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Annual deaths caused by exposure to outdoor-indoor particulate matter air pollution are a problem currently faced by the World Health Organization. This study assessed outdoor and indoor exposure to PM10 particulate matter in the city of Riohacha (Colombia) from March 17 to April 17, 2018, in three representative sites of the urban area. A low-volume gravimetric sampler, more specifically a MiniVol Portable Air Sampler operating at 5 L/min, was used at three sampling stations. Elemental analysis was performed on a microwave plasma atomic emission spectrometer (MP-AES). In total, 14 inorganic elements (Zn, Fe, Cd, V, Ca, Ni, Cu, As, Co, Pb, K, Mn, Mg, and Na) were quantified in the PM10 mass. The indoor and outdoor concentrations of PM10 ranged from 3.81 to 19.07 μg/m3 and from 17.86 to 51.35 μg/m3, respectively. The indoor/outdoor ratio of PM10 concentrations ranged from 0.213 ± 0.01 at the station with the lowest levels of PM10 to 0.360 ± 0.02 at the station with the highest levels of PM10. Chemical elements with the highest levels in PM10 were crustal elements (Ca, Na, K, Fe, Mg, As, and Co), and those with the lowest levels in PM10 were anthropogenic tracers emitted from transportation (Cd, V, Cu, Mn, Ni, Pb, and Zn). Source contributions were estimated by principal component analysis. Three factors were detected inside and three outside the stations. The emissions from motor vehicles, resuspension of road dust and marine aerosol were the major sources contributing to overall PM10 mass in Riohacha City.

Background: Despite increasing evidence that particulate air pollution has adverse effects on human semen quality, few studies examine the impact of air pollution on clinically relevant thresholds used to diagnose male fertility problems. Furthermore, exposure is often assessed using average air pollution levels in a geographic area rather than individualized estimates. Finally, physiologically-informed exposure windows are inconsistent. Objectives: We sought to test the hypothesis that airborne particulate exposures during early-phase spermatogenesis will have a differential impact on spermatogenic formation compared to late-phase exposures, using an individualized model of exposure to particulate matter ≤ 2.5 µm and ≤ 10 µm (PM2.5 and PM10, respectively). Methods: From an original cohort of 183 couples, we conducted a retrospective analysis of 130 healthy males seeking to become parents, using spermatogenesis-relevant exposure windows of 77–34 days and 37–0 days prior to semen collection to encompass sperm development stages of mitosis/meiosis and spermiogenesis, respectively. Individualized residential exposure to PM2.5 and PM10 was estimated by selecting multiple air pollution sensors within the same geographic air basin as participants and employing inverse distance weighting to calculate mean daily exposure levels. We used multiple logistic regression to assess the association between pollution, temperature, and dichotomized World Health Organization semen parameters. Results: During the early phase of spermatogenesis, air pollution exposure is associated with 1.52 (95% CI: 1.04–2.32) times greater odds of

Lead (Pb) in drinking water has re-emerged as a modern public health threat which can vary widely in space and in time (i.e., between homes, within homes and even at the same tap over time). Spatial and temporal water Pb variability in buildings is the combined result of water chemistry, hydraulics, Pb plumbing materials and water use patterns. This makes it challenging to obtain meaningful water Pb data with which to estimate potential exposure to residents. The objectives of this review paper are to describe the root causes of intrinsic Pb variability in drinking water, which in turn impacts the numerous existing water sampling protocols for Pb. Such knowledge can assist the public health community, the drinking water industry, and other interested groups to interpret/compare existing drinking water Pb data, develop appropriate sampling protocols to answer specific questions relating to Pb in water, and understand potential exposure to Pb-contaminated water. Overall, review of the literature indicated that drinking water sampling for Pb assessment can serve many purposes. Regulatory compliance sampling protocols are useful in assessing community-wide compliance with a water Pb regulatory standard by typically employing practical single samples. More complex multi-sample protocols are useful for comprehensive Pb plumbing source determination (e.g., Pb service line, Pb brass faucet, Pb solder joint) or Pb form identification (i.e., particulate Pb release) in buildings. Exposure assessment sampling can employ cumulative water samples that directly capture an approximate average water Pb concentration over a prolonged period of normal household water use. Exposure assessment may conceivably also employ frequent random single samples, but this approach warrants further investigation. Each protocol has a specific use answering one or more questions relevant to Pb in water. In order to establish statistical correlations to blood Pb measurements or to predict blood Pb levels from existing datasets, the suitability of available drinking water Pb datasets in representing water Pb exposure needs to be understood and the uncertainties need to be characterized.

Specific structures of oat and barley β(1,3)(1,4)-glucans induced different in vitro immunomodulatory effects in bone marrow derived dendritic cells (BMDC) from TLR2/4 knock out mice. All barley β-glucan fractions induced larger amounts of cytokines in BMDCs than their oat equivalents. The particulate fractions of both glucans induced high amounts of cytokines, especially after sample homogenisation. The small particulate barley β-glucans induced more cytokines than the equivalent oat fraction, hence there are more features influencing the immunomodulatory properties of β-glucans than only the particle size. The soluble glucan fraction and heated suspension induced only low amounts of cytokines, but were different for the two β-glucans, indicating that molecular specificity matters for immunomodulation. Immunomodulatory activity is influenced by the insolubility of β-glucans, to which characteristics as particle size, granule conformation and particulate homogeneity are related. Consequently, sample preparation influences the immunomodulatory activity of β-glucans.

Water lead measurements by two field analyzers, relying on anodic stripping voltammetry (ASV) and fluorescence spectroscopy, were compared to reference laboratory measurements by inductively coupled plasma mass spectrometry (ICP-MS) in progressively complex datasets (phases A, B, C), to assess field analyzer performance. Under controlled laboratory quantitative tests of dissolved lead within the field analysis range and optimal temperature range, lead recoveries by ASV ranged within 85-106 % of reference laboratory values (corresponding linear model: y = 0.96x, r 2  = 0.99), compared to lower lead recoveries of 60-80 % by fluorescence (y = 0.69x, r 2  = 0.99) in phase A. Field analyzer performance deteriorated in three opportunistic laboratory datasets compiled for phase B that contained dissolved lead (ASV: y = 0.80x, r 2  = 0.98; no fluorescence data). Further lead underestimations were observed in five field datasets compiled for phase C, some of which contained known particulate lead (ASV: y = 0.54x, r 2  = 0.76; fluorescence: y = 0.06x, r 2  = 0.38). Deteriorating performance between phases was presumably due to the increasingly complex water matrices and lead particulates present in some phase C subsets (phase A < phase B < phase C). Phase C field samples had lead concentrations that were out-of-range, including a 5 % and 31 % false negative rate by ASV and by fluorescence, respectively. The range of results relevant to the diverse nature of compiled datasets, suggests that unless ideal conditions are known to be present (i.e., the lead content of water is dissolved within the field analysis range and optimal water temperature range), these field lead analyses might only be used as a water screening tool. Given the unknown conditions in many field settings, combined with the lead concentration underestimations including the false negative rates reported herein for field datasets, caution is encouraged when employing ASV and particularly fluorescence field analysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

A healthy indigenous intestinal microbiome is indispensable for intra- and extra-intestinal human health. Since well-established factors such as diet and antibiotic use only explain 16 % of the inter-individual variation in gut microbiome composition, recent studies have focused on the association between ambient particulate air pollution and the intestinal microbiome. We systematically summarize and discuss all evidence concerning the effect of particulate air pollution on intestinal bacterial diversity indices, specific bacterial taxa, and potential underlying intestinal mechanisms. To this end, all possibly relevant publications published between February 1982 and January 2023 were screened, and eventually, 48 articles were included. The vast majority (n = 35) of these studies were animal studies. The exposure periods investigated in the human epidemiological studies (n = 12) ranged from infancy through elderly. This systematic review found that intestinal microbiome diversity indices were generally negatively associated with particulate air pollution in epidemiological studies, with an increase in taxa belonging to Bacteroidetes (two studies), Deferribacterota (one study), and Proteobacteria (four studies), a decrease in taxa belonging to Verrucomicrobiota (one study), and no consensus for taxa belonging to Actinobacteria (six studies) and Firmicutes (seven studies). There was no unequivocal effect of ambient particulate air pollution exposure on bacterial indices and taxa in animal studies. Only one study in humans examined a possible underlying mechanism; yet, the included in vitro and animal studies depicted higher gut damage, inflammation, oxidative stress, and permeability in exposed versus unexposed animals. Overall, the population-based studies showed a dose-related continuum of short- and long-term ambient particulate air pollution exposure on lower gut diversity and shifts in taxa over the entire life course., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Glyoxal (Gly) and methylglyoxal (Mgly) are key precursors globally for secondary organic aerosol (SOA) formation. These two species were often thought to be formed in the atmosphere via photochemical oxidation of organics from biogenic and anthropogenic origins, although few studies have shown their direct emissions. In this study, we report direct emissions of particulate Gly and Mgly from different residential fuels typically used in north China. The emission ratios (ERs) and emission factors (EFs) of particulate Gly and Mgly for biomass burning were approximate 5-fold and 7-fold higher than those for coal combustion, respectively. The large variances in emissions of Gly and Mgly could be attributed to the different combustion processes, which influenced by the fuel types and combustion conditions. The averaged ERs and EFs of particulate Gly and Mgly were about one order of magnitude lower than their gaseous counterparts due to the low Henry's law constant, which was also consistent with the low particle-to-gas ratio of Gly (0.04) and Mgly (0.02). Our results suggest that the direct emissions of Gly and Mgly from emission sources should be considered when estimating the formation of SOA from Gly and Mgly., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Radionuclide depth distribution in bottom sediments in deep-water zones of dam reservoirs, where no sediment mixing occurs, can be used to reconstruct time changes in particulate activity concentrations of radionuclides strongly bound to bottom sediments. This approach was used to analyze the 137 Cs concentration profile in a bottom sediment core collected from Ogaki dam reservoir on the Ukedo River in the Fukushima Dai-ichi nuclear power plant contaminated zone in October 2019. The derived 137 Cs particulate concentrations provided a basis for estimating the dissolved concentration and its temporal trend in the Ukedo River, using the mean value of the apparent 137 Cs distribution coefficient. The reconstructed particulate and dissolved 137 Cs concentrations and their temporal trends are consistent with monitoring data. The annual mean particulate and dissolved 137 Cs wash-off ratios were also calculated for the period of eight years after the accident. Interestingly, the particulate 137 Cs wash-off ratios for the Ukedo River at Ogaki dam were found to be similar to those for the Pripyat River at Chernobyl in the same time period after the accident, while the dissolved 137 Cs wash-off ratios in the Ukedo River were an order of magnitude lower than the corresponding values in the Pripyat River. Both the particulate and dissolved 137 Cs wash-off ratios in the Ukedo River declined faster during the first eight years after the FDNPP accident than predicted by the diffusional model, most likely, due to greater natural attenuation and, to some extent, remediation measures implemented on the catchments in Fukushima., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

The Pearl River Estuary (PRE), the largest estuary in Southern China, regulates the fluxes of riverine trace metals into the South China Sea. However, the geochemical behavior of trace metals in this estuary is still ambiguous. In this study, we investigated the dynamics of trace metals in different phases (i.e., particulate, colloidal and truly dissolved) in the PRE in both wet and dry seasons characteristic of the region. Transformations of trace metals between particulate (>0.45 μm), colloidal (1 kDa to 0.45 μm) and truly dissolved (<1 kDa) phases were observed during the estuarine mixing. Colloidal metals (except for Pb) showed non-conservative 'removal' behavior in the low-salinity zone (S < 10‰), suggesting the coagulation of colloidal metals and subsequent deposition to bed sediments being an important sink of dissolved trace metals. By contrast, truly dissolved metals exhibited a mid-salinity maximum distribution (i.e., Mn, Ni, Cu and Cd) or little variation along the salinity gradient (i.e., Fe). The increase of truly dissolved metal concentration was accompanied by the decrease of particulate metal concentration, indicating that the desorption of suspended particles was an important source of dissolved Mn and Cd in the PRE. Metal released from the suspended particles increased in the dry season due to the high suspended particulate matter concentration. Dissolved Mn concentration in the bottom water in wet season was higher than that in dry season, implying that benthic Mn input increased as the bottom water became hypoxic. Abnormally high concentrations of particulate and dissolved Pb were observed at the lower PRE, implying the presence of a potential point source pollution. A flux model predicted that total dissolved Fe, Ni, Cu and Zn underwent net removal while dissolved Mn and Cd had net inputs during the estuarine mixing. This study raveled contrasting geochemical behaviors of trace metals with different size phases and the different sources and sinks of dissolved metals in the PRE., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Despite increasing evidence that particulate air pollution has adverse effects on human semen quality, few studies examine the impact of air pollution on clinically relevant thresholds used to diagnose male fertility problems. Furthermore, exposure is often assessed using average air pollution levels in a geographic area rather than individualized estimates. Finally, physiologically-informed exposure windows are inconsistent., Objectives: We sought to test the hypothesis that airborne particulate exposures during early-phase spermatogenesis will have a differential impact on spermatogenic formation compared to late-phase exposures, using an individualized model of exposure to particulate matter ≤ 2.5 µm and ≤ 10 µm (PM 2.5 and PM 10 , respectively)., Methods: From an original cohort of 183 couples, we conducted a retrospective analysis of 130 healthy males seeking to become parents, using spermatogenesis-relevant exposure windows of 77-34 days and 37-0 days prior to semen collection to encompass sperm development stages of mitosis/meiosis and spermiogenesis, respectively. Individualized residential exposure to PM 2.5 and PM 10 was estimated by selecting multiple air pollution sensors within the same geographic air basin as participants and employing inverse distance weighting to calculate mean daily exposure levels. We used multiple logistic regression to assess the association between pollution, temperature, and dichotomized World Health Organization semen parameters., Results: During the early phase of spermatogenesis, air pollution exposure is associated with 1.52 (95% CI: 1.04-2.32) times greater odds of < 30% normal heads per 1-unit increase in IQR for PM 2.5 . In the late phase of spermatogenesis, air pollution exposure is associated with 0.35 (95% CI: 0.10-0.74) times greater odds of semen concentration < 15 million/mL per 1-unit increase in IQR for PM 2.5 , and 0.28 (95% CI: 0.07-0.72) for PM 10 ., Conclusion: Particulate exposure has a differential and more deleterious impact on sperm during early-phase spermatogenesis than late-phase., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

The effect of sludge retention time (SRT) on the production of organic nitrogen (ON) fractions (particulate, colloidal and soluble) and the biodegradability of produced soluble ON in an activated sludge process was investigated. Synthetic wastewater with no ON was fed to the four laboratory-scale reactors operated at SRTs of 2, 5, 10 and 20 d, respectively. Effluent ON from each reactor was fractionated into particulate, colloidal, and soluble ON (pON, cON, and sON). The effluent total ON contained 5.7 to 11.9 mg/L pON, 3.6 to 3.8 mg/L cON, and 2.3 to 4.6 mg/L sON. cON fraction can be larger than sON fraction in the secondary effluent. Therefore, besides focusing on sON, water resource recovery facilities aiming to meet stricter effluent TN limits should also identify appropriate technologies to target cON. More than 50% of effluent sON was biodegradable under SRTs of 2, 5, and 10 d but the biodegradability decreased to 31% at 20-d SRT. Large fractions of non-biodegradable sON (69%) at SRT of 20-d could be contributed by extracellular polymeric substances and soluble microbial products, specifically biomass associated products due to endogenous respiration. Thus, sON generated at long SRTs may take longer to decompose in receiving waters., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The current changes in vehicle movement due to 'lockdown' conditions (imposed in cities worldwide in response to the COVID-19 epidemic) provide opportunities to quantify the local impact of 'controlled interventions' on air quality and establish baseline pollution concentrations in cities. Here, we present a case study from Auckland, New Zealand, an isolated Southern Hemisphere city, which is largely unaffected by long-range pollution transport or industrial sources of air pollution. In this city, traffic flows reduced by 60-80% as a result of a government-led initiative to contain the virus by limiting all transport to only essential services. In this paper, ambient pollutant concentrations of NO 2 , O 3 , BC, PM 2.5 , and PM 10 are compared between the lockdown period and comparable periods in the historical air pollution record, while taking into account changes in the local meteorology. We show that this 'natural experiment' in source emission reductions had significant but non-linear impacts on air quality. While emission inventories and receptor modelling approaches confirm the dominance of traffic sources for NO x (86%), and BC (72%) across the city, observations suggest a consequent reduction in NO 2 of only 34-57% and a reduction in BC of 55-75%. The observed reductions in PM 2.5 (still likely to be dominated by traffic emissions), and PM 10 (dominated by sea salt, traffic emissions to a lesser extent, and affected by seasonality) were found to be significantly less (8-17% for PM 2.5 and 7-20% for PM 10 ). The impact of this unplanned controlled intervention shows the importance of establishing accurate, local-scale emission inventories, and the potential of the local atmospheric chemistry and meteorology in limiting their accuracy., Competing Interests: Declaration of competing interest No known competing interests., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The intent of this article is to provide guidance and recommendations to cell therapy product sponsors (including developers and manufacturers) and their suppliers in the cell therapy industry regarding particulate source, testing, monitoring and methods for control. This information is intended to help all parties characterize the processes that generate particulates, understand product impact and provide recommendations to control particulates generated during manufacturing of cell therapy products., (Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Besides dissolution, particle dispersion and mobilization can substantially contribute to element transfer from soils to waters. The dispersibility of the fine particulate and the associated potential losses of P and As from Bangladesh soils of the Ganges and Meghna floodplains have been evaluated with a simple dispersion test. The dispersible fraction was greater for the coarse-textured soils from the Meghna floodplain and increased with particle charge density. Particulate phosphorus (PP) and As (PAs) were the dominant forms in the dispersion, dissolved P and As being scarce to negligible. The PP and PAs were related to the amount of dispersed particulate, oxalate-extractable iron and, respectively, to the water-extractable P or phosphate-extractable As. Although reductive dissolution is reported as the main mechanism of As mobilization during prolonged monsoon flooding, the transfer in particulate form could potentially represent a major pathway for P and As transfer from soils to waters in oxic environments after sudden, extreme events. Since the frequency of extreme rainfall and floods is increasing because of the climate changes, and the intensified land cultivation is enhancing soil disturbance, larger contributions of particulate runoff to element migration from soils to waters could be expected in the future., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Many harmful cyanobacterial genera have strains that can produce potent toxins and other biologically active compounds that present a risk to the health of humans and other animals that consume or contact contaminated water. Cylindrospermopsins (CYNs) are produced by several species of cyanobacteria including Cylindrospermopsis raciborskii (Woloszynska) Seenayya and Subba Raju. Previous studies have used filtration methods to separate between the particulate and dissolved CYNs pools. Filtration may lyse cells and thus overestimate the dissolved CYNs pool. Here we employed a novel passive sampling technique to measure the proportion of dissolved CYNs in two Australian strains of C. raciborskii over the growth cycle while minimizing potential overestimation of the dissolved CYNs pool. We simultaneously compared the ratios of the two major CYNs produced by Australian strains of C. raciborskii: cylindrospermopsin (CYN) and deoxy-CYN in the particulate and dissolved pools. CYNs stayed within the cells during log phase but accumulated in the water column during stationary and senescent phases. The proportion of deoxy-CYN to CYN differed between strains but increased in both as cells aged. We conclude that while active release or leaking of CYNs from actively growing cells does occur, CYNs in the water column were primarily a result of cell lysis during stationary phase or due to other environmental stressors. The production of CYN and deoxy-CYN were a constitutive process and both the concentration of, ratio between, and release of CYN and deoxy-CYN were strain dependent. Future studies must account for the genetic diversity of CYN producers when investigating the production of CYNs in natural systems., (Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.)

Background: Biologic-reactivity to implant-debris is the primary determinant of long-term clinical performance. The following reviews: 1) the physical aspects of spinal-implant debris and 2) the local and systemic biologic responses to implant debris., Methods: Methods included are: 1) gravimetric wear analysis; 2) SEM and LALLS; 3) metal-ion analysis; 4) ELISA, toxicity testing, patch testing; and 5) metal-lymphocyte transformation testing (metal-LTT)., Results: Wear and corrosion of spine-implants produce particles and ions. Particles (0.01-1000 μm) are generally submicron ( <1 µm). Wear rates of metal-on-polymer and metal-on-metal disc arthroplasties are approximately 2-20 and 1 mm(3)/yr, respectively. Metal-on-metal total disc replacement components have significant increases in circulating metal (less than 10-fold that of controls at 4 ppb-Co and 3 ppb-Cr or ng/mL). Debris reactivity is local and systemic. Local inflammation is caused primarily by ingestion of debris by local macrophages, which produce pro-inflammatory cytokines TNFα, IL-1β, IL-6, and PGE2. Systemic responses associated with implant-debris have been limited to hypersensitivity reactions. Elevated amounts of in the liver, spleen, etc of patients with failed TJA have not been associated with remote toxicological or carcinogenic pathology to date. Implant debris are differentially bioreactive. Greater numbers are pro-inflammatory; the smaller-sized debris are more bioreactive by virtue of their greater numbers (dose) for a given amount of implant mass loss (one 100-μm-diameter particle is equivalent in mass to 1 million 1-μm-diameter particles). Elongated particles are pro-inflammatory (ie, aspect ratio of greater than 3). Metal particles are more proinflammatory than polymers, ceteris paribus., Conclusion: Spinal arthroplasty designs have been in use for more than 20 years internationally; therefore, concerns about neuropathology, toxicity, and carcinogenicity are mitigated. Debris-induced inflammation still depends on the individual and the type of debris. The consequence of debris-induced inflammation is continued; vigilance by physicians is recommended monitoring of spinal implants using physical exams and testing of metal content and bioreactivity, as is planning for the likelihood of revision in younger individuals.