Effects of particulate matter on daily mortality in 13 Japanese cities

BACKGROUND

In recent years, numerous reports demonstrating the relationship between an increase in the concentration of fine particulate matter (PM2.5) and daily mortality have been released in the United States and Europe. There have been few studies that clearly characterize the short-term effects of particulate matter on the mortality in Japan. We conducted data analysis to investigate the short-term effects of suspended particulate matter (SPM) on mortality in Japan.

METHODS

In this study, we used data sets from the 13 largest cities containing data on the daily mortality of residents aged 65 years or older, concentrations of air pollutants including SPM, temperature, and humidity. Risk ratios for mortality resulting from respiratory diseases, cardiovascular diseases, and all causes other than accidents, from 1990 through 1994, were summarized using a generalized additive model (GAM) and a meta-analysis of random effect model.

RESULTS

The risk ratios for an increase of 10 microg/m3 in SPM concentrations adjusted for SO2, NO2, CO, Ox, temperature, and humidity were 1.0077 for all causes of mortality, 1.0109 for respiratory diseases, and 1.0091 for cardiovascular diseases, and the lower limits of the 95% confidence intervals for the risk ratios were greater than one for all cases. With regards to the effects of time lag, risk ratios were higher for the SPM concentrations on the day when the mortality was recorded, and the preceding day.

CONCLUSIONS

These results suggest a positive relationship between SPM concentrations and daily mortality in Japan.

Sediment Trapping in Estuaries

Estuarine turbidity maxima (ETMs) are generated by a large suite of hydrodynamic and sediment dynamic processes, leading to longitudinal convergence of cross-sectionally integrated and tidally averaged transport of cohesive and noncohesive suspended particulate matter (SPM). The relative importance of these processes for SPM trapping varies substantially among estuaries depending on topography, fluvial and tidal forcing, and SPM composition. The high-frequency dynamics of ETMs are constrained by interactions with the low-frequency dynamics of the bottom pool of easily erodible sediments. Here, we use a transport decomposition to present processes that lead to convergent SPM transport, and review trapping mechanisms that lead to ETMs at the landward limit of the salt intrusion, in the freshwater zone, at topographic transitions, and by lateral processes within the cross section. We use model simulations of example estuaries to demonstrate the complex concurrence of ETM formation mechanisms. We also discuss how changes in SPM trapping mechanisms, often caused by direct human interference, can lead to the generation of hyperturbid estuaries.

Prevalence of acute respiratory infections in women and children in Western Sierra Leone due to smoke from wood and charcoal stoves

Combustion of biomass fuels (wood and charcoal) for cooking releases smoke that contains health damaging pollutants. Women and children are the most affected. Exposure to biomass smoke is associated with acute respiratory infections (ARI). This study investigated the prevalence of ARI potentially caused by smoke from wood and charcoal stoves in Western Sierra Leone, as these two fuels are the predominant fuel types used for cooking. A cross sectional study was conducted for 520 women age 15–45 years; and 520 children under 5 years of age in homes that burn wood and charcoal. A questionnaire assessing demographic, household and exposure characteristics and ARI was administered to every woman who further gave information for the child. Suspended particulate matter (SPM) was continuously monitored in fifteen homes. ARI prevalence revealed 32% and 24% for women, 64% and 44% for children in homes with wood and charcoal stoves, respectively. After adjusting for potential confounders for each group, the odds ratio of having suffered from ARI was similar for women, but remained large for children in homes with wood stoves relative to charcoal stoves (OR = 1.14, 95%CI: 0.71–1.82) and (OR = 2.03, 95%CI: 1.31–3.13), respectively. ARI prevalence was higher for children in homes with wood stoves compared with homes with charcoal stoves, but ARI prevalence for both types of fuels is higher compared with reported prevalence elsewhere. To achieve a reduction in ARI would require switching from wood and charcoal to cleaner fuels.

Short-term Influences on Suspended Particulate Matter Distribution in the Northern Gulf of Mexico: Satellite and Model Observations

Energetic meteorological events such as frontal passages and hurricanes often impact coastal regions in the northern Gulf of Mexico that influence geochemical processes in the region. Satellite remote sensing data such as winds from QuikSCAT, suspended particulate matter (SPM) concentrations derived from SeaWiFS and the outputs (sea level and surface ocean currents) of a nested navy coastal ocean model (NCOM) were combined to assess the effects of frontal passages between 23-28 March 2005 on the physical properties and the SPM characteristics in the northern Gulf of Mexico. Typical changes in wind speed and direction associated with frontal passages were observed in the latest 12.5 km wind product from QuikSCAT with easterly winds before the frontal passage undergoing systematic shifts in direction and speed and turning northerly, northwesterly during a weak and a strong front on 23 and 27 March, respectively. A quantitative comparison of model sea level results with tide gauge observations suggest better correlations near the delta than in the western part of the Gulf with elevated sea levels along the coast before the frontal passage and a large drop in sea level following the frontal passage on 27 March. Model results of surface currents suggested strong response to wind forcing with westward and onshore currents before the frontal passage reversing into eastward, southeastward direction over a six day period from 23 to 28 March 2005. Surface SPM distribution derived from SeaWiFS ocean color data for two clear days on 23 and 28 March 2005 indicated SPM plumes to be oriented with the current field with increasing concentrations in nearshore waters due to resuspension and discharge from the rivers and bays and its seaward transport following the frontal passage. The backscattering spectral slope γ, a parameter sensitive to particle size distribution also indicated lower γ values (larger particles) in nearshore waters that decreased offshore (smaller particles). The use of both satellite and model results revealed the strong interactions between physical processes and the surface particulate field in response to the frontal passage in a large river-dominated coastal margin.

Long-Term Trends of Per- and Polyfluoroalkyl Substances (PFAS) in Suspended Particular Matter from German Rivers Using the Direct Total Oxidizable Precursor (dTOP) Assay

Suspended particulate matter (SPM) from 13 riverine sampling sites of the German Environmental Specimen Bank collected between 2005 and 2019 was retrospectively investigated for per- and polyfluoroalkyl substances (PFAS). The samples were analyzed both by target analysis for 41 PFAS and by a modified total oxidizable precursor (dTOP) assay to capture also unknown precursors. Temporal trends and spatial differences were investigated by generalized linear modeling (GLM). Time trend analysis across all rivers showed decreasing trends for ∑PFCA and ∑PFSA concentrations in SPM. Trends based on target analysis (∑PFCA_target: -10.0%, ∑PFSA_target: -8.2%) were more pronounced than in the dTOP analysis (∑PFCA_dTOP: -4.2%; ∑PFSA_dTOP: -5.3%), suggesting that conventional target analysis overestimated actual decreases as precursors are not considered. ∑PFAS concentrations determined by dTOP assay were 1.3-145 times higher as compared to target analysis, indicating substantial amounts of unknown precursors in the samples. The ∑PFAS_dTOP/∑PFAS_target ratio increased at all sites between 2005 and 2019. Contamination was highest in SPM from the Elbe tributary Mulde downstream of a large industrial park. The results underscore the need to go beyond conventional target analysis and include precursors when assessing PFAS contamination in the environment. The dTOP assay is a suitable tool for this purpose.

Heavy Metals in Suspended Particulate Matter of the Zhujiang River, Southwest China: Contents, Sources, and Health Risks

To investigate the abundance, water/particle interaction behavior, sources, and potential risk of heavy metals in suspended particulate matter (SPM), a total of 22 SPM samples were collected from the Zhujiang River, Southwest China, in July 2014 (wet season). Nine heavy metal(loid)s (V, Cr, Mn, Ni, Cu, Zn, As, Cd and Pb) in SPM were detected. The results show that the selected heavy metal(loid)s in SPM appear in the following order: Mn (982.4 mg kg⁻¹) > Zn (186.8 mg kg⁻¹) > V (143.6 mg kg⁻¹) > Cr (129.1 mg kg⁻¹) > As (116.8 mg kg⁻¹) > Cu (44.1 mg kg⁻¹) > Ni (39.9 mg kg⁻¹) > Pb (38.1 mg kg⁻¹) > Cd (3.8 mg kg⁻¹). Furthermore, both the enrichment factor (EF) and geo-accumulation index (I_geo) indicate that SPM is extremely enriched in metal(loid)s of Cd and As, while SPM is slightly enriched, or not enriched, in other heavy metals. According to the toxic risk index (TRI) and hazard index (HI), arsenic accounts for the majority of the SPM toxicity (TRI = 8, 48.3 ± 10.4%) and causes the primary health risk (HI > 1), and the potential risks of V and Cr are also not negligible. By applying a correlation matrix and principal component analysis (PCA), three principal components (PC) were identified and accounted for 79.19% of the total variance. PC 1 (V, Cr, Mn, Ni, Cu, and Pb) is controlled by natural origins. PC 2 (As and Cd) is mainly contributed by anthropogenic origins in the basin. PC 3 (Zn) can be attributed to mixed sources of natural and anthropogenic origins. Moreover, all the partition coefficients (lgK_d) exceeded 2.9 (arithmetical mean value order: Mn > Pb > Cd > V ≈ Cu > Cr ≈ Ni), indicating the powerful adsorptive ability of SPM for these heavy metal(loid)s during water/particle interaction.

Toxic Effects of Inhaled Vanadium Attached to Particulate Matter: A Literature Review

Environmental pollution is a worldwide problem recognized by the World Health Organization as a major health risk factor that affects low-, middle- and high-income countries. Suspended particulate matter is among the most dangerous pollutants, since it contains toxicologically relevant agents, such as metals, including vanadium. Vanadium is a transition metal that is emitted into the atmosphere especially by the burning of fossil fuels to which dwellers are exposed. The objective of this literature review is to describe the toxic effects of vanadium and its compounds when they enter the body by inhalation, based especially on the results of a murine experimental model that elucidates the systemic effects that vanadium has on living organisms. To achieve this goal, we reviewed 85 articles on the relevance of vanadium as a component of particulate matter and its toxic effects. Throughout several years of research with the murine experimental model, we have shown that this element generates adverse effects in all the systems evaluated, because it causes immunotoxicity, hematotoxicity, neurotoxicity, nephrotoxicity and reprotoxicity, among other noxious effects. The results with this experimental model add evidence of the effects generated by environmental pollutants and increase the body of evidence that can lead us to make more intelligent environmental decisions for the welfare of all living beings.

Evidence for Assimilatory Nitrate Reduction as a Previously Overlooked Pathway of Reactive Nitrogen Transformation in Estuarine Suspended Particulate Matter

Suspended particulate matter (SPM) contributes to the loss of reactive nitrogen (Nr) in estuarine ecosystems. Although denitrification and anaerobic ammonium oxidation in SPM compensate for the current imbalance of global nitrogen (N) inputs and sinks, it is largely unclear whether other pathways for Nr transformation exist in SPM. Here, we combined stable isotope measurements with metagenomics and metatranscriptomics to verify the occurrence of dissimilatory nitrate reduction to ammonium (DNRA) in the SPM of the Pearl River Estuary (PRE). Surprisingly, the conventional functional genes of DNRA (nirBD) were abundant and highly expressed in SPM, which was inconsistent with a low potential rate. Through taxonomic and comparative genomic analyses, we demonstrated that nitrite reductase (NirBD) in conjunction with assimilatory nitrate reductase (NasA) performed assimilatory nitrate reduction (ANR) in SPM, and diverse alpha- and gamma-proteobacterial lineages were identified as key active heterotrophic ANR bacteria. Moreover, ANR was predicted to have a relative higher occurrence than denitrification and DNRA in a survey of Nr transformation pathways in SPM across the PRE spanning 65 km. Collectively, this study characterizes a previously overlooked pathway of Nr transformation mediated by heterotrophic ANR bacteria in SPM and has important implications for our understanding of N cycling in estuaries.

Higher Risks of Copper Toxicity in Turbid Waters: Quantifying the Bioavailability of Particle-Bound Metals to Set Site-Specific Water Quality Criteria

In coastal waters, particulate metals constitute a substantial fraction of the total metals; however, the prevalent water quality criteria are primarily based on dissolved metals, seemingly neglecting the contribution of particulate metals. Here we developed a method to quantify the toxicity risk of particulate metals, and proposed a way to calculate modifying factors (MFs) for setting site-specific criteria in turbid waters. Specifically, we used a side-by-side experimental design to study copper (Cu) bioaccumulation and toxicity in an estuarine clam, Potamocorbula laevis, under the exposure to "dissolved only" and "dissolved + particulate" ⁶⁵Cu. A toxicokinetic-toxicodynamic model (TK-TD) was used to quantify the processes of Cu uptake, ingestion, assimilation, egestion, and elimination, and to relate mortality risk to tissue Cu. We find that particulate Cu contributes 40-67% of the Cu bioaccumulation when the suspended particulate matter (SPM) ranges from 12 to 229 mg L^-1. The Cu-bearing SPM also increases the sensitivity of organisms to internalized Cu by decreasing the internal threshold concentration (C_IT) from 141 to 76.8 μg g^-1. MFs were derived based on the TK-TD model to consider the contribution of particulate Cu (in the studied SPM range) for increasing Cu bioaccumulation (MF = 1.3-2.2) and toxicity (MF = 2.3-3.9). Water quality criteria derived from dissolved metal exposure need to be lowered by dividing by an MF to provide adequate protection. Overall, the method we developed provides a scientifically sound framework to manage the risks of metals in turbid waters.

Development of a Cost-Effective Optical Sensor for Continuous Monitoring of Turbidity and Suspended Particulate Matter in Marine Environment

A cost-effective optical sensor for continuous in-situ monitoring of turbidity and suspended particulate matter concentration (SPM), with a production cost in raw materials less than 20 €, is presented for marine or fluvial applications. The sensor uses an infrared LED and three photodetectors with three different positions related to the light source-135º, 90º and 0º-resulting in three different types of light detection: backscattering, nephelometry and transmitted light, respectively. This design allows monitoring in any type of environment, offering a wide dynamic range and accuracy for low and high turbidity or SPM values. An ultraviolet emitter-receiver pair is also used to differentiate organic and inorganic matter through the differences in absorption at different wavelengths. The optical transducers are built in a watertight structure with a radial configuration where a printed circuit board with the electronic signal coupling is assembled. An in-lab calibration of the sensor was made to establish a relation between suspended particulate matter (SPM) or the turbidity (NTU) to the photodetectors' electrical output value in Volts. Two different sizes of seashore sand were used (180 µm and 350 µm) to evaluate the particle size susceptibility. The sensor was tested in a fluvial environment to evaluate SPM change during sediment transport caused by rain, and a real test of 22 days continuous in-situ monitoring was realized to evaluate its performance in a tidal area. The monitoring results were analysed, showing the SPM change during tidal cycles as well as the influence of the external light and biofouling problems.

Unveiling the Vertical Migration of Microplastics with Suspended Particulate Matter in the Estuarine Environment: Roles of Salinity, Particle Properties, and Hydrodynamics

The estuary is an energetic area connecting the inland, river, and ocean. The migration of microplastics (MPs) in this highly complex area is tied to the entire ecosystem. In this study, the effects of cohesive SPM (clay) and noncohesive SPM (sand) on the vertical migration of positively buoyant MPs, polyethylene (PE), and negatively buoyant MPs, polytetrafluoroethylene (PTFE), in the estuarine environment under hydrodynamic disturbances were investigated. The settling of positively buoyant MPs was more reliant on the cohesive SPM compared to the settling of negatively buoyant MPs. Moreover, MPs interacting with the SPM mixture at a clay-to-sand ratio of 1:9 settled more efficiently than those interacting with clay alone. A significant positive correlation was observed between MP settling percentage and the salinity level. MP settling percentage was significantly negatively correlated with fluid shear stress for both types of MPs, meanwhile, negatively buoyant MPs were able to resist greater hydraulic disturbances. In the low-energy mixing state, for both types of MPs, the settling percentage reached about 50% in only 10 min. The resuspension process of MPs under hydrodynamic disturbances was also uncovered. Additionally, the migration and potential sites of MPs were described in the context of prevalent environmental phenomena in estuaries.

Spatial and Temporal Distribution of Particulate Phosphorus and Their Correlation with Environmental Factors in a Shallow Eutrophic Chinese Lake (Lake Taihu)

Spatial and seasonal variations of particulate phosphorus (PP) in a large shallow, eutrophic Lake Taihu with different ecotypes (including a phytoplankton-dominated zone, lake center zone, estuary zone and macrophyte-dominated zone) were investigated. The results showed that particulate organic phosphorus (POP) was the dominant form of PP (>88.0%). The concentration of POP showed higher levels in the bloom-sensitive northwestern zone (phytoplankton-dominated zone and estuary zone) during warm seasons, phytoplankton blooms and input of exogenous particulate matter were the main sources of POP in the lake water. Based on ³¹P nuclear magnetic resonance (³¹P NMR) analysis, orthophosphate (Ortho-P) was the dominant molecular species of PP and positively correlated with soluble reactive phosphorus (SRP) (p < 0.01). This suggested that the release of Ortho-P from suspended particulate matter (SPM) was the main source of SRP in the lake water. Pyrophosphate (Pyro-P), which is regarded as a highly labile species of P compounds, represented a large fraction of PP, and its significant positive correlations with chlorophyll a (Chl a), indicated that the concentration of Pyro-P could be used as an important indicator for the degree of eutrophication of Lake Taihu. These results proved that PP in lake water was a significant factor supporting lake eutrophication and must be controlled.

Global silicate weathering flux overestimated because of sediment-water cation exchange

Rivers carry the dissolved and solid products of silicate mineral weathering, a process that removes [Formula: see text] from the atmosphere and provides a key negative climate feedback over geological timescales. Here we show that, in some river systems, a reactive exchange pool on river suspended particulate matter, bonded weakly to mineral surfaces, increases the mobile cation flux by 50%. The chemistry of both river waters and the exchange pool demonstrates exchange equilibrium, confirmed by Sr isotopes. Global silicate weathering fluxes are calculated based on riverine dissolved sodium (Na⁺) from silicate minerals. The large exchange pool supplies Na⁺ of nonsilicate origin to the dissolved load, especially in catchments with widespread marine sediments, or where rocks have equilibrated with saline basement fluids. We quantify this by comparing the riverine sediment exchange pool and river water chemistry. In some basins, cation exchange could account for the majority of sodium in the river water, significantly reducing estimates of silicate weathering. At a global scale, we demonstrate that silicate weathering fluxes are overestimated by 12 to 28%. This overestimation is greatest in regions of high erosion and high sediment loads where the negative climate feedback has a maximum sensitivity to chemical weathering reactions. In the context of other recent findings that reduce the net [Formula: see text] consumption through chemical weathering, the magnitude of the continental silicate weathering fluxes and its implications for solid Earth [Formula: see text] degassing fluxes need to be further investigated.

Assessment of persistent organic pollutants accumulation and lipid peroxidation in two reproductive stages of wild silverside (Odontesthes bonariensis)

Persistent organic pollutants (POPs) in streamwater can sometimes exceed the guidelines values reported for biota and human protection in watersheds with intensive agriculture. Oxidative stress and cytotoxicity are some of the markers of exposure to POPs in fish. Accumulation of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) as well as lipid peroxidation (LPO) was assessed in wild silverside (Odontesthes bonariensis) from maturation and pre-spawning stages sampled in a typical soybean growing area. Pollutants were quantified by gas chromatography with electron capture detection and LPO by the method of thiobarbituric acid reactive substances. Concentrations of POPs were in the following order: OCPs>PCBs>PBDEs in all organs and stages. Liver, gills and gonads had the highest OCP concentrations in both sexes and stages with a predominance of endosulfan in all samples. Matured individuals, sampled after endosulfan application period, showed higher endosulfan concentrations than pre-spawning individuals. The predominance of endosulfan sulfate could be due to direct uptake from diet and water column, as well as to the metabolism of the parent compounds in fish. The prevalence of p,p'-DDE in liver would also reflect both the direct uptake and the metabolic transformation of p,p'-DDT to p,p'-DDE by fish. The highest levels of PBDEs and PCBs were found in gills and brain of both stages of growth. The pattern BDE-47>BDE-100 in all samples corresponds to pentaBDE exposure. In the case of PCBs, penta (#101 and 110) and hexa-CB congeners (#153 and 138) dominated in the maturation stages and tri (#18) and tetra-CB (#44 and 52) in pre-spawning stages, suggesting biotransformation or preferential accumulation of heavier congeners during gonadal development. Differences in LPO levels in ovaries were associated with growth dilution and reproductive stage. Differences in LPO levels in gills were related with pesticide application periods. As a whole, endosulfan, a current-use pesticide, constituted the main pollutant found in wild silverside reflecting the intense agriculture activity in the study area. Moreover endosulfan was positively correlated with LPO.

Qualitative Dynamics of Suspended Particulate Matter in the Changjiang Estuary from Geostationary Ocean Color Images: An Empirical, Regional Modeling Approach

The suspended particulate matter (SPM) in Changjiang Estuary is characterized by a high concentration of significant diurnal dynamics. With a higher temporal resolution (eight images obtained per day), Geostationary Ocean Color Imager (GOCI) was selected as the primary remote sensor for the dynamics monitoring in this paper, instead of other satellite sensor working in polar orbit. Based on the characteristics of the field spectra measured in the estuary, an empirical model was established with the band ratio of R_rs745 divided by R_rs490 and proven effective in Suspended Particulate Matter (SPM) estimation (R² = 0.9376, RMSE = 89.32 mg/L). While, Validation results showed that the model performed better in coastal turbid waters than offshore clear waters with higher chlorophyll-a concentration, stressing the importance of partitioning SPM into its major components and doing separate analysis. The hourly observations from GOCI showed that the diurnal variation magnitudes exhibited clear regional characteristics, with a maximum in the turbidity belt near the mouth and a minimum in the offshore deeper areas. In addition, comparing the monthly averaged SPM distribution with the amount of sediment discharged into the estuary, the variation in estuarine turbidity maximum zone is more likely contributed by the sediments resuspended from the sea bed that has already accumulated in the estuarine delta.

Consistency of Suspended Particulate Matter Concentration in Turbid Water Retrieved from Sentinel-2 MSI and Landsat-8 OLI Sensors

Research on the consistency of suspended particulate matter (SPM) concentration retrieved from multisource satellite sensors can serve as long-time monitoring of water quality. To explore the influence of the atmospheric correction (AC) algorithm and the retrieval model on the consistency of the SPM concentration values, Landsat 8 Operational Land Imager (OLI) and Sentinel 2 MultiSpectral Imager (MSI) images acquired on the same day are used to compare the remote sensing reflectance (Rrs) SPM retrieval values in two high-turbidity lakes. An SPM retrieval model for Shengjin Lake is established based on field measurements and applied to OLI and MSI images: two SPM concentration products are highly consistent (R2 = 0.93, Root Mean Squared Error (RMSE) = 20.67 mg/L, Mean Absolute Percentage Error (MAPE) = 6.59%), and the desired results are also obtained in Chaohu Lake. Among the four AC algorithms (Management Unit of the North Seas Mathematical Models (MUMM), Atmospheric Correction for OLI'lite'(ACOLITE), Second Simulation of Satellite Signal in the Solar Spectrum (6S), Landsat 8 Surface Reflectance Code & Sen2cor (LaSRC & Sen2cor)), the two Rrs products, as well as the final SPM concentration products retrieved from OLI and MSI images, have the best consistency when using the MUMM algorithm in SeaWIFS Data Analyst System (SeaDAS) software. The consistency of SPM concentration values retrieved from OLI and MSI images using the same model or same form of models is significantly better than that retrieved by applying the optimal models with different forms.

Occurrence, Distribution and Ecological Risk of Bisphenol Analogues in the Surface Water from a Water Diversion Project in Nanjing, China

Due to the widespread use of bisphenol analogues (BPs) as alternatives to bisphenol A (BPA), considerable attention for health risk has been shown in aquatic ecosystems. The occurrence and distribution of six BPs were researched in a soluble phase (<10^-3 μm), colloidal phase (10^-3 μm to 1 µm), and suspended particulate matter (SPM >1 µm) in a water diversion project of Nanjing, China. Except for bisphenol Z, all BPs were detected in two or three phases, where the total concentrations of detected BPs were 161-613 ng/L, 5.19-77.2 ng/L, and 47.5-353 ng/g for the soluble phase, colloidal phase, and SPM, respectively. Among the detected compounds, BPA is still the dominant BPs in the soluble and colloidal phases, which is followed by bisphenol-S , while bisphenol-AF was the major contaminant in SPM, followed by BPA. The mean contribution proportions of colloids were 1-2 orders of magnitude higher than SPM, which suggests that colloids have a clear impact on regulating BPs' environmental behaviors. In terms of spatial distribution, the water diversion project could reduce the pollution levels of BPs, which might further affect the ecological security of the Yangtze River.

Genotoxicity and mutagenicity of suspended particulate matter of river water and waste water samples

Suspended particulate matter of samples of river water and waste water treatment plants was tested for genotoxicity and mutagenicity using the standardized umu assay and two versions of the Ames microsuspension assay. The study tries to determine the entire DNA-damaging potential of the water samples and the distribution of DNA-damaging substances among the liquid phase and solid phase. Responsiveness and sensitivity of the bioassays are compared.

Water Turbidity and Suspended Particulate Matter Concentration at Dredged Material Dumping Sites in the Southern Baltic

Dredged material dumping is an activity that causes some of the greatest changes in coastal waters. It results in the need to regularly monitor the properties of seawater related to water quality. In this study, we present the first wide-ranging attempt to correlate seawater turbidity and suspended particulate matter (SPM) concentrations within dumping sites and adjacent waters on the basis of in situ measurements. In the years 2019-2020, we examined four dumping sites, namely Darłowo, Gdynia, Gdańsk, and DCT, located in Polish coastal waters of the Baltic Sea, in the course of four measurement campaigns conducted in the spring, summer, autumn, and winter. The measurements were conducted using a turbidity sensor to determine the turbidity, in formazin turbidity units (FTU), a spectrophotometer to determine the concentrations of nutrients (total phosphorus (P-tot), phosphate phosphorus (P-PO4-3), total nitrogen (N-tot), ammonium nitrogen (N-NH4+), and nitrate nitrogen (N-NO3-)), as well as glass microfiber filters to determine the concentrations of SPM. The analysis of the relationship between the turbidity and SPM within the dumping sites in comparison to reference points showed that the dumping sites are very complex waters and that the issue must be approached locally. The highest turbidity values were registered in the spring, and they correlated linearly with the SPM concentrations (R2 = 0.69). Moreover, we performed a statistical cluster analysis to illustrate the similarities between sampling points in the four dumpsites based on nutrient concentrations. We conclude that the influence of the dumping sites on the local bio-optical and chemical properties significantly exceeds their borders and spreads to the adjacent waters. Nutrient concentrations in many cases exceeded the legal policy limits.

[Relationship Between Landscape Pattern and Spatial Variation of Heavy Metals in Aquatic Sediments in Headwaters Area of Yuqiao Reservoir]

Yuqiao Reservoir, an important adjusting reservoir in the project of diverting water from the Luanhe River to Tianjin City, is an important water resource for Tianjin City. Concentrations and spatial variation characteristics of Cd, As, Pb, Cu, Cr, and Zn from 33 sub watershed sampling sites of Yuqiao reservoir and the relationship to landscape pattern were discussed. The result showed that average concentrations of Cd, As, Cu, Cr in suspended particulate matter were higher than Chinese environmental quality standard Grade one for soils, and there were ecological risks for them because they could arrive at Yuqiao reservoir. The average concentrations of Cd, As, Pb, Cu, Cr, and Zn in surface sediments were 0.32 mg·kg^-1, 30.39 mg·kg^-1, 33.49 mg·kg^-1, 58.20 mg·kg^-1, 90.16 mg·kg^-1 and 94.80 mg·kg^-1 respectively. The average concentrations of Cd, As, Cu and the concentrations of Pb, Cr, Zn in partial samples exceeded Chinese environmental quality standard Grade one for soils. The average concentrations of Cd, Cr, Zn in surface sediments of three tributaries increased in the order of Linhe River >Shahe River >Lihe Rier, Cu decreased in the order of Linhe River < Shahe River < Lihe River, and As, Pb increased in the order of Shahe River >Linhe River >Lihe Ricer. Land use types in Yuqiao reservoir basin had some impact on the distribution of heavy metal concentrations in river surface sediments. Woodland and shrub grass land determined the natural distribution trend of heavy metals in surface sediments. Gardenland and industrial & mining land usage had impact on Cd, As, Pb, Cr distributions. Farmland and village & town land usage did not produce negative influence on heavy metal distribution.

Evaluation of Fine and Ultrafine Particles Proportion in Airborne Dust in an Industrial Area

The health impacts of suspended particulate matter (SPM) are significantly associated with size-the smaller the aerosol particles, the stronger the biological effect. Quantitative evaluation of fine and ultrafine particles (FP and UFP) is, therefore, an integral part of ongoing epidemiological studies. The mass concentrations of SPM fractions (especially PM_2.5, PM_1.0, PM_0.25) were measured in an industrial area using cascade personal samplers and a gravimetric method, and their mass ratio was determined. The results of PM_2.5, PM_1.0 were also compared with the reference measurement at stationary stations. The mean ratios PM_2.5/SPM, PM_1.0/SPM, and PM_1.0/PM_2.5 were 0.76, 0.65, and 0.86, respectively. Surprisingly, a mass dominance of UFP with an aerodynamic diameter <0.25 μm (PM_0.25) was found with mean ratios of 0.43, 0.57, 0.67 in SPM, PM_2.5 and PM_1.0. The method used showed satisfactory agreement in comparison with reference measurements. The respirable fraction may consist predominantly of UFP. Despite the measures currently being taken to improve air quality, the most biologically efficient UFP can escape and remain in the air. UFP are currently determined primarily as particle number as opposed to the mass concentration used for conventional fractions. This complicates their mutual comparison and determination of individual fraction ratios.

Prevalence of acute respiratory infections in women and children in Western Sierra Leone due to smoke from wood and charcoal stoves

Combustion of biomass fuels (wood and charcoal) for cooking releases smoke that contains health damaging pollutants. Women and children are the most affected. Exposure to biomass smoke is associated with acute respiratory infections (ARI). This study investigated the prevalence of ARI potentially caused by smoke from wood and charcoal stoves in Western Sierra Leone, as these two fuels are the predominant fuel types used for cooking. A cross sectional study was conducted for 520 women age 15-45 years; and 520 children under 5 years of age in homes that burn wood and charcoal. A questionnaire assessing demographic, household and exposure characteristics and ARI was administered to every woman who further gave information for the child. Suspended particulate matter (SPM) was continuously monitored in fifteen homes. ARI prevalence revealed 32% and 24% for women, 64% and 44% for children in homes with wood and charcoal stoves, respectively. After adjusting for potential confounders for each group, the odds ratio of having suffered from ARI was similar for women, but remained large for children in homes with wood stoves relative to charcoal stoves (OR = 1.14, 95%CI: 0.71-1.82) and (OR = 2.03, 95%CI: 1.31-3.13), respectively. ARI prevalence was higher for children in homes with wood stoves compared with homes with charcoal stoves, but ARI prevalence for both types of fuels is higher compared with reported prevalence elsewhere. To achieve a reduction in ARI would require switching from wood and charcoal to cleaner fuels.

The Legacy of the Idrija Mine Twenty-Five Years after Closing: Is Mercury in the Water Column of the Gulf of Trieste Still an Environmental Issue?

Mercury (Hg) contamination in the Gulf of Trieste (northern Adriatic Sea) due to mining activity in Idrija (Slovenia) still represents an issue of environmental concern. The Isonzo/Soča River's freshwater inputs have been identified as the main source of Hg into the Gulf, especially following periods of medium-high discharge. This research aims to evaluate the occurrence and distribution of dissolved (DHg) and particulate (PHg) Hg along the water column in the northernmost sector of the Gulf, a shallow and sheltered embayment suitable for the accumulation of fine sediments. Sediment and water samples were collected under unperturbed and perturbed environmental conditions induced by natural and anthropogenic factors. Mercury in the sediments (0.77-6.39 µg g-1) and its relationship to grain size were found to be consistent with previous research focused on the entire Gulf, testifying to the common origin of the sediment. Results showed a notable variability of DHg ( Collapse

Key Words

• mercury
• sediments
• suspended particulate matter
• water column

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MESH Headings

• Environmental Monitoring
• Geologic Sediments
• Mercury/analysis
• Mining
• Rivers
• Water
• Water Pollutants, Chemical/analysis

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Particle-size dependent of bacterial diversity associated with suspended particulate matter continuum in Lake Taihu

Suspended particulate matter (SPM) of varying particle sizes is widespread in aquatic ecosystems, providing crucial habitats for bacteria and serving as hotspots for mineralization and nutrient cycling. However, prior studies have typically treated bacteria associated with these particulates as a homogeneous group, overlooking size-related differences in diversity and composition. In this study, we separated the SPM continuum into five size-fractions (0.2, 2, 20, 200, and 500 µm) and investigated bacterial diversity, community assembly, and environmental drivers across four representative regions of Lake Taihu, China, over 1-year period. Using 16S rRNA gene sequencing, we observed particle-size-dependent variations in bacterial diversity. Alpha diversity decreased significantly with increasing particle size, while beta diversity showed a similar trend. Environmental factors influencing species richness varied by particle size, while bacteria associated with smaller particles (0.2, 2, and 20 µm) were more sensitive to environmental factors compared to those associated with larger ones (200 and 500 µm). The role of deterministic processes in community assembly increased with particle size, indicating stronger selection on larger particles. This study enhances our understanding of bacterial diversity in aquatic ecosystems and highlights the importance of particle size in bacterial community dynamics.

Connecting the dots: environmental pollution and Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental condition characterized by challenges in social communication and repetitive behavior. While the exact etiology of ASD remains elusive, researchers have increasingly turned their attention to the role of environmental factors in its development. Among these factors, environmental pollution has emerged as a potential contributor to the rising prevalence of ASD cases worldwide. This review delves into the growing body of scientific evidence suggesting a significant association between environmental pollution and the risk of ASD. It explores the environmental pollution that have been implicated, including air pollution, water contaminants, heavy metals, pesticides, and endocrine-disrupting chemicals. The detrimental impact of these pollutants on the developing brain, particularly during critical periods of gestation and early childhood has been discussed. This will provide insights into the possible mechanisms by which the various pollutants may influence the neurodevelopmental pathways underlying ASD. Additionally, the potential interplay between genetic susceptibility and environmental exposure is explored to better understand the multifactorial nature of ASD causation. Considering the alarming increase in ASD prevalence and the ubiquity of environmental pollutants, this review emphasizes the urgent need for further investigation and the adoption of comprehensive preventive measures.