Field study on the uptake pathways and their contributions to the accumulation of organophosphate esters, phthalates, and polycyclic aromatic hydrocarbons in upland rice.

Plant uptake of organic contaminants generally occurs through either root, gas-phase foliar, or particle-phase foliar uptake. Understanding these pathways is essential for food-system practitioners to reduce human exposures, and to clean contaminated-sites with phytoremediation. Herein, we conducted a field-based experiment using an improved specific exposure chamber to elucidate the uptake pathways of organophosphate esters, phthalates, and polycyclic aromatic compounds, and quantitatively assessed their contributions to organic contaminant accumulations in field-grown rice.

Bioretention Design Modifications Increase the Simulated Capture of Hydrophobic and Hydrophilic Trace Organic Compounds.

Stormwater rapidly moves trace organic contaminants (TrOCs) from the built environment to the aquatic environment. Bioretention cells reduce loadings of some TrOCs, but they struggle with hydrophilic compounds. Herein, we assessed the potential to enhance TrOC removal via changes in bioretention system design by simulating the fate of seven high-priority stormwater TrOCs (e.

Bioretention Cells Provide a 10-Fold Reduction in 6PPD-Quinone Mass Loadings to Receiving Waters: Evidence from a Field Experiment and Modeling.

Road runoff to streams and rivers exposes aquatic organisms to complex mixtures of chemical contaminants. In particular, the tire-derived chemical 6PPD-quinone (-(1,3-dimethylbutyl)-'-phenyl--phenylenediamine-quinone) is acutely toxic to several species of salmonids, which are critical to fisheries, ecosystems, and Indigenous cultures. We therefore urgently require interventions that can reduce loadings of 6PPD-quinone to salmonid habitats.

Identifying the contributions of root and foliage gaseous/particle uptakes to indoor plants for phthalates, OPFRs and PAHs.

Understanding the uptake pathways of organic chemicals in plants can help us use plants as biosentinels for human exposure, and as remediation tools for contaminated sites. Herein, we investigated the relative contributions of root and foliar (gas and particle) uptake pathways to indoor ornamental plants for phthalates (PAEs), organophosphorus flame retardants (OPFRs), and polycyclic aromatic hydrocarbons (PAHs). We looked at different kinds of indoor ornamental plants via pot and hydroponic control experiments, comparing the levels between their leaves and indoor air gaseous and particle phases, floor dust, and window film.

Emissions and fate of organophosphate esters in outdoor urban environments.

Cities are drivers of the global economy, containing products and industries that emit many chemicals. Here, we use the Multimedia Urban Model (MUM) to estimate atmospheric emissions and fate of organophosphate esters (OPEs) from 19 global mega or major cities, finding that they collectively emitted ~81,000 kg yr of ∑OPEs in 2018. Typically, polar "mobile" compounds tend to partition to and be advected by water, while non-polar "bioaccumulative" chemicals do not.

Uptake, translocation, bioaccumulation, and bioavailability of organophosphate esters in rice paddy and maize fields.

Rice and maize are two main crops with different growth habits in Northeast China. To investigate the uptake, translocation, and accumulation of organophosphate esters (OPEs) in those two crops, we measured the OPE concentrations in their agricultural soil-crop systems during different growing seasons. OPE concentrations were higher in paddy (221 ± 62.

Stormwater Bioretention Cells Are Not an Effective Treatment for Persistent and Mobile Organic Compounds (PMOCs).

Bioretention cells are a stormwater management technology intended to reduce the quantity of water entering receiving bodies. They are also used to reduce contaminant releases, but their performance is unclear for hydrophilic persistent and mobile organic compounds (PMOCs). We developed a novel eight-compartment one-dimensional (1D) multimedia model of a bioretention cell ("Bioretention Blues") and applied it to a spike and recovery experiment conducted on a system near Toronto, Canada, involving PMOC benzotriazole and four organophosphate esters (OPEs).

Occurrence and distribution of organophosphate flame retardants in the typical soil profiles of the Tibetan Plateau, China.

The urbanization and development of Tibetan Plateau (TP) probably results in a significant contamination of organic pollutants, such as organophosphate flame retardants (OPFRs). However, there is a lack of monitoring and evaluation of their occurrence and risks in the soil of TP. We investigated the concentrations, vertical distributions, potential sources, and ecological risks of OPFRs in soil profiles from four regions of TP, China.

Trace Organic Contaminant Transfer and Transformation in Bioretention Cells: A Field Tracer Test with Benzotriazole.

Bioretention cells can effectively infiltrate stormwater runoff and partly remove conventional water contaminants. A field tracer injection experiment in a conventionally designed bioretention cell was used to investigate the fate of benzotriazole, a model trace organic contaminant, during and between runoff events. Moderate (29%) benzotriazole load reductions were measured during the 6 h long injection experiment.

Textile Washing Conveys SVOCs from Indoors to Outdoors: Application and Evaluation of a Residential Multimedia Model.

Indoor environments have elevated concentrations of numerous semivolatile organic compounds (SVOCs). Textiles provide a large surface area for accumulating SVOCs, which can be transported to outdoors through washing. A multimedia model was developed to estimate advective transport rates (fluxes) of 14 SVOCs from indoors to outdoors by textile washing, ventilation, and dust removal/disposal.

Novel Bayesian Method to Derive Final Adjusted Values of Physicochemical Properties: Application to 74 Compounds.

Accurate values of physicochemical properties are essential for screening semivolatile organic compounds for human and environmental hazard and risk. approaches for estimation are widely used, but the accuracy of these and measured values can be difficult to ascertain. Final adjusted values (FAVs) harmonize literature-reported measurements to ensure consistency and minimize uncertainty.

Ornamental houseplants as potential biosamplers for indoor pollution of organophosphorus flame retardants.

We investigated the occurrence, compositions, and partitioning behaviors of organophosphorus flame retardants (OPFRs) in indoor dust, air, and ornamental plants in Dalian, China, to evaluate the possibility of using houseplants as indoor biosamplers of OPFRs. The mean concentrations of OPFRs in the indoor air, dust, and plant samples were 14.9 ng/m, 18,000 ng/g, and 345 ng/g, respectively.

Pet hair as a potential sentinel of human exposure: Investigating partitioning and exposures from OPEs and PAHs in indoor dust, air, and pet hair from China.

We investigated the levels, compositions, and partitioning behaviors of organophosphate esters (OPEs) and polycyclic aromatic hydrocarbons (PAHs) in indoor air, dust, and pet hair from North China, as well as their potential exposures for humans and pets. The mean OPE concentrations in the indoor air (n = 19), dust (n = 26), and pet hair (n = 29) samples were 52.1 ng/m, 3510 ng/g, and 1440 ng/g; while the mean PAH concentrations were 369 ng/m, 6000 ng/g, and 22.

Evaluation of the OECD P and LRTP screening tool for estimating the long-range transport of organophosphate esters.

Scientists and decision makers need accurate, accessible and fast tools to assess and prioritize the persistence (P) and environmental long-range transport potential (LRTP) of chemicals. Here we evaluated the Organisation for Economic Co-operation and Development (OECD) P and LRTP Screening Tool ("the Tool") with respect to the P and LRTP estimates that the Tool provides for organophosphate esters (OPEs). We found that the use of default parameter values could significantly underestimate P and LRTP values of OPEs and, potentially, other Persistent Mobile Organic Compounds (PMOCs), by not accounting for episodic atmospheric transport and poleward river-based transport in the northern hemisphere.

Characteristics and risk assessment of organophosphorus flame retardants in urban road dust of Dalian, Northeast China.

We investigated the occurrence, distribution, and potential sources of 10 organophosphorus flame retardants (OPFRs) in road dust from the urban area of Dalian, China, as well as their associated human exposures and health risks. The total concentration of ΣOPFRs ranged from 300 to 7480 ng/g with a median of 1600 ng/g. Relatively high concentrations were observed mainly near prosperous business districts or dense residential areas.

Projected declines in global DHA availability for human consumption as a result of global warming.

Docosahexaenoic acid (DHA) is an essential, omega-3, long-chain polyunsaturated fatty acid that is a key component of cell membranes and plays a vital role in vertebrate brain function. The capacity to synthesize DHA is limited in mammals, despite its critical role in neurological development and health. For humans, DHA is most commonly obtained by eating fish.

Examining the Gas-Particle Partitioning of Organophosphate Esters: How Reliable Are Air Measurements?

Organophosphate esters (OPEs) in air have been found to be captured entirely on filters of typical active air samplers and thus designated as being in the particle phase. However, this particle fraction is unexpected, especially for more volatile tris(2-chloroethyl) phosphate (TCEP) and tris(chloroisopropyl) phosphate (TCIPP). We evaluated gas-particle partitioning in indoor and outdoor air for OPEs and polybrominated diphenyl ethers (PBDEs) using single-parameter models (Junge-Pankow, Harner-Bidleman) and poly-parameter linear free energy relationship (pp-LFER) models.

Organophosphate Ester Transport, Fate, and Emissions in Toronto, Canada, Estimated Using an Updated Multimedia Urban Model.

Organophosphate esters (OPEs), used as flame retardants and plasticizers, occur at relatively high concentrations in urban air and surface waters. We tested the hypothesis that some OPEs could be considered persistent and mobile organic compounds (PMOCs), using the poly parameter linear free energy relationship-modified Multimedia Urban Model (ppLFER-MUM) in Toronto, Canada, as a case study. Modeled air emissions of ∑OPEs of 3300 (190-190 000) kg yr were 10-100 times higher than emissions of polychlorinated biphenyls (∑PCBs) and polybrominated diphenyl ethers (∑PBDEs).