Diamondback terrapins as indicator species of persistent organic pollutants: Using Barnegat Bay, New Jersey as a case study

Update of the risk assessment of polybrominated diphenyl ethers (PBDEs) in food

The European Commission asked EFSA to update its 2011 risk assessment on polybrominated diphenyl ethers (PBDEs) in food, focusing on 10 congeners: BDE-28, -47, -49, -99, -100, -138, -153, -154, -183 and ‑209. The CONTAM Panel concluded that the neurodevelopmental effects on behaviour and reproductive/developmental effects are the critical effects in rodent studies. For four congeners (BDE-47, -99, -153, -209) the Panel derived Reference Points, i.e. benchmark doses and corresponding lower 95% confidence limits (BMDLs), for endpoint-specific benchmark responses. Since repeated exposure to PBDEs results in accumulation of these chemicals in the body, the Panel estimated the body burden at the BMDL in rodents, and the chronic intake that would lead to the same body burden in humans. For the remaining six congeners no studies were available to identify Reference Points. The Panel concluded that there is scientific basis for inclusion of all 10 congeners in a common assessment group and performed a combined risk assessment. The Panel concluded that the combined margin of exposure (MOET) approach was the most appropriate risk metric and applied a tiered approach to the risk characterisation. Over 84,000 analytical results for the 10 congeners in food were used to estimate the exposure across dietary surveys and age groups of the European population. The most important contributors to the chronic dietary Lower Bound exposure to PBDEs were meat and meat products and fish and seafood. Taking into account the uncertainties affecting the assessment, the Panel concluded that it is likely that current dietary exposure to PBDEs in the European population raises a health concern.

Trace Element Accumulation in Two Turtle Species, Malaclemys terrapin and Chelydra serpentina, in New Jersey, USA

Trace elements in aquatic environments pose a risk to biological communities; this study investigates the total concentrations of arsenic (As), silver (Ag), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), selenium (Se), lead (Pb), and zinc (Zn) within muscle, carapace, liver, and adipose tissues of diamondback terrapins and common snapping turtles in New Jersey. The effects of tissue type, sex, size, and location upon trace element accumulation were studied. The data obtained indicates that within diamondback terrapins and common snapping turtles, trace element accumulations displayed a significant difference among tissue types and sex (p < 0.005). The data indicates that Ag, Cd, Cu, and Hg can accumulate within the liver of diamondback terrapin. Se was found to accumulate in the livers of both diamondback terrapin and common snapping turtles. The highest mean concentrations of Co, Cr, Ni, and Pb were found in the carapace of both turtle species. Sex was found to have an impact on As, Hg, and Zn accumulation within different tissue types of diamondback terrapins. Diamondback terrapin males were found to have higher concentrations of As within the carapace. Diamondback terrapin females possessed higher concentrations of Hg in muscle tissues and Hg and Zn in the carapace. Turtle size and collection location land type and land cover did not display any correlation with trace element bioaccumulation for either species.

Tissue-specific distribution and bioaccumulation of cyclic and linear siloxanes in South Korean crucian carp (carassius carassius)

The occurrence and distribution of cyclic and linear siloxanes were investigated in South Korean river water and sediment, with a special focus on crucian carp tissues, to evaluate the residual status and potential bioaccumulation of siloxanes. The total siloxanes median concentrations observed in this study were 1495 ng/L in river water, 39.2 ng/g-dry weight [dw] in sediment, and 41.7 ng/g-wet weight [ww] in crucian carp muscle. Cyclic siloxanes (D3-D6) were predominant in all matrices, and D5 (mean: > 81%) was more abundant in biota tissues than in river water (30%) and sediment (26%) samples. Specifically, positive correlations between D5 concentrations and crucian carp sizes (p < 0.01, Spearman) as well as the relatively high estimated biota-sediment accumulation factor value of D5 (D5: 2.31), suggest the high bioaccumulative property of D5 in biota. However, no bioaccumulation potentials were observed for D3, D4, D6, and L3-L17 in this field-scale study. The distributions of major linear siloxanes (L7-L14) in crucian carp gills (17%) and gonads (21%) were higher than in other tissues (brain, 9.6%; liver, 2.6%; muscle, 1.5%). Moreover, relatively high tissue/plasma ratios were observed for linear siloxanes (L7-L10: 1.79-2.12) compared to cyclic siloxanes (D4-D6: 0.829-1.18) (p < 0.01, Mann Whitney U test), which indicated the higher transportability of linear siloxanes to fish tissues than cyclic siloxanes.

Multiresidue analysis of 85 persistent organic pollutants in small human serum samples by modified QuEChERS preparation with different ionization sources in mass spectrometry

In this study, a multiresidue analytical method was developed, validated, and applied for quantifying 85 persistent organic pollutants (POPs), including 38 polychlorinated biphenyls (PCBs), 23 polybrominated diphenyl ethers (PBDEs), and 24 organochlorine pesticides (OCPs) from 200 μL of human serum. A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method was applied to minimize the required sample amount and optimize various conditions including the extraction solvent and the number of extractions. The extraction efficiency was optimized using double extraction with an ethyl acetate/hexane/acetone mixture. Gas chromatography coupled with triple-quadrupole mass spectrometry was used for analysis, and two different ionization sources, electron impact ionization (EI) and atmospheric pressure chemical ionization (APCI), were used to compare their sensitivity. The APCI source employed soft ionization at atmospheric pressure, producing abundant molecular ion formation with minimal fragmentation, in contrast to extensive fragmentation caused by EI. Of the 85 POPs analyzed, 59 target compounds (69.4%) showed lower limits of detection that were two- to fifty-fold lower in APCI than those determined using EI. The developed method was validated for its detection limit (0.5-10 pg/mL for PCBs, 2-20 pg/mL for PBDEs, and 2-40 pg/mL for OCPs), precision (0.8%-34.3% of coefficient of variation), recovery (49.6%-77.1%), matrix effect (46.7%-156.9%), and accuracy (81.2%-113.1% for PCBs, 85.8%-112.2% for PBDEs, and 55.2%-113.9% for OCPs). Its linearity was R² > 0.99 for 84 compounds, and 96% average accuracy (for APCI) was obtained using the National Institute of Standards and Technology (NIST) standard reference materials (NIST 1957 and 1958). These ionization methods were compared by analyzing 25 real human serum samples. The observed species were 1.1-24.6 pg/mL of 28 PCBs, 2.5 pg/mL of BDE-47, and 6.5-195.1 pg/mL of 6 organochlorine pesticides (median concentration for each species), and only 11 compounds were detected with APCI owing to its enhanced sensitivity.

Short- and medium-chain chlorinated paraffins in aquatic organisms from an e-waste site: Biomagnification and maternal transfer

Chlorinated paraffins (CPs) are globally pervasive contaminants that are toxic to humans and wildlife. Inconsistent biomagnification behaviors in different food chains have been reported, and very few studies have been conducted to investigate the maternal transfer of CPs in ovoviviparous species. This study investigated the biomagnification of short- and medium-chain chlorinated paraffins (S/MCCPs) in two aquatic food chains, as well as maternal transfer of S/MCCPs in watersnakes collected from an e-waste polluted pond in southern China. The concentrations of SCCPs and MCCPs varied from 1.2 to 250 μg/g lipid weight (lw) and from 2.3 to 200 μg/g lw in the collected organisms. The SCCP homologue profiles in prey (fish and prawn) differed from those in predators (watersnake and waterbird egg), while MCCP homologue group patterns were homogeneous. All maternal transfer concentration ratios (egg to muscle) of S/MCCPs in the watersnakes were lower than 1 and negatively correlated with the octanol-water partition coefficients (log K_OW), different from the maternal transfer of halogenated aromatic pollutants in the watersnake. Biomagnification factors (BMFs) of S/MCCPs for fish-watersnake muscle food chain were larger than 1, while BMFs for the fish-waterbird egg food chain were less than 1. However, when watersnake egg was used to calculate BMF, no biomagnification was found. BMFs in the two food chains showed significant positive linear correlations with chlorine atoms, but no significant correlation with carbon atom numbers, which suggested that a congener-group-specific elimination and excretion process for S/MCCPs exist.

Perfluoroalkyl substances in diamondback terrapins (Malaclemys terrapin) in coastal South Carolina

This study focused on an estuarine wildlife species exhibiting high site fidelity and ubiquitous distribution in coastal environments along the Atlantic and Gulf coasts of the United States to monitor per- and polyfluoroalkyl substances (PFAS). A total of 75 diamondback terrapin (Malaclemys terrapin) plasma samples were collected from five creeks associated with Kiawah (Oyster Creek, Fiddler Creek, Sandy Creek, Gnat Creek) and Edisto (Townsend Creek) islands in Charleston County, South Carolina and investigated for 15 legacy PFAS. Of those, PFHxS was the only PFAS found in all terrapin plasma samples. Four additional PFAS were routinely detected (greater than 90% of the samples) and were included in statistical analyses: PFOS, PFNA, PFDA, and PFUnA. Sex-differences were observed for two creeks with male plasma containing higher PFAS than female plasma (PFHxS at Townsend Creek, PFOS at Oyster Creek). Sex-specific site differences in PFAS concentrations were observed primarily for males, suggesting male terrapins may be more sensitive indicators of localized contaminant profiles than females. Three PFAS were observed to have negative correlations with body mass: PFOS in males (p = 0.045, tau = -0.220), PFNA in males (p = 0.016, tau = -0.269), and PFHxS in both males (p = 0.007, tau = -0.302) and females (p = 0.001, tau = -0.379). No relationships for body mass and PFDA and PFUnA were observed.

Mercury Contamination in Diamondback Terrapins in New Jersey

Mercury contamination in consumed foods poses a significant threat to human health globally. The consumption of mercury-contaminated turtle meat is of special concern due to mercury's capability to bioaccumulate and biomagnify in organisms. Turtles are long-lived predators, allowing for a high degree of bioaccumulation and biomagnification of contaminants. In the U.S., diamondback terrapins (Malaclemys terrapin) are legally harvested in several states throughout their range. Harvested turtles are usually sold to both local and global markets mainly for human consumption, which results in a human consumption threat. The objective of this study was to analyze mercury concentrations to determine if the consumption of terrapins poses a threat to human health. Diamondback terrapins were collected from two study sites: Cape May and Hackensack Meadowlands, New Jersey, relatively pristine and contaminated estuaries, respectively. Turtle carapace, blood, and muscle samples were analyzed for total mercury concentrations. Results showed significant difference between study sites and females' and males' blood mercury concentrations. Similarly, results showed blood mercury correlated with carapace length. Results also showed that 50% of Cape May muscle samples and 72.7% Meadowlands muscles samples surpassed the New Jersey sensitive threshold of 0.18 ppm. Furthermore, 27.3% of Cape May muscle samples and 45.5% of Meadowlands muscles samples surpassed the U.S. Environmental Protection Agency's mercury threshold of 0.3 ppm for seafood consumption for the general public. Overall, the harvest of terrapins could pose a threat to consumers, and terrapins should be monitored closely or possibly banned for human consumption, especially in areas with known contamination history.

Large-scale variation in density of an aquatic ecosystem indicator species

Monitoring indicator species is a pragmatic approach to natural resource assessments, especially when the link between the indicator species and ecosystem state is well justified. However, conducting ecosystem assessments over representative spatial scales that are insensitive to local heterogeneity is challenging. We examine the link between polychlorinated biphenyl (PCB) contamination and population density of an aquatic habitat specialist over a large spatial scale using non-invasive genetic spatial capture-recapture. Using American mink (Neovison vison), a predatory mammal and an indicator of aquatic ecosystems, we compared estimates of density in two major river systems, one with extremely high levels of PCB contamination (Hudson River), and a hydrologically independent river with lower PCB levels (Mohawk River). Our work supports the hypothesis that mink densities are substantially (1.64-1.67 times) lower in the contaminated river system. We demonstrate the value of coupling the indicator species concept with well-conceived and spatially representative monitoring protocols. PCBs have demonstrable detrimental effects on aquatic ecosystems, including mink, and these effects are likely to be profound and long-lasting, manifesting as population-level impacts. Through integrating non-invasive data collection, genetic analysis, and spatial capture-recapture methods, we present a monitoring framework for generating robust density estimates across large spatial scales.

The Risk of Polychlorinated Biphenyls Facilitating Tumors in Hawaiian Green Sea Turtles (Chelonia mydas)

The Hawaiian green turtle (Chelonia mydas) is on the list of threatened species protected under the U.S. Endangered Species Act in 1978 in large part due to a severe tumor-forming disease named fibropapillomatosis. Chemical pollution is a prime suspect threatening the survival of C. mydas. In this study, PCBs concentrations were determined in 43 C. mydas plasma samples archived on Tern Island. The total PCBs concentration in male C. mydas (mean 1.10 ng/mL) was two times more than that of females (mean 0.43 ng/mL). The relationship between straight carapace length and PCBs concentration in females has also been studied, which was negatively related. To figure out the possible existence of correlations between PCBs and tumor status, we measured the PCBs concentration in turtles with no tumor, moderate or severe tumor affliction. PCBs concentration of two afflicted groups was much higher than the healthy group, suggesting that PCBs may play a role in fibropapillomatosis in Hawaiian green turtle.

Triclosan exposure, transformation, and human health effects

Triclosan (TCS) is an antimicrobial used so ubiquitously that 75% of the US population is likely exposed to this compound via consumer goods and personal care products. In September 2016, TCS was banned from soap products following the risk assessment by the US Food and Drug Administration (FDA). However, TCS still remains, at high concentrations, in other personal care products such as toothpaste, mouthwash, hand sanitizer, and surgical soaps. TCS is readily absorbed into human skin and oral mucosa and found in various human tissues and fluids. The aim of this review was to describe TCS exposure routes and levels as well as metabolism and transformation processes. The burgeoning literature on human health effects associated with TCS exposure, such as reproductive problems, was also summarized.

Ecotoxicological assessment of diamondback terrapin (Malaclemys terrapin) pond habitat, prey and eggs in Bermuda

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.

Developmental exposure to bisphenol A (BPA) alters sexual differentiation in painted turtles (Chrysemys picta)

Environmental chemicals can disrupt endocrine signaling and adversely impact sexual differentiation in wildlife. Bisphenol A (BPA) is an estrogenic chemical commonly found in a variety of habitats. In this study, we used painted turtles (Chrysemys picta), which have temperature-dependent sex determination (TSD), as an animal model for ontogenetic endocrine disruption by BPA. We hypothesized that BPA would override TSD and disrupt sexual development. We incubated farm-raised turtle eggs at the male-producing temperature (26°C), randomly assigned individuals to treatment groups: control, vehicle control, 17β-estradiol (E2, 20ng/g-egg) or 0.01, 1.0, 100μgBPA/g-egg and harvested tissues at hatch. Typical female gonads were present in 89% of the E2-treated "males", but in none of the control males (n=35). Gonads of BPA-exposed turtles had varying amounts of ovarian-like cortical (OLC) tissue and disorganized testicular tubules in the medulla. Although the percentage of males with OLCs increased with BPA dose (BPA-low=30%, BPA-medium=33%, BPA-high=39%), this difference was not significant (p=0.85). In all three BPA treatments, SOX9 patterns revealed disorganized medullary testicular tubules and β-catenin expression in a thickened cortex. Liver vitellogenin, a female-specific liver protein commonly used as an exposure biomarker, was not induced by any of the treatments. Notably, these results suggest that developmental exposure to BPA disrupts sexual differentiation in painted turtles. Further examination is necessary to determine the underlying mechanisms of sex reversal in reptiles and how these translate to EDC exposure in wild populations.

Persistent halogenated compounds in captive Chinese alligators (Alligator sinensis) from China

While a number of studies have reported residual levels of persistent halogenated compounds (PHCs) in crocodilia, there is still a dearth of information on the Chinese alligator, a critically endangered crocodilian species. In the present study, several PHCs, including polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and dichlorodiphenyltrichloroethane and its metabolites (DDTs), were detected in the adult tissues, neonates, and eggs of captive Chinese alligators from China. The concentrations of ΣPBDEs, ΣPCBs, and ΣDDTs in Chinese alligators ranged from 0.11 to 16.1, 1.12 to 22.2, and 6.03 to 1020ngg(-1) wet weight, respectively, with higher levels of ΣPCBs and ΣDDTs in the neonates and eggs than in muscle tissues. The ΣDDT residues in the studied Chinese alligators were at the high end of reported ranges from crocodilia around the world, and some results exceeded levels known to cause a female-biased sex ratio in crocodilians.

Artificial nesting habitats as a conservation strategy for turtle populations experiencing global change

Diamondback terrapins (Malaclemys terrapin) inhabit estuaries in eastern USA and may tolerate salinity of sea-water for short durations. Many North American estuaries are adversely affected by anthropogenic impacts, such as pollution, dredging and invasion by non-native plants. Many nesting areas have been altered or destroyed, causing terrapins to nest on roadsides and artificial islands made of dredged substrate from bottom sediments. Shading by non-native plants may suppress development and reduce survival of embryos. In Barnegat Bay, New Jersey, USA, there is a mosaic of natural and degraded terrapin nesting habitats. We investigated the effects of dredge soil and shade on the hatching success of diamondback terrapins to determine whether nesting habitat could be increased by using dredged bottom sediments. In year 1, unshaded nests in natural loamy-sand had the highest hatching success (55.2%), while nests in dredge soil produced no hatchlings. In year 2, nests in unshaded loamy-sand had a hatching success of 85.3%, whereas those in dredge soil, aged 1 year, had a hatching success of 59.4%. Dredge soil improved as an incubation substrate after aging 1 year by the washout of salt. Nest temperatures were generally cool and produced mostly male hatchlings. Uncontaminated dredge soil may provide suitable nesting substrates for diamondback terrapins if used after one year, and may be particularly beneficial if used for constructing islands that provide new nesting sites with reduced access of mammalian predators.

Forty-seven days of decay does not change persistent organic pollutant levels in loggerhead sea turtle eggs

Reptile and bird eggs are priority samples for specimen banking programs that assess spatial and temporal trends of environmental contaminants. From endangered species, such as sea turtles, nonlethal sampling is required (e.g., unhatched eggs collected postemergence). Previous contaminant monitoring studies have used unhatched sea turtle eggs, but no study has tested whether their concentrations represent levels found in fresh eggs (e.g., eggs collected within 24 h of oviposition). The author analyzed three fresh eggs from different nest depths and up to three unhatched eggs from 10 loggerhead sea turtle (Caretta caretta) nests in South Carolina, USA, for a suite of persistent organic pollutants (POPs). Lipid-normalized POP concentrations were not significantly different (p > 0.05) between fresh and unhatched eggs or among different depths from the same nest. The POP concentrations in loggerhead eggs from South Carolina were higher than previously measured concentrations in eggs from Florida and slightly lower than concentrations in eggs from North Carolina. This pattern agrees with previously observed trends of increasing POP concentrations in loggerhead turtles inhabiting northern latitudes along the U.S. East Coast. Contaminant profiles are discussed, including a higher chlorinated pattern of polychlorinated biphenyls possibly associated with a Superfund site in nearby Brunswick, Georgia, USA, and unusual polybrominated diphenylether patterns seen in this and previous sea turtle studies. Concentrations correlated with one of eight measurements of reproductive success; levels were negatively correlated with egg mass (p < 0.05), which may have implications for hatchling fitness. The present study suggests that unhatched eggs can be used for POP-monitoring projects.

Slow O-demethylation of methyl triclosan to triclosan, which is rapidly glucuronidated and sulfonated in channel catfish liver and intestine

The antibacterial personal care product triclosan is discharged in municipal waste, and converted in part by bacteria in sewage sludge and soil to its more lipid-soluble methyl ether, methyl triclosan. Triclosan and methyl triclosan have been detected in water, sediment, fish and invertebrates near sewage treatment facilities. Understanding the biotransformation of methyl triclosan and triclosan in a model food fish, the channel catfish, will be of value in assessing the likelihood that these compounds will bioaccumulate in exposed fish, and therefore potentially pass up the food chain. We hypothesize that cytochrome P450 will catalyze the O-demethylation of methyl triclosan to yield triclosan, which is likely to undergo glucuronidation or sulfonation of the phenolic hydroxyl group. Conversion of methyl triclosan to triclosan was measured by LC/MS/MS following aerobic incubation of varying concentrations of methyl triclosan with NADPH and hepatic and intestinal microsomes from untreated, 3-methylcholanthrene-treated (10 mg/kg, i.p.) or PCB-126-treated (0.1 mg/kg, i.p.) channel catfish (n=4 per treatment group). The K(m) values for methyl triclosan were similar for untreated, 3-methylcholanthrene-treated and PCB-126-treated catfish liver microsomes, ranging from 80 to 250 μM. V(max) values for O-demethylation ranged from 30 to 150 pmol/min/mg protein, with no significant differences between controls, PCB-126-treated or 3-methylcholanthrene-treated fish, suggesting that methyl triclosan O-demethylation was not a CYP1-catalyzed reaction. Methyl triclosan O-demethylation activities in intestinal microsomes were similar to or lower than those found with liver microsomes. The calculated rate of O-demethylation of methyl triclosan in catfish liver at 1 μM, a concentration reported in exposed fish, and 21°C, an early summer water temperature, is 0.10 pmol/min/mg protein. This slow rate of metabolism suggests that upon continued exposure, methyl triclosan may bioaccumulate in the channel catfish. Triclosan itself, however, was readily glucuronidated by hepatic and intestinal microsomes and sulfonated by hepatic and intestinal cytosol. Triclosan glucuronidation followed Michaelis-Menten kinetics when rates were measured across a concentration range of 5-1000 μM, whereas triclosan sulfonation exhibited substrate inhibition at concentrations above 10-20 μM in both intestinal and hepatic cytosol. Based on the enzyme kinetic constants measured in hepatic and intestinal fractions at 21°C, triclosan at 1 μM could be glucuronidated at rates of 23 and 3.2 pmol/min/mg protein respectively in liver and intestine, and sulfonated at rates of 277 (liver) and 938 (intestine) pmol/min/mg protein. These rates are much higher than the rates of demethylation of methyl triclosan, and suggest that triclosan would be rapidly cleared and unlikely to bioaccumulate in catfish tissues.

Geographical variation of persistent organic pollutants in eggs of threatened loggerhead sea turtles (Caretta caretta) from southeastern United States

Persistent organic pollutants (POPs) are recognized manmade threats to sea turtle populations, but substantial uncertainty exists surrounding their exposure to contaminants and their sensitivity to toxic effects. This uncertainty creates difficulty for conservation managers to make informed decisions for the recovery of these threatened species. To provide baseline concentrations and spatial comparisons, we measured a large suite of POPs in loggerhead sea turtle (Caretta caretta) egg yolk samples collected from 44 nests in three distinct U.S. locations: North Carolina (NC), eastern Florida (E FL), and western Florida (W FL). The POPs included polychlorinated biphenyls (PCBs), organochlorine pesticides such as dichlorodiphenyltrichloroethanes (DDTs), chlordanes, mirex, dieldin, hexachlorocyclohexanes (HCHs), hexachlorobenzene, and toxaphene congeners, as well as polybrominated diphenyl ether congeners (PBDEs). Persistent organic pollutant concentrations were lowest in W FL, intermediate in E FL, and highest in NC egg samples, with several statistically significant spatial differences. This increasing gradient along the southeast coast around the Florida peninsula to North Carolina was explained partly by the foraging site selection of the nesting females. Data from previous tracking studies show that NC nesting females feed primarily along the U.S. eastern coast, whereas W FL nesting females forage in the Gulf of Mexico and Caribbean Sea. The E FL nesting females forage in areas that overlap these two. The foraging site selection also results in exposure to different patterns of POPs. An unusual PBDE pattern was seen in the NC samples, with nearly equal contributions of PBDE congeners 47, 100, and 154. These findings are important to managers assessing threats among different stocks or subpopulations of this threatened species.

Monitoring persistent organic pollutants in leatherback turtles (Dermochelys coriacea) confirms maternal transfer

To assess threats to endangered species, it is critical to establish baselines for contaminant concentrations that may have detrimental consequences to individuals or populations. We measured contaminants in blubber and fat from dead leatherback turtles and established baselines in blood and eggs in nesting turtles. In fat, blubber, blood and eggs, the predominant PCBs were 153+132, 187+182, 138+163, 118, and 180+193. Total PCBs, 4,4'-DDE, total PBDEs and total chlordanes were significantly and positively correlated between blood and eggs, suggesting maternal transfer. Significant positive relationships also existed between fat and blubber in stranded leatherbacks. Less lipophilic PCBs appeared to more readily transfer from females to their eggs. PBDE profiles in the four tissues were similar to other wildlife populations but different from some turtle studies. Concentrations were lower than those shown to have acute toxic effects in other aquatic reptiles, but may have sub-lethal effects on hatchling body condition and health.

Persistent organic pollutants in blood plasma of satellite-tracked adult male loggerhead sea turtles (Caretta caretta)

Risks from persistent organic pollutants (POPs) remain largely a mystery for threatened loggerhead sea turtles (Caretta caretta). The present study examines regional-scale POP differences in blood plasma from adult male C. caretta based on movement patterns. Turtles were captured near Port Canaveral, Florida, USA, in April of 2006 and 2007 and fitted with satellite transmitters as part of a National Marine Fisheries Service-funded project. Residents (n = 9) remained near the capture site, whereas transients (n = 10) migrated northward, becoming established in areas largely from south of Pamlico Sound, North Carolina, to north of Cape May, New Jersey, USA. Blood was sampled from the dorsocervical sinus of each turtle and analyzed using gas chromatography-mass spectrometry for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and toxaphenes. Blood plasma concentrations of OCPs and total PBDEs were elevated in transients (p < 0.05) and in some cases were correlated with turtle size. Migratory adults showed an atypical PBDE congener profile relative to other published studies on wildlife, with PBDE 154 being the dominant congener. Additionally, PCB congener patterns differed between groups, with total PCBs slightly elevated in transients. This supports the idea that foraging location can influence exposure to, and patterns of, POPs in highly mobile species such as C. caretta. Understanding patterns of contamination informs wildlife managers about possible health risks to certain subpopulations. The present study is the first to examine POPs in the rarely studied adult male sea turtle and to couple contaminant measurements with satellite tracking.