Thirteen elements including Al, Ag, As, Co, Cu, Cd, Cr, Fe, Mn, Ni, Se, Zn, and Pb were measured in 107 surface grab sediment samples and 175 segments of eight cores from Lakes Superior, Michigan, and Huron, using inductively coupled plasma mass spectrometry (ICP-MS). Concentrations in Ponar grabs vary considerably among metals and among locations, ranging from the highest median for Fe in Lake Superior (42,000 mg/kg) to the lowest median for Ag in the main Lake Huron (0.05 mg/kg). The inventory at coring sites ranged from 7 × 106 mg/m2 of Fe to 3 mg/m2 of Ag. The background concentrations were estimated from deeper core segments, and enrichment factors (EFs) were calculated with Fe or Al as the reference element. The results show that Al, Fe, Co, Cr, and Mn did not enrich, Ag, Cu, and Ni were present higher than expected from natural sources alone, while Pb, Cd, Se, Zn, and As have been enriched at most sites after European settlement in the region. EFs of most metals are higher for Lake Michigan than the other lakes. However, EF comparison among sampling sites revealed intrinsic problems of this approach for the assessment of human interference. Preliminary risk assessment, conducted by calculating risk quotients, revealed environmental risks of some metals in each lake; however, the results should be interpreted with caution because the approach used is considered to be conservative.

Ultrasonic humidifiers are commonly used in households to maintain indoor humidity and generate a large number of droplets or spray aerosols. However, there have been various health concerns associated with humidifier use, largely due to aerosols generated during operation. Here, we investigated the size distribution, chemical composition, and charged fraction of aerosol particles emitted from commercial ultrasonic humidifiers. Heavy metals in water used for humidifiers were found to be highly enriched in the ultrasonic humidifier aerosols (UHA), with the enrichment factors ranging from 102 to 107. This enrichment may pose health concerns for the building occupants, as UHA concentrations of up to 106 particles/cm3 or 3 mg/m3 were observed. Furthermore, approximately 90% of UHA were observed to be electrically charged, for the first time according to our knowledge. Based on this discovery, we proposed and tested a new method to remove UHA by using a simple electrical field. The designed electrical field in this work can efficiently remove 81.4% of UHA. Therefore, applying this electrical field could be an effective method to significantly reduce the health risks by UHA.

The concentration of various potentially toxic metals (Pb, Cd, As, Ni, Zn, and Cr) in street dust samples collected from Mehran city, Iran, was analyzed. The samples were obtained during normal traffic conditions, NTT, prior to the Arbaeen ceremony, as well as after the pilgrims\' return, which corresponds to high traffic time, HTT. Street dust samples were analyzed for HM content using ICP-OES, following acid digestion. The subsequent evaluation of the data involved the application of the geo-accumulation index, enrichment factor, and potential ecological risk index (PER) and health risk assessment. The findings demonstrate a notable increase in the levels of HMs during HTT compared to the NTT. The highest enrichment values for Pb and Cd were observed in Mehran Street dust during the HTT. The mean of PER for all sampling points increased to 138.24, indicating a moderate-potential ecological risk at this time. Based on the health risk assessment, it was found that the hazard index for all samples was below one. The incremental lifetime cancer risk was below 10-6. This indicates that the exposed population is not exposed to substantial health risks. Despite the heavy traffic caused by the Arbaeen ceremony in this area and the high enrichment of HMs, along with potential ecological risks, no significant health risks were observed for individuals exposed to street dust. However, it is important to note that the continuation of this trend, in the absence of proper traffic management, could lead to significant environmental and health problems in the future.

Per- and polyfluoroalkyl substances (PFAS) accumulate at the air-water interface of the surface microlayer (SML) on marine and freshwater bodies. In order to determine if including the SML when sampling bulk surface water leads to a high bias in measured PFAS concentrations, a pilot study and a full field study were conducted. The pilot study conducted at two sites was aimed at determining the analytical precision and small-scale (~1 m) spatial variability in concentrations of PFAS in bulk water and the SML. The full field study was performed at 11 sites, where three commonly used bulk surface water sampling methods were compared: (1) a peristaltic pump with tubing that excludes the SML, (2) a fully submerged sample bottle that excludes the SML, and (3) a partially submerged sample bottle that allows inclusion of the SML. The SML was sampled using the glass plate method. The samples were analyzed by liquid chromatography tandem mass spectrometry. The pilot study indicated that sampling variation was greater than analytical variation (although Levene\'s tests indicated that the differences were not statistically significant) and that relatively small differences in the mean concentration among sampling methods could be detected. The full investigation indicated that there was no evidence of high bias of PFAS concentrations in bulk surface water resulting from inclusion of SML using the partially submerged bottle sampling method. Unexpectedly, there was evidence that samples collected using the partially submerged bottle had slightly lower PFAS concentrations, particularly for less hydrophobic PFAS, than bulk water samples that excluded the SML. Additionally, the PFAS enrichment factor in the SML increased with increasing retention time, although the increase was not evident at all sampling sites for all PFAS. Integr Environ Assess Manag 2024;1-12. © 2024 SETAC.

Marginalized communities experience barriers that can prevent soil monitoring efforts and knowledge transfer. To address this challenge, this study compared two analytical methods: portable X-ray fluorescence spectroscopy (pXRF, less time, cost) and inductively coupled plasma mass spectrometry (ICP-MS, \"gold standard\"). Surface soil samples were collected from residential sites in Arizona, USA (N = 124) and public areas in Troy, New York, USA (N = 33). Soil preparation differed between groups to account for community practice. Statistical calculations were conducted, paired t test, Bland-Altman plot, and a two-way ANOVA indicated no significant difference for As, Ba, Ca, Cu, Mn, Pb, and Zn concentrations except for Ba in the t test. Iron, Ni, Cr, and K were statistically different for Arizona soils and V, Ni, Fe, and Al concentrations were statistically different for New York soils. Zinc was the only element with high R2 and low p value. Pollution load index (PLI), enrichment factors (EF), and geo-accumulation index (Igeo) were calculated for both methods using U.S. Geological Survey data. The PLI were > 1, indicating soil pollution in the two states. Between pXRF and ICP-MS, the Igeo and EF in Arizona had similar degree of contamination for most elements except Zn in garden and Pb in yard, respectively. For New York, the Igeo of As, Cu, and Zn differed by only one classification index between the two methods. The pXRF was reliable in determining As, Ba, Ca, Cu, Mn, Pb, and Zn in impacted communities. Therefore, the pXRF can be a cost-effective alternative to using ICP-MS techniques to screen soil samples for several environmentally relevant contaminants to protect environmental public health.

Since the transfer of microplastic across the sea-air interface was first reported in 2020, numerous studies have been conducted on its emission flux estimation. However, these studies have shown significant discrepancies in the estimated contribution of oceanic sources to global atmospheric microplastics, with evaluations ranging from predominant to negligible, varying by 4 orders of magnitude from 7.7 × 10-4 to 8.6 megatons per year, thereby creating considerable confusion in the research on the microplastic cycle. Here, we provide a perspective by applying the well-established theory of particulate transfer through the sea-air interface. The upper limit of global sea-air emission flux microplastics was calculated, aiming to constrain the controversy in the previously reported fluxes. Specifically, the flux of sub-100 μm microplastic cannot exceed 0.01 megatons per year, and for sub-0.1 μm nanoplastics, it would not exceed 3 × 10-7 megatons per year. Bridging this knowledge gap is crucial for a comprehensive understanding of the sea-air limb in the \"plastic cycle\", and facilitates the management of future microplastic pollution.

Potentially toxic metal(loid) assessment of tea and tea garden soil is a vital guarantee of tea safety and is very necessary. This study analyzed the distribution of seven potentially toxic metal(loid)s in different organs of the tea plants and soil at various depths in the Yangai tea farm of Guiyang City, Guizhou Province, China. Although soil potentially toxic metal(loid) in the study area is safe, there should be attention to the health risks of Cu, Ni, As, and Pb in the later stages of tea garden management. Soil As and Pb are primarily from anthropogenic sources, soil Zn is mainly affected by natural sources and human activities, and soil with other potentially toxic metal(loid) is predominantly from natural sources. Tea plants might be the enrichment of Zn and the exclusion or tolerance of As, Cu, Ni, and Pb. The tea plant has a strong ability for absorbing Cd and preferentially storing it in its roots, stems, and mature leaves. Although the Cd and other potentially toxic metal(loid)s content of tea in Guizhou Province is generally within the range of edible safety, with the increase of tea planting years, it is essential to take corresponding measures to prevent the potential health risks of Cd and other potentially toxic metal(loid)s in tea.

In many countries with wastewater irrigation and intensive use of fertilizers (minerals and organics), heavy metal deposition by crops is regarded as a major environmental concern. A study was conducted to determine the impact of mineral fertilizers, cow manure, poultry manure, leaf litter, and sugarcane bagasse on soil\'s trace Pb content and edible parts of vegetables. It also evaluated the risk of lead (Pb) contamination in water, soil, and food crops. Six vegetables (Daucus carota, Brassica oleracea, Pisum sativum, Solanum tuberosum, Raphanus sativus, and Spinacia oleracea) were grown in the field under twelve treatments with different nutrient and water inputs. The lead concentrations in soil, vegetables for all treatments and water samples ranged from 1.038-10.478, 0.09346-9.0639 mg/kg and 0.036-0.26448 mg/L, The concentration of lead in soil treated with wastewater in treatment (T6) and vegetable samples was significantly higher, exceeding the WHO\'s permitted limit. Mineral and organic fertilizers combined with wastewater treatment reduced lead (Pb) concentrations in vegetables compared to wastewater application without organic fertilizers. Health risk indexes for all treatments except wastewater treatment (T6) were less than one. Pb concentrations in mineral fertilizers, cow manure, poultry manure, leaf litter, and sugarcane bagasse treated were determined to pose no possible risk to consumers.

To investigate the influence of COVID-19 lockdown measures on PM2.5 and its chemical components in Shenyang, PM2.5 samples were continuously collected from January 1 to May 31, 2020. The samples were then analyzed for water-soluble inorganic ions, metal elements, organic carbon, and elemental carbon. The findings indicated a significant decrease in PM2.5 and its various chemical components during the lockdown period, compared to pre-lockdown levels (p < 0.05), suggesting a substantial improvement in air quality. Water-soluble inorganic ions (WSIIs) were identified as the primary contributors to PM2.5, accounting for 47% before the lockdown, 46% during the lockdown, and 37% after the lockdown. Ionic balance analysis revealed that PM2.5 exhibited neutral, weakly alkaline, and alkaline characteristics before, during, and after the lockdown, respectively. NH4+ was identified as the main balancing cation and was predominantly present in the form of NH4NO3 in the absence of complete neutralization of SO42- and NO3-. Moreover, the higher sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR), along with the significant increase in PM2.5/EC, suggested intense secondary transformation during the lockdown period. The elevated OC/EC ratio during the lockdown period implied higher secondary organic carbon (SOC), and the notable increase in SOC/EC ratio indicated a significant secondary transformation of total carbon. The enrichment factor (EF) results revealed that during the lockdown, 9 metal elements (As, Sn, Pb, Zn, Cu, Sb, Ag, Cd, and Se) were substantially impacted by anthropogenic emissions. Source analysis of PMF was employed to identify the sources of PM2.5 in Shenyang during the study period, and the analysis identified six factors: secondary sulfate and vehicle emissions, catering fume sources, secondary nitrate and coal combustion emissions, dust sources, biomass combustion, and industrial emissions, with secondary sulfate and vehicle emissions and catering fume sources contributing the most to PM2.5.

Coastal urban areas impact atmospheric chemistry and air quality through various sources, interactions, and processes. This study examines the mass concentrations of fine mode (PM2.5) aerosol and its major and trace components (Al, As, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mo, Mn, Na, Ni, Pb, Sb, Se, Sr, Te, Ti, Tl, V, Zn). The comprehensive field measurements were conducted in Poland between September 2019 and May 2020. Seasonal distribution and drivers of these pollutants showed considerable variability. In winter, higher concentrations were observed for Pb, Co, and As due to the higher contribution of pyrogenic emission. The Principal Component Analysis provided evidence of anthropogenic sources of trace species associated with coal combustion by industry/power plants, brake wear-related emissions, vehicle emissions, shipping activities, road-resuspended dust, and urban construction activities. These results showed that major chemical elements (Ca, Na, Fe, Mg, Al, and K) contributed to 4.07-34.0% of all components. Se, Zn, and Br contributed 1.29%, 1.25%, and 1.04%, respectively, while other tracers ranged between 0.07% and 0.95%. The diagnostic ratio of V/Ni remained stable between 0.45 and 0.46 during the cold season, then increased in spring, indicating that ship emissions were an important source of these metals during the warm season.