In the modern "omics" era, measurement of the human exposome is a critical missing link between genetic drivers and disease outcomes. High-resolution mass spectrometry (HRMS), routinely used in proteomics and metabolomics, has emerged as a leading technology to broadly profile chemical exposure agents and related biomolecules for accurate mass measurement, high sensitivity, rapid data acquisition, and increased resolution of chemical space. Non-targeted approaches are increasingly accessible, supporting a shift from conventional hypothesis-driven, quantitation-centric targeted analyses toward data-driven, hypothesis-generating chemical exposome-wide profiling. However, HRMS-based exposomics encounters unique challenges. New analytical and computational infrastructures are needed to expand the analysis coverage through streamlined, scalable, and harmonized workflows and data pipelines that permit longitudinal chemical exposome tracking, retrospective validation, and multi-omics integration for meaningful health-oriented inferences. In this article, we survey the literature on state-of-the-art HRMS-based technologies, review current analytical workflows and informatic pipelines, and provide an up-to-date reference on exposomic approaches for chemists, toxicologists, epidemiologists, care providers, and stakeholders in health sciences and medicine. We propose efforts to benchmark fit-for-purpose platforms for expanding coverage of chemical space, including gas/liquid chromatography-HRMS (GC-HRMS and LC-HRMS), and discuss opportunities, challenges, and strategies to advance the burgeoning field of the exposome.

• Keywords
• chemical space, chromatography, environmental exposures, exposome, high-resolution mass spectrometry, metabolomics, non-targeted analysis, toxicants,
• MeSH
• Exposome MeSH
• Mass Spectrometry * methods   MeSH
• Humans MeSH
• Metabolomics MeSH
• Proteomics methods   MeSH
• Environmental Exposure MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

The freely dissolved concentration (Cfree) of hydrophobic organic chemicals in sediments and soils is considered the driver behind chemical bioavailability and, ultimately, toxic effects in benthic organisms. Therefore, quantifying Cfree, although challenging, is critical when assessing risks of contamination in field and spiked sediments and soils (e.g., when judging remediation necessity or interpreting results of toxicity assays performed for chemical safety assessments). Here, we provide a state-of-the-art passive sampling protocol for determining Cfree in sediment and soil samples. It represents an international consensus procedure, developed during a recent interlaboratory comparison study. The protocol describes the selection and preconditioning of the passive sampling polymer, critical incubation system component dimensions, equilibration and equilibrium condition confirmation, quantitative sampler extraction, quality assurance/control issues and final calculations of Cfree. The full procedure requires several weeks (depending on the sampler used) because of prolonged equilibration times. However, hands-on time, excluding chemical analysis, is approximately 3 d for a set of about 15 replicated samples.

• MeSH
• Geologic Sediments analysis   MeSH
• Hydrophobic and Hydrophilic Interactions MeSH
• Soil Pollutants analysis   MeSH
• Solid Phase Microextraction methods   MeSH
• Soil chemistry   MeSH
• Environmental Pollution MeSH
• Publication type
• Journal Article MeSH
• Evaluation Study MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Names of Substances
• Soil Pollutants MeSH
• Soil MeSH

The freely dissolved concentration of persistent organic pollutants (POPs) is one of the most important parameters for risk assessment in aquatic environments, due to its proportionality to the chemical activity. Chemical activity difference represents the driving force for a spontaneous contaminant transport, such as water-aquatic biota or water-sediment. Freely dissolved concentrations in sediment pore water can be estimated from the concentrations in a partition-based passive sampler equilibrated in suspensions of contaminated sediment. Equilibration in the sediment/passive sampler system is slow, since concentrations of most POPs in the water phase, which is the main route for mass transfer, are very low. Adding methanol to sediment in suspension increases the POPs' solubility and, consequently, the permeability in the water phase. The resulting higher aqueous concentrations enhance POPs mass transfer up to three times for investigated POPs (polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorine pesticides) and shorten equilibrium attainment to less than 6 weeks. The addition of methanol to the aqueous phase up to a molar fraction of 0.2 changed the POPs equilibrium distribution ratio between sediment and passive sampler by less than a factor of two. As a result, the pore water concentrations of POPs, calculated from their amounts accumulated in a passive sampler, are affected by methanol addition not more than by the same factor.

• Keywords
• Mass transfer, Partitioning, Passive sampling, Persistent organic pollutants, Sediment,
• MeSH
• Water Pollutants, Chemical analysis   MeSH
• Hydrocarbons, Chlorinated analysis   MeSH
• Geologic Sediments analysis   MeSH
• Methanol chemistry   MeSH
• Environmental Monitoring methods   MeSH
• Pesticides analysis   MeSH
• Polychlorinated Biphenyls analysis   MeSH
• Polycyclic Aromatic Hydrocarbons analysis   MeSH
• Solubility MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Water Pollutants, Chemical MeSH
• Hydrocarbons, Chlorinated MeSH
• Methanol MeSH
• Pesticides MeSH
• Polychlorinated Biphenyls MeSH
• Polycyclic Aromatic Hydrocarbons MeSH

Near-ground air (26 substances) and surface seawater (55 substances) concentrations of persistent toxic substances (PTS) were determined in July 2012 in a coordinated and coherent way around the Aegean Sea based on passive air (10 sites in 5 areas) and water (4 sites in 2 areas) sampling. The direction of air-sea exchange was determined for 18 PTS. Identical samplers were deployed at all sites and were analysed at one laboratory. hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs) as well as dichlorodiphenyltrichloroethane (DDT) and its degradation products are evenly distributed in the air of the whole region. Air concentrations of p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and o,p'-DDT and seawater concentrations of p,p'-DDE and p,p'-DDD were elevated in Thermaikos Gulf, northwestern Aegean Sea. The polychlorinated biphenyl (PCB) congener pattern in air is identical throughout the region, while polybrominated diphenylether (PBDE)patterns are obviously dissimilar between Greece and Turkey. Various pollutants, polycyclic aromatic hydrocarbons (PAHs), PCBs, DDE, and penta- and hexachlorobenzene are found close to phase equilibrium or net-volatilisational (upward flux), similarly at a remote site (on Crete) and in the more polluted Thermaikos Gulf. The results suggest that effective passive air sampling volumes may not be representative across sites when PAHs significantly partitioning to the particulate phase are included.

• MeSH
• Water Pollutants, Chemical analysis   MeSH
• DDT analysis   MeSH
• Dichlorodiphenyl Dichloroethylene analysis   MeSH
• Halogenated Diphenyl Ethers analysis   MeSH
• Hexachlorobenzene analysis   MeSH
• Hexachlorocyclohexane analysis   MeSH
• Water Quality MeSH
• Air Pollutants analysis   MeSH
• Seawater chemistry   MeSH
• Polychlorinated Biphenyls analysis   MeSH
• Polycyclic Aromatic Hydrocarbons analysis   MeSH
• Environmental Pollution analysis   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Greece MeSH
• Turkey MeSH
• Names of Substances
• Water Pollutants, Chemical MeSH
• DDT MeSH
• Dichlorodiphenyl Dichloroethylene MeSH
• Halogenated Diphenyl Ethers MeSH
• Hexachlorobenzene MeSH
• Hexachlorocyclohexane MeSH
• Air Pollutants MeSH
• o,p'-DDT MeSH Browser
• Polychlorinated Biphenyls MeSH
• Polycyclic Aromatic Hydrocarbons MeSH