Publications by authors named "Juleen Lam"

Environmental exposures, including widespread industrial pollution, impact human health and are amplified in more highly exposed communities. Policy and regulatory frameworks for making decisions and recommendations on interventions to mitigate or prevent exposures tend to narrowly focus on exposure and some health-related data related to risks. Typically, such frameworks do not consider other factors, including essentiality, health equity, and distribution of benefits and costs.

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While high-throughput (HTP) assays have been proposed as platforms to rapidly assess reproductive toxicity, there is currently a lack of established assays that specifically address germline development/function and fertility. We assessed the applicability domains of yeast (S. cerevisiae) and nematode (C.

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Infertility affects ∼12 % of couples, with environmental chemical exposure as a potential contributor. Of the chemicals that are actively manufactured, very few are assessed for reproductive health effects. Rodents are commonly used to evaluate reproductive effects, which is both costly and time consuming.

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Article Synopsis
  • Scientists are studying how certain chemicals can harm reproduction, but there aren't many quick tests to check this yet.
  • They looked at how well tests using yeast and tiny worms could find toxic chemicals and compared their results with a database of mammal data.
  • The tests showed good agreement in identifying harmful substances, suggesting these tests could help quickly find chemicals that affect reproduction in the future.
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Background: Multiple lines of evidence suggest that exposure to per- and polyfluoroalkyl substances (PFAS) may alter glucose homeostasis, particularly during pregnancy, and may affect risk for developing gestational diabetes mellitus (GDM). While previous systematic reviews have been conducted on this topic, they did not assess internal validity of the included studies and their search strategies were narrowly focused.

Objective: The objective of this study is to assess the effect of higher PFAS exposure (defined by individual compounds or mixtures measured before or during pregnancy) on GDM and subclinical measures of impaired glucose homeostasis (measured during pregnancy) compared to lower PFAS exposure in pregnant.

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Reproduction is a functional outcome that relies on complex cellular, tissue, and organ interactions that span the developmental period to adulthood. Thus, the assessment of its disruption by environmental chemicals would benefit significantly from scalable and innovative approaches to testing using functionally comparable reproductive models such as the nematode C. elegans.

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Article Synopsis
  • Reproduction involves a lot of complex interactions between cells, tissues, and organs from early development to adulthood.
  • Testing how environmental chemicals affect reproduction is difficult with traditional methods because there are so many chemicals to check.
  • A study found 13 harmful chemicals for reproduction, especially certain disinfectants called Quaternary Ammonium Compounds (QACs), showing the importance of using faster testing methods for these kinds of chemicals.
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Article Synopsis
  • The global production of industrial chemicals is rising, leading to health risks and disproportionate impacts on low-wealth and communities of color.
  • Multiple health organizations are urging improved regulations to protect against harmful exposures.
  • A set of five consensus recommendations aims to enhance EPA policies, emphasizing accountability for chemical producers, recognizing potential hazards even without data, better protecting at-risk populations, reevaluating assumptions about "safe" exposure levels, and addressing conflicts of interest in risk assessments.
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Human health risk assessment currently uses the reference dose or reference concentration (RfD, RfC) approach to describe the level of exposure to chemical hazards without appreciable risk for non-cancer health effects in people. However, this "bright line" approach assumes that there is minimal risk below the RfD/RfC with some undefined level of increased risk at exposures above the RfD/RfC and has limited utility for decision-making. Rather than this dichotomous approach, non-cancer risk assessment can benefit from incorporating probabilistic methods to estimate the amount of risk across a wide range of exposures and define a risk-specific dose.

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Background: Exposure to endocrine disrupting chemicals such as bisphenol A (BPA) is primarily from the diet through canned foods. Characterizing dietary exposures can be conducted through biomonitoring and dietary surveys; however, these methods can be time-consuming and challenging to implement.

Methods: We developed a novel dietary exposure risk questionnaire to evaluate BPA exposure and compared these results to 24-hr dietary recall data from participants (n = 404) of the Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) study, a dietary clinical trial, to validate questionnaire responses.

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Tobacco smoking continues to cause considerable premature mortality and morbidity worldwide. Most of the approximately six trillion cigarettes sold globally each year are discarded improperly as toxic environmental waste. Tobacco product waste, including cigarette butts, is the most commonly collected waste item worldwide.

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Article Synopsis
  • The text discusses the need for a thorough evaluation of available evidence to assess potential human health risks from various environmental agents, emphasizing the importance of integrating data from different sources in risk assessments.
  • It summarizes key discussions from an international workshop involving experts from different sectors who aimed to develop an evidence-based risk assessment framework that accurately reflects human health risks and uncertainties.
  • While the workshop did not aim for complete consensus, participants generally agreed on important considerations for incorporating modern scientific approaches into risk assessment, leading to the creation of a prototype framework for further exploration.
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This letter responds to the US Environmental Protection Agency's Integrated Risk Information System (IRIS) program letter by Radke et al. (2021) that was published in response to the application of the IRIS risk of bias tool in our recent study "Assessing risk of bias in human environmental epidemiology studies using three tools: different conclusions from different tools." Their letter stated that we misrepresented the IRIS approach.

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The workshop titled “Application of evidence-based methods to construct mechanism-driven chemical assessment frameworks” was co-organized by the Evidence-based Toxicology Collaboration and the European Food Safety Authority (EFSA) and hosted by EFSA at its headquarters in Parma, Italy on October 2 and 3, 2019. The goal was to explore integration of systematic review with mechanistic evidence evaluation. Participants were invited to work on concrete products to advance the exploration of how evidence-based approaches can support the development and application of adverse outcome pathways (AOP) in chemical risk assessment.

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Objective: Scientific evidence related to environmental exposures continues to mount. Tools such as evidence mapping support decision making, but can be resource- and time-intensive. We explored "rapid evidence mapping" to efficiently map scientific evidence using rigorous and transparent methodologies.

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Restaurant delivery services have gained in popularity among college students; however, students participating in the Supplemental Nutrition Assistance Program (SNAP) are not allowed to redeem their benefits via restaurant delivery services. This mixed-methods head-to-head crossover trial assessed whether college students experiencing marginal food security prefer benefits via a grocery store gift card (as a proxy for traditional SNAP benefits) or via a restaurant delivery service gift card of equivalent value, and which type of benefit is more effective at improving food security status. Thirty college students experiencing marginal food security were recruited to receive $80 in cash equivalent benefits to spend over a two-month period in the form of grocery store gift cards and restaurant delivery service gift cards.

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Systematic reviews are routinely used to synthesize current science and evaluate the evidential strength and quality of resulting recommendations. For specific events, such as rare acute poisonings or preliminary reports of new drugs, we posit that case reports/studies and case series (human subjects research with no control group) may provide important evidence for systematic reviews. Our aim, therefore, is to present a protocol that uses rigorous selection criteria, to distinguish high quality case reports/studies and case series for inclusion in systematic reviews.

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Background: Synthesizing environmental health science is crucial to taking action to protect public health. Procedures for evidence evaluation and integration are transitioning from "expert-based narrative" to "systematic" review methods. However, little is known about the methodology being utilized for either type of review.

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Background: Every major federal regulation in the United States requires an economic analysis estimating its benefits and costs. Benefit-cost analyses related to regulations on formaldehyde exposure have not included asthma in part due to lack of clarity in the strength of the evidence.

Objectives: 1) To conduct a systematic review of evidence regarding human exposure to formaldehyde and diagnosis, signs, symptoms, exacerbations, or other measures of asthma in humans; and 2) quantify the annual economic benefit for decreases in formaldehyde exposure.

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Objective: Food security status is a continuum ranging from high to very low food security. While marginal food security falls next to high food security on the spectrum, new quantitative research indicates marginal food security status is associated with negative health outcomes and poor academic performance among college students. Qualitative research focusing on college students experiencing marginal food security has not been conducted.

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Low birth weight is an important risk factor for many co-morbidities both in early life as well as in adulthood. Numerous studies report associations between prenatal exposure to particulate matter (PM) air pollution and low birth weight. Previous systematic reviews and meta-analyses report varying effect sizes and significant heterogeneity between studies, but did not systematically evaluate the quality of individual studies or the overall body of evidence.

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Given the worldwide spread of the 2019 Novel Coronavirus (COVID-19), there is an urgent need to identify risk and protective factors and expose areas of insufficient understanding. Emerging tools, such as the Rapid Evidence Map (rEM), are being developed to systematically characterize large collections of scientific literature. We sought to generate an rEM of risk and protective factors to comprehensively inform areas that impact COVID-19 outcomes for different sub-populations in order to better protect the public.

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Background: Systematic reviews are increasingly prevalent in environmental health due to their ability to synthesize evidence while reducing bias. Different systematic review methods have been developed by the US National Toxicology Program's Office of Health Assessment and Translation (OHAT), the US Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS), and by the US EPA under the Toxic Substances Control Act (TSCA), including the approach to assess risk of bias (ROB), one of the most vital steps which is used to evaluate internal validity of the studies. Our objective was to compare the performance of three tools (OHAT, IRIS, TSCA) in assessing ROB.

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Introduction: Human cytochrome p450 (CYP) enzyme expression and activity is lower in the fetus as compared to the adult; however, limited quantitative data exists regarding the specific differences in magnitude or the degree of inducibility due to environmental factors.

Methods: We utilized a combination of in silico- and molecular-based approaches to profile and compare CYP expression/activity in human adult liver and fetal tissues. Using public datasets, we evaluated human CYP expression between: 1) placenta vs.

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