On the need and speed of regulating triclosan and triclocarban in the United States.
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ABSTRACT: The polychlorinated aromatic antimicrobials triclosan and triclocarban are in widespread use for killing microorganisms indiscriminately, rapidly, and by nonspecific action. While their utility in healthcare settings is undisputed, benefits to users of antimicrobial personal care products are few to none. Yet, these latter, high-volume uses have caused widespread contamination of the environment, wildlife, and human populations. This feature article presents a timeline of scientific evidence and regulatory actions in the U.S. concerning persistent polychlorinated biocides, showing a potential path forward to judicious and sustainable uses of synthetic antimicrobials, including the design of greener and safer next-generation alternatives.
Project description:Removal of triclocarban (TCC) and triclosan (TCS) from wastewater is a function of adsorption, abiotic degradation, and microbial mineralization or transformation, reactions that are not currently controlled or optimized in the pollution control infrastructure of standard wastewater treatment. Here, we report on the levels of eight transformation products, human metabolites, and manufacturing byproducts of TCC and TCS in raw and treated sewage sludge. Two sample sets were studied: samples collected once from 14 wastewater treatment plants (WWTPs) representing nine states, and multiple samples collected from one WWTP monitored for 12 months. Time-course analysis of significant mass fluxes (α=0.01) indicate that transformation of TCC (dechlorination) and TCS (methylation) occurred during sewage conveyance and treatment. Strong linear correlations were found between TCC and the human metabolite 2'-hydroxy-TCC (r=0.84), and between the TCC-dechlorination products dichlorocarbanilide (DCC) and monochlorocarbanilide (r=0.99). Mass ratios of DCC-to-TCC and of methyl-triclosan (MeTCS)-to-TCS, serving as indicators of transformation activity, revealed that transformation was widespread under different treatment regimes across the WWTPs sampled, though the degree of transformation varied significantly among study sites (α=0.01). The analysis of sludge sampled before and after different unit operation steps (i.e., anaerobic digestion, sludge heat treatment, and sludge drying) yielded insights into the extent and location of TCC and TCS transformation. Results showed anaerobic digestion to be important for MeTCS transformation (37-74%), whereas its contribution to partial TCC dechlorination was limited (0.4-2.1%). This longitudinal and nationwide survey is the first to report the occurrence of transformation products, human metabolites, and manufacturing byproducts of TCC and TCS in sewage sludge.
Project description:BackgroundPrevious studies have suggested that hearing loss, which is highly prevalent but undertreated in older adults, may be associated with gait and physical functioning. Determining if hearing loss is independently associated with gait speed is critical toward understanding whether hearing rehabilitative interventions could help mitigate declines in physical functioning in older adults.MethodsWe analyzed cross-sectional data from the 1999 to 2002 cycles of the National Health and Nutritional Examination Survey during which participants 50-69 years (n=1180) underwent hearing and gait speed assessments. Hearing was defined by a pure tone average of hearing thresholds at 0.5-4kHz tones in the better-hearing ear. Gait speed was obtained in a timed 20-ft (6.1m) walk. Linear and logistic regression models were used to examine the association between hearing loss and gait speed while adjusting for demographic and cardiovascular risk factors. Analyses incorporated sampling weights to yield results generalizable to the U.S. population.ResultsIn a model adjusted for demographic and cardiovascular risk factors, a hearing loss was associated with slower gait speed (-0.05m/s per 25dB of hearing loss [95% CI: -0.09 to -0.02]) and an increased odds of having a gait speed <1.0m/s (OR=2.0 per 25dB of hearing loss, 95% CI: 1.2-3.3). The reduction in gait speed associated with a 25dB hearing loss was equivalent to that associated with an age difference of approximately 12 years.ConclusionsGreater hearing loss is independently associated with slower gait speed. Further studies investigating the mechanistic basis of this association and whether hearing rehabilitative interventions could affect gait and physical functioning are needed.
Project description:A robust method for characterizing the biophysical environment of terrestrial vegetation uses the relationship between Actual Evapotranspiration (AET) and Climatic Water Deficit (CWD). These variables are usually estimated from a water balance model rather than measured directly and are often more representative of ecologically-significant changes than temperature or precipitation. We evaluate trends and spatial patterns in AET and CWD in the Continental United States (CONUS) during 1980-2019 using a gridded water balance model. The western US had linear regression slopes indicating increasing CWD and decreasing AET (drying), while the eastern US had generally opposite trends. When limits to plant performance characterized by AET and CWD are exceeded, vegetation assemblages change. Widespread increases in aridity throughout the west portends shifts in the distribution of plants limited by available moisture. A detailed look at Sequoia National Park illustrates the high degree of fine-scale spatial variability that exists across elevation and topographical gradients. Where such topographical and climatic diversity exists, appropriate use of our gridded data will require sub-setting to an appropriate area and analyzing according to categories of interest such as vegetation communities or across obvious physical gradients. Recent studies have successfully applied similar water balance models to fire risk and forest structure in both western and eastern U.S. forests, arid-land spring discharge, amphibian colonization and persistence in wetlands, whitebark pine mortality and establishment, and the distribution of arid-land grass species and landscape scale vegetation condition. Our gridded dataset is available free for public use. Our findings illustrate how a simple water balance model can identify important trends and patterns at site to regional scales. However, at finer scales, environmental heterogeneity is driving a range of responses that may not be simply characterized by a single trend.
Project description:ImportanceImprovements in insurance coverage and access to care have resulted from the Affordable Care Act (ACA). However, a focus on short-term pre- to post-ACA changes may distract attention from longer-term trends in unmet health needs, and the problems that persist.ObjectiveTo identify changes from 1998 to 2017 in unmet need for physician services among insured and uninsured adults aged 18 to 64 years in the United States.Design, setting, and participantsSurvey study using 20 years of data, from January 1, 1998, to December 31, 2017, from the Centers for Disease Control and Prevention Behavioral Risk Factor Surveillance System to identify trends in unmet need for physician and preventive services.Main outcomes and measuresThe proportion of persons unable to see a physician when needed owing to cost (in the past year), having no routine checkup for those in whom a routine checkup was likely indicated (within 2 years), or failing to receive clinically indicated preventive services (in the recommended timeframe), overall and among subgroups defined by the presence of chronic illnesses and by self-reported health status. We estimated changes over time using logistic regression controlling for age, sex, race, Census region, employment status, and income.ResultsAmong the adults aged 18 to 64 years in 1998 (n = 117 392) and in 2017 (n = 282 378) who responded to the Centers for Disease Control and Prevention Behavioral Risk Factors Surveillance System (mean age was 39.2 [95% CI, 39.0-39.3]; 50.3% were female; 65.9% were white), uninsurance decreased by 2.1 (95% CI, 1.6-2.5) percentage points (from 16.9% to 14.8%). However, the adjusted proportion unable to see a physician owing to cost increased by 2.7 (95% CI, 2.2-3.8) percentage points overall (from 11.4% to 15.7%, unadjusted); by 5.9 (95% CI, 4.1-7.8) percentage points among the uninsured (32.9% to 39.6%, unadjusted) and 3.6 (95% CI, 3.2-4.0) percentage points among the insured (from 7.1% to 11.5%, unadjusted). The adjusted proportion of persons with chronic medical conditions who were unable to see a physician because of cost also increased for most conditions. For example, an increase in the inability to see a physician because of cost for patients with cardiovascular disease was 5.9% (95% CI, 1.7%-10.1%), for patients with elevated cholesterol was 3.5% (95% CI, 2.5%-4.5%), and for patients with binge drinking was 3.1% (95% CI, 2.3%-3.3%). The adjusted proportion of chronically ill adults receiving checkups did not change. While the adjusted share of people receiving guideline-recommended cholesterol tests (16.8% [95% CI, 16.1%-17.4%]) and flu shots (13.2% [95% CI, 12.7%-13.8%]) increased, the proportion of women receiving mammograms decreased (-6.7% [95% CI, -7.8 to -5.5]).Conclusions and relevanceDespite coverage gains since 1998, most measures of unmet need for physician services have shown no improvement, and financial access to physician services has decreased.
Project description:The experience of dermatological conditions such as psoriasis is different for people with skin of color (SoC) than for white individuals. The objective of this literature review was to understand challenges and unmet needs associated with access to care, diagnosis, and treatment of psoriasis among people with SoC in Canada and the United States. The review focused on studies published in the last 5 years. After screening 919 unique records, 26 studies were included. Importantly, lack of culturally competent care was identified as a key unmet need for psoriasis among people with SoC. In addition, cost of care and cultural views of psoriasis may influence decisions to seek care among people with SoC. Baseline patient characteristics in psoriasis studies and the prevalence/incidence of psoriasis vary across racial/ethnic groups, which may reflect differences in the rate and/or timing of diagnosis. The presentation of psoriasis differs across racial/ethnic groups, which may contribute to challenges in proper and timely diagnosis. Compared with white patients with psoriasis, individuals with SoC may be less familiar with and have different rates of treatment with biologic therapies for psoriasis, are more likely to be hospitalized for psoriasis, and their access to physicians may differ. Further, people with SoC are underrepresented in clinical trials of psoriasis therapies. Overall, the results of this literature review suggest that people with psoriasis and SoC face unique challenges in their disease experience. It is essential that clinicians and other stakeholders recognize and address these disparities to ensure equitable care.
Project description:The psychostimulant methamphetamine (MA) is a highly addictive drug that has surged in popularity over the last decade in North America. A burgeoning number of clandestine drug laboratories has led to dramatic increases in MA production, which have resulted in significant public health, legal and environmental problems. Current evidence indicates that exposure to MA is neurotoxic, and neuroimaging studies confirm that long-term use in humans may lead to extensive neural damage. These physiological changes are commonly associated with persistent forms of cognitive impairment, including deficits in attention, memory and executive function. In the present review, we provide a comprehensive description of the factors relating to MA use and the major health-related consequences, with an emphasis on MA-induced psychosis. It is hoped that increased knowledge of MA abuse will provide the basis for future treatment strategies.
Project description:It is generally assumed that an investment into cognitive abilities and their associated cost is particularly beneficial for long-lived species, as a prolonged lifespan allows to recoup the initial investment. However, ephemeral organisms possess astonishing cognitive abilities too. Invertebrates, for example, are capable of simple associative learning, reversal learning, and planning. How can this discrepancy between theory and evidence be explained? Using a simulation, we show that short lives can actually select for an increase in learning abilities. The rationale behind this is that when learning is needed to exploit otherwise inaccessible resources, one needs to learn fast in order to utilize the resources when constrained by short lifespans. And thus, increased cognitive abilities may evolve, not despite short lifespan, but because of it.