Degradation of triclosan and triclocarban and formation of transformation products in activated sludge using benchtop bioreactors.

Benchtop bioreactors were run aerobically with activated sludge samples collected from a large municipal wastewater treatment plant (WWTP) to understand how increased hydraulic retention time (HRT), sludge retention time (SRT), and varying treatment temperatures (21°C and 30°C) impact concentrations of the endocrine disrupting antimicrobials triclosan (TCS), triclocarban (TCC), and their transformation products. Samples from the reactors were collected periodically over a 122-196h period and the solid and liquid fraction were separately quantitated for TCS, TCC, and methyltriclosan (MeTCS) and scanned qualitatively for six other transformation products. Results indicated that TCS, TCC and MeTCS were predominately associated with the solids fraction of the activated sludge with only nominal concentrations in the liquids fraction. TCS was degraded in the solids fraction, with increased rates at 30°C (-0.0224 ± 0.007h-1) when compared to reactors run at 21°C (- 0.0170 ± 0.003h-1). Conversely, TCC concentrations did not significantly change in solids samples from reactors run at 21°C, while an increase in reactor temperature to 30°C resulted in TCC degradation at an average rate of - 0.0158 ± 0.012h-1. Additionally, MeTCS formation in the solids fraction was observed in three out of four reactors run - indicating a notable transformation of TCS. Qualitative appearance of 2,4-dichlorophenol and 4-chloroanaline was observed in the liquids fraction of all reactor samples. The remaining four qualitatively scanned compounds were not detected. These experiments demonstrate that increased HRT, SRT, and temperature result in enhanced removal of TCS and TCC from wastewater during the activated sludge process. Furthermore, a substantial formation of TCS into MeTCS was observed.

Fate of four phthalate plasticizers under various wastewater treatment processes.

The fate of four phthalate plasticizers during wastewater treatment processes at six different wastewater treatment plants (WWTPs) was investigated. Concentrations of benzyl butyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), and diisodecyl phthalate (DiDP) were determined prior to either aerobic or anaerobic (conventional and advanced) treatment, after treatment, and in final, dewatered solids. Despite their elevated use worldwide, the fate of DiNP and DiDP during wastewater treatment have not been well characterized. DEHP was readily degraded during aerobic treatments while anaerobic digestion resulted in either no significant change in concentrations or an increase in concentration, in the case of more advanced anaerobic processes (thermal hydrolysis pretreatment and a two-phase acid/gas process). Impacts of the various treatment systems on DiNP, DiDP, and BBP concentrations were more varied - anaerobic digestion led to significant decreases, increases, or no significant change for these compounds, depending on the treatment facility, while aerobic treatment was generally effective at degrading the compounds. Additionally, thermal hydrolysis pretreatment of sludge prior to anaerobic digestion resulted in increases in DiNP, DiDP, and BBP concentrations. The predicted environmental concentrations for all four compounds in soils after a single biosolids application were calculated and the risk quotients for DEHP in soils were determined. The estimated toxicity risk for DEHP in soils treated with a single application of sludge from any of the six studied WWTPs is lower than the level of concern for acute and chronic risk, as defined by the US EPA.

Temporal trends of perfluoroalkyl substances in limed biosolids from a large municipal water resource recovery facility.

While the recycling of wastewater biosolids via land-application is a sustainable practice for nutrient recovery and soil reclamation that has become increasingly common worldwide, concerns remain that this practice may become a source of toxic, persistent organic pollutants to the environment. This study concentrates on assessing the presence and the temporal trends of 12 perfluoroalkyl substances (PFASs), pollutants of global consequence, in limed Class B biosolids from a municipal water resource recovery facility (WRRF), also know as a wastewater treatment plant. PFASs are of significant concern due to their extensive presence and persistence in environmental and biotic samples worldwide, most notably human blood samples. Class B biosolids were collected from the WRRF, prior to land-application, approximately every two to three months, from 2005 to 2013. Overall, this study found that concentrations of the 7 detectable PFAS compounds remained unchanged over the 8-year period, a result that is consistent with other temporal studies of these compounds in sewage sludges. From these analyzed compounds, the highest mean concentrations observed over the study period were 25.1 ng/g dw, 23.5 ng/g dw, and 22.5 ng/g dw for perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), and perfluorooctanesulfonic acid (PFOS), respectively, and these compounds were detected at concentrations 2.5-5 times higher than the remaining, detectable PFASs. Furthermore, it was observed that PFOS, while demonstrating no overall change during the study, exhibited a visible spike in concentration from late 2006 to early 2007. This study indicates that concentrations of PFASs in WRRFs have been stagnant over time, despite regulation. This study also demonstrates that the use of glass jars with polytetrafluoroethylene-lined lids, a common storage method for environmental samples, will not influence PFOA and PFNA concentrations in archived biosolids samples.

Clinical application of emerging sensor technologies in diabetes management: consensus guidelines for continuous glucose monitoring (CGM).

Continuous glucose monitoring (CGM) is an evolving technology poised to redefine current concepts of glycemic control and optimal diabetes management. To date, there are few randomized studies examining how to most effectively use this new tool. Therefore, a group of eight diabetes specialists heard presentations on continuous glucose sensor technology and then discussed their experience with CGM in order to identify fundamental considerations, objectives, and methods for applying this technology in clinical practice. The group concluded that routine use of CGM, with real-time data showing the rate and direction of glucose change, could revolutionize current approaches to evaluating and managing glycemia. The need for such progress is indicated by the growing prevalence of inadequately treated hyperglycemia. Coordinating financial and educational resources and developing clear protocols for using glucose sensor technology are urgent priorities in promoting wide adoption of CGM by patients and health care providers. Finally, researchers, manufacturers, payers, and advocacy groups must join forces on the policy level to create an environment conducive to managing continuous data, measuring outcomes, and formalizing best practices.

Evaluation of a patient education booklet (SimpleStart) effect on postprandial glucose control in type 2 diabetes.

BACKGROUND: Post-meal hyperglycemia is emerging as a cardiovascular risk factor and may be elevated despite a hemoglobin A1C (A1C) of <7%. The Simple Start DVD (LifeScan, Milpitas, CA) was developed to educate patients about glycemic targets and dietary changes that could lessen glycemic excursions. We evaluated SimpleStart in a controlled, randomized, prospective trial using continuous glucose monitoring (CGM). METHODS: Thirty subjects with type 2 diabetes mellitus having an A1C of <7.0% (mean 6.0%) were recruited from the Center's population. Subjects were randomized to either Simple Start DVD presentation and a 30-min diet education course (SS Group) or just the latter (Control Group). Subjects were seen at baseline and during weeks 6 and 12 by an investigator. Life-style and medication changes were advised based on history and self-monitored blood glucose downloaded meter data. CGM and A1C were done at baseline and during weeks 6 and 12. RESULTS: Twenty-eight subjects completed the 12-week study with 14 subjects in the SS Group and Control Group being compared. There was no significant difference in the baseline or subsequent A1C levels or overall CGM glucose values between groups or over time. SMBG frequency was significantly increased in the SS Group from <1.0 per day to 2.0 per day (P < 0.001). At week 12, the mean glucose for the 4-h after-meal period was significantly lower in the SS Group than in the Control Group at breakfast and lunch in those subjects with adequate CGM tracings (P < 0.05). CONCLUSION: An educational program incorporating Simple Start facilitates patient behavioral changes, decreasing post-meal hyperglycemia.

Influence of thermal hydrolysis-anaerobic digestion treatment of wastewater solids on concentrations of triclosan, triclocarban, and their transformation products in biosolids.

The growing concern worldwide regarding the presence of emerging contaminants in biosolids calls for a better understanding of how different treatment technologies at water resource recovery facilities (WRRFs) can influence concentrations prior to biosolids land application. This study focuses on the influence of solids treatment via the Cambi Thermal Hydrolysis Process™ in conjunction with anaerobic digestion (TH-AD) on concentrations of triclosan (TCS), triclocarban (TCC), and their transformation products in biosolids and sludges. Concentrations of the target analytes in biosolids from the TH-AD process (Class A), sludges from the individual TH-AD treatment steps, and limed biosolids (Class B) from the same WRRF were compared. TCC concentrations were significantly lower in Class A biosolids than those in the Class B product - a removal that occurred during thermal hydrolysis. Concentrations of TCS, methyl triclosan, and 2,4-dichlorophenol, conversely, increased during anaerobic digestion, leading to significantly higher concentrations of these compounds in Class A biosolids when compared to Class B biosolids. Implementation of the TH-AD process had mixed effect on contaminant concentrations.

Exploring methods to extend the reach of diabetes specialist expertise into primary care clinics.

The purpose of this article is to describe a pilot program using centralized diabetes specialist services to guide primary care treatment of diabetes. The program demonstrated the feasibility of disseminating diabetes treatment guidance from a centralized diabetologist clinic. Across all participating sites, approximately 50% of patients achieved HbA1c values of 6.9% or lower. Approximately 80% of all patients participating achieved low-density lipoprotein cholesterol values of 129 mg/dL or lower, and 50% had systolic blood pressure values of 129 mm Hg or lower. Results of the program are promising and deserve further study. Hallmarks of the program include dissemination of diabetes care through midlevel practitioners in primary care offices, using standardized algorithms, and computer-assisted guidance of therapy.

Lipid response to pioglitazone in diabetic patients: clinical observations from a retrospective chart review.

The objective of this study was to determine whether improvements in the lipid profile observed in controlled clinical trials with pioglitazone are seen in the clinical practice setting, and to ascertain the influence of concurrent statin treatment. Charts of 100 consecutive patients with type 2 diabetes (mean age 56.8 years) treated with pioglitazone (45 mg/day) for 2-4 months were retrospectively analyzed for changes in serum lipids, glycemic parameters, and body weight. Subanalyses were performed on the relationship of lipid changes to baseline lipid values and to concurrent statin therapy. Pioglitazone was associated with statistically significant (p < 0.001) changes from baseline in HbA(1C) (mean decrease 1.09%), body weight (mean increase 1.76 kg), HDL cholesterol (HDL-C) levels (mean increase 15.6%), and triglycerides (mean decrease 9.9%). There was an increase (+ 1.09%) in mean individual LDL-C levels from baseline values, but this change was not statistically significant. The greatest absolute and percentage improvements in HDL-C and triglycerides were observed in patients who had the greatest lipid abnormalities at baseline: in patients with baseline HDL-C < 35 mg/dL, mean individual HDL-C values increased by 31% (p < 0.001); in those with baseline triglycerides >399 mg/dL, triglyceride levels decreased by 46% (p < 0.001); and in patients with baseline LDL-C > 129 mg/dL, mean individual LDL-C values decreased by 10.6% (p < 0.001). Subgroup analysis showed similar beneficial changes in HDL-C and triglycerides in patients who were not receiving concurrent statin therapy (n = 48) as in those who were receiving statins (n = 49). This observational study demonstrated that significant improvements in HDL-C and triglyceride levels can be achieved with pioglitazone in the clinical practice setting. The greatest improvements occurred in patients with the worst baseline lipid levels, and benefits were seen regardless of whether patients were receiving concurrent statin therapy.

Agreement between glucose trends derived from three simultaneously worn continuous glucose sensors.

BACKGROUND: Sensors detect the rate and direction of glucose trend. They need to be accurate and reproducible as could be evidenced by strong agreement between multiple sensors. We evaluated this relationship through simultaneously worn glucose sensors using several methods of slope analysis. METHODS: Ten type 1 diabetic, insulin pump-treated subjects were studied while simultaneously wearing three CGMS Gold sensors each. Sensors were placed in the right abdomen (reference), left abdomen, and left upper arm. Sensors were calibrated and chronologically aligned. Data were only interpreted and included if there were 24 hours of data simultaneously obtained from all three sensors. RESULTS: Using a two-point derived slope, increasing the duration of the trend from 5 to 60 minutes improved agreement between sensors. Using a 20-minute rolling average trend (using every 5-minute glucose value during the 20 minutes) improved the agreement to 94.3%. Finally, using whichever of the two comparator sensor rolling average trends was closest to the reference (better of two), the agreement improved to 98.2%. However, for these trend analysis methods, when the absolute reference rate of change was more than 1 mg/dl/min, the agreement decreased. Even with the best analysis approach, at an absolute reference sensor rate of change of >2 mg/dl/min, the agreement between sensors was only 40.0%. CONCLUSION: Despite several methods of analysis, trend agreement from multiple sensors diminishes as the absolute rate of change of reference glucose increases.

A prospective evaluation of insulin dosing recommendations in patients with type 1 diabetes at near normal glucose control: Basal dosing.

BACKGROUND: Current basal insulin dosing recommendations are based on retrospective studies of Type 1 patients with diabetes in whom the glucose control was not intensely established. Using continuous glucose monitoring (CGM) we prospectively studied these recommendations in patients treated with continuous subcutaneous insulin infusion. METHODS: With CGM 30 subjects were titrated with daily insulin adjustments to achieve a basal glucose targets of <5% of values <70 mg/dl and <20%, >170 mg/dl. The basal rate during meal time was studied by a sequential daily single meal omission until the glucose goals were achieved. RESULTS: Glucose targets were achieved in all subjects. The observed ratios of total basal dose (TBD) to total daily dose and TBD to weight, in kilograms, were 0.384 and 0.185, respectively. Previously reported formulas for estimating the TBD resulted in significantly higher values than we observed. The difference between the maximum to the minimum hourly basal insulin infusion rate was more than 100% and the peak rate was reached by 0200 hours in 73% of subjects. During the post study observation period in which there was no further study intervention and in those subjects with baseline A1C >6.9%, the A1C decreased 0.45 % (p = 0.0110) in a mean of 12.8 weeks. CONCLUSIONS: Current literature overestimates TBD dose and underestimates the degree and the time of onset of the dawn phenomenon. Maintaining near normal glycemia in the ambulatory setting may be achieved in selected Type 1 patients for at least two weeks and maybe longer.

A prospective evaluation of insulin dosing recommendations in patients with type 1 diabetes at near normal glucose control: bolus dosing.

BACKGROUND: Current bolus insulin dosing recommendations are based on retrospective studies of patients with Type 1 diabetes in whom the glucose control was not intensely established. Using continuous glucose monitoring (CGM), we prospectively studied these recommendations in patients treated with continuous subcutaneous insulin infusion. METHODS: Thirty subjects were studied over a mean of two weeks of continuous glucose monitoring with near daily insulin adjustments. First a basal glucose goal was achieved of <5% of values <70 mg/dL and <20%>, 170 mg/dL. Then bolus dosing factors; Insulin to Carbohydrate Ratio (g of meal carbohydrates/unit of insulin, ICR) and Correction Factor (mg/dL fall in blood glucose/unit of insulin, CF); were established for each meal time to a goal of +/- 20% of premeal glucose (ICR) or 80-120 mg/dL (CF) by the fourth post bolus hour. RESULTS: All treatment goals were achieved in each subject. Modification of formulas from ICR = 450/Total Daily Dose (TDD) to ICR = (217/TDD) + 3 and from CF = 1700/TDD to CF = (1076/TDD) + 12 more closely matched observed results than published formulas. There was no significant difference in each factor with time of day. There was a highly significant relationship between ICR and CF, ICR*4.44 = CF (r = 0.9, p < 0.0005), total basal dose (TBD) and TDD. CONCLUSIONS: Current formulas need to be modified to provide higher insulin bolus doses. The interrelationships between ICR, CF, TBD and TDD suggest that any change in one may require a change in the others.

Basal bolus dosing: a clinical experience.

Basal bolus insulin dosing (BBD) may be defined as the physiological replacement of basal and bolus insulin to achieve near normal glycemia without hypoglycemia and loss of life quality. Normally, continuous and variable basal insulin release provides partial suppression of hepatic glucose production to maintain euglycemia during the fasting period. With meals, additional insulin is released in a biphasic pattern to further suppress hepatic glucose production and to increase glucose transport into muscle, fat and liver. Newer subcutaneous insulins for bolus and basal mimic near normal secretion. In addition, improvements in continuous subcutaneous insulin infusion pump features such as dual wave insulin delivery allow improved postprandial glycemia. Insulin dosing is done in a three step process. Firstly, the dosage is estimated based on formulas derived from body weight or previous insulin requirements. Secondly, pre-dosing adjustments modify these formulas by considering estimations of insulin sensitivity based on clinical judgment and laboratory evaluations. Lastly, post-dosage adjustments are based on timed, self-monitored, blood glucose determinations assisted by overall average glucose determinations such as hemoglobin A1c. Continuous glucose monitoring systems have provided a more insightful tool for dosage adjustments. Daily consecutive intensive glucose evaluations using a continuous glucose monitoring system and corresponding dosage adjustments may offer an even better tool for insulin dosing selection.