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2.
J Equine Vet Sci ; 133: 104974, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38145776

ABSTRACT

This study aimed to determine the efficacy of instilling extract of the pitcher plant around the palmar digital nerves of horses to ameliorate digit pain causing lameness. Five mixed breed horses were recruited. Horses were determined to be lame because of pain in the distal portion of one or both thoracic limbs by a positive response to a basisesamoid nerve block using 2%^mepivacaine hydrochloride. Gait was evaluated pre- and post-nerve block at 30 min, 3, 7,14 and 21 days. At the 3-week evaluation, the basisesamoid nerve block was repeated using the extract, and the gait was evaluated at similar times. Lameness was evaluated objectively using a wireless, inertial, sensor-based, motion analysis system. The basisesamoid nerve block significantly ameliorated lameness at 30 min when gait was evaluated, but it had no significant effect on lameness after this time. The product containing extract of the pitcher plant had no significant effect on lameness when administered as a basisesamoid nerve block at any time. Extract of the pitcher plant administered adjacent to the medial and lateral palmar digital nerves (i.e., a basisesamoid nerve block) had no efficacy in ameliorating lameness in the distal portion of one or both thoracic limbs. Extract of the pitcher plant likely has no value for treating horses for chronic pain when administered as a regional nerve block.


Subject(s)
Horse Diseases , Sarraceniaceae , Horses , Animals , Lameness, Animal/drug therapy , Lameness, Animal/etiology , Pain/drug therapy , Pain/etiology , Pain/veterinary , Mepivacaine/pharmacology , Mepivacaine/therapeutic use , Gait , Horse Diseases/drug therapy
3.
Clin Geriatr Med ; 39(4): 647-658, 2023 11.
Article in English | MEDLINE | ID: mdl-37798070

ABSTRACT

Older patients' ED visits rose 30% over 5 years and EDs are now examining geriatric emergency department (GED) models of care. The 3 Ps model focuses on the GED's People, Processes, and the Place to provide a framework for GED development. Key resources include the: GED Collaborative, GED Guidelines, and Geriatric Emergency Department Accreditation process. Core to a GED's operation is its care processes including: (1) General approaches; (2) Screening for high-risk conditions; (3) Enhanced assessment; (4) Workflow alterations; and (5) Transitions. This article provides practical guidance to EDs seeking to enhance the ED experience of older people and improve the quality of their outcomes.


Subject(s)
Emergency Service, Hospital , Geriatric Assessment , Humans , Aged
4.
Nature ; 620(7973): 344-350, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37495695

ABSTRACT

Kimberlites are volatile-rich, occasionally diamond-bearing magmas that have erupted explosively at Earth's surface in the geologic past1-3. These enigmatic magmas, originating from depths exceeding 150 km in Earth's mantle1, occur in stable cratons and in pulses broadly synchronous with supercontinent cyclicity4. Whether their mobilization is driven by mantle plumes5 or by mechanical weakening of cratonic lithosphere4,6 remains unclear. Here we show that most kimberlites spanning the past billion years erupted about 30 million years (Myr) after continental breakup, suggesting an association with rifting processes. Our dynamical and analytical models show that physically steep lithosphere-asthenosphere boundaries (LABs) formed during rifting generate convective instabilities in the asthenosphere that slowly migrate many hundreds to thousands of kilometres inboard of rift zones. These instabilities endure many tens of millions of years after continental breakup and destabilize the basal tens of kilometres of the cratonic lithosphere, or keel. Displaced keel is replaced by a hot, upwelling mixture of asthenosphere and recycled volatile-rich keel in the return flow, causing decompressional partial melting. Our calculations show that this process can generate small-volume, low-degree, volatile-rich melts, closely matching the characteristics expected of kimberlites1-3. Together, these results provide a quantitative and mechanistic link between kimberlite episodicity and supercontinent cycles through progressive disruption of cratonic keels.

5.
Vet Surg ; 51(2): 279-285, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34964510

ABSTRACT

OBJECTIVE: To compare a 2% lidocaine solution containing 5 µg/ml (1:200 000) epinephrine with 2% mepivacaine for reducing lameness in horses after use in proximal nerve blocks. STUDY DESIGN: Experimental randomized crossover. ANIMALS: Six adult horses with naturally occurring forelimb lameness. METHODS: Horses were evaluated using an inertial gait sensor system. Lameness was measured as a vector sum (VS). Following baseline lameness examination, median and ulnar nerve blocks were performed with lidocaine/epinephrine (0.5 mg epinephrine added to 50 ml of 2% lidocaine immediately prior to administration) or an equal volume of 2% mepivacaine. Horses were trotted at 5 min and then at 30 min intervals for 150 min. After 24 h, nerve blocks were repeated using the other local anesthetic. Data were evaluated using linear models. RESULTS: The reduction in the VS did not differ after nerve blocks with lidocaine/epinephrine or mepivacaine (P = .791). Mean time to VS <8.5 mm (n = 5) was 5 and 9.6 min for lidocaine/epinephrine and mepivacaine, respectively. For one horse, VS was not reduced to <8.5 mm with either treatment (this horse had the highest VS before treatments were administered). The decrease in VS to <8.5 mm lasted for 150 min in both treatment groups. CONCLUSION: The outcomes of the median and ulnar nerve blocks performed with 2% lidocaine with epinephrine did not differ from blocks performed with 2% mepivacaine. CLINICAL RELEVANCE: Two percent lidocaine with epinephrine may serve as an adequate replacement for proximal nerve blocks when mepivacaine is unavailable.


Subject(s)
Horse Diseases , Nerve Block , Anesthetics, Local/pharmacology , Animals , Epinephrine , Forelimb , Gait , Horse Diseases/drug therapy , Horses , Lameness, Animal/drug therapy , Lidocaine/pharmacology , Mepivacaine/pharmacology , Nerve Block/veterinary
6.
Cureus ; 13(7): e16526, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34430136

ABSTRACT

Objectives This research describes the experiences of emergency departments (EDs) with geriatric fall programs and qualitatively synthesizes lessons learned to inform other EDs planning new fall program implementation. Methods By using grounded theory, we conducted semi-structured, open-ended telephone/skype interviews of emergency physicians and geriatric providers recruited from a purposeful sampling technique. The interviews were transcribed and reviewed by two investigators. The codes were generated and listed, and common concepts emerged. Lastly, the final codes were organized into concepts and themes with the aim to create a strong coding structure. Result The main lessons learned are: (1) understand the hospital's existing local environment and resources, (2) utilize champions and interdisciplinary teams, (3) acknowledge that specific fall assessment tools and interventions vary widely between institutions, (4) engage in routine plan-do-study-act (PDSA) cycles to improve the quality of fall initiatives, and (5) operate under the principle that falls are a syndrome, which must be incorporated within the multifactorial medical needs of geriatric fall patients. Conclusion Based on the lessons learned from our ED fall implementation pioneers, implementing an effective geriatric fall protocol in an ED setting is complicated. Understanding a hospital's resources, assigning champions, working as an interdisciplinary team, choosing proper fall assessment tools/interventions, and completing regular PDSA cycles are important lessons for ED programs planning to implement their own ED fall programs.

7.
Addict Behav ; 114: 106729, 2021 03.
Article in English | MEDLINE | ID: mdl-33229102

ABSTRACT

This investigation utilized a large sample of individuals undergoing substance use treatment to examine the CES-D's structural validity and establish its predictive utility relative to treatment discharge. The sample included 5750 individuals who were receiving substance abuse treatment at 19 different residential treatment facilities. The CES-D was administered to participants over the course of their time in a residential inpatient substance use treatment program. The present study used a split sample method to conduct both exploratory (EFA) and confirmatory (CFA) factor analyses. Results of both the EFA and CFA indicated that the CES-D contains three first order factors measuring negative mood, positive affect, and interpersonal interactions as well as a second-order high score factor which can be used to guide interpretation and symptom monitoring. Individuals receiving residential treatment fell into one of three distinct groups based on their CES-D scores, and that their scores (and subsequent trajectories of scores over time) were differentially related to discharge status. Implications for practice and the utility of the CES-D within substance use populations are discussed.


Subject(s)
Depression , Substance-Related Disorders , Factor Analysis, Statistical , Humans , Psychiatric Status Rating Scales , Psychometrics , Reproducibility of Results , Residential Treatment , Substance-Related Disorders/therapy , Treatment Outcome
8.
Am J Vet Res ; 81(5): 394-399, 2020 May.
Article in English | MEDLINE | ID: mdl-32343179

ABSTRACT

OBJECTIVE: To compare the speed of onset and analgesic effect of mepivacaine deposited within or immediately outside the neurovascular bundle at the base of the proximal sesamoid bones in horses. ANIMALS: 6 horses with naturally occurring forefoot-related lameness. PROCEDURES: In a crossover study design, horses were randomly assigned to receive 1 of 2 treatments first, with the second treatment administered 3 to 7 days later. Trotting gait was analyzed with an inertial sensor-based motion analysis system immediately before treatment to determine degree of lameness. Afterward, ultrasound guidance was used to inject 2% mepivacaine hydrochloride around the palmar digital nerves of the affected forelimb at the level of the base of the proximal sesamoid bones either within the subcircumneural space or outside the circumneural sheath. After injection, gait was reevaluated at 5-minute intervals for 45 minutes. RESULTS: Mepivacaine deposition outside the circumneural sheath did not resolve lameness in any horse; for 3 horses, the mean time to 70% reduction of initial vertical head movement was 13.3 minutes, and the remaining 3 horses had no such reduction at any point. Mepivacaine deposition within the subcircumneural space resulted in a mean time to 70% reduction of initial vertical head movement of 6.7 minutes and mean time to resolution of lameness of 21.7 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that when peripheral nerves of horses lie within a sheath, local anesthetic solution should be deposited within the sheath for an effective nerve block. If local anesthetic solution is deposited outside the sheath, the nerve block may yield erroneous results.


Subject(s)
Horse Diseases , Sesamoid Bones , Analgesics/pharmacology , Animals , Cross-Over Studies , Forelimb , Gait/drug effects , Horses , Lameness, Animal , Mepivacaine/pharmacology
9.
J Appl Gerontol ; 39(8): 871-879, 2020 08.
Article in English | MEDLINE | ID: mdl-30451060

ABSTRACT

The traditional model of emergency care no longer fits the growing needs of the over 20 million older adults annually seeking emergency department care. In 2007 a tailored "geriatric emergency department" model was introduced and rapidly replicated among hospitals, rising steeply over the past 5 years. This survey examined all U.S. emergency departments self-identifying themselves as Geriatric Emergency Departments (GEDs) and providing enhanced geriatric emergency care services. It was guided by the recently adopted Geriatric Emergency Department Guidelines and examined domains including, GED identity, staffing, and administration; education, equipment, and supplies; policies, procedures, and protocols; follow-up and transitions of care; and quality improvement. Results reveal a heterogeneous mix of GED staffing, procedures, physical environments and that GEDs' familiarity with the GED Guidelines is low. Findings will inform emergency departments and gerontologists nationwide about key GED model elements and will help hospitals to improve ED services for their older adult patients.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Geriatrics/statistics & numerical data , Guidelines as Topic/standards , Aged , Delivery of Health Care , Emergency Service, Hospital/trends , Humans , Surveys and Questionnaires , United States
10.
Am J Vet Res ; 81(1): 13-16, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31887088

ABSTRACT

OBJECTIVE: To assess onset of analgesia for 3% chloroprocaine hydrochloride and 2% mepivacaine hydrochloride when used for median and ulnar nerve blocks in lame horses. ANIMALS: 6 naturally lame horses. PROCEDURES: A crossover experiment was conducted. Horses were assigned to 1 of 2 treatment groups (3% chloroprocaine or 2% mepivacaine first). Median and ulnar nerve blocks were performed in the lame limb with the assigned treatment. Lameness was objectively evaluated before treatment administration and at various points for 120 minutes after treatment with a wireless inertial sensor-based motion analysis system. Following a 7-day washout period, horses then received the other treatment and lameness evaluations were repeated. RESULTS: Median and ulnar nerve blocks performed with 3% chloroprocaine resulted in more consistent, rapid, and profound amelioration of lameness than did blocks performed with 2% mepivacaine. Lameness decreased more between 20 and 40 minutes after injection when 3% chloroprocaine was used than when 2% mepivacaine was used. Complete resolution of lameness was detected a mean of 9 minutes after injection when median and ulnar nerve blocks were performed with 3% chloroprocaine and a mean of 28 minutes after injection when performed with 2% mepivacaine. CONCLUSIONS AND CLINICAL RELEVANCE: 3% chloroprocaine had a more rapid onset and provided better analgesia for median and ulnar nerve blocks in horses with naturally occurring lameness, compared with 2% mepivacaine. These favorable properties suggest that 3% chloroprocaine would be useful for performance of median and ulnar regional nerve blocks during complicated lameness evaluations.


Subject(s)
Gait/drug effects , Horse Diseases/drug therapy , Lameness, Animal/drug therapy , Nerve Block/veterinary , Pain/veterinary , Procaine/analogs & derivatives , Analgesia/veterinary , Anesthetics, Local/pharmacology , Anesthetics, Local/therapeutic use , Animals , Cross-Over Studies , Horses , Male , Mepivacaine/pharmacology , Mepivacaine/therapeutic use , Pain/drug therapy , Procaine/pharmacology , Procaine/therapeutic use
11.
J Equine Vet Sci ; 79: 35-38, 2019 08.
Article in English | MEDLINE | ID: mdl-31405497

ABSTRACT

Squamous cell carcinoma (SCC) is one of the most common malignant neoplasms in horses, but lingual SCC has seldom been reported. On separate occasions, a 12-year-old American Quarter Horse mare and an 18-year-old American Saddlebred stallion were presented to the Auburn University Large Animal Teaching Hospital for evaluation of weight loss, dysphagia, and ptyalism. Evaluation of each horse included physical examination, skull radiographs, oral examination, complete blood count and serum biochemistry profile, endoscopic evaluation of the mouth, and biopsy of tissue from a lesion found on the tongue. Histopathologic assessment of tissue harvested from the lingual lesions led to a diagnosis of SCC in each case. The diagnosis prompted euthanasia for one horse, but radiation therapy appeared to delay the progression of the lesion in the other horse.


Subject(s)
Carcinoma, Squamous Cell/veterinary , Head and Neck Neoplasms/veterinary , Horse Diseases , Squamous Cell Carcinoma of Head and Neck/veterinary , Tongue Neoplasms/veterinary , Animals , Carcinoma, Squamous Cell/pathology , Female , Head and Neck Neoplasms/pathology , Horse Diseases/pathology , Horses , Male , Squamous Cell Carcinoma of Head and Neck/pathology , Tongue Neoplasms/pathology , United States
12.
J Equine Vet Sci ; 75: 9-13, 2019 04.
Article in English | MEDLINE | ID: mdl-31002100

ABSTRACT

The median nerve, along with the ulnar nerve, is often anesthetized when performing a lameness examination in horses. Because of the close proximity of the median nerve to the cubital joint, proximal migration of local anesthetic might ameliorate pain originating from the cubital joint. The objective of this study was to determine if a median nerve block will ameliorate lameness caused by pain in the cubital joint. A forelimb lameness was induced in six healthy horses by injecting 100 ng of recombinant equine interleukin 1 beta (IL-1ß) into the cubital joint. The median nerve of the lame leg was anesthetized using 10 mL of 2% mepivacaine hydrochloride. A successful median nerve block was confirmed by loss of skin sensation at the medial aspect of the pastern and typical changes in thermographic images. Gait was assessed before and at 20, 40, and 60 minutes after the median nerve block using an inertial sensor-based motion analysis system (Lameness Locator; Equinosis LLC, Columbia, MO). A full-factorial repeated measures analysis of variance was used to compare treatment effect across time. IL-1ß administration resulted in significant transient lameness in all horses (P < .0001). The median nerve block was successfully performed in all horses and did not result in significant improvement (P = .32) of lameness as quantified by the total differential head vector sum. This result has relevant clinical application as it suggests when performing a lameness examination, it is unlikely that blocking the median nerve with 10 mL of local anesthetic will ameliorate pain originating from the cubital joint.


Subject(s)
Horse Diseases , Lameness, Animal , Animals , Gait , Horses , Median Nerve , Pain/veterinary
13.
Vet Rec ; 184(5): 155, 2019 Feb 02.
Article in English | MEDLINE | ID: mdl-30661018

ABSTRACT

The objective of this study was to determine if buffering mepivacaine HCL (mepHCl) with sodium bicarbonate (NaHCO3) would significantly decrease the time to onset of analgesia when performing median and ulnar nerve blocks in naturally lame horses. Median and ulnar nerve blocks were performed on the naturally lame limb of nine horses during two separate study periods, with a minimum washout period of three days between study periods. Nerve blocks were performed by administering mepHCl alone or mepHCl mixed with NaHCO3 (nine parts 2 per cent mepHCl to one part 8.4 per cent NaHCO3). Lameness was evaluated objectively using a wireless, inertial, sensor-based, motion analysis system (Lameness Locator) prior to the high regional nerve block and every five minutes following administration of the nerve block for 75 min. Resolution of lameness occurred earlier and was more profound for horses administered median and ulnar nerve blocks performed with mepHCl and NaHCO3 than when these nerve blocks were performed using only mepHCl.


Subject(s)
Analgesia/veterinary , Anesthetics, Local/pharmacology , Horse Diseases/drug therapy , Lameness, Animal/drug therapy , Mepivacaine/pharmacology , Nerve Block/veterinary , Sodium Bicarbonate/pharmacology , Analgesia/methods , Animals , Female , Horses , Male , Time Factors , Treatment Outcome
14.
Front Vet Sci ; 6: 478, 2019.
Article in English | MEDLINE | ID: mdl-32039245

ABSTRACT

Orchiectomy is performed in some species using only sedation and local anesthesia to decrease the expense of performing the procedure using general anesthesia. The objective of this study was to determine if dogs can be castrated safely and painlessly by using only sedation and local anesthesia. After dogs were sedated with intramuscularly administered xylazine (1 mg/kg) and subanesthetic ketamine (1 mg/kg), testes and skin were anesthetized with 2% lidocaine (6 mg/kg, total dose) buffered with sodium bicarbonate. Systolic, diastolic, and mean blood pressures; heart and respiratory rates; and movement scores were determined before and during surgery when manipulations were most likely to cause pain. No dog reacted substantially to injection of the combination of sedatives, and no dog reacted noticeably to injection of lidocaine. During surgery, the average heart rate was reduced from baseline by 40-60 beats per minute, and the average respiratory rate was reduced by ~10 breaths per minute. An overall reduction of arterial blood pressures was observed. All but one dog moved purposely in response to a toe pinch at the end of surgery. We found that sedating dogs intramuscularly with xylazine and a sub-anesthetic dose of ketamine and administering lidocaine at the incision site and intratesticularly allowed dogs to be castrated humanely and avoided the expense of general anesthesia and the need for hospitalization.

15.
Am J Vet Res ; 79(10): 1028-1034, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30256149

ABSTRACT

OBJECTIVE To determine whether addition of epinephrine to a lidocaine solution would prolong and potentiate the efficacy of a palmar digital nerve block (PDNB) in horses. ANIMALS 6 adult horses with naturally occurring forefoot lameness. PROCEDURES Initially, a PDNB with a 2% lidocaine solution was performed on the affected foot of each horse. Three days later, the PDNB was repeated with a 1% lidocaine solution or a 1% lidocaine solution containing epinephrine (dilution, 1:200,000). After another 3-day washout period, the PDNB was repeated with the treatment opposite that administered for the second PDNB. Gait was analyzed with a computerized lameness analysis system and heart rate and extent of skin sensation between the heel bulbs of the blocked foot were evaluated at predetermined times for 2 hours after each PDNB. RESULTS Efficacy and duration of the PDNB did not differ significantly between the 2% and 1% lidocaine treatments. The addition of epinephrine to the 1% lidocaine solution improved the efficacy and prolonged the duration of the PDNB. It also resulted in a positive correlation between skin desensitization and amelioration of lameness. Median heart rate remained unchanged throughout the observation period for all 3 treatments. No adverse effects associated with the PDNBs were observed. CONCLUSIONS AND CLINICAL RELEVANCE Addition of epinephrine (dilution, 1:200,000) to a 1% lidocaine solution improved the efficacy and prolonged the duration of a PDNB in horses with naturally occurring lameness and might be clinically useful for lameness evaluations and standing surgery of the forefoot of horses.


Subject(s)
Anesthetics, Local/administration & dosage , Epinephrine/administration & dosage , Foot Diseases/veterinary , Forelimb/injuries , Horse Diseases/surgery , Nerve Block/veterinary , Anesthetics, Local/pharmacology , Animals , Cross-Over Studies , Drug Therapy, Combination , Epinephrine/pharmacology , Foot Diseases/surgery , Gait/drug effects , Horses , Lameness, Animal , Lidocaine/administration & dosage , Lidocaine/pharmacology , Male , Pain/drug therapy , Pain/veterinary , Pain Measurement/veterinary
17.
Environ Sci Technol ; 51(24): 14055-14064, 2017 Dec 19.
Article in English | MEDLINE | ID: mdl-29182871

ABSTRACT

Contaminated sites pose ecological and human-health risks through exposure to contaminated soil and groundwater. Whereas we can readily locate, monitor, and track contaminants in groundwater, it is harder to perform these tasks in the vadose zone. In this study, tree-core samples were collected at a Superfund site to determine if the sample-collection location around a particular tree could reveal the subsurface location, or direction, of soil and soil-gas contaminant plumes. Contaminant-centroid vectors were calculated from tree-core data to reveal contaminant distributions in directional tree samples at a higher resolution, and vectors were correlated with soil-gas characterization collected using conventional methods. Results clearly demonstrated that directional tree coring around tree trunks can indicate gradients in soil and soil-gas contaminant plumes, and the strength of the correlations were directly proportionate to the magnitude of tree-core concentration gradients (spearman's coefficient of -0.61 and -0.55 in soil and tree-core gradients, respectively). Linear regression indicates agreement between the concentration-centroid vectors is significantly affected by in planta and soil concentration gradients and when concentration centroids in soil are closer to trees. Given the existing link between soil-gas and vapor intrusion, this study also indicates that directional tree coring might be applicable in vapor intrusion assessment.


Subject(s)
Soil Pollutants , Soil , Trees , Gases , Groundwater , Humans
19.
Vet J ; 227: 46-48, 2017 Sep.
Article in English | MEDLINE | ID: mdl-29031330

ABSTRACT

Proximal suspensory desmitis (PSD) is a common cause of lameness in the pelvic limb, but could also affect the thoracic limb of competing and non-competing horses. Most horses diagnosed with PSD in a thoracic limb respond to rest followed by controlled exercise, but in a small percentage of affected horses, lameness persists. In one study, four horses chronically lame because of PSD in a thoracic limb became sound after neurectomy of the deep branch of the lateral palmar nerve (DBLPaN), which innervates the proximal aspect of the suspensory ligament (SL; Guasco et al., 2013). Whether neurectomy of the DBLPaN results in changes in the SL that might predispose the horse to re-injury is not known. The aim of this study was to describe the findings observed during quantitative lameness evaluation, gross and histological examination of the proximal portion of the suspensory ligament (SL) of the thoracic limbs of eight horses after neurectomy of the DBLPaN performed after inducing unilateral PSD by injecting collagenase into the proximal portion of the SL. The clinical response to neurectomy was resolution of lameness in all horses. Muscle fibers of the denervated ligaments presented atrophy and were infiltrated with fat and connective tissue, thereby reducing the strength and elasticity of the ligament.


Subject(s)
Denervation/veterinary , Horse Diseases/surgery , Lameness, Animal/pathology , Ligaments/surgery , Musculoskeletal Diseases/veterinary , Animals , Horse Diseases/pathology , Horses , Lameness, Animal/etiology , Lameness, Animal/surgery , Ligaments/innervation , Ligaments/pathology , Musculoskeletal Diseases/pathology , Musculoskeletal Diseases/surgery
20.
Environ Sci Technol ; 51(18): 10369-10378, 2017 Sep 19.
Article in English | MEDLINE | ID: mdl-28829577

ABSTRACT

Vapor intrusion (VI) by volatile organic compounds (VOCs) in the built environment presents a threat to human health. Traditional VI assessments are often time-, cost-, and labor-intensive; whereas traditional subsurface methods sample a relatively small volume in the subsurface and are difficult to collect within and near structures. Trees could provide a similar subsurface sample where roots act as the "sampler' and are already onsite. Regression models were developed to assess the relation between PCE concentrations in over 500 tree-core samples with PCE concentrations in over 50 groundwater and 1000 soil samples collected from a tetrachloroethylene- (PCE-) contaminated Superfund site and analyzed using gas chromatography. Results indicate that in planta concentrations are significantly and positively related to PCE concentrations in groundwater samples collected at depths less than 20 m (adjusted R2 values greater than 0.80) and in soil samples (adjusted R2 values greater than 0.90). Results indicate that a 30 cm diameter tree characterizes soil concentrations at depths less than 6 m over an area of 700-1600 m2, the volume of a typical basement. These findings indicate that tree sampling may be an appropriate method to detect contamination at shallow depths at sites with VI.


Subject(s)
Environmental Monitoring , Trees/chemistry , Volatile Organic Compounds , Groundwater , Humans , Soil
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