Contaminants of Emerging Concern in Wastewaters in Barbados, West Indies.

There have been few reports in the peer-reviewed literature on the levels of contaminants of emerging concern (CECs) in municipal wastewater from the Caribbean region. In this study of wastewater collected from two wastewater treatment plants in Barbados, caffeine and ibuprofen were detected at µg/L concentrations, whereas two steroid hormones (i.e. androstenedione, estrone) and several prescription pharmaceuticals were detected at ng/L concentrations. Among drugs of abuse, benzoylecgonine (i.e. metabolite of cocaine), MDMA (i.e. Ecstasy) and MDA (i.e. 3,4-methylenedioxyamphetamine) were present at the highest concentrations in untreated wastewater. Overall, these data show that there is potential impact in the marine environment in Barbados from CECs discharged into the coastal zone.

Contaminants of emerging concern in surface waters in Barbados, West Indies.

Contaminants of emerging concern (CECs), including pharmaceuticals, artificial sweeteners, steroid hormones, and current-use pesticides have been detected in surface waters around the world, but to date, there have been no reports in the peer-reviewed literature on the levels of these classes of contaminants in freshwater resources in the Caribbean region. In the present study, multi-residue solid phase extraction (SPE) and liquid chromatography with tandem mass spectroscopy (LC-MS/MS) were used to analyze grab samples of surface waters collected from five different watersheds in Barbados, West Indies. The artificial sweeteners (AS), acesulfame, cyclamate, saccharin, and sucralose were widely detected in the watersheds, indicating contamination from domestic wastewater, and the concentrations of these chemical tracers in water were correlated with the concentrations of the non-prescription pharmaceutical, ibuprofen (R 2 values of 0.4-0.6). Surprisingly, the concentrations of another chemical tracer of domestic wastewater, caffeine were not correlated with ibuprofen or AS concentrations. Several other prescription pharmaceuticals and the steroid hormones, estrone and androstenedione, were detected in selected watersheds at low ng/L concentrations. The fungicide, chlorothalonil was widely detected in surface waters at low (< 10 ng/L) concentrations, but the levels of this pesticide were not correlated with the concentrations of the other target analytes, indicating that the source of this pesticide is not domestic wastewater. An informal survey of disposal practices for out of date or unused drugs by pharmacies in Barbados indicated that disposal into trash destined for the landfill and flushing down the sink might be significant sources of contamination of water resources by pharmaceuticals.

Definitions, methodological and statistical issues for phase 3 clinical trials in chronic myeloid leukemia: a proposal by the European LeukemiaNet.

The treatment policy of chronic myeloid leukemia (CML), particularly with tyrosine kinase inhibitors, has been influenced by several recent studies that were well designed and rapidly performed, but their interpretation is of some concern because different end points and methodologies were used. To understand and compare the results of the previous and future studies and to translate their conclusion into clinical practice, there is a need for common definitions and methods for analyses of CML studies. A panel of experts was appointed by the European LeukemiaNet with the aim of developing a set of definitions and recommendations to be used in design, analyses, and reporting of phase 3 clinical trials in this disease. This paper summarizes the consensus of the panel on events and major end points of interest in CML. It also focuses on specific issues concerning the intention-to-treat principle and longitudinal data analyses in the context of long-term follow-up. The panel proposes that future clinical trials follow these recommendations.

Low JAK2 V617F Allele Burden in Ph-Negative Chronic Myeloproliferative Neoplasms Is Associated with Additional CALR or MPL Gene Mutations.

JAK2 (Janus kinase 2) V617F, CALR (Calreticulin) exon 9, and MPL (receptor for thrombopoietin) exon 10 mutations are associated with the vast majority of Ph-negative chronic myeloproliferative neoplasms (MPNs). These mutations affect sequential stages of proliferative signal transduction and therefore, after the emergence of one type of mutation, other types should not have any selective advantages for clonal expansion. However, simultaneous findings of these mutations have been reported by different investigators in up to 10% of MPN cases. Our study includes DNA samples from 1958 patients with clinical evidence of MPN, admitted to the National Research Center for Hematology for genetic analysis between 2016 and 2019. In 315 of 1402 cases (22.6%), CALR mutations were detected. In 23 of these 315 cases (7.3%), the JAK2 V617F mutation was found in addition to the CALR mutation. In 16 from 24 (69.6%) cases, with combined CALR and JAK2 mutations, V617F allele burden was lower than 1%. A combination of JAK2 V617F with MPL W515L/K was also observed in 1 out of 1348 cases, only. JAK2 allele burden in this case was also lower than 1%. Additional mutations may coexist over the low background of JAK2 V617F allele. Therefore, in cases of detecting MPNs with a low allelic load JAK2 V617F, it may be advisable to search for other molecular markers, primarily mutations in exon 9 of CALR. The load of the combined mutations measured at different time points may indicate that, at least in some cases, these mutations could be represented by different clones of malignant cells.

Female breast cancer risk in Bryansk Oblast, Russia, following prolonged low dose rate exposure to radiation from the Chernobyl power station accident.

BACKGROUND: Ionizing radiation is a known cause of female breast cancer, but there have been few studies of the risk after prolonged radiation exposure at low dose rates. METHODS: This population-based case-control study estimated breast cancer risk after ∼25 years' exposure to radiation from the Chernobyl accident. Cases (n = 468) were women ≤55 years old when first diagnosed with invasive breast cancer during October 2008 through February 2013, who lived in Bryansk Oblast, Russia at the time of the accident and their diagnoses. Controls, individually matched to cases on birth year, administrative district of residence and urban vs non-urban settlement during the accident, were women without breast cancer who lived in Bryansk Oblast at the time of the accident and on their cases' diagnosis dates (n = 468). Subjects were interviewed regarding residence, dietary and food source histories to support individualized estimation of their radiation doses to the breast, which ranged from 0.04 - 41 centigray (cGy) (mean 1.3 cGy). RESULTS: In multivariable analyses, the odds ratio for breast cancer risk was 3.0 [95% confidence interval (CI): 1.3, 7.0] and 2.7 (95% CI: 1.0, 7.3) in the seventh and eighth dose octiles, respectively, relative to the lowest octile. Analyses of dose effect modification suggested that radiation-related risk may have been higher in women who were younger at the time of the accident and/or at the time of diagnosis. CONCLUSIONS: This study suggests that prolonged exposure to ionizing radiation at low dose rates can increase risk of breast cancer.

Micropollutants related to human activity in groundwater resources in Barbados, West Indies.

Several micropollutants, including caffeine, artificial sweeteners, pharmaceuticals, steroid hormones and a current-use pesticide were analyzed in water samples collected from five groundwater pumping stations in Barbados. The presence of caffeine and three artificial sweeteners (i.e. acesulfame, sucralose, saccharin) in groundwater samples indicated that groundwater was being contaminated by infiltration of wastewater into the karst aquifer. An estrogen (i.e. estrone), three pharmaceuticals (i.e. carbamazepine, trimethoprim, ibuprofen) and a transformation product of the fungicide, chlorothalonil (i.e. 4-hydroxychlorothalonil) were also detected at ng/L concentrations in groundwater collected from two or more pumping sites. The concentrations of carbamazepine and trimethoprim were correlated with the concentrations of caffeine (R2 values of 0.70 to 0.80), indicating pharmaceutical contamination of groundwater by infiltration from domestic wastewater. The concentrations of caffeine were generally higher in groundwater samples collected in June during the wet season relative to the concentrations in samples collected in February during the dry season, indicating that infiltration of contaminants is higher during periods of heavy rainfall. Rapid rates of degradation and relatively slow rates of infiltration may explain why several target analytes were not detected in groundwater. Elevated concentrations of 4-hydroxychlorothalonil > 0.1 µg/L in samples collected at two of the monitoring sites warrant further studies on the sources and the distribution of this compound and other pesticides used in agriculture and for turf-treatment (e.g. golf courses). Overall, more data are needed in order to implement mitigation strategies that are effective in reducing chemical contamination in groundwater in Barbados.

Childhood thyroid cancer, radiation dose from Chernobyl, and dose uncertainties in Bryansk Oblast, Russia: a population-based case-control study.

A population-based case-control study was conducted to estimate the radiation-related risk of thyroid cancer in persons who were exposed in childhood to (131)I from the Chernobyl accident of April 26, 1986 and to investigate the impact of uncertainties in individual dose estimates. Included were all 66 confirmed cases of primary thyroid cancer diagnosed from April 26, 1986 through September 1998 in residents of Bryansk Oblast, Russia, who were 0-19 years old at the time of the accident, along with two individually matched controls for each case. Thyroid radiation doses, estimated using a semi-empirical model based on environmental contamination data and individual characteristics, ranged from 0.00014 Gy to 2.73 Gy and had large uncertainties (median geometric standard deviation 2.2). The estimated excess relative risk (ERR) associated with radiation exposure, 48.7/Gy, was significantly greater than 0 (P = 0.00013) but had an extremely wide 95% confidence interval (4.8 to 1151/Gy). Adjusting for dose uncertainty nearly tripled the ERR to 138/Gy, although this was likely an overestimate due to limitations in the modeling of dose uncertainties. The radiation-related excess risk observed in this study is quite large, especially if the uncertainty of dose estimation is taken into account, but is not inconsistent with estimates previously reported for risk after (131)I exposure or acute irradiation from external sources.

Caffeine in surface and wastewaters in Barbados, West Indies.

Caffeine, a purine alkaloid drug, has been recognized as a contaminant of water bodies in various climatic regions, however, these environmental caffeine concentrations are the first to be reported in the tropical Caribbean. The major objective of this study was to develop an improved method to extract caffeine from surface and wastewaters in the warm Caribbean environment and measure caffeine concentrations in highly populated areas in Barbados. Caffeine was extracted from water via solid phase extraction (SPE); the acidified water samples were loaded onto C-18 cartridges and eluted with pure chloroform. The extracted caffeine was quantified using gas chromatography - mass spectroscopy - multiple reaction monitoring (GC-MS/MS-MRM). Method detection limits of 0.2 ng L(-1) from 1 L water samples were achieved. Caffeine was detected in all environmental water samples investigated. The concentrations of caffeine in surface waters were detected in the range 0.1 - 6.9 µg L(-1). The two wastewater treatment plants, primary and secondary treatment systems, significantly differed in their ability to eliminate caffeine in the raw sewage (38% and 99% caffeine removal efficiencies respectively). Thus, it may be essential to employ secondary treatment to effectively remove caffeine from wastewater systems in Barbados. Caffeine in water bodies are principally attributed to anthropogenic sources as caffeine-producing plants are not commonly grown on the island of Barbados. The study also shows the recalcitrance of caffeine to hydrolytic degradation.

Histopathologic verification of acute leukemia (AL) in a cohort of 463 post-Chernobyl patients from Belarus, Russia and Ukraine.

Seven morphologists examined 382 slide and 82 non-slide, post-Chernobyl pediatric acute leukemia (AL) cases in radiation-exposed areas of Belarus, Russia and Ukraine; part of a case-control study by the International Consortium for Research on the Health Effects of Radiation. Among the slide cases, 99% were confirmed as AL: 92% acute lymphoid leukemia (ALL) and 86% acute myeloid leukemia (AMD demonstrating the utility of FAB classification for distinguishing ALL and AML. Among the non-slide cases, 79% were confirmed as AL: 84% ALL, and 71% AML. This study affirms AL diagnostic accuracy during a time of social upheaval in the former Soviet Union.

Risk of thyroid cancer in the Bryansk Oblast of the Russian Federation after the Chernobyl Power Station accident.

This population-based case-control study investigated whether exposure to radiation from the Chernobyl Power Station accident is associated with an increased risk of thyroid cancer in children and adolescents aged 0-19 years at the time of the accident who were residing in the more highly contaminated areas of the Bryansk Oblast. Cases were diagnosed with thyroid cancer before October 1, 1997 (n = 26); two controls per case were identified from the Russian State Medical Dosimetrical Registry and were matched by gender, birth year, and raion of residence and type of settlement (urban, town, rural) on April 26, 1986 (n = 52). Individual radiation doses to the thyroid were estimated using a semi-empirical model and data were collected in interviews, primarily of the participants' mothers. Based on a loglinear dose-response model treating estimated dose as a continuous variable, the trend of increasing risk with increasing dose was statistically significant (one-sided P = 0.009). These data suggest that exposure to radiation from Chernobyl is associated with an increased risk of thyroid cancer, and that the relationship is dependent on dose. These findings are consistent with descriptive reports from contaminated areas of Ukraine and Belarus, and the quantitative estimate of thyroid cancer risk is generally consistent with estimates from other radiation-exposed populations.