Performance of commercially available soil amendments for enhanced Cu attenuation in bioretention media.

Bioretention structures such as planter boxes, swales and rain gardens are being increasingly utilized in built landscapes as a strategy to attenuate both stormwater flows and contaminant loads. Copper (Cu) roofing materials contribute significantly higher mass loads of dissolved Cu per unit area than other surfaces such as parking lots and roadways. While a recent study demonstrated that conventional bioretention media can remove greater than 90% of Cu from copper roof runoff, the median Cu concentrations at the point of discharge from bioretention structures (66 µg L-1) still did not achieve Cu concentrations in stormwater discharges sought in some jurisdictions (for example, < 14 µg L-1). Consequently, commercially available soil amendments were assessed to improve bioretention Cu removal. The ability of biochar, greensand, and zeolite to improve Cu removal was evaluated in laboratory column studies. Additionally, the performance of zeolite as an underlayer amendment was evaluated in bioretention planter boxes treating stormwater from a picnic shelter with a partitioned copper roof. Cu was measured in the planter box influent and effluent. The field setup included 2 control planter boxes containing only standard bioretention media and 2 amended with the zeolite underlayer. Samples from ten storms were collected with flow-weighted composite sampling. Total Cu in composite samples of the influent waters ranged from 445 to 1683 µg L-1 and had a median concentration of 934 µg L-1. Total Cu in the effluent from the control planter boxes ranged from 10 to 64 µg L-1, with a mean of 29 µg L-1. Total Cu in effluent from the zeolite amended planter boxes ranged from 4 to 44 µg L-1 with a mean of 18 µg L-1. Attenuation in the control planter boxes ranged from 90 to 99% with a median of 93.4% by concentration and ranged from 95 to 99% with a median of 97.5% in the zeolite amended planter boxes.

Influence of Modern Stormwater Management Practices on Transport of Road Salt to Surface Waters.

Application of road salts in regions with colder climates is leading to ground and surface water contamination. However, we know little about how modern stormwater management practices affect the movement of road salt through urban watersheds. We investigated groundwater contamination and transport of road salts at two stormwater ponds in Baltimore County, Maryland. In association with the ponds, we documented a plume of contaminated groundwater that resulted in Cl- loadings to the adjacent stream of 6574 to 40 008 kg Cl- per winter, depending on winter snowfall. We also monitored Na+ and Cl- ion concentrations and the temporal dynamics of conductivity at a range of stream sites in watersheds with and without stormwater management ponds. Streams draining watersheds with stormwater ponds had consistently higher conductivities and Cl- concentrations during base flow conditions and often exhibited greater peaks in Cl- and conductivity associated with winter storms and subsequent melting events, despite the degree of watershed development. Our results indicate that modern stormwater management practices are not protecting surface waters from road salt contamination and suggest they create contaminated plumes of groundwater that deliver Cl- and Na+ to streams throughout the year.

In vivo proximity labeling for the detection of protein-protein and protein-RNA interactions.

Accurate and sensitive detection of protein-protein and protein-RNA interactions is key to understanding their biological functions. Traditional methods to identify these interactions require cell lysis and biochemical manipulations that exclude cellular compartments that cannot be solubilized under mild conditions. Here, we introduce an in vivo proximity labeling (IPL) technology that employs an affinity tag combined with a photoactivatable probe to label polypeptides and RNAs in the vicinity of a protein of interest in vivo. Using quantitative mass spectrometry and deep sequencing, we show that IPL correctly identifies known protein-protein and protein-RNA interactions in the nucleus of mammalian cells. Thus, IPL provides additional temporal and spatial information for the characterization of biological interactions in vivo.

Diabetes among Latinos in the Southwestern United States: border health and binational cooperation.

This analysis reviews cooperation between the four border states of the United States of America (Arizona, California, New Mexico, and Texas) and international partners in Mexico with regard to type 2 diabetes among Latinos. Binational cooperation, academic collaboration, preventative health initiatives, and efforts to improve health care access for the border population are highlighted. This meta-analysis of the literature points out causative factors of the increased type 2 diabetes prevalence among Latinos in the United States; an inverse correlation between diabetes and education and socioeconomic level; contributing factors, including barriers with language, health care payment, transportation, and underestimating diabetes implications; and a lack of social and environmental support for disease management. Medical and indirect costs in socioeconomic terms are also included. Cooperation between the United States and Mexico may be beneficial to promoting further collaborative efforts between these nations, and serve as a template for greater cooperative efforts to mitigate the substantial public health and socioeconomic implications of type 2 diabetes globally.

Quantification of the plasma clearance kinetics of a gadolinium-based contrast agent by photoinduced triplet harvesting.

The use of gadolinium-based contrast agents (GBCA) is integral to the field of diagnostic magnetic resonance imaging (MRI). Pharmacokinetic evaluation of the plasma clearance of GBCA is required for all new agents or improved formulations, to address concerns over toxicity or unforeseen side effects. Current methods to measure GBCA in plasma lack either a rapid readout or the sensitivity to measure small samples or require extensive processing of plasma, all obstacles in the development and characterization of new GBCA. Here, we quantify the plasma concentration of a labeled analogue of a common clinical GBCA by ligand triplet harvesting and energy transfer. The nonemittive GBCA becomes a "dark donor" to a fluorescent detector molecule, with a lower limit of detection of 10(-7) M in unprocessed plasma. On a time scale of minutes, we determine the plasma clearance rate in the wild-type mouse, using time-resolved fluorescence on a standard laboratory plate reader.

Lethal and sublethal effects of embryonic and larval exposure of Hyla versicolor to Stormwater pond sediments.

Stormwater ponds are common features of modern stormwater management practices. Stormwater ponds often retain standing water for extended periods of time, develop vegetative characteristics similar to natural wetlands, and attract wildlife. However, because stormwater ponds are designed to capture pollutants, wildlife that utilize ponds might be exposed to pollutants and suffer toxicological effects. To investigate the toxicity of stormwater pond sediments to Hyla versicolor, an anuran commonly found using retention ponds for breeding, we exposed embryos and larvae to sediments in laboratory microcosms. Exposure to pond sediments reduced survival of embryos by approximately 50% but did not affect larval survival. Larvae exposed to stormwater pond sediment developed significantly faster (x = 39 days compared to 42 days; p = 0.005) and were significantly larger at metamorphosis (x = 0.49 g compared to 0.36 g; p < 0.001) than controls that were exposed to clean sand. Substantial amounts (712-2215 mg/l) of chloride leached from pond sediments into the water column of treatment microcosms; subsequently, survival of embryos was negatively correlated (r (2) = 0.50; p < 0.001) with water conductivity during development. Our results, along with the limited number of other toxicological studies of stormwater ponds, suggest that road salt contributes to the degradation of stormwater pond habitat quality for amphibian reproduction and that future research should focus on understanding interactions among road salts and other pollutants and stressors characteristic of urban environments.

Dentoalveolar trauma in the pediatric population.

BACKGROUND: Dental alveolar trauma in pediatric patients is a challenge to health care professionals. It can lead to early tooth loss that can compromise oral function, aesthetics, and self-esteem and alter the long-term plan of care for the pediatric patient. METHODS: The authors reviewed the literature pertaining to pediatric dental and alveolar traumas. The current etiology, incidence, classifications of injury, and methods to diagnose and treat these patients were reviewed and outlined. CONCLUSIONS: Management of dental trauma is complex and requires a comprehensive and accurate diagnostic and treatment plan. It is also important to consider the biologic, functional, aesthetic, and economic aspects, as well as the patient's desire. Physicians who provide primary care for children have a unique position to provide diagnostic, triage, educational, and preventive dental care for patients. Several articles have been published regarding primary pediatricians' participation in the preventive dental health care of their patients. One publication, a survey of physicians in Alabama focusing on physicians' overall awareness of dental issues, concluded that most physicians believe they have a role in the oral health of their patients. Most were not aware of many of the American Academy of Pediatric Dentistry's recommendations.

Effects of zinc exposure on earthworms, Lumbricus terrestris, in an artificial soil.

Earthworms have the potential to act as trophic links for pollutants that accumulate in urban soils. However, many pollutants may act as micronutrients at low concentrations and toxins at higher concentration. When pollutants are also micronutrients, bioaccumulations may initially increase trophic transfer as pollutant concentration increase, but at higher levels toxic effects may limit population size and the potential for trophic transfer. We found support for this model among earthworms exposed to a range of soil Zn levels. Worms showed increasing bioaccumulation of Zn with increasing Zn soil concentrations, but at higher Zn levels worm growth rates decreased.

Expanding the repertoire of small molecule transcriptional activation domains.

Molecules that can reconstitute the function of transcriptional activators hold enormous potential as therapeutic agents and as mechanistic probes. Previously we described an isoxazolidine bearing functional groups similar to natural transcriptional activators that up-regulates transcription 80-fold at 1 microM in cell culture. In this study, we analyze analogs of this molecule to define key characteristics of small molecules that function as transcriptional activation domains in cells. Conformational rigidity is an important contributor to function as is an overall amphipathic substitution pattern. Using these criteria, we identified additional molecular scaffolds with excellent (approximately 60-fold) activity as transcriptional activation domains. These results point the way for the creation of new generations of small molecules with this function.

Microcosm investigations of stormwater pond sediment toxicity to embryonic and larval amphibians: variation in sensitivity among species.

Stormwater ponds have become common features of modern development and often represent significant amounts of open space in urbanized areas. Although stormwater ponds may provide habitat for wildlife, factors responsible for producing variation in wildlife use of ponds have received limited attention. To investigate the role of variation in species tolerances of pollutants in structuring pond-breeding amphibian assemblages, we exposed species tolerant (Bufo americanus) and not tolerant (Rana sylvatica) of urbanization to pond sediments in laboratory microcosms. Pond microcosms had elevated sediment metal levels and chloride water concentrations. Among R. sylvatica embryos, exposure to pond sediments resulted in 100% mortality. In contrast, B. americanus embryos and larvae experienced only sublethal effects (i.e., reduced size at metamorphosis) due to pond sediment exposure. Our results suggest variation in pollutant tolerance among early developmental stages of amphibians may act in concert with terrestrial habitat availability to structure amphibian assemblages associated with stormwater ponds.

Bioretention storm water control measures decrease the toxicity of copper roof runoff.

The present study evaluated the ability of 2 different bioretention storm water control measures (SCMs), planter boxes and swales, to decrease the toxicity of sheet copper (Cu) roofing runoff to Daphnia magna. The present study quantified changes in storm water chemistry as it passed through the bioretention systems and utilized the biotic ligand model (BLM) to assess whether the observed D. magna toxicity could be predicted by variations found in water chemistry. Laboratory toxicity tests were performed using select storm samples with D. magna cultured under low ionic strength conditions that were appropriate for the low ionic strength of the storm water samples being tested. The SCMs decreased toxicity of Cu roof runoff in both the BLM results and the storm water bioassays. Water exiting the SCMs was substantially higher than influent runoff in pH, ions, alkalinity, and dissolved organic carbon and substantially lower in total and dissolved Cu. Daphnids experienced complete mortality in untreated runoff from the Cu roof (the SCM influent); however, for planter and swale effluents, survival averaged 86% and 95%, respectively. The present study demonstrated that conventional bioretention practices, including planter boxes and swales, are capable of decreasing the risk of adverse effects from sheet Cu roof runoff to receiving systems, even before considering dilution of effluents in those receiving systems and associated further reductions in copper bioavailability. Environ Toxicol Chem 2017;36:1680-1688. © 2016 SETAC.

Attenuation of copper in runoff from copper roofing materials by two stormwater control measures.

Concerns have been raised over diffuse and non-point sources of metals including releases from copper (Cu) roofs during storm events. A picnic shelter with a partitioned Cu roof was constructed with two types of stormwater control measures (SCMs), bioretention planter boxes and biofiltration swales, to evaluate the ability of the SCMs to attenuate Cu in stormwater runoff from the roof. Cu was measured as it entered the SCMs from the roof as influent as well as after it left the SCMs as effluent. Samples from twenty-six storms were collected with flow-weighted composite sampling. Samples from seven storms were collected with discrete sampling. Total Cu in composite samples of the influent waters ranged from 306 to 2863 µg L(-1) and had a median concentration of 1087 µg L(-1). Total Cu in the effluent from the planter boxes ranged from 28 to 141 µg L(-1), with a median of 66 µg L(-1). Total Cu in effluent from the swales ranged from 7 to 51 µg L(-1) with a median of 28 µg L(-1). Attenuation in the planter boxes ranged from 85 to 99% with a median of 94% by concentration and in the swales ranged from 93 to 99% with a median of 99%. As the roof aged, discrete storm events showed a pronounced first-flush effect of Cu in SCM influent but this was less pronounced in the planter outlets. Stormwater retention time in the media varied with antecedent conditions, stormwater intensity and volume with median values from 6.6 to 73.5 min. Based on local conditions, a previously-published Cu weathering model gave a predicted Cu runoff rate of 2.02 g m(-2) yr(-1). The measured rate based on stormwater sampling was 2.16 g m(-2) yr(-1). Overall, both SCMs were highly successful at retaining and preventing offsite transport of Cu from Cu roof runoff.

An enriched stable isotope technique to estimate the availability of soil zinc to Lumbricus terrestris (L.) across a salinization gradient.

An enriched stable isotope approach was developed to evaluate Zn bioavailability to Lumbricus terrestris. The decrease in (68)Zn/(66) Zn in organ tissues was used to assess the relative magnitude of the bioavailable soil Zn pool. This tool was then used to specifically evaluate bioavailability as a function of soil cation distribution. Storm-water pond soils were modified using two treatment regimens whereby H(2)O-extractable Zn was varied either by different ZnCl(2) amendments or by constant ZnCl(2) amendment followed by varying the soil cation distribution through salt amendments (NaCl or CaCl(2)). Earthworms previously equilibrated in (68) Zn-spiked soil were introduced to experimental soils, and after 2 d, removed for analysis of isotopic ratios in specific tissues. Despite a wide range of H(2)O-extractable Zn values produced by the salt treatments (0.007-24.3 mg/kg), a significant relationship between Zn turnover rate in earthworm tissues and H(2)O-extractable Zn in the salt-treated soils was not observed. Rather, considering both treatment regimens, turnover rate better correlated with Zn present in broader pools, such as that extracted by 6M HNO(3). The bioavailability of trace metals to earthworms may be poorly characterized by loosely bound fractions such as the pore water. Additionally, the turnover rate of (68)Zn in anterior organ tissues may be an effective tool to evaluate the relative magnitude of the bioavailable soil Zn pool.

Chemical fractionation of Cu and Zn in stormwater, roadway dust and stormwater pond sediments.

This study evaluated the chemical fractionation of Cu and Zn from source to deposition in a stormwater system. Cu and Zn concentrations and chemical fractionation were determined for roadway dust, roadway runoff and pond sediments. Stormwater Cu and Zn concentrations were used to generate cumulative frequency distributions to characterize potential exposure to pond-dwelling organisms. Dissolved stormwater Zn exceeded USEPA acute and chronic water quality criteria in approximately 20% of storm samples and 20% of the storm duration sampled. Dissolved Cu exceeded the previously published chronic criterion in 75% of storm samples and duration and exceeded the acute criterion in 45% of samples and duration. The majority of sediment Cu (92-98%) occurred in the most recalcitrant phase, suggesting low bioavailability; Zn was substantially more available (39-62% recalcitrant). Most sediment concentrations for Cu and Zn exceeded published threshold effect concentrations and Zn often exceeded probable effect concentrations in surface sediments.

Diabetes among Latinos in the Southwestern United States: border health and binational cooperation / Diabetes en la población de origen latino del sudoeste de los Estados Unidos: salud fronteriza y cooperación binacional

This analysis reviews cooperation between the four border states of the United States of America (Arizona, California, New Mexico, and Texas) and international partners in Mexico with regard to type 2 diabetes among Latinos. Binational cooperation, academic collaboration, preventative health initiatives, and efforts to improve health care access for the border population are highlighted. This meta-analysis of the literature points out causative factors of the increased type 2 diabetes prevalence among Latinos in the United States; an inverse correlation between diabetes and education and socioeconomic level; contributing factors, including barriers with language, health care payment, transportation, and underestimating diabetes implications; and a lack of social and environmental support for disease management. Medical and indirect costs in socioeconomic terms are also included. Cooperation between the United States and Mexico may be beneficial to promoting further collaborative efforts between these nations, and serve as a template for greater cooperative efforts to mitigate the substantial public health and socioeconomic implications of type 2 diabetes globally.

Este análisis examina la cooperación de los cuatro estados fronterizos de los Estados Unidos de América (Arizona, California, Nuevo México y Texas) y los socios internacionales de México con respecto a la diabetes de tipo 2 en la población de origen latino. Se destacan la cooperación binacional, la colaboración académica, las iniciativas de prevención en salud, y las actividades orientadas a mejorar el acceso a la atención de salud por parte de la población de la frontera. Este metanálisis de la bibliografía señala los factores causales del aumento de la prevalencia de la diabetes de tipo 2 en la población de origen latino de los Estados Unidos; una correlación inversa entre la diabetes y el grado de formación y el nivel socioeconómico; los factores contribuyentes, incluidas las barreras relacionadas con el idioma, el pago de la atención de salud, el transporte, y la infravaloración de las consecuencias de la diabetes; y una falta de apoyo social y ambiental para el tratamiento de la enfermedad. También se incluyen los costos médicos y los indirectos en términos socioeconómicos. La cooperación entre los Estados Unidos y México - podría ser beneficiosa para promover nuevas iniciativas de colaboración entre estas naciones y servir como mo-delo a otras iniciativas más amplias de cooperación dirigidas a mitigar las sustanciales consecuencias de salud pública y socioeconómicas de la diabetes de tipo 2 a escala mundial.

Impacts of weathered tire debris on the development of Rana sylvatica larvae.

Highway runoff has the potential to negatively impact receiving systems including stormwater retention ponds where highway particulate matter can accumulate following runoff events. Tire wear particles, which contain about 1% Zn by mass, make up approximately one-third of the vehicle derived particulates in highway runoff and therefore may serve as a stressor to organisms utilizing retention ponds as habitat. In this study, we focused on the potential contribution of tire debris to Zn accumulation by Rana sylvatica larvae and possible lethal or sublethal impacts resulting from exposure to weathered tire debris during development. Eggs and larvae were exposed to aged sediments (containing either ZnCl2 or tire particulate matter, both providing nominal concentrations of 1000 mg Zn kg(-1)) through metamorphosis. Water column Zn was elevated in both the ZnCl2 and tire treatments relative to the control treatment, indicating that aging allowed Zn leaching from tire debris to occur. Tissue Zn was also elevated for the ZnCl2 and tire treatments indicating that Zn in the treatments was available for uptake by the amphibians. Exposure to both ZnCl2 and tire treatments increased the time for larvae to complete metamorphosis in comparison with controls. We also observed that the longer the organisms took to complete metamorphosis, the smaller their mass at metamorphosis. Our results indicate that Zn leached from aged tire debris is bioavailable to developing R. sylvatica larvae and that exposure to tire debris amended sediments can result in measurable physiological outcomes to wood frogs that may influence population dynamics.