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Papers by elin eliassen

Acta Veterinaria Scandinavica, Jun 16, 2020

Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes ... more Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes of poisoning in small animal practice, but information about toxicokinetic of these rodenticides in dogs is lacking. We analysed blood and faeces from five accidentally exposed dogs and 110 healthy dogs by reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry. The aim of the study was to estimate elimination of brodifacoum, bromadiolone and difenacoum after acute exposure, calculate the half-lives of these rodenticides in dogs, estimate faecal elimination in a litter of puppies born, and further to identify the extent of AR exposure in a healthy dog population. Results: Three dogs were included after single ingestions of brodifacoum; two dogs ingested bromadiolone and one dog ingested difenacoum. Maximum concentrations in faeces were found after day 2-3 for all ARs. The distribution half-lives were 1-10 days for brodifacoum, 1-2 days for bromadiolone and 10 days for difenacoum. Brodifacoum and difenacoum had estimated terminal half-lives of 200-330 days and 190 days, respectively. In contrast, bromadiolone had an estimated terminal half-life of 30 days. No clinical signs of poisoning or coagulopathy were observed in terminal elimination period. In blood, the terminal half-life of brodifacoum was estimated to 8 days. Faeces from a litter of puppies born from one of the poisoned dogs were examined, and measurable concentrations of brodifacoum were detected in all samples for at least 28 days after parturition. A cross-sectional study of 110 healthy domestic dogs was performed to estimate ARs exposure in a dog population. Difenacoum was detected in faeces of one dog. Blood and faecal samples from the remaining dogs were negative for all ARs. Conclusions: Based on the limited pharmacokinetic data from these dogs, our results suggest that ARs have a biphasic elimination in faeces using a two-compartment elimination kinetics model. We have shown that faecal analysis is suitable and reliable for the assessment of ARs exposure in dogs and a tool for estimating the AR half-lives. Half-lives of ARs could be a valuable indicator in the exposed dogs and provides important information for veterinarians monitoring AR exposure and assessment of treatment length in dogs.

Journal of Wildlife Diseases, Oct 9, 2019

High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerou... more High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerous reports of secondary exposure through predation. Because of widespread distribution of the red fox (Vulpes vulpes), they may act as sentinels for small mammal-hunting predators in rural, suburban, and urban areas. No AR surveillance in wild mammals with analyses of residues in feces has been conducted throughout a single country. We collected 163 fecal samples from presumed healthy red foxes from 18 out of 19 counties in Norway. The foxes were shot during regular hunting between January and December 2016 and samples collected directly after death. Fecal samples were analyzed for six ARs: brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen. We detected ARs in 54% (75/139) of the animals. Brodifacoum was most frequently detected (46%; 64/139), followed by coumatetralyl (17%; 23/139), bromadiolone (16%; 22/139), difenacoum (5%; 7/139), difethialone (1%; 2/139), and flocoumafen (1%; 2/139). More than one substance was detected in 40% (30/75) of the positive foxes, and 7% (5/75) of these animals were exposed to four different ARs. There were no statistically significant seasonal, age, or sex differences in foxes after exposure to one AR compound. We found a significant difference in occurrence of brodifacoum and coumatetralyl in foxes from different geographical areas. These findings demonstrate fecal analyses as a valuable method of detecting AR exposure in red foxes. We suggest using direct fecal sampling with analyses as a method to evaluate the occurrence of ARs in live endangered wildlife in connection with radio tagging or collaring operations.

Journal of Liquid Chromatography & Related Technologies, Oct 23, 2017

ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercrit... more ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercritical fluid chromatography (UHPSFC), opening up for fast analysis and high-resolution separations. The development of new and more robust systems also makes the technique more interesting for bioanalytical analysis, where the need for reproducible and fast analysis with little downtime is great. One area where the use of UHPSFC could become a useful tool is in the separation of structural isomers of new psychoactive substances (NPS). 2-, 3-, and 4- structural isomers of fluoroamphetamine, fluoromethamphetamine, and methylmethcathinone, isomeric pairs of the synthetic cannabinoids UR-144/UR-144 degradant, XLR-11/XLR-11 degradant, JWH-015/JWH-073, and JWH-019/JWH-122, as well as amphetamine and several stable isotope-labeled amphetamine internal standards were separated with UHPSFC-MS/MS and compared with ultrahigh-pressure liquid chromatography (UHPLC) MS/MS. NPS isomers that were difficult to separate with reversed-phase UHPLC-MS/MS were separated by UHPSFC; in most cases with an orthogonal retention order to UHPLC. In contrast to the behavior seen when using reversed-phase UHPLC, the deuterated amphetamines eluted later than amphetamine with UHPSFC. 13C6-labeled amphetamine coeluted with amphetamine for all conditions, making this the best choice of an internal standard. GRAPHICAL ABSTRACT

Journal of Veterinary Diagnostic Investigation, Jun 1, 2020

Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide conc... more Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide concern, but few methods exist to determine residue levels in live animals. Traditional liver detection methods preclude determining exposure in live wildlife. To determine the value of assessing AR exposure by fecal analysis, we compared fecal and liver residues of ARs in the same animals. We collected liver and fecal samples from 40 apparently healthy red foxes (Vulpes vulpes) potentially exposed to ARs, and quantified brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen residues by liquid chromatographytandem mass spectrometry. Residues of ARs were detected in 53% of the fecal samples and 83% of the liver samples. We found good concordance between AR residues in feces and liver for coumatetralyl, difenacoum, and difethialone. Bromadiolone occurred in significantly greater frequency in livers compared to feces, but no significant difference in concentration between feces and liver in individual foxes could be detected. Brodifacoum displayed a significant difference in concentration and occurrence of positive samples between liver and feces. Our findings demonstrate that fecal analysis of ARs provides a feasible and valuable non-lethal means of determine AR exposure in live wildlife.

Journal of Chromatography B, Nov 1, 2014

An ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was... more An ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the determination of zopiclone and zolpidem in whole blood, for use in cases with suspected driving under influence of drugs (DUID) and autopsy cases. Sample preparation was performed with liquid-liquid extraction (LLE) using ethyl acetate/n-heptane (80:20, v/v) and 0.1 mL whole blood. Deuterated analogues were used as internal standards (IS) for both compounds. The compounds were separated using a reversed phase C 18-column (2.1mm x 100 mm, 1.7 µm), with a flow rate of 0.5 mL/min, 1µL injected and gradient elution with 5 mM ammonium formate pH 10.2 and acetonitrile. Quantification was done by MS/MS using multiple reaction monitoring (MRM) in positive mode. The run time of the method was 4.5 minutes including equilibration time. The calibration curves of extracted whole blood standards were fitted by linear-order calibration curves weighted 1/x, with R 2 values above 0.999 for both compounds. Intermediate precision and accuracies (bias) were 2.4-12.9% RSD and from-5.9 to 6.8%, respectively. Recoveries of the compounds were ≥ 70%. The lower limit of quantification A c c e p t e d M a n u s c r i p t 2 (LLOQ) for zopiclone was 0.50 nmol/L (0.19 ng/mL) or 0.05 pg injected on column, and 3.5 nmol/mL (1.10 ng/mL) for zolpidem, or 0.27 pg injected on column. The limit of detection (LOD) was 0.2 nmol/L (0.08 ng/mL) for zopiclone and 0.3 nmol/L (0.09 ng/mL) for zolpidem. Matrix effects (ME) were between 108-115% when calculated against IS. A comparison with former confirmation LC-MS method at the Norwegian Institute of Public Health, Division of Forensic Medicine (NIPH) was performed during method validation. Good correlation was seen for both compounds. The method has been running on a routine basis for two years, and has proven to be very robust and reliable with satisfactory long term precision and bias and with results for external quality samples corresponding well to consensus mean or median. Zopiclone and zolpidem concentrations in post mortem and ante mortem cases were reported. The method also meets the requirements of the legislative limits for driving under the influence of non-alcohol drugs introduced in the Norwegian Road Traffic Act Law from 2012.

Acta Veterinaria Scandinavica, Jan 17, 2018

Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few... more Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few reports of the elimination kinetics and half-lives in this species have been published. Our objectives were to develop and validate a new method for the quantification of anticoagulant rodenticides in canine blood and faeces using reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and apply the method on a case of anticoagulant rodenticide intoxication. Results: Sample preparation was liquid-liquid extraction. Six anticoagulant rodenticides were separated using a UPLC ® BEH C 18-column with a mobile phase consisting of 5 mM ammonium formate buffer pH 10.2 and methanol. MS/MS detection was performed with positive electrospray ionization and two multiple reaction monitoring transitions. The limits of quantification were set at the levels of the lowest calibrator (1.5-2.7 ng/mL or ng/g). The method was successfully applied to a case from a dog accidentally poisoned with anticoagulant rodenticide. Coumatetralyl and brodifacoum concentrations were determined from serial blood and faecal samples. A terminal half-life of at least 81 days for coumatetralyl in blood was estimated, which is longer than previous reported in other species. A slow elimination of brodifacoum from the faeces was found, with traces still detectable in the faeces at day 513. Conclusions: This study offers a new method of detection and quantification of six frequently used anticoagulant rodenticides in canine faeces. Such drugs might cause serious health effects and it is important to be able to detect these drugs, to initiate proper treatment. The very long elimination half-lives detected in our study is important to be aware of in assessment of anticoagulant rodenticide burden to the environment.

Journal of Liquid Chromatography & Related Technologies

ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercrit... more ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercritical fluid chromatography (UHPSFC), opening up for fast analysis and high-resolution separations. The development of new and more robust systems also makes the technique more interesting for bioanalytical analysis, where the need for reproducible and fast analysis with little downtime is great. One area where the use of UHPSFC could become a useful tool is in the separation of structural isomers of new psychoactive substances (NPS). 2-, 3-, and 4- structural isomers of fluoroamphetamine, fluoromethamphetamine, and methylmethcathinone, isomeric pairs of the synthetic cannabinoids UR-144/UR-144 degradant, XLR-11/XLR-11 degradant, JWH-015/JWH-073, and JWH-019/JWH-122, as well as amphetamine and several stable isotope-labeled amphetamine internal standards were separated with UHPSFC-MS/MS and compared with ultrahigh-pressure liquid chromatography (UHPLC) MS/MS. NPS isomers that were difficult to separate with reversed-phase UHPLC-MS/MS were separated by UHPSFC; in most cases with an orthogonal retention order to UHPLC. In contrast to the behavior seen when using reversed-phase UHPLC, the deuterated amphetamines eluted later than amphetamine with UHPSFC. 13C6-labeled amphetamine coeluted with amphetamine for all conditions, making this the best choice of an internal standard. GRAPHICAL ABSTRACT

Acta Veterinaria Scandinavica

Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes ... more Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes of poisoning in small animal practice, but information about toxicokinetic of these rodenticides in dogs is lacking. We analysed blood and faeces from five accidentally exposed dogs and 110 healthy dogs by reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry. The aim of the study was to estimate elimination of brodifacoum, bromadiolone and difenacoum after acute exposure, calculate the half-lives of these rodenticides in dogs, estimate faecal elimination in a litter of puppies born, and further to identify the extent of AR exposure in a healthy dog population. Results: Three dogs were included after single ingestions of brodifacoum; two dogs ingested bromadiolone and one dog ingested difenacoum. Maximum concentrations in faeces were found after day 2-3 for all ARs. The distribution half-lives were 1-10 days for brodifacoum, 1-2 days for bromadiolone and 10 days for difenacoum. Brodifacoum and difenacoum had estimated terminal half-lives of 200-330 days and 190 days, respectively. In contrast, bromadiolone had an estimated terminal half-life of 30 days. No clinical signs of poisoning or coagulopathy were observed in terminal elimination period. In blood, the terminal half-life of brodifacoum was estimated to 8 days. Faeces from a litter of puppies born from one of the poisoned dogs were examined, and measurable concentrations of brodifacoum were detected in all samples for at least 28 days after parturition. A cross-sectional study of 110 healthy domestic dogs was performed to estimate ARs exposure in a dog population. Difenacoum was detected in faeces of one dog. Blood and faecal samples from the remaining dogs were negative for all ARs. Conclusions: Based on the limited pharmacokinetic data from these dogs, our results suggest that ARs have a biphasic elimination in faeces using a two-compartment elimination kinetics model. We have shown that faecal analysis is suitable and reliable for the assessment of ARs exposure in dogs and a tool for estimating the AR half-lives. Half-lives of ARs could be a valuable indicator in the exposed dogs and provides important information for veterinarians monitoring AR exposure and assessment of treatment length in dogs.

Journal of Veterinary Diagnostic Investigation

Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide conc... more Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide concern, but few methods exist to determine residue levels in live animals. Traditional liver detection methods preclude determining exposure in live wildlife. To determine the value of assessing AR exposure by fecal analysis, we compared fecal and liver residues of ARs in the same animals. We collected liver and fecal samples from 40 apparently healthy red foxes ( Vulpes vulpes) potentially exposed to ARs, and quantified brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen residues by liquid chromatography–tandem mass spectrometry. Residues of ARs were detected in 53% of the fecal samples and 83% of the liver samples. We found good concordance between AR residues in feces and liver for coumatetralyl, difenacoum, and difethialone. Bromadiolone occurred in significantly greater frequency in livers compared to feces, but no significant difference in concentration...

High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerou... more High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerous reports of secondary exposure through predation. Because of widespread distribution of the red fox (Vulpes vulpes), they may act as sentinels for small mammal-hunting predators in rural, suburban, and urban areas. No AR surveillance in wild mammals with analyses of residues in feces has been conducted throughout a single country. We collected 163 fecal samples from presumed healthy red foxes from 18 out of 19 counties in Norway. The foxes were shot during regular hunting between January and December 2016 and samples collected directly after death. Fecal samples were analyzed for six ARs: brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen. We detected ARs in 54% (75/139) of the animals. Brodifacoum was most frequently detected (46%; 64/139), followed by coumatetralyl (17%; 23/139), bromadiolone (16%; 22/139), difenacoum (5%; 7/139), difethialone (1%; 2/139), and flocoumafen (1%; 2/139). More than one substance was detected in 40% (30/75) of the positive foxes, and 7% (5/75) of these animals were exposed to four different ARs. There were no statistically significant seasonal, age, or sex differences in foxes after exposure to one AR compound. We found a significant difference in occurrence of brodifacoum and coumatetralyl in foxes from different geographical areas. These findings demonstrate fecal analyses as a valuable method of detecting AR exposure in red foxes. We suggest using direct fecal sampling with analyses as a method to evaluate the occurrence of ARs in live endangered wildlife in connection with radio tagging or collaring operations.

Journal of clinical laboratory analysis, Jan 25, 2018

Phosphatidylethanols (PEths) are specific, direct alcohol biomarkers that can be determined in hu... more Phosphatidylethanols (PEths) are specific, direct alcohol biomarkers that can be determined in human blood to distinguish between heavy and social drinking. PEth 16:0/18:1 is among the most predominant PEth homologues in human blood. The aim of the study was to develop a high throughput and sensitive UHPLC-MS/MS method for the determination of PEth 16:0/18:1 in whole blood. Whole blood samples were prepared by 96-well supported liquid extraction (SLE). Extracted samples were analyzed for PEth 16:0/18:1 by reversed phase UHPLC-MS/MS. The developed UHPLC-MS/MS method was fully validated in whole blood with PEth 16:0/18:1-D as internal standard. Intermediate precision and intermediate accuracy were within ≤± 12% and ≤± 17%, respectively, at PEth 16:0/18:1 concentrations of 1.4-2112 ng/mL (2.0-3004 nmol/L). Limit of quantification (LOQ) was 1.7 ng/mL (2.4 nmol/L). For the first time, 96-well SLE was used for preparation of a PEth homologue in biological samples. A mixture of tert-butyl ...

Acta Veterinaria Scandinavica

Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few... more Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few reports of the elimination kinetics and half-lives in this species have been published. Our objectives were to develop and validate a new method for the quantification of anticoagulant rodenticides in canine blood and faeces using reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and apply the method on a case of anticoagulant rodenticide intoxication. Results: Sample preparation was liquid-liquid extraction. Six anticoagulant rodenticides were separated using a UPLC ® BEH C 18-column with a mobile phase consisting of 5 mM ammonium formate buffer pH 10.2 and methanol. MS/MS detection was performed with positive electrospray ionization and two multiple reaction monitoring transitions. The limits of quantification were set at the levels of the lowest calibrator (1.5-2.7 ng/mL or ng/g). The method was successfully applied to a case from a dog accidentally poisoned with anticoagulant rodenticide. Coumatetralyl and brodifacoum concentrations were determined from serial blood and faecal samples. A terminal half-life of at least 81 days for coumatetralyl in blood was estimated, which is longer than previous reported in other species. A slow elimination of brodifacoum from the faeces was found, with traces still detectable in the faeces at day 513. Conclusions: This study offers a new method of detection and quantification of six frequently used anticoagulant rodenticides in canine faeces. Such drugs might cause serious health effects and it is important to be able to detect these drugs, to initiate proper treatment. The very long elimination half-lives detected in our study is important to be aware of in assessment of anticoagulant rodenticide burden to the environment.

Acta Veterinaria Scandinavica, Jun 16, 2020

Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes ... more Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes of poisoning in small animal practice, but information about toxicokinetic of these rodenticides in dogs is lacking. We analysed blood and faeces from five accidentally exposed dogs and 110 healthy dogs by reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry. The aim of the study was to estimate elimination of brodifacoum, bromadiolone and difenacoum after acute exposure, calculate the half-lives of these rodenticides in dogs, estimate faecal elimination in a litter of puppies born, and further to identify the extent of AR exposure in a healthy dog population. Results: Three dogs were included after single ingestions of brodifacoum; two dogs ingested bromadiolone and one dog ingested difenacoum. Maximum concentrations in faeces were found after day 2-3 for all ARs. The distribution half-lives were 1-10 days for brodifacoum, 1-2 days for bromadiolone and 10 days for difenacoum. Brodifacoum and difenacoum had estimated terminal half-lives of 200-330 days and 190 days, respectively. In contrast, bromadiolone had an estimated terminal half-life of 30 days. No clinical signs of poisoning or coagulopathy were observed in terminal elimination period. In blood, the terminal half-life of brodifacoum was estimated to 8 days. Faeces from a litter of puppies born from one of the poisoned dogs were examined, and measurable concentrations of brodifacoum were detected in all samples for at least 28 days after parturition. A cross-sectional study of 110 healthy domestic dogs was performed to estimate ARs exposure in a dog population. Difenacoum was detected in faeces of one dog. Blood and faecal samples from the remaining dogs were negative for all ARs. Conclusions: Based on the limited pharmacokinetic data from these dogs, our results suggest that ARs have a biphasic elimination in faeces using a two-compartment elimination kinetics model. We have shown that faecal analysis is suitable and reliable for the assessment of ARs exposure in dogs and a tool for estimating the AR half-lives. Half-lives of ARs could be a valuable indicator in the exposed dogs and provides important information for veterinarians monitoring AR exposure and assessment of treatment length in dogs.

Journal of Wildlife Diseases, Oct 9, 2019

High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerou... more High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerous reports of secondary exposure through predation. Because of widespread distribution of the red fox (Vulpes vulpes), they may act as sentinels for small mammal-hunting predators in rural, suburban, and urban areas. No AR surveillance in wild mammals with analyses of residues in feces has been conducted throughout a single country. We collected 163 fecal samples from presumed healthy red foxes from 18 out of 19 counties in Norway. The foxes were shot during regular hunting between January and December 2016 and samples collected directly after death. Fecal samples were analyzed for six ARs: brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen. We detected ARs in 54% (75/139) of the animals. Brodifacoum was most frequently detected (46%; 64/139), followed by coumatetralyl (17%; 23/139), bromadiolone (16%; 22/139), difenacoum (5%; 7/139), difethialone (1%; 2/139), and flocoumafen (1%; 2/139). More than one substance was detected in 40% (30/75) of the positive foxes, and 7% (5/75) of these animals were exposed to four different ARs. There were no statistically significant seasonal, age, or sex differences in foxes after exposure to one AR compound. We found a significant difference in occurrence of brodifacoum and coumatetralyl in foxes from different geographical areas. These findings demonstrate fecal analyses as a valuable method of detecting AR exposure in red foxes. We suggest using direct fecal sampling with analyses as a method to evaluate the occurrence of ARs in live endangered wildlife in connection with radio tagging or collaring operations.

Journal of Liquid Chromatography & Related Technologies, Oct 23, 2017

ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercrit... more ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercritical fluid chromatography (UHPSFC), opening up for fast analysis and high-resolution separations. The development of new and more robust systems also makes the technique more interesting for bioanalytical analysis, where the need for reproducible and fast analysis with little downtime is great. One area where the use of UHPSFC could become a useful tool is in the separation of structural isomers of new psychoactive substances (NPS). 2-, 3-, and 4- structural isomers of fluoroamphetamine, fluoromethamphetamine, and methylmethcathinone, isomeric pairs of the synthetic cannabinoids UR-144/UR-144 degradant, XLR-11/XLR-11 degradant, JWH-015/JWH-073, and JWH-019/JWH-122, as well as amphetamine and several stable isotope-labeled amphetamine internal standards were separated with UHPSFC-MS/MS and compared with ultrahigh-pressure liquid chromatography (UHPLC) MS/MS. NPS isomers that were difficult to separate with reversed-phase UHPLC-MS/MS were separated by UHPSFC; in most cases with an orthogonal retention order to UHPLC. In contrast to the behavior seen when using reversed-phase UHPLC, the deuterated amphetamines eluted later than amphetamine with UHPSFC. 13C6-labeled amphetamine coeluted with amphetamine for all conditions, making this the best choice of an internal standard. GRAPHICAL ABSTRACT

Journal of Veterinary Diagnostic Investigation, Jun 1, 2020

Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide conc... more Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide concern, but few methods exist to determine residue levels in live animals. Traditional liver detection methods preclude determining exposure in live wildlife. To determine the value of assessing AR exposure by fecal analysis, we compared fecal and liver residues of ARs in the same animals. We collected liver and fecal samples from 40 apparently healthy red foxes (Vulpes vulpes) potentially exposed to ARs, and quantified brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen residues by liquid chromatographytandem mass spectrometry. Residues of ARs were detected in 53% of the fecal samples and 83% of the liver samples. We found good concordance between AR residues in feces and liver for coumatetralyl, difenacoum, and difethialone. Bromadiolone occurred in significantly greater frequency in livers compared to feces, but no significant difference in concentration between feces and liver in individual foxes could be detected. Brodifacoum displayed a significant difference in concentration and occurrence of positive samples between liver and feces. Our findings demonstrate that fecal analysis of ARs provides a feasible and valuable non-lethal means of determine AR exposure in live wildlife.

Journal of Chromatography B, Nov 1, 2014

An ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was... more An ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the determination of zopiclone and zolpidem in whole blood, for use in cases with suspected driving under influence of drugs (DUID) and autopsy cases. Sample preparation was performed with liquid-liquid extraction (LLE) using ethyl acetate/n-heptane (80:20, v/v) and 0.1 mL whole blood. Deuterated analogues were used as internal standards (IS) for both compounds. The compounds were separated using a reversed phase C 18-column (2.1mm x 100 mm, 1.7 µm), with a flow rate of 0.5 mL/min, 1µL injected and gradient elution with 5 mM ammonium formate pH 10.2 and acetonitrile. Quantification was done by MS/MS using multiple reaction monitoring (MRM) in positive mode. The run time of the method was 4.5 minutes including equilibration time. The calibration curves of extracted whole blood standards were fitted by linear-order calibration curves weighted 1/x, with R 2 values above 0.999 for both compounds. Intermediate precision and accuracies (bias) were 2.4-12.9% RSD and from-5.9 to 6.8%, respectively. Recoveries of the compounds were ≥ 70%. The lower limit of quantification A c c e p t e d M a n u s c r i p t 2 (LLOQ) for zopiclone was 0.50 nmol/L (0.19 ng/mL) or 0.05 pg injected on column, and 3.5 nmol/mL (1.10 ng/mL) for zolpidem, or 0.27 pg injected on column. The limit of detection (LOD) was 0.2 nmol/L (0.08 ng/mL) for zopiclone and 0.3 nmol/L (0.09 ng/mL) for zolpidem. Matrix effects (ME) were between 108-115% when calculated against IS. A comparison with former confirmation LC-MS method at the Norwegian Institute of Public Health, Division of Forensic Medicine (NIPH) was performed during method validation. Good correlation was seen for both compounds. The method has been running on a routine basis for two years, and has proven to be very robust and reliable with satisfactory long term precision and bias and with results for external quality samples corresponding well to consensus mean or median. Zopiclone and zolpidem concentrations in post mortem and ante mortem cases were reported. The method also meets the requirements of the legislative limits for driving under the influence of non-alcohol drugs introduced in the Norwegian Road Traffic Act Law from 2012.

Acta Veterinaria Scandinavica, Jan 17, 2018

Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few... more Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few reports of the elimination kinetics and half-lives in this species have been published. Our objectives were to develop and validate a new method for the quantification of anticoagulant rodenticides in canine blood and faeces using reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and apply the method on a case of anticoagulant rodenticide intoxication. Results: Sample preparation was liquid-liquid extraction. Six anticoagulant rodenticides were separated using a UPLC ® BEH C 18-column with a mobile phase consisting of 5 mM ammonium formate buffer pH 10.2 and methanol. MS/MS detection was performed with positive electrospray ionization and two multiple reaction monitoring transitions. The limits of quantification were set at the levels of the lowest calibrator (1.5-2.7 ng/mL or ng/g). The method was successfully applied to a case from a dog accidentally poisoned with anticoagulant rodenticide. Coumatetralyl and brodifacoum concentrations were determined from serial blood and faecal samples. A terminal half-life of at least 81 days for coumatetralyl in blood was estimated, which is longer than previous reported in other species. A slow elimination of brodifacoum from the faeces was found, with traces still detectable in the faeces at day 513. Conclusions: This study offers a new method of detection and quantification of six frequently used anticoagulant rodenticides in canine faeces. Such drugs might cause serious health effects and it is important to be able to detect these drugs, to initiate proper treatment. The very long elimination half-lives detected in our study is important to be aware of in assessment of anticoagulant rodenticide burden to the environment.

Journal of Liquid Chromatography & Related Technologies

ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercrit... more ABSTRACT The use of sub-2 µm particles columns is finding its use in ultrahigh-pressure supercritical fluid chromatography (UHPSFC), opening up for fast analysis and high-resolution separations. The development of new and more robust systems also makes the technique more interesting for bioanalytical analysis, where the need for reproducible and fast analysis with little downtime is great. One area where the use of UHPSFC could become a useful tool is in the separation of structural isomers of new psychoactive substances (NPS). 2-, 3-, and 4- structural isomers of fluoroamphetamine, fluoromethamphetamine, and methylmethcathinone, isomeric pairs of the synthetic cannabinoids UR-144/UR-144 degradant, XLR-11/XLR-11 degradant, JWH-015/JWH-073, and JWH-019/JWH-122, as well as amphetamine and several stable isotope-labeled amphetamine internal standards were separated with UHPSFC-MS/MS and compared with ultrahigh-pressure liquid chromatography (UHPLC) MS/MS. NPS isomers that were difficult to separate with reversed-phase UHPLC-MS/MS were separated by UHPSFC; in most cases with an orthogonal retention order to UHPLC. In contrast to the behavior seen when using reversed-phase UHPLC, the deuterated amphetamines eluted later than amphetamine with UHPSFC. 13C6-labeled amphetamine coeluted with amphetamine for all conditions, making this the best choice of an internal standard. GRAPHICAL ABSTRACT

Acta Veterinaria Scandinavica

Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes ... more Background: Exposure to anticoagulant rodenticides (ARs) in dogs is among the most common causes of poisoning in small animal practice, but information about toxicokinetic of these rodenticides in dogs is lacking. We analysed blood and faeces from five accidentally exposed dogs and 110 healthy dogs by reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry. The aim of the study was to estimate elimination of brodifacoum, bromadiolone and difenacoum after acute exposure, calculate the half-lives of these rodenticides in dogs, estimate faecal elimination in a litter of puppies born, and further to identify the extent of AR exposure in a healthy dog population. Results: Three dogs were included after single ingestions of brodifacoum; two dogs ingested bromadiolone and one dog ingested difenacoum. Maximum concentrations in faeces were found after day 2-3 for all ARs. The distribution half-lives were 1-10 days for brodifacoum, 1-2 days for bromadiolone and 10 days for difenacoum. Brodifacoum and difenacoum had estimated terminal half-lives of 200-330 days and 190 days, respectively. In contrast, bromadiolone had an estimated terminal half-life of 30 days. No clinical signs of poisoning or coagulopathy were observed in terminal elimination period. In blood, the terminal half-life of brodifacoum was estimated to 8 days. Faeces from a litter of puppies born from one of the poisoned dogs were examined, and measurable concentrations of brodifacoum were detected in all samples for at least 28 days after parturition. A cross-sectional study of 110 healthy domestic dogs was performed to estimate ARs exposure in a dog population. Difenacoum was detected in faeces of one dog. Blood and faecal samples from the remaining dogs were negative for all ARs. Conclusions: Based on the limited pharmacokinetic data from these dogs, our results suggest that ARs have a biphasic elimination in faeces using a two-compartment elimination kinetics model. We have shown that faecal analysis is suitable and reliable for the assessment of ARs exposure in dogs and a tool for estimating the AR half-lives. Half-lives of ARs could be a valuable indicator in the exposed dogs and provides important information for veterinarians monitoring AR exposure and assessment of treatment length in dogs.

Journal of Veterinary Diagnostic Investigation

Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide conc... more Exposure of wildlife and domestic animals to anticoagulant rodenticides (ARs) is a worldwide concern, but few methods exist to determine residue levels in live animals. Traditional liver detection methods preclude determining exposure in live wildlife. To determine the value of assessing AR exposure by fecal analysis, we compared fecal and liver residues of ARs in the same animals. We collected liver and fecal samples from 40 apparently healthy red foxes ( Vulpes vulpes) potentially exposed to ARs, and quantified brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen residues by liquid chromatography–tandem mass spectrometry. Residues of ARs were detected in 53% of the fecal samples and 83% of the liver samples. We found good concordance between AR residues in feces and liver for coumatetralyl, difenacoum, and difethialone. Bromadiolone occurred in significantly greater frequency in livers compared to feces, but no significant difference in concentration...

High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerou... more High occurrence of anticoagulant rodenticides (ARs) in wildlife is a rising concern, with numerous reports of secondary exposure through predation. Because of widespread distribution of the red fox (Vulpes vulpes), they may act as sentinels for small mammal-hunting predators in rural, suburban, and urban areas. No AR surveillance in wild mammals with analyses of residues in feces has been conducted throughout a single country. We collected 163 fecal samples from presumed healthy red foxes from 18 out of 19 counties in Norway. The foxes were shot during regular hunting between January and December 2016 and samples collected directly after death. Fecal samples were analyzed for six ARs: brodifacoum, bromadiolone, coumatetralyl, difenacoum, difethialone, and flocoumafen. We detected ARs in 54% (75/139) of the animals. Brodifacoum was most frequently detected (46%; 64/139), followed by coumatetralyl (17%; 23/139), bromadiolone (16%; 22/139), difenacoum (5%; 7/139), difethialone (1%; 2/139), and flocoumafen (1%; 2/139). More than one substance was detected in 40% (30/75) of the positive foxes, and 7% (5/75) of these animals were exposed to four different ARs. There were no statistically significant seasonal, age, or sex differences in foxes after exposure to one AR compound. We found a significant difference in occurrence of brodifacoum and coumatetralyl in foxes from different geographical areas. These findings demonstrate fecal analyses as a valuable method of detecting AR exposure in red foxes. We suggest using direct fecal sampling with analyses as a method to evaluate the occurrence of ARs in live endangered wildlife in connection with radio tagging or collaring operations.

Journal of clinical laboratory analysis, Jan 25, 2018

Phosphatidylethanols (PEths) are specific, direct alcohol biomarkers that can be determined in hu... more Phosphatidylethanols (PEths) are specific, direct alcohol biomarkers that can be determined in human blood to distinguish between heavy and social drinking. PEth 16:0/18:1 is among the most predominant PEth homologues in human blood. The aim of the study was to develop a high throughput and sensitive UHPLC-MS/MS method for the determination of PEth 16:0/18:1 in whole blood. Whole blood samples were prepared by 96-well supported liquid extraction (SLE). Extracted samples were analyzed for PEth 16:0/18:1 by reversed phase UHPLC-MS/MS. The developed UHPLC-MS/MS method was fully validated in whole blood with PEth 16:0/18:1-D as internal standard. Intermediate precision and intermediate accuracy were within ≤± 12% and ≤± 17%, respectively, at PEth 16:0/18:1 concentrations of 1.4-2112 ng/mL (2.0-3004 nmol/L). Limit of quantification (LOQ) was 1.7 ng/mL (2.4 nmol/L). For the first time, 96-well SLE was used for preparation of a PEth homologue in biological samples. A mixture of tert-butyl ...

Acta Veterinaria Scandinavica

Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few... more Background: Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few reports of the elimination kinetics and half-lives in this species have been published. Our objectives were to develop and validate a new method for the quantification of anticoagulant rodenticides in canine blood and faeces using reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and apply the method on a case of anticoagulant rodenticide intoxication. Results: Sample preparation was liquid-liquid extraction. Six anticoagulant rodenticides were separated using a UPLC ® BEH C 18-column with a mobile phase consisting of 5 mM ammonium formate buffer pH 10.2 and methanol. MS/MS detection was performed with positive electrospray ionization and two multiple reaction monitoring transitions. The limits of quantification were set at the levels of the lowest calibrator (1.5-2.7 ng/mL or ng/g). The method was successfully applied to a case from a dog accidentally poisoned with anticoagulant rodenticide. Coumatetralyl and brodifacoum concentrations were determined from serial blood and faecal samples. A terminal half-life of at least 81 days for coumatetralyl in blood was estimated, which is longer than previous reported in other species. A slow elimination of brodifacoum from the faeces was found, with traces still detectable in the faeces at day 513. Conclusions: This study offers a new method of detection and quantification of six frequently used anticoagulant rodenticides in canine faeces. Such drugs might cause serious health effects and it is important to be able to detect these drugs, to initiate proper treatment. The very long elimination half-lives detected in our study is important to be aware of in assessment of anticoagulant rodenticide burden to the environment.