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The appropriate use of human biomonitoring data to model population chemical exposures is challenging, especially for rapidly metabolized chemicals, such as agricultural chemicals. The objective of this study is to demonstrate a novel approach integrating model predicted dietary exposures and biomonitoring data to potentially inform regulatory risk assessments. We use lambda-cyhalothrin as a case study, and for the same representative U.S. population in the National Health and Nutrition Examination Survey (NHANES), an integrated exposure and pharmacokinetic model predicted exposures are calibrated to measurements of the urinary metabolite 3-phenoxybenzoic acid (3PBA), using an approximate Bayesian computing (ABC) methodology. We demonstrate that the correlation between modeled urinary 3PBA and the NHANES 3PBA measurements more than doubled as ABC thresholding narrowed the acceptable tolerance range for predicted versus observed urinary measurements. The median predicted urinary concentrations were closer to the median measured value using ABC than using current regulatory Monte Carlo methods.

Polycyclic aromatic hydrocarbons (PAHs) are a class of compounds of environmental and public health concern because of their toxicity and environmental ubiquity that will be further exacerbated by increasing anthropogenic pollution. In situ bioremediation is a common cleanup technique for PAH-contaminated soils because it is considered to be cost-effective and environmentally-friendly. However, PAHs are often bound to nonpolar soil domains and become resistant to microbial degradation, the primary PAH removal pathway. This dissertation addresses these limitations by evaluating bioremediation-enhancement technologies such as biosurfactant amendment, bioaugmentation, and phytoremediation to increase PAH bioavailability and/or soil microbial activity. The use of biosurfactants to increase PAH bioavailability has the potential to be an environmental alternative to synthetic surfactants. Therefore, rhamnolipid biosurfactant was compared to Brij-35 surfactant in two soils contaminated with 14C-pyrene that were also bioaugmented with a PAH-degrading microbe, Mycobacterium vanbaalenii PYR-1. The effect of the surfactants and bioaugmentation on PAH biodegradation and soil microbial community dynamics was evaluated. The addition of Brij-35 increased 14C-pyrene mineralization in both soils, but the rhamnolipid biosurfactant inhibited PAH degradation in a dose-dependent manner, which was likely due to preferential utilization of the biosurfactant as an easier carbon source by the degrading microorganisms. The bioaugmentation of M. vanbaalenii PYR-1 resulted in efficient 14C-pyrene dissipation. Using 16S rRNA analysis, it was determined that the pyrene biodegradation was associated with changes in the soil microbial communities. The addition of pyrene resulted in a large increase in Bacillus, a genus associated with PAH degradation. However, the addition of rhamnolipid biosurfactant decreased the abundance of Bacillus microorganisms, which was reflected in 14C-pyrene mineralizat

Polycyclic aromatic hydrocarbons (PAHs) are a class of compounds of environmental and public health concern because of their toxicity and environmental ubiquity that will be further exacerbated by increasing anthropogenic pollution. In situ bioremediation is a common cleanup technique for PAH-contaminated soils because it is considered to be cost-effective and environmentally-friendly. However, PAHs are often bound to nonpolar soil domains and become resistant to microbial degradation, the primary PAH removal pathway. This dissertation addresses these limitations by evaluating bioremediation-enhancement technologies such as biosurfactant amendment, bioaugmentation, and phytoremediation to increase PAH bioavailability and/or soil microbial activity. The use of biosurfactants to increase PAH bioavailability has the potential to be an environmental alternative to synthetic surfactants. Therefore, rhamnolipid biosurfactant was compared to Brij-35 surfactant in two soils contaminated with 14C-pyrene that were also bioaugmented with a PAH-degrading microbe, Mycobacterium vanbaalenii PYR-1. The effect of the surfactants and bioaugmentation on PAH biodegradation and soil microbial community dynamics was evaluated. The addition of Brij-35 increased 14C-pyrene mineralization in both soils, but the rhamnolipid biosurfactant inhibited PAH degradation in a dose-dependent manner, which was likely due to preferential utilization of the biosurfactant as an easier carbon source by the degrading microorganisms. The bioaugmentation of M. vanbaalenii PYR-1 resulted in efficient 14C-pyrene dissipation. Using 16S rRNA analysis, it was determined that the pyrene biodegradation was associated with changes in the soil microbial communities. The addition of pyrene resulted in a large increase in Bacillus, a genus associated with PAH degradation. However, the addition of rhamnolipid biosurfactant decreased the abundance of Bacillus microorganisms, which was reflected in 14C-pyrene mineralizat

Water treatment and reuse initiatives are essential to combat declining water supplies in a changing climate, especially in arid and semi-arid regions. Pollution of water resources intensifies the search for strategies to provide water for potable and non-potable reuse that mitigates detrimental ecological and human health effects. Fipronil and synthetic pyrethroids are common urban-use insecticides that exert aquatic toxicity at trace levels and have been often found in urban surface streams. In this study, samples were collected from the 182 ha Prado Wetlands in Southern California for seven months to assess the occurrence of fipronil and its degradation products as well as pyrethroids (bifenthrin and cyfluthrin) in water, sediment, and plants in a 4.45 ha vegetated surface flow constructed wetland (CW). Concentration-based removal values and changes in mass flux were calculated to determine the efficacy of CW treatment. Observed water concentrations were further used to calculate toxic units for the invertebrates Hyalella azteca and Chironomus dilutus. Pesticide concentrations in water, sediment, and plant samples consistently decreased during passage through the CW at all time points. Removal values for fipronil desulfinyl, fipronil sulfide, fipronil, fipronil sulfone, bifenthrin, and cyfluthrin were 100%, 99.7-100%, 57.8-88.1%, 75.6-100%, 74.7-100%, and 36.6-82.2%, respectively, and there was a general net deposition of pesticides into CW compartments. Toxic unit values decreased in every instance for both aquatic invertebrates. Settling of contaminated particles, adsorption to sediment, plant uptake or adsorption, and subsequent degradation contributed to the effective removal of these urban-use insecticides, which highlights the potential of CWs for protecting urban water quality.

Urban-use pesticides present a unique risk to non-target organisms in surface aquatic systems because impervious pavement facilitates runoff that may lead to serious contamination and ensuing aquatic toxicity. Fipronil is an insecticide used at high rates in urban environments, especially in regions such as California. This compound and its biologically active degradation products have been detected in urban runoff drainage and downstream surface water bodies at concentrations exceeding toxicity thresholds for sensitive aquatic invertebrates, necessitating a better understanding of the runoff sources and causes of this contamination at sites of application. In this study, we evaluated sorption of fipronil, fipronil desulfinyl, fipronil sulfide, and fipronil sulfone in urban dust, soil, and concrete, matrices commonly associated with the perimeter of a residential home. Samples were also collected from five single family homes treated with fipronil in Riverside, California, for five months to determine the occurrence of fipronil and its degradates in runoff water, urban dust, soil, and on concrete surfaces. Statistical analysis was performed to determine which urban matrices contributed more significantly to the contaminant levels in runoff water. Freundlich sorption coefficients for fipronil and its degradation products in dust were 3- to 9-fold greater than their values in soil. Fipronil and its degradates were detected in 100% of runoff samples and their presence was observed in dust, soil, and concrete wipe samples for 153 d after the treatment. Linear regression analysis showed that concrete surfaces were a primary source of all four compounds to runoff, and loose dust on concrete pavement also served as an important contributor. This study represents the first comprehensive investigation of the sources and causes for surface runoff contamination by fipronil and its degradation products. Findings highlight the importance to reduce fipronil residues on concrete s

Douglas C Wolf,1 Srihari Jaganathan,2 Chakkarin Burudpakdee,3 Arpamas Seetasith,3 Robert Low,2 Edward Lee,4 Jay Gucky,2 Mohamed Yassine,4 David A Schwartz5 1Atlanta Gastroenterology Associates, Atlanta, GA, 2UCB Pharma, Smyrna, GA, 3IQVIA, Fairfax, VA, 4UCB Pharma, Atlanta, GA, 5Inflammatory Bowel Disease Center, Vanderbilt University Medical Center, Vanderbilt University, Nashville, TN, USA Background: Patient support programs have a positive effect on adherence to therapy. Certolizumab pegol (CZP) is a tumor necrosis factor antagonist for the treatment of Crohn’s disease. Objectives: To assess, using real-world claims data, whether home health nurse assistance had an effect on patients’ adherence to CZP and to measure its impact on health care use and costs. Methods: A retrospective analysis of medical and pharmacy claims data from the IQVIA Real-World Data Adjudicated Claims Database was conducted using data from January 1, 2007 through September 30, 2015. CZP patients with Crohn’s disease were eligible to receive self-administration instructions from a nurse or nurse-administered CZP injections, or both. These services were provided by CIMplicity®, a home health nurse program sponsored by UCB Pharma. Cohorts were based on patients with and without nurse assistance and were matched based on gender and categorical age. Adherence to CZP was determined using the medication possession ratio (MPR) and proportion of days covered (PDC). A Kaplan–Meier analysis was performed to compare time to discontinuation of CZP between the two cohorts. Multivariate regression analyses were performed, adjusting for additional covariates to compare the effect of CZP with and without nurse assistance on hospitalization and total health care costs. Results: Patients with at least 12 months of continuous enrollment post-index date were evaluated for adherence to CZP (n=276 in each cohort). The mean and median PDC and MPR values were higher

By 1983, Taiwan had reached the final stage of its population transition, with both mortality and fertility at low rates. Such demographic change will increasingly affect the capacity of families to maintain their caregiving role. Due to reduced fertility, by the 21 st century, many elderly persons may have few or no children available to care for them in old age. This article focuses on the family network as a potential source of support for Taiwanese elderly, using microsimulation techniques. The results indicate that the proportion of aged parents without working-age children can be expected to rise substantially. The decline in fertility that has already occurred will reduce the extent of children available to share parental support obligations and increase the support burden on individual offspring. As a result continued dependence on children as the major form of support will leave a substantial proportion of elderly without resources and a large proportion of the younger generation with difficult financial burdens.

By 1983, Taiwan had reached the final stage of its population transition, with both mortality and fertility at low rates. Such demographic change will increasingly affect the capacity of families to maintain their caregiving role. Due to reduced fertility, by the 21 st century, many elderly persons may have few or no children available to care for them in old age. This article focuses on the family network as a potential source of support for Taiwanese elderly, using microsimulation techniques. The results indicate that the proportion of aged parents without working-age children can be expected to rise substantially. The decline in fertility that has already occurred will reduce the extent of children available to share parental support obligations and increase the support burden on individual offspring. As a result continued dependence on children as the major form of support will leave a substantial proportion of elderly without resources and a large proportion of the younger generation with difficult financial burdens.

By 1983, Taiwan had reached the final stage of its population transition, with both mortality and fertility at low rates. Such demographic change will increasingly affect the capacity of families to maintain their caregiving role. Due to reduced fertility, by the 21 st century, many elderly persons may have few or no children available to care for them in old age. This article focuses on the family network as a potential source of support for Taiwanese elderly, using microsimulation techniques. The results indicate that the proportion of aged parents without working-age children can be expected to rise substantially. The decline in fertility that has already occurred will reduce the extent of children available to share parental support obligations and increase the support burden on individual offspring. As a result continued dependence on children as the major form of support will leave a substantial proportion of elderly without resources and a large proportion of the younger generation with difficult financial burdens.

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Context: Americans express a strong preference for participating in decisions regarding their medical care, yet they are often unable to participate in decision-making regarding their end-of-life care. Objective: To examine determinants of end-of-life planning; including, the effect of an individual's ageing and dying process, health status and socio-economic and racial/ethnic background. Methods: US observational cohort study, using data from the Health and Retirement Study (1992 – 2014) including 37,494 individuals. Random-effects logistic regression analysis was used to examine the relationship between the presence of a living will and a range of individual time-varying characteristics, including time to death, and several time-invariant characteristics. Results: End-of-life planning depends on several patient characteristics and circumstances, with socio-economic and racial/ethnic background having the largest effects. The probability of having a living will rises sharply late in life, as we would expect, and is further modified by the patient's proximity to death. The dying process, exerts a stronger influence on end-of-life planning than does the aging. Conclusions: Understanding differences that increase end-of-life planning is important to incentivize patients’ participation. Advance planning should be encouraged and accessible to people of all ages as it is inevitable for the provision of patient-centered and cost-effective care.