Publications by authors named "Rider C"

Background: Mounting evidence links exposure to traffic-related air pollution (TRAP) to impairment in cognitive functioning.

Objectives: To determine if short-term, controlled exposure to diesel exhaust (DE) adversely affects one or more cognitive function domains.

Methods: We carried out a double-blinded crossover design with 28 healthy, adult volunteers.

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Ortho-phthalates (herein referred to as phthalates) are synthetic chemicals used in thousands of different everyday products and materials. Nearly ubiquitous environmental exposure is reflected by phthalate metabolites in the urine of almost all Canadians. However, phthalate exposure tends to be higher amongst people of low socioeconomic status and ethnic minorities.

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Objective: Evaluate a precision medicine approach to confirm a tentative diagnosis of fatal malignant hyperthermia (MH) in isoflurane-anesthetized pet dogs by identifying novel risk variants in known MH susceptibility genes.

Study Design: Retrospective case series.

Animals: A male Pit Bull mix aged 7 years (case #1), a male Golden Retriever aged 12 months (case #2) and the dam and sire of case #2.

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The Cramer classification scheme has emerged as one of the most extensively-adopted predictive toxicology tools, owing in part to its employment for chemical categorisation within threshold of toxicological concern evaluation. The characteristics of several of its rules have contributed to inconsistencies with respect to degree of hazard attributed to common (particularly food-relevant) substances. This investigation examines these discrepancies, and their origins, raising awareness of such issues amongst users seeking to apply and/or adapt the rule-set.

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One of the most pressing issues in global health is air pollution. Emissions from traffic-related air pollution and biomass burning are two of the most common sources of air pollution. Diesel exhaust (DE) and wood smoke (WS) have been used as models of these pollutant sources in controlled human exposure (CHE) experiments.

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Background: The field of toxicology has witnessed substantial advancements in recent years, particularly with the adoption of new approach methodologies (NAMs) to understand and predict chemical toxicity. Class-based methods such as clustering and classification are key to NAMs development and application, aiding the understanding of hazard and risk concerns associated with groups of chemicals without additional laboratory work. Advances in computational chemistry, data generation and availability, and machine learning algorithms represent important opportunities for continued improvement of these techniques to optimize their utility for specific regulatory and research purposes.

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Background: The National Institute of Environmental Health Sciences (NIEHS) continues to prioritize research to better understand the health effects resulting from exposure to mixtures of chemical and nonchemical stressors. Mixtures research activities over the last decade were informed by expert input during the development and deliberations of the 2011 NIEHS Workshop "Advancing Research on Mixtures: New Perspectives and Approaches for Predicting Adverse Human Health Effects." NIEHS mixtures research efforts since then have focused on key themes including ) prioritizing mixtures for study, ) translating mixtures data from and studies, ) developing cross-disciplinary collaborations, ) informing component-based and whole-mixture assessment approaches, ) developing sufficient similarity methods to compare across complex mixtures, ) using systems-based approaches to evaluate mixtures, and ) focusing on management and integration of mixtures-related data.

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The evidence associating traffic-related air pollution (TRAP) with allergic asthma is growing, but the underlying mechanisms for this association remain unclear. The airway epithelium is the primary tissue exposed to TRAP, hence understanding its interactions with TRAP and allergen is important. Diesel exhaust (DE), a paradigm of TRAP, consists of particulate matter (PM) and gases.

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Traffic-related air pollution (TRAP) exposure is associated with systemic health effects, which can be studied using blood-based markers. Although we have previously shown that high TRAP concentrations alter the plasma proteome, the concentration-response relationship between blood proteins and TRAP is unexplored in controlled human exposure studies. We aimed to identify concentration-dependent plasma markers of diesel exhaust (DE), a model of TRAP.

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Article Synopsis
  • * The new analysis utilized a nearly doubled dataset and implemented a Bayesian statistical model, providing a more reliable and unbiased assessment of the potency of specific compounds with accompanying uncertainty estimates.
  • * The updated TEFs predict lower total toxic equivalents in analyzed human milk and seafood when compared to the 2005 TEFs, except for mono-ortho PCBs, which retained their earlier values due to insufficient data.
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Background: Personal care products (PCPs) contain many different compounds and are a source of exposure to endocrine disrupting chemicals (EDCs), including phthalates and phenols. Early-life exposure to EDCs commonly found in PCPs has been linked to earlier onset of puberty.

Objective: To characterize the human and animal evidence on the association between puberty-related outcomes and exposure to PCPs and their chemical constituents and, if there is sufficient evidence, identify groups of chemicals and outcomes to support a systematic review for a class-based hazard or risk assessment.

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Consumers have unprecedented access to botanical dietary supplements through online retailers, making it difficult to ensure product quality and authenticity. Therefore, methods to survey and compare chemical compositions across botanical products are needed. Nuclear magnetic resonance (NMR) spectroscopy and non-targeted mass spectrometry (MS) were used to chemically analyze commercial products labeled as containing one of three botanicals: blue cohosh, goldenseal, and yohimbe bark.

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Human health risk assessments for complex mixtures can address real-world exposures and protect public health. While risk assessors typically prefer whole mixture approaches over component-based approaches, data from the precise exposure of interest are often unavailable and surrogate data from a sufficiently similar mixture(s) are required. This review describes recent advances in determining sufficient similarity of whole, complex mixtures spanning the comparison of chemical features, bioactivity profiles, and statistical evaluation to determine "thresholds of similarity".

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Interest in botanicals, particularly as dietary supplement ingredients, is growing steadily. This growth, and the marketing of new ingredients and combination products as botanical dietary supplements, underscores the public health need for a better understanding of potential toxicities associated with use of these products. This article and accompanying template outline the resources to collect literature and relevant information to support the design of botanical toxicity studies.

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N-butylbenzenesulfonamide (NBBS) is a high-production volume plasticizer that is an emerging contaminant of concern for environmental and human health. To understand the risks and health effects of exposure to NBBS, studies were conducted in adult-exposed mice and developmentally exposed rats to evaluate the potential for NBBS to modulate the immune system. Beginning between 8 and 9 weeks of age, dosed feed containing NBBS at concentrations of 0, 313, 625, 1250, 2500, and 5000 ppm was continuously provided to B6C3F1/N female mice for 28 days.

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Objective: Describe, and assess disparities in, the changes in Supplemental Nutrition Assistance Program Education (SNAP-Ed) that occurred the year before vs. the year when COVID-19 restrictions were implemented.

Design: Observational study comparing reach, intensity, and dose of California Local Health Department (LHD) SNAP-Ed interventions in Federal Fiscal years 2019 and 2020 (FFY19, FFY20).

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Osteoid osteomas are benign bone tumors that are commonly found in the cortical segments of long bone but can occasionally occur in the talus of the foot. They typically present in younger males and are characterized by lesions with a vascularized nidus surrounded by sclerotic bone. Plain radiographs can often miss the diagnosis, requiring further imaging with computed tomography (CT) or magnetic resonance imaging (MRI).

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Cookstove emissions are a significant source of indoor air pollution in developing countries and rural communities world-wide. Considering that many research sites for evaluating cookstove emissions and interventions are remote and require potentially lengthy periods of particulate matter (PM) filter sample storage in sub-optimal conditions (e.g.

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Air pollution exposure is harmful to human airways, and its impacts are best studied using concentration-response relationships. However, most concentration-response research on airway health has investigated chronic exposures, with less being known about acute effects, which can be robustly studied using controlled human exposures. To investigate the concentration relationship between airway health measures and diesel exhaust (DE).

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This paper examines discussions of women's and men's reproductive aging in a series of western European medical texts written in the period 1100-1300. It uses the modern image of the biological clock to explore how far physicians in earlier periods understood reproductive aging to be a process of slow decline before a final age at which fertility ended (menopause for women, or a less defined 'old age' for men), and how far they viewed women's reproductive aging as different from men's. The article argues that, in contrast to modern medical and popular understandings, medieval physicians assumed men and women were broadly fertile up to a final cut-off point, and had little interest in viewing age-related fertility decline as a slow process beginning well before menopause.

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Background: Traffic-related air pollution (TRAP) exposure causes adverse effects on wellbeing and quality of life, which can be studied non-invasively using self-reported symptoms. However, little is known about the effects of different TRAP concentrations on symptoms following controlled exposures, where acute responses can be studied with limited confounding. We investigated the concentration-response relationship between diesel exhaust (DE) exposure, as a model TRAP, and self-reported symptoms.

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The lung microbiome plays a crucial role in airway homeostasis, yet we know little about the effects of exposures such as air pollution therein. We conducted a controlled human exposure study to assess the impact of diesel exhaust (DE) on the human airway microbiome. Twenty-four participants (former smokers with mild to moderate COPD (N = 9), healthy former smokers (N = 7), and control healthy never smokers (N = 8)) were exposed to DE (300 μg/m PM) and filtered air (FA) for 2 h in a randomized order, separated by a 4-week washout.

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Botanicals can cause nephrotoxicity via numerous mechanisms, including disrupting renal blood flow, damaging compartments along the nephron, and obstructing urinary flow. While uncommon, there are various reports of botanical-induced nephrotoxicity in the literature, such as from aristolochia ( and rhubarb (.).

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In the real world, individuals are exposed to chemicals from sources that vary over space and time. However, traditional risk assessments based on in vivo animal studies typically use a chemical-by-chemical approach and apical disease endpoints. New approach methodologies (NAMs) in toxicology, such as in vitro high-throughput (HTS) assays generated in Tox21 and ToxCast, can more readily provide mechanistic chemical hazard information for chemicals with no existing data than in vivo methods.

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