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Road dust is a major source of pollution in the environment, carrying different pollutants, including heavy metals and metalloids, from one location to another. This study assesses the concentrations of eight heavy metals and one metalloid (Zn, Pb, Mn, Fe, Cr, Cu, Cd, Ni, and As) in dust samples collected from sixty-eight streets of Sharjah, United Arab Emirates using ICP-OES, as well as investigates their effects on both the environment and humans. Mean concentrations of the elements in μg/g across the sites were 392 ± 46 (Zn), 68.28 ± 11.3 (Pb), 1437 ± 67 (Mn), 39,481 ± 4611 (Fe), 460 ± 31 (Cr), 150 ± 44 (Cu), 1.25 ± 0.65 (Cd), 856 ± 72 (Ni), and 0.97 ± 0.28 (As). The Cdeg and ERI calculated from the study were 54.79 and 573, respectively, suggesting varying pollution levels. The highest contributions were from Ni, Cd, Zn, Cu, Cr, and Pb, especially in areas with heavy traffic. The non-carcinogenic risk assessments were generally low for the three routes of exposure, except HQoral that was slightly higher for children. Similarly, none of the elements exhibited any carcinogenic risk except chromium. Overall, the cancer risk is considered low. In view of the limited studies from UAE in relation to the metal content of road-deposited dusts, the current study serves as novel knowledge, especially in the context of geographical areas with a higher occurrence of sandstorms and the presence of particulate matter. The study also adds to the global understanding of the contribution of street dust to environmental pollution and its implications for human health.

Bisphenol A (BPA) is an industrial chemical that is widely used in various industrial applications. It has concerns in its use as a color developer in thermal paper receipts since it is identified as an endocrine disruptor and causes hormonal disturbances. In this study, thirty thermal paper receipt samples were randomly collected from various locations in Sharjah, United Arab Emirates and analyzed using high performance liquid chromatography-mass spectrometry. Sixty percent (60%) of receipt samples showed BPA levels above the acceptable limit (200 ng/mg) set by the European Union (EU) for thermal papers. On the other hand, 40% of the samples reported very low BPA levels (< 0.02 ng/mg). However, estimated weight adjusted daily intakes (EDI) ranged between 8.22 ×10-11 and 0.000812 μg/kg bw/day for the general population, and between 7.89×10-9 and 0.0681 μg/kg bw/day for the occupationally exposed cashiers. Thus, all calculated EDIs were below the European Food Safety Authority Tolerable Daily Intake (4 μg/kg·bw/day) and the provisional Health Canada Tolerable Daily Intake (25 ug/kg bw/day) under varying paper-to-skin transfer coefficients and absorption fractions. Nevertheless, due to its health effects and recent legal restrictions by EU, the occurrence of co-exposure to dietary and non-dietary sources should be considered in the health risk assessment of Bisphenol A, mainly for people with frequent occupational exposure to thermal paper, and especially with the increased use of sanitizers. The current study is a first within the UAE context in relation to BPA in thermal paper receipts, thus its significance especially with the recent EU enforcement of BPA limits in paper receipts. The study highlights that proper policies as well as education and awareness may assist in limiting transdermal BPA exposure for the general and occupationally exposed populations.

This study investigated the presence of pharmaceuticals in the water and sediment of Buffalo and Sundays River Estuary, South Africa. Extraction for water and sediment samples was achieved with solid-phase extraction and ultrasonic extraction methods, respectively. Quantification of the target analytes was done with UPLC-QTOF-MS. The pH of surface water in all the sampling sites (8.18–10.1) were above the WHO guideline (6.5). A good correlation was observed between the concentrations of analytes with organic matter and organic carbon. Results showed that carbamazepine exhibited the highest concentration (8.75 ± 1.45 μg/kg) of all the pharmaceuticals, while trimethoprim has the highest detection frequency with the highest concentration of 1.62 ± 0.83 μg/kg in the sediment samples. Sulfamethoxazole was below the detection limit in both estuaries. Calculated risk quotients revealed that carbamazepine and trimethoprim could be of potential risk, while caffeine may pose a very low risk to the aquatic organisms investigated. Proper monitoring of the runoff entering Buffalo Estuary is required, being the point of discharge of Buffalo River to the Indian Ocean. Also, the domestic waste discharge from residences in the surroundings of Sundays Estuary should be monitored.

The occurrence and antibiogram profiles of Listeria monocytogenes in environmental waters in the Eastern Cape Province, South Africa, were investigated. Seventy-eight samples from rivers, wastewater, and irrigation water were collected at different geographical locations within the province from February to September 2019. The procedure of the International Organization for Standardization EN ISO 11290:2017 part 1 and 2 was adopted for the isolation of Lm. The counts of presumptive Lm ranged from 2.0 × 103 CFU/100 ml to 3.6 × 105 CFU/100 ml. About 39.74% of the samples were positive for Lm, and the isolates were confirmed as serotype 1/2a (78.95%) and serotype 4b (21.05%). About 68.42% of the isolates demonstrated biofilm-forming potentials. Ten virulence determinants including the plcA, inlA, and inlB were detected in all the isolates; however, inlC (85.97%), inlJ (80.70%), actA (59.65%), prfA (92.98%), plcB (89.47%), hly (80.70%), and mpl (73.68%) were less prevalent. The antibiogram profiles of confirmed Lm isolates revealed high susceptibilities (>50%) to all antibiotics ranging from 52.63% (cefotetan) to 100% (ampicillin) except for sulfamethoxazole (35.09%), erythromycin (26.32%), streptomycin (38.60%), oxytetracycline (45.61%), and amoxicillin (49.12%). Conversely, high resistance rates against sulfamethoxazole (63.16%), oxytetracycline (54.39%), and amoxicillin (50.88%) were observed. Isolates exhibited 52 resistance patterns against 22 antibiotics tested ranging from 1 to 15 antibiotics, and 82.46% showed multidrug-resistance phenotypes against the antibiotics. The antibiotic resistance index (ARI) of river water (0.18) was less than the permissible (0.2) Krumperman threshold, whereas that of irrigation and wastewater were higher than the Krumperman threshold. The multiple/antibiotic resistance index ((M)ARI) of each of the isolates ranged from 0.05–0.68. Resistance determinants (21) encoding resistance against sulphonamides, β-lactamase, phenicols, aminoglycosides, and tetracyclines were detected among the phenotypically resistant Lm isolates investigated which justifies the phenotypic resistance observed in this study. The abundance of resistance determinants in Lm recovered from environmental waters in this study suggests that the aquatic environments may serve as a channel for the dissemination of antimicrobial-resistant Lm to other niches including the food chain.

The occurrence and persistence of pharmaceuticals in the food chain, particularly edible crops, can adversely affect human and environmental health. In this study, the impacts of the absorption, translocation, accumulation, and degradation of paracetamol in different organs of the leafy vegetable crop spinach (Spinacia oleracea) were assessed under controlled laboratory conditions. Spinach plants were exposed to 50 mg/L, 100 mg/L, and 200 mg/L paracetamol in 20% Hoagland solution at the vegetative phase in a hydroponic system. Exposed plants exhibited pronounced phytotoxic effects during the eight days trial period, with highly significant reductions seen in the plants’ morphological parameters. The increasing paracetamol stress levels adversely affected the plants’ photosynthetic machinery, altering the chlorophyll fluorescence parameters (Fv/Fm and PSII), photosynthetic pigments (Chl a, Chl b and carotenoid contents), and composition of essential nutrients and elements. The LC-MS results indicated that the spinach organs receiving various paracetamol levels on day four exhibited significant uptake and translocation of the drug from roots to aerial parts, while degradation of the drug was observed after eight days. The VITEK® 2 system identified several bacterial strains (e.g., members of Burkhulderia, Sphingomonas, Pseudomonas, Staphylococcus, Stenotrophomonas and Kocuria) isolated from spinach shoots and roots. These microbes have the potential to biodegrade paracetamol and other organic micro-pollutants. Our findings provide novel insights to mitigate the risks associated with pharmaceutical pollution in the environment and explore the bioremediation potential of edible crops and their associated microbial consortium to remove these pollutants effectively.

Listeria monocytogenes (L. monocytogenes) is the etiologic agent of listeriosis which significantly affects immunocompromised individuals. The potential risk of infection attributed to L. monocytogenes in irrigation water and agricultural soil, which are key transmission pathways of microbial hazards to the human population, was evaluated using the quantitative microbial risk assessment modelling. A Monte Carlo simulation with 10,000 iterations was used to characterize the risks. High counts of L. monocytogenes in irrigation water (mean: 11.96 × 102 CFU/100 mL; range: 0.00 to 56.67 × 102 CFU/100 mL) and agricultural soil samples (mean: 19.64 × 102 CFU/g; range: 1.33 × 102 to 62.33 × 102 CFU/g) were documented. Consequently, a high annual infection risk of 5.50 × 10−2 (0.00 to 48.30 × 10−2), 54.50 × 10−2 (9.10 × 10−3 to 1.00) and 70.50 × 10−2 (3.60 × 10−2 to 1.00) was observed for adults exposed to contaminated irrigation water, adults exposed to contaminated agricultural soil and children exposed to agricultural soil, respectively. This study, therefore, documents a huge public health threat attributed to the high probability of infection in humans exposed to L. monocytogenes in irrigation water and agricultural soil in Amathole and Chris Hani District Municipalities in the Eastern Cape province of South Africa.

The concentrations, potential sources, and compositional profile of PBDEs in the surface water and sediment of Nahoon Estuary, East London, South Africa, were investigated with solid-phase extraction and ultra-sonication, respectively, followed by gas-chromatography-electron capture detection. The seasonal range of the contaminants’ concentrations in water and sediment samples in spring season were ∑PBDE 329 ± 48.3 ng/L (25.32–785 ng/L) and ∑PBDE 4.19 ± 0.35 ng/g dw (1.91–6.57 ng/g), but ∑PBDE 62.1 ± 1.50 ng/L (30.1–110 ng/L) and ∑PBDE 65.4 ± 15.9 ng/g dw (1.98–235 ng/g) in summer, respectively. NH1 (first sampling point) was the most contaminated site with PBDE in the Estuary. The potential source of pollution is attributed to the stormwater runoff from a creek emptying directly into the Estuary. This study’s dominant PBDE congener is BDE-17, ranging from below detection limit to 247 ng/L and 0.14–32.1 ng/g in water and sediment samples, respectively. Most detected at all the sites were BDE-17, 47, 66, and 100. Most BDE-153 and 183 are found in sediment in agreement with the fact that higher brominated congeners of PBDE adsorb to solid materials. There was no correlation between the congeners and organic carbon and organic matter. However, the human health risk assessment conducted revealed that the PBDE concentration detected in the estuary poses a low eco-toxicological risk. Nevertheless, constant monitoring should be ensured to see that the river remains safe for the users, as it serves as a form of recreation to the public and a catchment to some neighbourhoods.

Pharmaceuticals and personal care products are an integral part of societal health yet their presence in various environmental compartments, including treated wastewaters, has sparked concerns towards possible human and ecological health effects. The current study aims to characterize human health risks posed by ten pharmaceuticals quantified in wastewater treatment plant effluents where water is reused mainly for landscape irrigation. Receptors were identified as children playing in green areas, adult landscape workers, and adult users of athletic and golf courses irrigated by treated wastewater. The human health risk assessment model exhibited safe exposure (RQ

Roadside dust resulting from industrialization of society has an adverse effect on the environment and human health. However, despite the global research progress in this field, to date, no bibliometric report on the subject has been documented. Hence, bibliometric mapping is important to assess the quality and quantity of the global research activities on road dust. Data were retrieved from the Web of Science Core Collection and Scopus, while RStudio software was used for data analysis. A total of 1186 publications were retrieved from these databases, and progressive growth in the subject over the last 10 years was observed, considering the positive correlation (y = 0.0024 × 3 − 0.1454 × 2 + 2.6061 × −8.5371; R2 = 0.961) obtained for these indices. China had the highest publications, and environmental science-related journals dominated publications on road dust. The findings suggest that other regions of the world, such as the Middle East and Africa, need to channel their research efforts toward this field, considering the shortage of publications on the subject from these regions. Therefore, this study shows that assessing research activity on road dust is important for planning impactful research directions and setting protective and adaptive policies related to the field.

The present work describes the optimization and validation of a highly selective and sensitive analytical method using solid phase extraction and liquid chromatography tandem mass spectrometry (SPE LC-MS/MS) for the determination of some frequently prescribed pharmaceuticals in urban wastewater received and treated by Sharjah sewage treatment plant (STP). The extraction efficiency of different SPE cartridges was tested and the simultaneous extraction of pharmaceuticals was successfully accomplished using hydrophilic-lipophilic-balanced reversed phase Waters® Oasis HLB cartridge (200 mg/ 6 mL) at pH 3. The analytes were separated on an Aquity BEH C18 column (1.7 µm, 2.1 mm × 150 mm) using gradient elution and mass spectrometric analysis were performed in multiple reactions monitoring (MRM) selecting two precursor ions to produce ion transition for each pharmaceutical using positive electrospray ionization (+ESI) mode. The correlation coefficient values in the linear calibration plot for each target compound exceeded 0.99 and the recovery percentages of the investigated pharmaceuticals were more than 84%. Limit of detection (LOD) varied between 0.1⁻1.5 ng/L and limit of quantification (LOQ) was 0.3⁻5 ng/L for all analytes. The precision of the method was calculated as the relative standard deviation (RSD%) of replicate measurements and was found to be in the ranges of 2.2% to 7.7% and 2.2% to 8.6% for inter and intra-day analysis, respectively. All of the obtained validation parameters satisfied the requirements and guidelines of analytical method validation.