Priority polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) were investigated in heavy-traffic roadside soils in Ibadan, Nigeria to assess the level of contamination and human health risk. PAHs and HMs were analyzed using gas chromatography-mass spectrometry (GC-MS) and atomic absorption spectroscopy. The concentrations of ∑11PAHs were 263.2 ± 20.9 to 380.0 ± 23.8 µg kg–1, with a dominance of the higher molecular PAHs, and the soils can be classified as weakly contaminated. The most abundant PAH was fluoranthene. Also, five carcinogenic PAH were identified in the study. PAH diagnostic ratios suggested mixed pyrogenic and petrogenic sources. Roadside soil concentrations (mg kg−1) of Cd, Ni and Pb were 1.3 ± 1.2–5.3 ± 7.4, 15.0 ± 7.3–24.5 ± 4.8 and 41.6 ± 13.7–56.8 ± 8.3, respectively. Pollution indices revealed roadside soils were highly contaminated with Cd and Pb according to contamination factor and geoaccumulation index. Cd presented a considerable to high ecological risk. Health risk assessment for children and adults revealed soil ingestion was the main exposure pathway to metals. The hazard quotient (HQ) and health index (HI) were within the safe level (<1.0), although, HI values were higher for children. The cancer risk of exposure to Pb in roadside soils (1.18 E–06 to 1.61 E–06) was within safe limit (1.0 E–04 to 1.0 E–06). This study provides the basis for the reduction of anthropogenic emissions of PAHs and HMs.

This study collected ambient air particulate concentrations and dry depositions at Taichung Shuinan Economic and Trade Park (T.S.E.T.P.) sampling site. The global dry depositions model was applied with known particle sizes, pollutant concentrations in ambient air pollutants dry deposition estimates at T.S.E.T.P. site in Central Taiwan. Statistical analysis of the correlated relationships among ambient air particulate concentration, dry depositions, and dry deposition velocities with respect to the meteorological conditions at T.S.E.T.P. site was also conducted. The results indicated that the average dry deposition fluxes were 377.81 µg/m2*min, the average TSP concentrations were 41.53 µg/m3, and the average dry depositions velocity (Vd ) was 15.26 cm/s. In addition, 40 μm was selected as the best ambient air particulate size for the calculated dry deposition velocities to estimate ambient air dry deposition fluxes using the Global model at this T.S.E.T.P. sampling site. Moreover, ambient air particulates concentrations were higher in the fall season than that of the summer season. Sincepollutants parcels were not easily diffused during the fall season because of the low mixed atmospheric layer in this season. Therefore, atmospheric particulates concentrations were higher from the northern side than that of southern side in this study. Furthermore, wind speed V.S. particulate dry depositions and wind V.S. dry depositions velocity displayed a moderate correlated relationship, while particulate dry depositions V.S. particulate dry depositions velocity presented the highest correlated relationship at this T.S.E.T.P. sampling site. However, particulate dry depositions and dry depositions velocity presented significant differences. Finally, particulate dry depositions and dry depositions velocity were not only highly correlation related but also displayed significant differences at the T.S.E.T.P. sampling site.

This study evaluates human health, pollution, and radiological risk assessment of potentially toxic metals (PTMs) (Pb, Cd, Cr, Ni, and Zn), radioisotopes (238U, 232Th, and 40K) and its associated radiological indices from dumpsite soils in Ogun State, Nigeria, using a calibrated atomic absorption spectrophotometer (AAS) and highly shielded γ-ray spectrometry using NaI(TI) detector. Fourier transform infrared spectrometer (FTIR) complemented by X-ray diffraction (XRD) techniques were used to evaluate the mineralogical composition of the soils. Multivariate statistical analysis was used to apportion the source of PTMs and the radioisotopes. The mean concentration of Pb, Cd, Cr, Ni, and Zn obtained were 22.35, 17.95, 20.83, 19.02, and 75.88 mg kg−1, respectively. The activity concentrations of 238U, 232Th, and 40K ranged from 49.71 ± 16.3 − 314.15 ± 55.2, BDL − 87.54 ± 7.38, and BDL − 3721.3 ± 231.6 Bqkg−1, respectively. The values obtained were above the global average value in most of the samples. According to the four-pollution and ecological risk assessment model, the dumpsite soils are strongly to low polluted and enriched with toxic metals in the order Zn > Cr > Pb > Ni > Cd. The estimated carcinogenic risk of the three carcinogenic PTMs for children and adults were higher than the acceptable limit (1 × 10−6). The results of the PCA and HCA results are consistent with the correlation coefficient analysis which showed that mixed natural, anthropogenic and lithogenic sources mainly from aggregation of lead-containing materials in the waste on the dumpsite, vehicular emission and industrial discharges are the main sources of Pb, Ni, and Cd in the three studied dumpsites. Thus, dumpsite soil poses great threat to health, increased pollution and enhances the radiological risk to the general population via human multiple exposure routes.

The effect of waste dumps on groundwater quality on perched aquifers in Nsukka and environs was investigated by applying multivariate statistical analyses using Statgraphics Centurion XVII, ArcGIS 10.2.2 and Surfer 10 software on hydrochemical parameters from soil (0 cm and 15 cm depth) and groundwater media. Factor analysis, correlation, principal component analysis and cluster analysis reflect biodegradable domestic solid contaminants, automobile contaminants and construction or building contaminants. The significant or positive correlation between parameters was taken at value equal to or greater than 0.5. Chromium showed positive or significant correlation with copper (0.98), cadmium (0.91), nitrate (0.87) and potassium (0.82) indicating that they are from the same source. Zinc showed positive correlation with manganese (0.89) and pH (0.70) showing similar source. The first cluster showed chromium, copper, cadmium, nitrate, potassium and iron which could be attributed to market and domestic biodegradable wastes. The second cluster showed parameter association for lead, EC and mercury which could be attributed to automobile wastes. The third cluster showed zinc, manganese and pH which could be attributed to construction and building wastes. This showed that the third cluster is the major contributor to the soil pH. Based on the Normality Tests (Shapiro-Wilk significance test) to determine P-Value of the analyzed parameters, in the study area; there was no significant spatial variation (@p > 0.05) in the values of parameters such as chromium, iron, pH in the impact zone and the control area. Conversely, the other parameters were statistically significant. For the groundwater analysis, the dendrogram extracted three clusters highlighting the parameter associations according to their possible sources of occurrence. The first cluster showed potassium, sodium, DOI, manganese, and bicarbonate, which could be attributed to construction and building wastes. The second cluster showed parameter association for sulfate, nitrate, calcium and chloride; which could be domestic biodegradable solid waste. The third cluster showed pH, EC, TDS, Cu+, Pb2+, Hg+, Fe2+, Cr2+ and Cd2+ which could be attributed to automobile wastes.

The objective of this study was to investigate the variations and correlations of the air pollutants during Covid-19 pandemic lock-down period for an industrialized city of Turkey. With this aim, air quality data measured at four different stations in the period March–June 2020 were used. Results of the study demonstrated that lock-down period caused significant decreases in pollution levels in urban, industrialized, and rural sites. In the city center (Station 2), reduction determined for PM10 and NO x levels were 32.95% and 58.26%, respectively whereas in the industrialized site (Station 3) decrease ratios of these pollutants were 17.11% and 47.87%, respectively. Obtained reduction ratios may indicate that industrial and traffic activities have more significant contributions to NO x emissions in the region. A strong positive correlation between CO and NO x (r = 0.87) may also be evidence for traffic-related pollution in the city center while positively correlated NO x and SO2 levels indicate the importance of point sources for Stations 1 and 3. Coherent with the literature, O3 emissions showed increasing tendency both in moderately industrialized (Station 1) and rural sites (Station 4). When average concentrations of the pollutants were compared for May 2019 and May 2020 periods, the most significant variation was noted for the industrialized region with 50.07% reduction in NO x values.

The radiometric mapping of the terrestrial ionizing radiation to evaluate the possible radiological health risk to residents of Agbor and Asaba metropolis have been conducted, using a digilert nuclear radiation monitor meter and geographical positioning system (GPS). The two monitored cities and environs were delineated into five zones. Measured zones mean outdoor background ionizing radiation (BIR) levels in Asaba ranged from 0.012 ± 0.003 mRh−1 (1.01 ± 0.27 mSvy−1 to 0.023 ± 0.009 mRh−1 (1.96 ± 0.82 mSvy−1) with total mean value of 0.018 ± 0.006 (1.52 ± 0.49 mSvy−1). In Agbor, zones mean outdoor BIR levels ranged from 0.012 ± 0.004 mRh−1 (1.01 ± 0.35 mSvy−1 to 0.019 ± 0.004 mRh−1 (1.58 ± 0.37 mSvy−1) with total mean value of 0.016 ± 0.004 (1.38 ± 0.38 mSvy−1). The mean outdoor absorbed dose rate for Asaba and Agbor are 158.34 ± 50.44 and 141.52 ± 29.58 respectively. The mean annual effective dose equivalent (AEDE) for the two cities are 0.19 ± 0.05 and 0.16 ± 0.05 mSvy−1, respectively, while the mean excess lifetime cancer risk (ELCR) are (0.69 ± 0.21 and 0.64 ± 0.17) × 10−3 mSvy−1, respectively. The estimated effective dosage to organs received shows that testes have the highest dose of 0.10 mSvy−1, with liver receiving the lowest dose of 0.06 mSvy−1. The study revealed that of the 100 sampling locations, 76 sampling sites outdoor radiation levels (76%) exceeded the World ambient standard levels of 0.013 mRh−1(1.0 mSvy−1). The overall results obtained shows elevation of BIR levels and all the estimated risk parameters except ELCR and effective doses to organs, above recommended limit for the public. However, these values obtained will not constitute any immediate radiological health risk to the residents of the study areas.

This study was conducted to estimate natural radionuclide contents in 24 fish samples collected from rivers of South Africa’s oil-rich and non-oil-rich areas. Also, the radiological analysis was performed to assess the effect of radiation on the population that consumed these fish. A high-resolution Hyper Pure Germanium (HPGe) detector was used to conduct the gamma-ray measurements. The mean activity concentrations for the selected fish samples from the examined areas for 238U, 232Th, and 40K ranged from 8.60 ± 2.97, 4.26 ± 1.18, and 105.66 ± 47.77 for the Bree; 8.06 ± 3.64, 4.84 ± 2.00, and 126.88 ± 47.30 for Klein-Brak; 8.30 ± 3.64, 3.48 ± 1.44, and 90.42 ± 29.35 for Bakens; and 6.48 ± 2.05, 5.26 ± 1.79, and 78.38 ± 20.55 for uMngeni rivers. The annual effective ingestion dose ranged from 0.050 (Argyrosomus japonicus) to 0.100 (Lichia amia) for the Bree; 0.033 (Pomadasys commersonnii) to 0.118 (Pomatomus saltatrix) for Klein-Brak; 0.034 (Enteromius pallidus) to 0.090 (Anguilla marmorata) for Bakens; and 0.046 (A. marmorata) to 0.082 (Hypseleotris cyprinoides) for uMngeni river, respectively. Also, the estimated values for the annual equivalent dose of gonads, bone marrow, and bone surface cells due to ingestion of fish samples ranged from 58.77 to 127.27 for Bree; 42.14 to 125.94 for Klein-Brak; 39.34 to 84.97 for Bakens; and 54.54 to 71.97 for uMngeni rivers (control), respectively. The activity concentrations and radiological dose estimates reported for the studied areas were within the values recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation. Hence, the result of the activity concentrations in the selected fish samples at the time of this study does not pose a radiological risk. The results could also be used as reference data for radioactivity pollution in the study area.

The widespread detection of per- and polyfluoroalkyl substances (PFAS) throughout the world and the ongoing proliferation of environmental regulations has prompted the need for a forensic approach for the source attribution of PFAS. Current LC-MS/MS standard methods are sensitive and robust, but only characterize a small fraction of the total potential PFAS signature. Other, more powerful analytical tools such as HRMS exist, and have been used to characterize some of the unknown or “non-target” fraction of PFAS, but these methods are expensive and not widely available. This paper presents a tiered approach to PFAS forensics based on standard methods and/or other relatively inexpensive methodologies. The approach outlined herein is broken into three tiers, including (1) a screening method to assess the general characteristics of the bulk PFAS signature; (2) a standard method to sensitively measure PFAS compounds of regulatory interest; and (3) a method for resolving the isomer patterns of select PFAS compounds. The combination of these readily accessible methods is illustrated herein with different source materials, including aqueous film forming foam (AFFF) concentrate samples and food contact materials (FCMs). The tiered PFAS forensic approach bridges the gap between ground breaking academic methods and production laboratory throughput for the purpose of identifying valuable forensic information available in PFAS source materials.

In the assessment of atmospheric deposition using lichen transplants, coping with uncertainty is mandatory in cases of environmental forensics, when understanding whether an area is polluted or not, or tracing a given pollution source is of paramount importance. In this article, we have suggested a method based on the calculation of exposed-to-control ratios of element concentrations and on the quantification of the overall uncertainty associated with such calculation, which proved to be very robust and can be applied in most cases using a minimum of three replicates. The method allowed the selection of significantly accumulated elements i.e. those polluting the site under study, as well as the evaluation of whether a site is significantly polluted or not. We recommend the use of this evaluation method in biomonitoring studies based on transplanted samples.

The entry of illegally discharged waste into the sewage system can cause serious damage to sewage pipes and harm the public domain. Besides industrial and communal sources, discharges from clandestine laboratories are of special forensic interest. Aim of this study is to investigate the possibility to detect clandestine discharges of possibly hazardous waste directly at the point of discharge. Tests were performed at a facility where real wastewater was pumped in a controlled way through an open sewage pipe above ground. Chloride, ammonia, pH and conductivity electrodes were investigated for their ability to detect discharges of different types of waste. Waste samples were diluted up to 50 times in a static wastewater environment and pH, conductivity and chloride electrodes were able to distinguish all waste dilutions from blank wastewater. These three electrodes were then used for dynamic tests by placing them inside flowing sewage water and discharging different types of liquid waste ten meters upstream of them. Parameters of the waste discharges like volume, time interval and speed of discharge were varied and the responses of the electrodes were collected. The dynamic tests showed that these three electrodes were able to pick up different waste discharges in a real wastewater environment. It was found that a high sampling rate of the sensors would be required to connect a certain discharge to a specific household connection. These findings highlight the possibility to locate illegal discharges, coming from a variety of sources, using the waste discharge itself.