North Carolina Department of Environmental Quality

We seek to understand how uncertainty in spatiotemporal models of PM2.5 concentration influences exposure, equity, and health metrics in Canada. We evaluated the accuracy of seven longitudinal PM2.5 concentration data sets from 2002 to 2014 and conducted equity and health impact analysis using each. Specifically, we estimated population exposure improvements over time, exposure disparities for vulnerable subpopulations, and PM2.5-attributable mortality across several combinations of inputs. Nationally, reductions in population exposure to PM2.5 were consistently observed in all models between 2002 and 2014 in Canada, with larger reductions among subpopulations of visible minority status, suggesting that PM2.5 exposure and absolute exposure disparities improved over this period. Agreement between PM2.5 models is strongest for PM2.5-attributable mortality, whereas exposure time trends and contrasts between subpopulations differ more widely. Nationally, estimated PM2.5-attributable mortality ranged from 7,400 to 26,000 deaths in 2014 across combinations of seven PM2.5 models, four Canadian risk estimates, and counterfactuals of 0 and 2.5 μg/m3. PM2.5-attributable death estimates are sensitive to inputs of mortality risks, counterfactuals, and PM2.5 models. Improving estimates of Canadian PM2.5 exposure remains important for reducing uncertainty in health studies, particularly for accountability, equity, and epidemiological studies that rely on spatial or temporal contrasts.

Performance-based contractor prequalification allows a construction client to evaluate contractors’ past performance on similar work, improving the likelihood of high-quality work being performed. Occupational safety and health criteria are sometimes included in such prequalification criteria. What metrics are predictive of safe future work? The objectives of this research were to (1) understand best practices in safety and health performance measurement, (2) conduct an initial desktop screening of all fifty US state Departments of Transportation (DOTs) for their publicly available safety and health prequalification criteria, and (3) propose a path forward for a state DOT research inquiry to raise the level of safety and health performance of all contractors by understanding their views of the feasibility and effectiveness of a list of possible leading indicators. Lagging indicators (injury rates, experience modification rates, regulatory citations) are traditional measures; they are shown to measure past performance but are not predictive of future safe work. There is no consensus on viable leading indicators in the discipline of safety science. Seventeen state DOTs require safety metrics of some kind as part of their prequalification process. Including safety and health criteria in the prequalification process provides an opportunity to help underperforming contractors, particularly small and historically underutilized businesses, raise the quality of their site safety and health performance.

Targeted insertion (TIN) of transgenic trait cassettes has the potential to reduce timeline and cost for GM product development and commercialization. Precise genome engineering has made remarkable progress over the last several decades, particularly with the use of site-directed nucleases as core editing machinery. However, there are still many critical factors that can impact TIN efficiency including insertion site selection, nuclease optimization and expression, donor vector design, gene delivery, and stable event regeneration. Here, we develop workflows for target site sequence identification and gRNA screening for CRISPR-Cas12a system and demonstrate its successful application for TIN in maize with donor sequences up to 10 kilobase pairs (kb) in size. We first prioritize genomic regions for inserting transgenes in silico using bioinformatics tools and then test gRNA performance using a leaf protoplast transient assay. Despite its known low efficiency, we identify homology-directed repair (HDR) as the preferential pathway for directing targeted insertions of large sequences in immature embryos and demonstrate double-junction integrations at a rate of up to 4%. We further apply a molecular analysis workflow using large amplicon TaqMan assays and nanopore sequencing for streamlined identification and characterization of high-quality insertion events with intact large inserts. Analysis of TIN events across generations suggests that efficiency bottlenecks are not limited to donor targeted integration; attrition in efficiency also results from partial or additional donor insertion, chimerism, and close linkage with undesired sequence insertions such as those encoding the editing machinery. This work represents a major step forward in realizing the potential of precise genome engineering in maize for basic research and biotech trait development applications.

The remediation of Comprehensive Environmental Response, Compensation, and Liability Act or Superfund sites is limited to cleanup to levels no lower than background concentrations. However, both anthropogenically induced and naturally occurring metal concentrations in soil and sediments often complicate this cleanup process. To support informed decisions on heavy metal cleanup and the development of soil heavy metal-related policies in North Carolina, a statewide dataset of background heavy metal data from Superfund site investigations was compiled. The dataset represents background concentrations at 326 Superfund sites found in North Carolina, United States, from 1985 to 2015. This 30-year dataset comprises site location data and analytical measurement results for 18 heavy metals in 624 soil and 228 sediment samples, obtained using standard methods. The data are presented in an interactive dashboard, offering summary statistics and graphical representations that can be customized to support specific decision-making needs. The data and Dashboard serve two main goals: (1) to inform and support cleanup decisions and policy development regarding soil heavy metals, and (2) to increase public awareness of the levels of naturally occurring and anthropogenic background heavy metals in soil and sediments across the state. The publicly accessible and interactive dashboard offers a deeper understanding of background environmental conditions in relation to evolving anthropogenic contamination within a broader context.

Though freshwater harmful algal blooms have been described and studied for decades, several important dynamics remain uncertain, including the relationships among nutrient concentrations, phytoplankton growth, and cyanotoxin production. To identify when and where nutrients limit phytoplankton, cyanobacteria, and cyanotoxins, we conducted in situ bioassay studies. We added nitrogen (N), phosphorus (P), or N + P across various seasons in water collected from three locations across Utah Lake, one of the largest freshwater lakes in the western U.S. This shallow, hypereutrophic lake provides a powerful testbed for quantifying nutrient-growth-toxin interactions. We assessed a range of parameters over time, including photopigment concentrations, phytoplankton abundance (cell counts), cyanotoxins, and nutrient concentrations. Despite high background nutrient concentrations in lake water, phytoplankton abundance and composition were strongly affected by nutrient addition. Phosphorus limitation was more common in the spring, with N limitation and N + P limitation becoming more common in the fall. Nutrient additions were positively associated with cyanobacteria (Microcystis, Aphanocapsa, Dolichospermum, Merismopedia, Aphanizomenon spp.), eukaryotes (Aulacoseira, Desmodesmus spp.), and two taxonomical categories of phytoplankton (i.e., unicellular and colonial green algae). When detected, anatoxin-a was positively associated with Aphanizomenon and negatively associated with Microcystis spp. However, overall cyanotoxin concentrations were not associated with cyanobacterial cell density but varied seasonally. These findings highlight the importance of considering seasonal nutrient availability dynamics and provide insights into specific nutrient targets, species, and cyanotoxins that play a significant role in the health and management of similar eutrophic lake environments around the world.

Abstract Negative health impacts of water insecurity are often felt most in poor and rural communities and communities of color, who are more likely to be underserved by water infrastructure and disproportionately subject to socioeconomic stressors. Despite mandated efforts to allocate significant federal resources to infrastructure funding in ‘disadvantaged communities,’ communities with the most need risk systematic exclusion from access to resources, decision-making structures, and even benefits of research intended to address inequitable infrastructure services and health outcomes in their own communities. This project aims to describe groundwork and preliminary findings from community-engaged environmental research conducted within an ongoing community-based participatory research partnership in Robeson County, NC, a majority–minority county with the lowest median household income of NC’s 100 counties. Semi-structured interviews conducted with community members were analyzed to identify concerns about drinking water security (including safety, affordability, and reliability), perceptions of water quality, averting behaviors taken due to water insecurity, and ideas for improving water security. Findings suggest that there is a high level of mistrust in community water supplies, with perceptions of poor water quality driving a reliance on bottled water. Those relying on private wells expressed greater trust in their water and lower reliance on bottled water. Concerns about affordability were less prominent than those about water quality. Insufficient water reliability (low flow) was mentioned by many respondents, including those with community water service and those relying on private wells. Most supported increasing taxes to improve water security and also recommended increasing communications between water service providers and the public to improve trust. Overall, this work suggests the need for a comprehensive assessment of the quality and reliability of community water services in Robeson County, interventions to address problems identified, and much more engagement with the community about identifying and allocating funding to solve water security problems.

Marine species are expanding polewards with rising temperatures.In the Northwest Atlantic, tropical/subtropical species native to the Caribbean have been documented as spreading into temperate regions.One such species, the green porcelain crab (Petrolisthes armatus), has been migrating up the southeastern United States coastline from Florida since the 1990s.Until 2018, the species had not been detected north of Wilmington, North Carolina (NC).Here, we document the establishment of P. armatus populations along the NC central coast.During biodiversity monitoring, we detected the first record of P. armatus in 2018 in Beaufort, NC, and subsequent records of the crab were detected at multiple locations in the region over a four-year time period (2018-2022), often at relatively high abundances.Morphological and genetic evidence confirmed the identity of P. armatus in this region and distinguished it from its less abundant native congener, P. galathinus (banded porcelain crab).While cold winter temperatures have likely limited the species' ability to spread northwards in the past, rising winter temperatures in recent years may facilitate its continued expansion.It is vital that we continue monitoring the species' population demographics in its expanding range, as well as determine community-level impacts in the region.