Cryptic lineages and standing genetic variation across independent cane toad introductions.

Widespread introduced species can be leveraged to investigate the genetic, ecological and adaptive processes underlying rapid evolution and range expansion, particularly the contributions of genetic diversity to adaptation. Rhinella marina, the cane toad, has been a focus of invasion biology for decades in Australia. However, their introduction history in North America is less clear. Here, we investigated the roles of introduction history and genetic diversity in establishment success of cane toads across their introduced range. We used reduced representation sequencing (ddRAD) to obtain 34,000 SNPs from 247 toads in native (French Guiana, Guyana, Ecuador, Panama, Texas) and introduced (Bermuda, southern Florida, northern Florida, Hawai'i, Puerto Rico) populations. Unlike all other cane toad introductions, we found that Florida populations were more closely related to native Central American lineages (R. horribilis), than to native Southern American lineages (R. marina). Furthermore, we found high levels of diversity and population structure in the native range, corroborating suggestions that R. marina is a species complex. We also found that introduced populations exhibit only slightly lower genetic diversity than native populations. Together with demographic analyses, this indicates founding populations of toads in Florida were larger than previously reported. Lastly, within R. marina, only one of 245 putatively adaptive SNPs showed fixed differences between native and introduced ranges, suggesting that putative selection in these introduced populations is based upon existing genetic variation. Our findings highlight the importance of genetic sequencing in understanding biological introductions and hint at the role of standing genetic variation in range expansion.

Splenic immunotoxicity in developing cane toads (Rhinella marina) from Bermuda.

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.

Application of endocrine disruptor screening program fish short-term reproduction assay: Reproduction and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus) exposed to Bermuda pond sediment.

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 21 d. 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 3ß/17ß -hydroxysteroid dehydrogenase [3ß/17ß-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 3ß/17ß-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.

Effects of multiple chemical, physical, and biological stressors on the incidence and types of abnormalities observed in Bermuda's cane toads (Rhinella marina).

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.

Safety of exenatide once weekly for 52 weeks in Japanese patients with type 2 diabetes mellitus.

AIMS/INTRODUCTION: An initial 26-week, randomized, open-label study compared the efficacy and safety of exenatide 10 mcg twice daily with exenatide 2 mg once weekly in Asian patients with type 2 diabetes who experienced inadequate glycemic control with oral antidiabetes medications. The aim of this study was to evaluate the safety of exenatide once weekly in Japanese patients, a subset of the initial patient population, who continued into this extension study for an additional 26 weeks of therapy on exenatide once weekly, followed by 10 weeks without exenatide once weekly. MATERIALS AND METHODS: Japanese patients initially assigned to exenatide twice daily (n = 62) switched to exenatide once weekly for the extended 26 weeks, and patients initially assigned to exenatide once weekly (n = 74) continued on this regimen for the remainder of the study (total treatment of 52 weeks). RESULTS: A total of 68% of patients reported one or more treatment-emergent adverse events during the extension period; the most common of these were nasopharyngitis (14%) and vomiting (6%). No major hypoglycemic episodes were reported. Improvements in glycated hemoglobin, fasting plasma glucose and postprandial glucose were maintained over 52 weeks of treatment. At week 52, bodyweight remained reduced from baseline. CONCLUSIONS: Exenatide once weekly added to oral antidiabetes medication was well tolerated in Japanese patients with type 2 diabetes, and was associated with glycemic control and weight loss through to 52 weeks, supporting the use of exenatide once weekly as an adjunctive treatment for type 2 diabetes in this patient population. The initial 26-week portion of this trial was registered with ClinicalTrials.gov (no. NCT00917267).

Safety and efficacy of once-weekly exenatide compared with insulin glargine titrated to target in patients with type 2 diabetes over 84 weeks.

OBJECTIVE: We recently reported that after 26 weeks, exenatide once weekly (EQW) resulted in superior A1C reduction, reduced hypoglycemia, and progressive weight loss compared with daily insulin glargine (IG) in patients with type 2 diabetes who were taking metformin alone or with sulfonylurea. This 84-week extension study assessed the long-term safety and efficacy of EQW versus IG. RESEARCH DESIGN AND METHODS: This multicenter, open-label, randomized, two-arm, parallel trial assessed change in A1C, proportions of patients achieving A1C <7.0 and ≤6.5%, body weight, incidence of hypoglycemia, and overall safety. RESULTS: Of 415 patients who completed 26 weeks, 390 (194 EQW and 196 IG patients) entered the extension study. At 84 weeks, A1C decreased from baseline (8.3%) by -1.2% for EQW vs. -1.0% for IG (P = 0.029). The proportions of patients who achieved end point A1C targets <7.0 and ≤6.5% were 44.6% for EQW patients vs. 36.8% for IG patients (P = 0.084) and 31.3% for EQW patients vs. 20.2% for IG patients (P = 0.009), respectively. Patients taking EQW lost 2.1 kg of body weight, whereas those taking IG gained 2.4 kg (P < 0.001). Among patients taking metformin plus sulfonylurea, the incidence of minor hypoglycemia was 24% for EQW patients vs. 54% for IG patients (P < 0.001); among patients taking metformin alone, it was 8% for EQW patients vs. 32% for IG patients (P < 0.001). Among adverse events occurring in ≥5% of patients, diarrhea and nausea occurred more frequently (P < 0.05) in the EQW group than in the IG group (12 vs. 6% and 15 vs. 1%, respectively). CONCLUSIONS: After 84 weeks, patients treated with EQW continued to experience better glycemic control with sustained overall weight loss and a lower risk of hypoglycemia than patients treated with IG.

Exenatide bid observational study (ExOS): baseline population characteristics of a prospective research study to evaluate the clinical effectiveness of exenatide bid use in patients with type 2 diabetes in a real-world setting.

OBJECTIVES: To describe the Exenatide Observational Study (ExOS) and patients initiating exenatide therapy in a real-world clinical practice setting. METHODS: ExOS is a prospective, single-arm, multicenter, observational study to assess the effectiveness of up to 24 months of exenatide therapy in patients with type 2 diabetes (T2D). Patients with T2D ≥18 years of age, who initiated exenatide therapy, were eligible. The primary effectiveness endpoint is achieving or maintaining hemoglobin A1C of ≤7.0%, or an absolute drop of 0.5% from baseline. Secondary objective measures evaluate the absolute and percentage changes from baseline for a variety of clinical measures (lipid markers, weight, BMI, etc.) and quality of life (QOL) is assessed using the Impact of Weight on Quality of Life (IWQOL)-Lite. RESULTS: On average, the baseline population (n = 531) was aged 55 years, predominantly female (62%), white (79%), educated, obese (mean BMI 39 kg/m(2)), with mean HbA(1c), blood pressure, total cholesterol, and triglyceride values of 8.0%, 129/76 mmHg, 174 mg/dL, and 197 mg/dL, respectively. A total of 28% entered the study with HbA(1c) ≤7.0% and 67% were being treated with oral antihyperglycemic drug(s) (OAD) only [1 (28.4%), 2 (28.4%), >2 (10.2%)], or some form of insulin ±OADs (19%), and ≥50% were on a cholesterol-lowering drug(s) ± antihypertensive medication(s). The single-arm design of this study is a limitation; however, the overall objective of the ongoing study is to observe patients on exenatide therapy over time, comparing their status at endpoint to baseline, rather than to make comparisons among different drug therapies. CONCLUSIONS: Patients treated with exenatide tended to be obese, middle-aged women on various combinations of OADs and/or insulin who often had hypertension and/or dyslipidemia. Further planned analyses will provide the largest sample of prospective data on outcomes of exenatide therapy for up to 24 months in this usual-care population.

Randomized, open-label, parallel-group evaluations of basal-bolus therapy versus insulin lispro premixed therapy in patients with type 2 diabetes mellitus failing to achieve control with starter insulin treatment and continuing oral antihyperglycemic drugs: a noninferiority intensification substudy of the DURABLE trial.

BACKGROUND: Insulin glargine and lispro mix 75/25 (75% insulin lispro protamine suspension and 25% insulin lispro injection [LM75/25]) represent 2 common starter insulin regimen classes: basal and premixed. After initiation of starter insulin therapy, if patients with type 2 diabetes mellitus (DM) are unable to achieve a glycosylated hemoglobin (HbA1c) level <7.0%, insulin intensification may be indicated. The DURABLE (Assessing Durability of Basal Versus Lispro Mix 75/25 Insulin Efficacy) trial was designed to compare initiating insulin therapy with analogue basal insulin versus premixed analogue insulin in patients unable to achieve good glycemic control while taking multiple oral antihyperglycemic drugs (OADs). OBJECTIVE: To provide objective information about insulin intensification, the DURABLE trial also included a substudy evaluating a systematic approach to advancing insulin therapy in those patients who did not achieve glycemic control with their initial insulin regimen. This substudy, the results of which are reported here, tested the hypothesis that advancing insulin therapy with premixed insulin is noninferior to basal-bolus therapy (BBT) in patients with type 2 DM unable to achieve an HbA1c level < or = 7.0% after 6 months of starter insulin therapy. METHODS: In the main DURABLE study, 2091 patients (age range, 30-80 years) with type 2 DM and HbA1c values >7.0% receiving > or = 2 OADs were randomized to receive insulin glargine (n = 1046) or LM75/25 (n = 1045), both in combination with prestudy OADs. After 6 months, patients with HbA1c levels >7.0% could enter this intensification substudy; OADs except sulfonylureas were continued. Patients originally receiving insulin glargine were enrolled in intensification arm A and were randomized to receive BBT (insulin glargine once daily plus mealtime insulin lispro TID) or LM75/25 BID. Patients originally receiving LM75/25 were enrolled in intensification arm B and randomized to receive BBT or mealtime 50% insulin lispro protamine suspension and 50% insulin lispro injection (LM50/50) TID. Insulin doses were adjusted based on preprandial plasma glucose levels. The primary end point was noninferiority of premixed therapy versus BBT with respect to end-point HbA1c. Secondary end points included change in HbA1c and weight, percentage of patients reaching HbA1c target levels, total daily insulin dose, and rates of hypoglycemia. The safety profile was also assessed. RESULTS: Of the 475 patients in the insulin glargine + OAD arm of the main study who had HbA1c levels >7.0% at 6 months, 399 (84%) entered intensification arm A. The mean age was 57 years, 53% of the patients were male, and mean (SD) HbA1c was 8.0% (1.0%) at baseline. Of those patients, 199 were randomly assigned to receive BBT and 200 were assigned to receive LM75/25. Of the 411 patients in the LM75/25 + OAD arm of the main study who had an HbA1c level >7.0% at 6 months, 345 (84%) entered intensification arm B. The mean age was 55 years, 51% of the patients were male, and mean (SD) HbA1c was 8.0% (0.9%) at baseline. Of those patients, 171 were randomly assigned to receive BBT and 174 were assigned to receive LM50/50. At end point, noninferiority of LM75/25 or LM50/50 to BBT was supported, with a 95% CI of -0.10 to 0.37 and -0.25 to 0.25, respectively. At 6 months, HbA1c did not differ significantly from baseline in any group. Regardless of treatment group, <20% of patients achieved an HbA1c level <7.0%. There were no significant differences between groups in total daily insulin dose, weight gain, incidence or rate of hypoglycemia, or incidence of serious adverse events. CONCLUSIONS: No group had significant improvement from baseline in HbA1c. Our study results suggest that premixed therapy, dosed 2 times per day (LM75/25) or 3 times per day (LM50/50), was noninferior to BBT (4 injections/d) in this population of adult patients with type 2 DM previously uncontrolled with OADs plus basal insulin or twice-daily premixed insulin. Clinical-Trials.gov identifier: NCT00279201.

Impact of race/ethnicity on the efficacy and safety of commonly used insulin regimens: a post hoc analysis of clinical trials in type 2 diabetes mellitus.

OBJECTIVE: To explore the impact of race/ethnicity on the efficacy and safety of commonly used insulin regimens in patients with type 2 diabetes mellitus. METHODS: In this post hoc analysis, pooled data from 11 multinational clinical trials involving 1455 patients with type 2 diabetes were used to compare specific insulin treatments in Latino/Hispanic, Asian, African-descent, and Caucasian patients. Insulin treatments included once daily insulin glargine or neutral protamine Hagedorn (BASAL), insulin lispro mix 75/25 twice daily (LMBID), or insulin lispro mix 50/50 three times daily (LMTID). RESULTS: Race/ethnicity was associated with significant outcome differences for each of the insulin regimens. BASAL therapy was associated with greater improvement in several measures of glycemic control among Latino/Hispanic patients compared with Caucasian patients (lower end point hemoglobin A1c, greater reduction in hemoglobin A1c from baseline, and a larger proportion of patients achieving hemoglobin A1c level <7%). In contrast, LMBID therapy was associated with higher end point hemoglobin A1c and a smaller decrease in hemoglobin A1c from baseline in Latino/Hispanic and Asian patients than in Caucasian patients. Furthermore, fewer Asian patients attained a hemoglobin A1c level <7% than did Caucasians patients. For LMTID therapy, hemoglobin A1c outcomes were comparable across patient groups. Fasting blood glucose and glycemic excursions varied among racial/ethnic groups for the 3 insulin regimens. Weight change was comparable among racial/ethnic groups in each insulin regimen. During treatment with LMTID, Asian patients experienced higher incidence and rate of severe hypoglycemia than Caucasian patients. CONCLUSIONS: Latino/Hispanic, Asian, and African-descent patients with type 2 diabetes show different metabolic responses to insulin therapy, dependent in part on insulin type and regimen intensity.

DURAbility of basal versus lispro mix 75/25 insulin efficacy (DURABLE) trial 24-week results: safety and efficacy of insulin lispro mix 75/25 versus insulin glargine added to oral antihyperglycemic drugs in patients with type 2 diabetes.

OBJECTIVE: To compare the ability of two starter insulin regimens to achieve glycemic control in a large, ethnically diverse population with type 2 diabetes. RESEARCH DESIGN AND METHODS: During the initiation phase of the DURABLE trial, patients were randomized to a twice-daily lispro mix 75/25 (LM75/25; 75% lispro protamine suspension, 25% lispro) (n = 1,045) or daily glargine (GL) (n = 1,046) with continuation of prestudy oral antihyperglycemic drugs. RESULTS: Baseline A1C was similar (LM75/25: 9.1 +/- 1.3%; GL: 9.0 +/- 1.2%; P = 0.414). At 24 weeks, LM75/25 patients had lower A1C than GL patients (7.2 +/- 1.1 vs. 7.3 +/- 1.1%, P = 0.005), greater A1C reduction (-1.8 +/- 1.3 vs. -1.7 +/- 1.3%, P = 0.005), and higher percentage reaching A1C target <7.0% (47.5 vs. 40.3%, P < 0.001). LM75/25 was associated with higher insulin dose (0.47 +/- 0.23 vs. 0.40 +/- 0.23 units x kg(-1) x day(-1), P < 0.001) and more weight gain (3.6 +/- 4.0 vs. 2.5 +/- 4.0 kg, P < 0.0001). LM75/25 patients had a higher overall hypoglycemia rate than GL patients (28.0 +/- 41.6 vs. 23.1 +/- 40.7 episodes x pt(-1) x year(-1), P = 0.007) but lower nocturnal hypoglycemia rate (8.9 +/- 19.3 vs. 11.4 +/- 25.3 episodes x pt(-1) x year(-1), P = 0.009). Severe hypoglycemia rates were low in both groups (LM75/25: 0.10 +/- 1.6 vs. GL: 0.03 +/- 0.3 episodes x pt(-1) x year(-1), P = 0.167). CONCLUSIONS: Compared with GL, LM75/25 resulted in slightly lower A1C at 24 weeks and a moderately higher percentage reaching A1C target <7.0%. Patients receiving LM75/25 experienced more weight gain and higher rates of overall hypoglycemia but lower rates of nocturnal hypoglycemia. Durability of regimens will be evaluated in the following 2-year maintenance phase.

High-dose insulin therapy: is it time for U-500 insulin?

OBJECTIVE: To provide an overview of U-500 regular insulin action, review published clinical studies with U-500 regular insulin, and offer guidance to practicing endocrinologists for identifying patients for whom U-500 regular insulin may be appropriate. METHODS: This review has been produced through a synthesis of relevant published literature compiled via a literature search (MEDLINE search of the English-language literature published between January 1969, and July 2008, related to U-500, insulin resistance, concentrated insulin, high-dose insulin, insulin pharmacokinetics, and diabetes management) and the authors' collective clinical experience. RESULTS: The obesity epidemic is contributing to an increase in the prevalence of type 2 diabetes, as well as to increasing insulin requirements in insulin-treated patients. Many of these patients exhibit severe insulin resistance, manifested by daily insulin requirements of 200 units or greater or more than 2 units/kg. Delivering an appropriate insulin volume to these patients can be difficult and inconvenient and may be best accomplished with U-500 regular insulin by multiple daily injections or with continuous subcutaneous insulin infusion, rather than with standard U-100 insulin. Implementation of U-500 regular insulin in patients previously on other insulin formulations is described with a treatment algorithm covering dosage requirements ranging from 150 to more than 600 units per day on the basis of the authors' experience. CONCLUSIONS: Regimen conversion of appropriately selected patients from high-dose, U-100 insulin to U-500 regular insulin therapy on the basis of the recommendations presented in this article may potentially result in improved glycemic control and lower cost.

Advancing insulin therapy in type 2 diabetes previously treated with glargine plus oral agents: prandial premixed (insulin lispro protamine suspension/lispro) versus basal/bolus (glargine/lispro) therapy.

OBJECTIVE: The purpose of this study was to compare two analog insulin therapies (prandial premixed therapy [PPT] versus basal/bolus therapy [BBT]) in type 2 diabetic patients previously treated with insulin glargine (>or=30 units/day) plus oral agents, with the aim of demonstrating noninferiority of PPT to BBT. RESEARCH DESIGN AND METHODS: Patients were randomly assigned to PPT (lispro mix 50/50: 50% insulin lispro protamine suspension and 50% lispro; n = 187) t.i.d. with meals or BBT (glargine at bedtime plus mealtime lispro; n = 187) in a 24-week, multicenter, open-label, noninferiority trial. Investigators could replace lispro mix 50/50 with lispro mix 75/25 at the evening meal if the fasting plasma glucose target was unachievable. RESULTS: Baseline A1C was similar (PPT 8.8%; BBT 8.9%; P = 0.598). At week 24, A1C was lower with BBT (6.78 vs. 6.95%, P = 0.021). A1C was reduced significantly from baseline for both therapies (P < 0.0001). The difference in A1C change from baseline to the end point (BBT minus PPT) was -0.22% (90% CI -0.38 to -0.07). Noninferiority of PPT to BBT was not demonstrated based on the prespecified noninferiority margin of 0.3%. The percentages of patients achieving target A1C <7.0% (PPT versus BBT, respectively) were 54 vs. 69% (P = 0.009) and for target

Effect of growth hormone replacement on BMD in adult-onset growth hormone deficiency.

UNLABELLED: To determine if replacement of GH improves BMD in adult-onset GHD, we administered GH in physiologic amounts to men and women with GHD. GH replacement significantly increased spine BMD in the men by 3.8%. INTRODUCTION: Growth hormone (GH) deficiency (GHD) acquired in adulthood results in diminished BMD; the evidence that replacement of GH improves BMD is not conclusive. We therefore performed a randomized, placebo-controlled trial to determine whether GH replacement would increase lumbar spine BMD in a combined group of men and women with adult-onset GHD. MATERIALS AND METHODS: We randomized 67 men and women to receive GH (n=33) or placebo (n=34) for 2 yr. The GH dose was initially 2 microg/kg body weight/d, increased gradually to a maximum of 12 microg/kg/d and adjusted to maintain a normal IGF-I concentration for age and sex. BMD was assessed before treatment and at 6, 12, 18, and 24 mo of treatment. Fifty-four subjects completed the protocol. RESULTS: BMD of the lumbar spine in the entire group increased by 2.9 +/- 3.9% above baseline in the GH-treated subjects, which was significantly (p=0.037) greater than the 1.4 +/- 4.5% increase in the placebo-treated subjects. In a secondary analysis, spine BMD in GH-treated men increased 3.8 +/- 4.3% above baseline, which was significantly (p=0.001) greater than that in placebo-treated men (0.4 +/- 4.7%), but the change in GH-treated women was not significantly different from that in placebo-treated women. Treatment with GH did not increase total hip BMD more than placebo treatment after 2 yr. CONCLUSIONS: We conclude that GH replacement in men who have adult-onset GHD improves their spine BMD, but we cannot draw any conclusions about the effect of GH replacement on spine BMD in women with adult-onset GHD.

Role of environmental pollutants on immune functions, parasitic infections and limb malformations in marine toads and whistling frogs from Bermuda.

Soil, water, and amphibian tissues collected between 1995 and 1999 from 15 study sites in Bermuda were analysed for pesticides and heavy metals. The most abundant pesticide residue in soil was p,p'-dichlorodiphenyldichloroethylene (DDE) which was found at all sites in concentrations ranging from 0.003 to 4.023 p.p.m. No pesticide residues were found in water. DDE was also recovered from the livers and fat bodies of marine toads (Bufo marinus) and whistling frogs (Eleutherodactylus johnstonei). Analyses of food sources consumed by these anuran species revealed residue levels of p, p'-DDE ranging from 0.05 to 0.217 p.p.m. Other soil residues included dichlorodiphenyltrichloroethane (DDT) at eight study sites, Dicofol(kelthane) at eight sites, dieldrin at five sites, and polychlorinated biphenyls (PCBs) as Arochlor 1254 and Arochlor 1260 at seven sites. Analyses of toad livers revealed significant concentrations of cadmium, chromium, copper and zinc. Livers of Bermuda toads exhibited altered hepatocytic morphology and an increased number of melanomacrophages and possible granulomas, while spleens showed a marked decrease in white pulp. Spleen cells from Bufo marinus collected at one site having high levels of cadmium exhibited a decreased B cell response to lipopolysaccharide. The incidence of trematode infection in Bufo marinus increased from 53.8% in 1995 to 90% in 1999. Deformity rates in the limbs of subadult and adult toads ranged between 15 and 25%. Examination of 1,995 newly-metamorphosed toads revealed deformity rates as high as 47%. The current comprehensive study suggests that environmental pollutants may account for immunosuppression, increased susceptibility to infections, limb malformations and possible decline in amphibian populations from Bermuda.