilot biomonitoring study was carried out to assess the method's ability to detect and quantify target analytes in human urine and serum. In urine, most analytes could be detected with frequencies ranging from 8% for mono(2-ethyl-5-hydroxyhexyl) adipate (OH-MEHA) and cyclohexane-1,2-dicarboxylic mono hydroxyisononyl ester (OH-MINCH) to 92% for mono(2-ethyl-5-oxohexyl) adipate (oxo-MEHA), whilst most compounds could not be detected in serum, except for mono(2-ethylhexyl) terephthalate (MEHTP) and mono-(2-propyl-6-hydroxyheptyl) phthalate (OH-MPrHpP) which were detected in all samples. The obtained results show that the developed method can be used to simultaneously analyse multiple exposure biomarkers to APs in human urine and serum.
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http://dx.doi.org/10.1016/j.talanta.2019.02.024DOI Listing
June 2019

Hair as an alternative matrix to monitor human exposure to plasticizers - Development of a liquid chromatography - tandem mass spectrometry method.

J Chromatogr B Analyt Technol Biomed Life Sci 2019 Jan 2;1104:94-101. Epub 2018 Oct 2.

Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, 2610 Wilrijk, Belgium. Electronic address:

The application and production of alternative plasticizers (APs) has been increasing in the last decade in replacement of conventional phthalates due to their toxicity. This calls for the development of non-invasive monitoring approaches to assess human exposure to APs. A method for the simultaneous measurement of exposure biomarkers of di(2‑propylheptyl) phthalate (DPHP), di(isononyl)cyclohexane‑1,2‑dicarboxylate (DINCH), di(2‑ethylhexyl) terephthalate (DEHTP) and di‑2‑ethylhexyl adipate (DEHA) in hair samples was developed and validated in this study. Prior to the analysis, the hair samples were washed in acetone and ultrapure water and pulverized to powder. Further, a solid-liquid and solid-phase extraction, followed by quantification using liquid chromatography - tandem mass spectrometry (LC-MS/MS) was performed. The method was validated in terms of recovery, matrix effects, carry-over, linearity, limits of quantification, within- and between-run precision and trueness. Satisfying results were obtained for all targeted compounds, except for mono(2‑ethylhexyl) adipate (MEHA), which was monitored only qualitatively. The optimized method was implemented in a pilot biomonitoring study with hair samples from 9 healthy volunteers. Detection frequencies of seven metabolites ranged from 11% to 100%. Mono(2‑ethylhexyl) terephthalate (MEHTP) and mono(2‑ethyl‑5‑oxohexyl) adipate (oxo-MEHA) were found in all hair samples. More hydrophobic monoester metabolites were found to be incorporated in hair to a greater extent compared to their oxidized counterparts. Obtained results show that the developed method can detect AP metabolites in hair, supporting the use of this alternative matrix in human biomonitoring.
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http://dx.doi.org/10.1016/j.jchromb.2018.09.031DOI Listing
January 2019

Simultaneous determination of 14 urinary biomarkers of exposure to organophosphate flame retardants and plasticizers by LC-MS/MS.

Anal Bioanal Chem 2018 Dec 5;410(30):7871-7880. Epub 2018 Oct 5.

Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium.

Organophosphate flame retardants and plasticizers (PFRs) are a group of chemicals widely added to consumer products. PFRs are quickly metabolized in the human body into two types of metabolites, (1) dialkyl and diaryl phosphate esters (DAPs), such as diphenyl phosphate (DPHP) and bis(1,3-dichloro-2-propyl) phosphate (BDCIPP); and (2) hydroxylated PFRs (HO-PFRs), such as 1-hydroxy-2-propyl bis(1-chloro-2-propyl) phosphate (BCIPHIPP) and 2-hydroxyethyl bis(2-butoxyethyl) phosphate (BBOEHEP). Existing analytical methods usually focus on DAPs; therefore, human biomonitoring data on HO-PFRs remain scarce. In this study, an analytical procedure was developed for the simultaneous quantification of multiple PFR metabolites in human urine, covering eight DAPs and six HO-PFRs. Sample preparation was optimized to include all target compounds using Bond-Elut C18 solid-phase extraction cartridges, followed by instrumental analysis based on liquid-chromatography coupled to tandem mass spectrometry (LC-MS/MS). Method performance was validated according to established guidelines and satisfactory results were obtained for all metabolites in terms of recovery, linearity, limits of quantification, precision, and accuracy. Recoveries ranged from 87 to 112%. Method detection limits from 0.002 ng/mL for 2-ethyl-5-hydroxyhexyl diphenyl phosphate (5-HO-EHDPHP) to 0.66 ng/mL for 4-hydroxyphenyl phenyl phosphate (4-HO-DPHP). Seven PFR metabolites were frequently detected in a small biomonitoring study (n = 14), among them bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), di-n-butyl phosphate (DNBP), 5-HO-EHDPHP, and BBOEHEP. Highest mean concentrations were found for DPHP, 2-ethylhexyl phenyl phosphate (EHPHP), and BCIPHIPP, while 4-HO-DPHP, 5-HO-EHDPHP, and EHPHP were detected in urine for the first time. Overall, the obtained results demonstrate that the developed method can be used for the simultaneous determination of 14 urinary biomarkers of exposure to PFRs. Graphical abstract ᅟ.
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http://dx.doi.org/10.1007/s00216-018-1402-2DOI Listing
December 2018

Levels of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in raw wastewater as an innovative perspective for investigating population-wide exposure to third-hand smoke.

Sci Rep 2018 09 5;8(1):13254. Epub 2018 Sep 5.

Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.

Tobacco smoking is the major cause of many chronic diseases, especially lung cancer. Knowledge about population-wide tobacco use and exposure is essential to characterise its burden on public health and evaluate policy efficacy. Obtaining such knowledge remains challenging with current methods (e.g., surveys, biomonitoring) but can be achievable with wastewater analysis, a promising tool of retrieving epidemiology information. This study examined population-wide exposure to tobacco toxicants and carcinogens through wastewater analysis and explored relationships among these chemicals. Cotinine, trans-3'-hydroxycotinine, anabasine, anatabine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) were analysed in samples from Greece, Switzerland and Belgium, where tobacco control policies are different. Measured per-capita mass loads were ranked as: nicotine biomarkers ≫ tobacco markers > carcinogens. Relationships between nicotine biomarkers and tobacco markers implied substantial use of non-tobacco nicotine items besides tobacco products. Geographic profiles of tobacco markers revealed higher levels in Geneva and Athens than Geraardsbergen and Ninove. Environmental third-hand smoke led to NNK detection, with elevated levels observed in Athens where indoor smoking is widespread, posing potential health risks to the population. Our novel outcomes are relevant for public health authorities as they provide indications about external exposure and can thus be used to plan and evaluate tobacco control policies.
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http://dx.doi.org/10.1038/s41598-018-31324-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6125383PMC
September 2018

Analysis of N,N-dimethylamphetamine in wastewater - a pyrolysis marker and synthesis impurity of methamphetamine.

Drug Test Anal 2018 Oct 20;10(10):1590-1598. Epub 2018 Jul 20.

Queensland Alliance for Environmental Health Sciences, The University of Queensland, Coopers Plains, Australia.

The increased availability of high purity crystalline methamphetamine (MA) in Australia raised concerns because of high dosages and its potential consumption through inhalation. The present work investigates the possibility of using wastewater levels of N,N-dimethylamphetamine (DMA), a pyrolysis by-product, as an indirect indicator of MA smoking. A dedicated liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QToF-MS) method was set up to detect and quantify DMA in wastewater samples. Wastewater samples were collected from 8 locations across Australia during the period 2011-2016. Data about the abundance of DMA in MA seizures as well as in residues from drug paraphernalia were obtained from forensic laboratories in Australia. DMA/MA ratios measured in wastewater ranged from 0.0001 to 0.09 (median 0.007). DMA/MA ratios in bulk seizures are generally below 0.0025, with a median value of 0.0004, whilst residues in paraphernalia ranged from 0.031 to 3.37. DMA/MA ratios in wastewater decreased between 2011 and 2016, in parallel to an increase in MA loads. Furthermore, wastewater analyses highlighted a strong positive correlation between DMA/MA ratios and per capita MA use (Pearson's correlation ρ= 0.61, p-value <0.001). Nonetheless, geographical specificities could be highlighted between the investigated locations. The obtained data could help authorities detect hot spots of drug use as well as to plan specific intervention campaigns to tackle the issue. In future, simultaneous analysis of DMA and MA in both wastewater and seizures could improve our understanding about MA use and its consumption patterns.
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http://dx.doi.org/10.1002/dta.2419DOI Listing
October 2018

Mining the Chemical Information on Urban Wastewater: Monitoring Human Exposure to Phosphorus Flame Retardants and Plasticizers.

Environ Sci Technol 2018 06 11;52(12):6996-7005. Epub 2018 Jun 11.

Toxicological Centre , University of Antwerp , Universiteitsplein 1 , 2610 Wilrijk , Belgium.

At the individual level, exposure to contaminants is generally assessed through the analysis of specific biomarkers in biological matrices. However, these studies are costly and logistically demanding, limiting their applicability to monitor population-wide exposure over time and space. By focusing on a selection of exposure biomarkers to phosphorus flame retardants and plasticizers (PFRs), this study aims to explore the possibility of using wastewater as a complementary source of information about exposure. Wastewater samples were collected from five cities in Europe and analyzed using a previously established method. Substantial differences in biomarker levels were observed between the investigated catchments, suggesting differences in exposure. Time trends in biomarkers observed between 2013 and 2016 were found to agree with results from human biomonitoring studies and reports about production volumes. Using Monte Carlo simulations, average urinary concentrations were estimated. These were generally higher compared to results from human biomonitoring studies. Various explanations for these differences were formulated (i.e., other excretion routes, external sources and different sampling approaches). Obtained results show that wastewater analysis provides unique information about geographical and temporal differences in exposure, which would be difficult to gather using other monitoring tools.
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http://dx.doi.org/10.1021/acs.est.8b01279DOI Listing
June 2018

Measuring spatial and temporal trends of nicotine and alcohol consumption in Australia using wastewater-based epidemiology.

Addiction 2018 06 26;113(6):1127-1136. Epub 2018 Feb 26.

Queensland Alliance for Environmental Health Sciences (QAEHS), formerly National Research Centre for Environmental Toxicology (Entox), The University of Queensland, Coopers Plains, QLD, Australia.

Background And Aims: Tobacco and alcohol consumption remain priority public health issues world-wide. As participation in population-based surveys has fallen, it is increasingly challenging to estimate accurately the prevalence of alcohol and tobacco use. Wastewater-based epidemiology (WBE) is an alternative approach for estimating substance use at the population level that does not rely upon survey participation. This study examined spatio-temporal patterns in nicotine (a proxy for tobacco) and alcohol consumption in the Australian population via WBE.

Methods: Daily wastewater samples (n = 164) were collected at 18 selected wastewater treatment plants across Australia, covering approximately 45% of the total population. Nicotine and alcohol metabolites in the samples were measured using liquid chromatography-tandem mass spectrometry. Daily consumption of nicotine and alcohol and its associated uncertainty were computed using Monte Carlo simulations. Nation-wide daily average and weekly consumption of these two substances were extrapolated using ordinary least squares and mixed-effect models.

Findings: Nicotine and alcohol consumption was observed in all communities. Consumption of these substances in rural towns was three to four times higher than in urban communities. The spatial consumption pattern of these substances was consistent across the monitoring periods in 2014-15. Nicotine metabolites significantly reduced by 14-25% (P = 0.001-0.008) (2014-15) in some catchments. Alcohol consumption remained constant over the studied periods. Strong weekly consumption patterns were observed for alcohol but not nicotine. Nation-wide, the daily average consumption per person (aged 15-79 years) was estimated at approximately 2.5 cigarettes and 1.3-2.0 standard drinks (weekday-weekend) of alcohol. These estimates were close to the sale figure and apparent consumption, respectively.

Conclusions: Wastewater-based epidemiology is a feasible method for objectively evaluating the geographic, temporal and weekly profiles of nicotine and alcohol consumption in different communities nationally.
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http://dx.doi.org/10.1111/add.14157DOI Listing
June 2018

Keratinous matrices for the assessment of drugs of abuse consumption: A correlation study between hair and nails.

Drug Test Anal 2018 Jan 5. Epub 2018 Jan 5.

Toxicological Centre, University of Antwerp, Belgium.

Keratinous matrices - hair and nails - accumulate substances over time and allow retrospective investigation of past consumption. Analysis of these matrices can provide information complementary to blood and urine analysis or can be used as standalone. So far, research has primarily focused on the detection of substances in hair, while studies in nails are scarce. In this study, we assessed concentrations of drugs of abuse and their metabolites in hair, fingernails, and toenails collected from the same individuals to evaluate differences and correlations between matrices. A total of 26 hair, 24 fingernail, and 18 toenail samples were collected. Samples were analysed by a validated liquid chromatography-tandem mass spectrometry method able to simultaneously detect the following compounds: amphetamine (AMP), methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyethylamphetamine, morphine (MOR), codeine (COD), 6-monoacetylmorphine (6-MAM), methadone (MTD), 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), cocaine (COC), benzoylecgonine (BE), and ecgonine methyl ester (EME). Strong positive correlations between hair, fingernails, and toenails were present for COC, BE, EME, AMP and MDMA. MOR, COD, 6-MAM, MTD and EDDP showed positive trends. Concentrations were generally higher in nails compared to hair. Ratios between parent compounds and their metabolites were assessed for 6-MAM/MOR, EDDP/MTD, BE/COC and EME/COC. Preliminary cut-off concentrations for COC, BE, EME and AMP in fingernails and toenails were proposed. In light of these results, nails can be considered as a useful alternative to hair for monitoring of long-term drug consumption. However, care should be taken regarding the variability in the accumulation of compounds between the matrices.
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http://dx.doi.org/10.1002/dta.2356DOI Listing
January 2018

Liquid Chromatography-Tandem Mass Spectrometry Analysis of Biomarkers of Exposure to Phosphorus Flame Retardants in Wastewater to Monitor Community-Wide Exposure.

Anal Chem 2017 09 7;89(18):10045-10053. Epub 2017 Sep 7.

Toxicological Centre, University of Antwerp , Universiteitsplein 1, 2610 Wilrijk, Belgium.

Phosphorus flame retardants and plasticizers (PFRs) are increasingly used in consumer goods, from which they can leach and pose potential threats to human health. Monitoring human exposure to these compounds is thus highly relevant. Current assessment of exposure through analysis of biological matrices is, however, tedious as well as logistically and financially demanding. Analysis of selected biomarkers of exposure to PFRs in wastewater could be a simple and complementary approach to monitoring, over space and time, exposure at the population level. An analytical procedure, based on solid-phase extraction (SPE) and liquid chromatography coupled to tandem mass spectrometry, was developed and validated to monitor the occurrence in wastewater of human exposure biomarkers of 2-ethylhexyldiphenyl phosphate (EHDPHP), tris(2-butoxyethyl) phosphate (TBOEP), triphenyl phosphate (TPHP), tris(2-chloroisopropyl) phosphate (TCIPP), and tris(2-chloroethyl) phosphate (TCEP). Various SPE sorbents and extraction protocols were evaluated, and for the optimized method, absolute extraction recoveries ranged between 46% and 100%. Accuracy and precision were satisfactory for the selected compounds. Method detection limits ranged from 1.6 to 19 ng L. Biomarkers of exposure to PFRs were measured for the first time in influent wastewater. Concentrations in samples collected in Belgium ranged from below the limit of quantitation to 1072 ng L, with 2-ethylhexyl phenyl phosphate (EHPHP) and TCEP being the most abundant. Per capita loads of target biomarkers varied greatly, suggesting potential differences in exposure between the investigated communities. The developed method allowed implementation of the concepts of human biomonitoring at the community scale, opening the possibility to assess population-wide exposure to PFRs.
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http://dx.doi.org/10.1021/acs.analchem.7b02705DOI Listing
September 2017

Novel Wastewater-Based Epidemiology Approach Based on Liquid Chromatography-Tandem Mass Spectrometry for Assessing Population Exposure to Tobacco-Specific Toxicants and Carcinogens.

Anal Chem 2017 09 11;89(17):9268-9278. Epub 2017 Aug 11.

Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp , Universiteitsplein 1, 2610 Antwerp, Belgium.

Tobacco smoking remains an important public health issue worldwide. Assessment of exposure to tobacco-related toxicants and carcinogens at the population level is thus an essential population health indicator. This can be achieved by wastewater-based epidemiology (WBE), which relies on the analysis of biomarkers in wastewater. However, required analytical methods for the simultaneous measurement of tobacco-related toxicants and carcinogens in wastewater are not available. In this study, a new analytical procedure was developed and validated to measure tobacco-related alkaloids, carcinogens, and their metabolites in raw wastewater, including anabasine (ANABA), anatabine (ANATA), cotinine (COT), trans-3'-hydroxycotinine (COT-OH), N-nitrosoanabasine (NAB), N-nitrosoanatabine (NAT), N-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), NNAL-N-β-glucuronide, and NNAL-O-β-glucuronide. Different parameters were optimized for the solid-phase extraction procedure and instrumental analysis using liquid chromatography-tandem mass spectrometry. The optimized method was fully validated, resulting in acceptable within-run and between-run precision (<8% and <10% relative standard deviation, respectively) and accuracy (<9% and <13% bias, respectively). Method quantification limits were at 0.5-120 ng/L in wastewater. Target analytes were stable in wastewater at 4 and 20 °C over 24 h. The developed method was applied to wastewater samples from two Belgian cities. Average concentrations of COT, COT-OH, ANATA, ANABA, and NAT were 5200, 2600, 30, 10, and 0.6 ng/L, respectively, while NAB, NNN, NNK, and NNAL were not detected in the samples. With the developed robust analytical method, our study provided the first insight into the population exposure to both toxicants and carcinogens resulting from tobacco use.
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http://dx.doi.org/10.1021/acs.analchem.7b02052DOI Listing
September 2017

Measuring biomarkers in wastewater as a new source of epidemiological information: Current state and future perspectives.

Environ Int 2017 Feb 27;99:131-150. Epub 2016 Dec 27.

Research Institute for Pesticides and Water, Universitat Jaume I, Castellon, Spain. Electronic address:

The information obtained from the chemical analysis of specific human excretion products (biomarkers) in urban wastewater can be used to estimate the exposure or consumption of the population under investigation to a defined substance. A proper biomarker can provide relevant information about lifestyle habits, health and wellbeing, but its selection is not an easy task as it should fulfil several specific requirements in order to be successfully employed. This paper aims to summarize the current knowledge related to the most relevant biomarkers used so far. In addition, some potential wastewater biomarkers that could be used for future applications were evaluated. For this purpose, representative chemical classes have been chosen and grouped in four main categories: (i) those that provide estimates of lifestyle factors and substance use, (ii) those used to estimate the exposure to toxicants present in the environment and food, (iii) those that have the potential to provide information about public health and illness and (iv) those used to estimate the population size. To facilitate the evaluation of the eligibility of a compound as a biomarker, information, when available, on stability in urine and wastewater and pharmacokinetic data (i.e. metabolism and urinary excretion profile) has been reviewed. Finally, several needs and recommendations for future research are proposed.
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http://dx.doi.org/10.1016/j.envint.2016.12.016DOI Listing
February 2017

Integrating environmental and self-report data to refine cannabis prevalence estimates in a major urban area of Switzerland.

Int J Drug Policy 2016 10 15;36:33-42. Epub 2016 Jun 15.

Ecole des Sciences Criminelles, University of Lausanne, 1015 Lausanne, Switzerland.

Background: Cannabis consumption is a topical subject because of discussions about reviewing current regulations. In this context, having a more comprehensive approach to assess and monitor prevalence and consumption is highly relevant. The objective of this work was to refine current estimates about prevalence of cannabis use by combining self-report data and results derived from wastewater analysis.

Methods: Self-report data was retrieved from surveys conducted in Switzerland and Europe. Wastewater samples were collected at the wastewater treatment plant of Lausanne, western Switzerland, over a 15 months period. The occurrence of 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH), a specific metabolite of delta-9-tetrahydrocannabinol (THC), was monitored. Bayesian hierarchical models were used to estimate consumption, prevalence and number of cannabis users in the investigated area.

Results: According to survey data, 12-months prevalence in western Switzerland was estimated to 6.2% of the population aged 15 or older, with an estimated daily cannabis consumption of 8.1gday(-1)·1000inhab(-1) (at 11.2% purity). The integrative model comprising self-report and wastewater data substantially reduced the uncertainty in the estimates and suggested a last-year prevalence of 9.4%, with a daily cannabis consumption of 14.0gday(-1)·1000inhab(-1).

Conclusion: Although in the same order of magnitude, consumption and prevalence estimates obtained with the integrative model were 78% and 52% higher compared to self-report figures, respectively. Interestingly, these figures are similar to discrepancies observed when comparing self-reported alcohol consumption and sales or tax data. The suggested integrative model allowed to account for known sources of uncertainty and provided refined estimates of cannabis prevalence in a major urban area of Switzerland.
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http://dx.doi.org/10.1016/j.drugpo.2016.06.008DOI Listing
October 2016

Profiles and changes in stimulant use in Belgium in the period of 2011-2015.

Sci Total Environ 2016 Sep 29;565:1011-1019. Epub 2016 May 29.

Toxicological Center, Department of Pharmaceutical Sciences, University of Antwerp (UA), Universiteitsplein 1, 2610 Antwerp, Belgium. Electronic address:

Adapting illicit drug policy strategies requires detailed knowledge on types and amounts of substances consumed by the target population. In this study, we applied wastewater-based epidemiology to detect spatio-temporal changes in the relative amounts of stimulants (amphetamine, methamphetamine, methylenedioxymethamphetamine (MDMA), cocaine) used in seven locations in Belgium over 2011-2015. Clear geographical differences were observed with stimulant users in large cities (Antwerp, Brussels) showing a preference for cocaine, while amphetamine use was most abundant in smaller cities (Geraardsbergen, Koksijde, Lier, Ninove, Ostend). Results obtained across õdifferent years revealed that the investigated substances had a stable share in the total amount of stimulants used, suggesting that habits of stimulant use remained constant, although differences in absolute amounts were observed across years. Investigation of the weekly pattern in stimulant use showed an increase in the use of MDMA on the weekends compared to cocaine and amphetamine.
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http://dx.doi.org/10.1016/j.scitotenv.2016.05.128DOI Listing
September 2016

Assessing geographical differences in illicit drug consumption--A comparison of results from epidemiological and wastewater data in Germany and Switzerland.

Drug Alcohol Depend 2016 Apr 6;161:189-99. Epub 2016 Feb 6.

Swiss Federal Institute of Aquatic Science and Technology (Eawag), Ueberlandstrasse 133, 8600, Dübendorf, Switzerland. Electronic address:

Background: Wastewater analysis is an innovative approach that allows monitoring illicit drug use at the community level. This study focused on investigating geographical differences in drug consumption by comparing epidemiological, crime and wastewater data.

Methods: Wastewater samples were collected in 19 cities across Germany and Switzerland during one week, covering a population of approximately 8.1 million people. Self-report data and consumption offences for the investigated areas were used for comparison and to investigate differences between the indicators.

Results: Good agreement between data sources was observed for cannabis and amphetamine-type stimulants, whereas substantial discrepancies were observed for cocaine. In Germany, an important distinction could be made between Berlin, Dortmund and Munich, where cocaine and particularly amphetamine were more prevalent, and Dresden, where methamphetamine consumption was clearly predominant. Cocaine consumption was relatively homogenous in the larger urban areas of Switzerland, although prevalence and offences data suggested a more heterogeneous picture. Conversely, marked regional differences in amphetamine and methamphetamine consumption could be highlighted.

Conclusions: Combining the available data allowed for a better understanding of the geographical differences regarding prevalence, typology and amounts of substances consumed. For cannabis and amphetamine-type stimulants, the complementarity of survey, police and wastewater data could be highlighted, although notable differences could be identified when considering more stigmatised drugs (i.e. cocaine and heroin). Understanding illicit drug consumption at the national scale remains a difficult task, yet this research illustrates the added value of combining complementary data sources to obtain a more comprehensive and accurate picture of the situation.
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http://dx.doi.org/10.1016/j.drugalcdep.2016.02.002DOI Listing
April 2016

Data triangulation in the context of opioids monitoring via wastewater analyses.

Drug Alcohol Depend 2015 Jun 2;151:203-10. Epub 2015 Apr 2.

Ecole des Sciences Criminelles, University of Lausanne, Switzerland.

Background: The need to contextualise wastewater-based figures about illicit drug consumption by comparing them with other indicators has been stressed by numerous studies. The objective of the present study was to further investigate the possibility of combining wastewater data to conventional statistics to assess the reliability of the former method and obtain a more balanced picture of illicit drug consumption in the investigated area.

Methods: Wastewater samples were collected between October 2013 and July 2014 in the metropolitan area of Lausanne (226,000 inhabitants), Switzerland. Methadone, its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), the exclusive metabolite of heroin, 6-monoacetylmorphine (6-MAM), and morphine loads were used to estimate the amounts of methadone and heroin consumed.

Results: Methadone consumption estimated from EDDP was in agreement with the expectations. Heroin estimates based on 6-MAM loads were inconsistent. Estimates obtained from morphine loads, combined to prescription/sales data, were in agreement with figures derived from syringe distribution data and general population surveys.

Conclusions: The results obtained for methadone allowed assessing the reliability of the selected sampling strategy, supporting its ability to capture the consumption of a small cohort (i.e., 743 patients). Using morphine as marker, in combination with prescription/sales data, estimates in accordance with other indicators about heroin use were obtained. Combining different sources of data allowed strengthening the results and suggested that the different indicators (i.e., administration route, average dosage and number of consumers) contribute to depict a realistic representation of the phenomenon in the investigated area. Heroin consumption was estimated to approximately 13 gd ay(-1) (118 g day(-1) at street level).
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http://dx.doi.org/10.1016/j.drugalcdep.2015.03.022DOI Listing
June 2015

Population normalization with ammonium in wastewater-based epidemiology: application to illicit drug monitoring.

Environ Sci Technol 2014 Jul 7;48(14):8162-9. Epub 2014 Jul 7.

Ecole des Sciences Criminelles, University of Lausanne , 1015 Lausanne, Switzerland.

Fluctuations in ammonium (NH4+), measured as NH4-N loads using an ion-selective electrode installed at the inlet of a sewage treatment plant, showed a distinctive pattern which was associated to weekly (i.e., commuters) and seasonal (i.e., holidays) fluctuations of the population. Moreover, population size estimates based on NH4-N loads were lower compared to census data. Diurnal profiles of benzoylecgonine (BE) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) were shown to be strongly correlated to NH4-N. Characteristic patterns, which reflect the prolonged nocturnal activity of people during the weekend, could be observed for BE, cocaine, and a major metabolite of MDMA (i.e., 4-hydroxy-3-methoxymethamphetamine). Additional 24 h composite samples were collected between February and September 2013. Per-capita loads (i.e., grams per day per 1000 inhabitants) were computed using census data and NH4-N measurements. Normalization with NH4-N did not modify the overall pattern, suggesting that the magnitude of fluctuations in the size of the population is negligible compared to those of illicit drug loads. Results show that fluctuations in the size of the population over longer periods of time or during major events can be monitored using NH4-N loads: either using raw NH4-N loads or population size estimates based on NH4-N loads, if information about site-specific NH4-N population equivalents is available.
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http://dx.doi.org/10.1021/es5008388DOI Listing
July 2014

Detection and chemical profiling of medicine counterfeits by Raman spectroscopy and chemometrics.

Anal Chim Acta 2011 Oct 5;705(1-2):334-41. Epub 2011 Aug 5.

F. Hoffmann-La Roche Ltd., Basel, Switzerland.

Raman spectroscopy combined with chemometrics has recently become a widespread technique for the analysis of pharmaceutical solid forms. The application presented in this paper is the investigation of counterfeit medicines. This increasingly serious issue involves networks that are an integral part of industrialized organized crime. Efficient analytical tools are consequently required to fight against it. Quick and reliable authentication means are needed to allow the deployment of measures from the company and the authorities. For this purpose a method in two steps has been implemented here. The first step enables the identification of pharmaceutical tablets and capsules and the detection of their counterfeits. A nonlinear classification method, the Support Vector Machines (SVM), is computed together with a correlation with the database and the detection of Active Pharmaceutical Ingredient (API) peaks in the suspect product. If a counterfeit is detected, the second step allows its chemical profiling among former counterfeits in a forensic intelligence perspective. For this second step a classification based on Principal Component Analysis (PCA) and correlation distance measurements is applied to the Raman spectra of the counterfeits.
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http://dx.doi.org/10.1016/j.aca.2011.07.043DOI Listing
October 2011