Fort Gibson, OK, United States
Fort Gibson, OK, United States

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Outerbridge M.E.,Government of Bermuda | O'Riordan R.,University College Cork | Fort D.J.,Fort Environmental Laboratories | Davenport J.,University College Cork
Marine Pollution Bulletin | Year: 2016

Total petroleum hydrocarbons, PAH and various trace metal residues were extracted and analyzed from fresh whole diamondback terrapin (Malaclemys terrapin) eggs, whole brackish-water gastropods (terrapin prey) and benthic sediment from anchialine pond environments in Bermuda inhabited by terrapins. Gastropods and terrapin eggs showed higher concentrations of trace metals and organic contaminants than sediments. Conversely, PAHs were mostly found within the sediment and smaller amounts detected in gastropods and terrapin eggs. Results indicated that contaminants in prey were transferred to terrapin eggs, and that concentrations of several contaminants exceeded potentially toxic concentrations for aquatic vertebrates. Necropsy of unhatched eggs from nests that had yielded viable hatchlings showed significantly compromised embryonic development. Bermudian diamondback terrapins reside and feed in brackish wetland habitats characterized by widespread, multifactorial contamination. This study suggests that environmental contamination plays a role in the recorded low hatching success in terrapin eggs in Bermuda. © 2015 Elsevier Ltd.


PubMed | Government of Bermuda, Fort Environmental Laboratories and University College Cork
Type: Journal Article | Journal: Marine pollution bulletin | Year: 2016

Total petroleum hydrocarbons, PAH and various trace metal residues were extracted and analyzed from fresh whole diamondback terrapin (Malaclemys terrapin) eggs, whole brackish-water gastropods (terrapin prey) and benthic sediment from anchialine pond environments in Bermuda inhabited by terrapins. Gastropods and terrapin eggs showed higher concentrations of trace metals and organic contaminants than sediments. Conversely, PAHs were mostly found within the sediment and smaller amounts detected in gastropods and terrapin eggs. Results indicated that contaminants in prey were transferred to terrapin eggs, and that concentrations of several contaminants exceeded potentially toxic concentrations for aquatic vertebrates. Necropsy of unhatched eggs from nests that had yielded viable hatchlings showed significantly compromised embryonic development. Bermudian diamondback terrapins reside and feed in brackish wetland habitats characterized by widespread, multifactorial contamination. This study suggests that environmental contamination plays a role in the recorded low hatching success in terrapin eggs in Bermuda.


Fort D.J.,Fort Environmental Laboratories | Mathis M.,Fort Environmental Laboratories | Fort C.E.,Fort Environmental Laboratories | Fort H.M.,Fort Environmental Laboratories | Bacon J.P.,Bermuda Zoological Society
Environmental Toxicology and Chemistry | Year: 2015

A modified tier 1 Endocrine Disruptor Screening Program (EDSP) 21-d fish short-term reproduction assay (FSTRA) was used to evaluate the effects of sediment exposure from freshwater and brackish ponds in Bermuda on reproductive fecundity and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus). Reproductively active male and female fish were exposed to control sediment and sediment from 2 freshwater ponds (fathead minnow) and 2 marine ponds (killifish) contaminated with polyaromatic hydrocarbons and metals via flow-through exposure for 21d. Reproductive fecundity was monitored daily. At termination, the status of the reproductive endocrine system was assessed by the gonadosomatic index, gonadal histology, plasma steroids (estrogen [E2], testosterone [T], and 11-ketotestosterone [11-KT]), steroidogenic enzymes (aromatase and combined 3β/17β -hydroxysteroid dehydrogenase [3β/17β-HSD]), and plasma vitellogenin (VTG). Decreased reproductive fecundity, lower male body weight, and altered endocrinological measures of reproductive status were observed in both species. Higher plasma T levels in female minnows and 11-KT levels in both male and female minnows and female killifish exposed to freshwater and brackish sediments, respectively. Decreased female E2 and VTG levels and gonadal cytochrome P19 (aromatase) activity were also found in sediment exposed females from both species. No effect on female 3β/17β-HSD activity was found in either species. The FSTRA provided a robust model capable of modification to evaluate reproductive effects of sediment exposure in fish. © 2015 SETAC.


Fort D.J.,Fort Environmental Laboratories | Mathis M.,Fort Environmental Laboratories | Fort C.E.,Fort Environmental Laboratories | Fort H.M.,Fort Environmental Laboratories | And 3 more authors.
Environmental Toxicology and Chemistry | Year: 2016

The impacts of contaminated sediment from 2 ponds in Bermuda on immune function in newly metamorphosed cane toads were examined. In the present study, a partial life-cycle experiment exposing Gosner stage 20 cane toad tadpoles to pond sediment and laboratory culture water through metamorphosis and into a juvenile state was performed. A basic immunology battery, including general necropsy, spleen somatic index, spleen white pulp content, splenocyte tissue density, and splenocyte viability, was conducted in newly metamorphosed Rhinella marina exposed to Bermuda freshwater sediment and baseline specimens collected from 2 separate populations in south Texas and south Florida, USA. Immune function was evaluated using a lymphocyte proliferation assay with subset specimens infected with Mycobacterium chelonae. In the Bermuda population exposed to pond sediment, splenocyte tissue density was markedly lower and lymphocyte proliferation substantially less relative to cohorts exposed to control sediment and to the North American populations. Considerable increases in spleen weight and liver and spleen lesions related to M. chelonae infection were recorded in challenged Bermuda R. marina compared with unchallenged specimens. Overall, immune function in Bermuda R. marina was compromised compared with North American mainland R. marina regardless of treatment but more dramatically in specimens exposed to Bermuda pond sediments. Environ Toxicol Chem 2016;35:2604–2612. © 2016 SETAC. © 2016 SETAC


Fort D.J.,Fort Environmental Laboratories | Meyers J.D.,C.H. Guernsey and Company | Page M.W.,ConocoPhillips | Hercyk N.L.,ConocoPhillips
Water Environment Research | Year: 2013

Total dissolved solids (TDS) management in water has become an increasingly important topic as competition for water supply sources and the intensity of use both increase. Regulatory failure of National Pollutant Discharge Elimination System (NPDES) whole effluent toxicity (WET) tests is one of several potential factors in managing TDS concentrations in effluent. Consequently, WET tests have become a de facto concentration standard that sets the limit for the intensity of water use and the amount of water conservation feasibly obtained for a facility. Conflicting regulations dealing with the application of mixing zones and antidegradation policies can prevent water conservation and actually result in the unintended consequence of causing more water use. The impact of TDS on NPDES-required WET tests, conflicting regulations dealing with the application of mixing zones that are counter-productive to water conservation, alternative practices currently being used, and other means of rectifying this paradox are discussed.


Bacon J.P.,Bermuda Zoological Society | Fort C.E.,Fort Environmental Laboratories | Todhunter B.,Fort Environmental Laboratories | Mathis M.,Fort Environmental Laboratories | Fort D.J.,Fort Environmental Laboratories
Journal of Experimental Zoology Part B: Molecular and Developmental Evolution | Year: 2013

The interactive effects of contaminants and ultraviolet light (UV)-exposure on the incidence and types of abnormalities observed were measured in newly metamorphosed cane toads (Rhinella marina) from four Bermuda ponds contaminated with petrochemicals and metals. Abnormalities were compared in toadlets that were field-collected, reared in predator exclusion cages, reared in laboratory microcosms exposed to control media or corresponding pond media, and reared in laboratory microcosms exposed to UV-light and control media or media from two ponds. Percent abnormal for field-collected, cage-reared, and microcosm-reared toadlets were equivalent per site and ranged between 14% and 63%. All treatments produced similar limb abnormalities but the percentage of hind versus forelimb defects was statistically greater only in field-collected toadlets. UV-exposed control media did not induce abnormalities in larvae exhibiting no maternal effect, and did not alter the types of abnormalities observed in larvae exhibiting a maternal or latent effect. Site media treatments without UV exposure induced significant cephalic and limb abnormalities, proved additive to the observed maternal/latent effect, and produced limb defects predominantly in forelimbs. Concurrent exposure to site media and UV-light induced similar types of abnormalities but a significantly higher percentage of hind limb abnormalities (68-89%) than exposure to site media alone (7-13%). Our results suggest that the types of abnormalities expressed were principally determined by direct and/or transgenerational contaminant exposure, but that UV-light exposure caused limb abnormalities to occur primarily in the hind limbs, mirroring field observations. Our field observations also suggest that ectromelia and brachydactyly in some field-collected specimens may be predator-induced. © 2013 Wiley Periodicals, Inc.


PubMed | Fort Environmental Laboratories
Type: Journal Article | Journal: Toxicological sciences : an official journal of the Society of Toxicology | Year: 2010

Nieuwkoop and Faber stage 51 Xenopus laevis larvae were exposed for 21 days to four different concentrations of triclosan (TCS): <0.2 (control), 0.6, 1.5, 7.2, or 32.3 microg TCS/l. Primary endpoints were survival, hind limb length, body length (whole; snout to vent), developmental stage, wet whole body weight, and thyroid histology. Thyroid hormone (TH) concentrations were determined in whole thyroid and plasma samples from stage-matched exposure day 21 specimens. TH receptor-beta (TRbeta) expression was measured in stage-matched tail fin tissue samples collected at exposure days 0 and 21. Reduced larval growth occurred at exposure day 21 with 1.5 microg/l treatment. Larval developmental stage at exposure day 21 was not significantly different from controls based on observed parameters. Thyroid histology was not affected by TCS, and thyroxine (T4) levels in thyroid glands or plasma were not different from controls. A concentration-dependent increase in TRbeta expression in exposure day 21 larvae was not detected. However, increased expression was found in stage-matched larvae exposed to 1.5 or 7.2 microg TCS/l. Our study indicates that environmentally relevant TCS concentrations do not alter the normal course of thyroid-mediated metamorphosis in this standard anuran model.


PubMed | Fort Environmental Laboratories
Type: Journal Article | Journal: Toxicological sciences : an official journal of the Society of Toxicology | Year: 2011

In a previously reported study, we used a standard metamorphosis anuran model to assess potential effect of the antibacterial agent triclosan (TCS) on normal prometamorphic Xenopus laevis. Results indicated that environmentally relevant TCS concentrations did not alter the normal course of thyroid-mediated metamorphosis in this standard anuran model. However, to examine potential effects of TCS exposure during premetamorphosis and to distinguish between effects on metamorphosis and effects on growth, a longer term TCS exposure study was conducted. Standard Nieuwkoop and Faber (NF) stage 47 X. laevis larvae were exposed for 32 days (ca. NF stage 59-60) via flow-through to four different concentrations of TCS: < 0.2 (control), 0.8, 3.1, 12.5, or 50.0 g TCS/l. Primary endpoints were survival, hind limb length, body length (whole; snout-to-vent), developmental stage, wet whole body weight, thyroid histology, plasma thyroid hormone (TH) concentrations, TH receptor beta (TR), and type II and III deiodinase (DI-2 and DI-3) expression. Endpoints measured to evaluate effects on thyroid-mediated metamorphosis including developmental stage, thyroid histology, TR expression, DI-2 and DI-3 expression, and thyroid gland 3,5,3,5-tetraiodothyronine (T4) and plasma T4 and 3,5,3-triiodothyronine (T3) levels were not affected by TCS exposure. However, increased larval growth based on whole body length (0.78, 12.5, and 50 g TCS/l), snout-vent length (3.1 and 12.5 g TCS/l), and whole body weight (0.8, 12.5, and 50.0 g TCS/l) was observed following 32-day TCS exposure. These results indicated that TCS exposure during pre- and prometamorphosis increased larval growth but did not alter the normal course of metamorphosis in X. laevis. The increased growth associated with TCS exposure was not unexpected and is generally consistent with the presence of reduced bacterial stressors in culture.


PubMed | Fort Environmental Laboratories
Type: Journal Article | Journal: Water environment research : a research publication of the Water Environment Federation | Year: 2013

Total dissolved solids (TDS) management in water has become an increasingly important topic as competition for water supply sources and the intensity of use both increase. Regulatory failure of National Pollutant Discharge Elimination System (NPDES) whole effluent toxicity (WET) tests is one of several potential factors in managing TDS concentrations in effluent. Consequently, WET tests have become a de facto concentration standard that sets the limit for the intensity of water use and the amount of water conservation feasibly obtained for a facility. Conflicting regulations dealing with the application of mixing zones and antidegradation policies can prevent water conservation and actually result in the unintended consequence of causing more water use. The impact of TDS on NPDES-required WET tests, conflicting regulations dealing with the application of mixing zones that are counter-productive to water conservation, alternative practices currently being used, and other means of rectifying this paradox are discussed.


PubMed | Bermuda Zoological Society, Fort Environmental Laboratories and Virginia Polytechnic Institute and State University
Type: Journal Article | Journal: Environmental toxicology and chemistry | Year: 2016

The impacts of contaminated sediment from 2 ponds in Bermuda on immune function in newly metamorphosed cane toads were examined. In the present study, a partial life-cycle experiment exposing Gosner stage 20 cane toad tadpoles to pond sediment and laboratory culture water through metamorphosis and into a juvenile state was performed. A basic immunology battery, including general necropsy, spleen somatic index, spleen white pulp content, splenocyte tissue density, and splenocyte viability, was conducted in newly metamorphosed Rhinella marina exposed to Bermuda freshwater sediment and baseline specimens collected from 2 separate populations in south Texas and south Florida, USA. Immune function was evaluated using a lymphocyte proliferation assay with subset specimens infected with Mycobacterium chelonae. In the Bermuda population exposed to pond sediment, splenocyte tissue density was markedly lower and lymphocyte proliferation substantially less relative to cohorts exposed to control sediment and to the North American populations. Considerable increases in spleen weight and liver and spleen lesions related to M. chelonae infection were recorded in challenged Bermuda R. marina compared with unchallenged specimens. Overall, immune function in Bermuda R. marina was compromised compared with North American mainland R. marina regardless of treatment but more dramatically in specimens exposed to Bermuda pond sediments. Environ Toxicol Chem 2016;35:2604-2612. 2016 SETAC.

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