Microplastics (of size < 5 mm) pollution in our environment is of current concern by researchers, public media and non-governmental organizations. Implications by their presence in aquatic and soil ...ecosystems have been well studied and documented, but less attention has been paid on airborne microplastics (MPs). Studies concerning airborne microplastics started from 2016 and only a few (
n
= 13) have been published to date. Although, studies may increase in the following years, since air is very important for human survival. Microplastics have been observed in atmospheric fallouts in indoor and outdoor environments using a sampling or vacuum pump, rain sampler, and/or particulate fallout collector. Identification and quantification have been carried out by visual, spectroscopic, and spectrometric techniques. Factors such as meteorological, climatic, and anthropogenic influence the distribution and movement of airborne MP. Human exposure may be through inhalation, dermal, and open meal during fallout, with their potential biopersistence and translocation. Ingestion may cause localized inflammation and cancer due to responses by the immune cells, especially in individuals with compromised metabolism and poor clearance mechanisms. Ecological risks involve possible contamination of the ecosystem through a dynamic relationship of MPs in soil, water, and air forming a MP contamination cycle. The present review aimed at providing a comprehensive overview of current knowledge or information regarding microplastics in air, identifying gap in knowledge, and giving suggestions for future research.
•Different types of PET MPs were optimized for removing CIP from aqueous solution using Response Surface Methodology and Machine Learning algorithms.•ANN could predict the adsorption process better ...than Decision Tree (DT), Random Forest (RF), and Support Vector Machine (SVM).•PET MPs have a high potential for removing CIP through adsorption and can be used in treatment systems for cleaner and more sustainable discharge into the environment.
Emerging pollutants such as ciprofloxacin (CIP) and microplastics (MPs) has been found in environment, as a result of their widespread usage. In this study, the use of different polyethylene terephthalate microplastics (PET MPs) such as pristine (Pr-PET), acid modified (Mod-PET) and thermal-oxidatively aged (Ag-PET) were optimized for their removal efficiencies for CIP (5 to 50 mg/L) from aqueous solution using Response Surface Methodology with Central Composite Design (4 factors − 2 levels) and Machine Learning (ML) algorithm such as Artificial Neural Networks (ANN), Decision Tree (DT), Random Forest (RF), and Support Vector Machine (SVM). Through the use of the desirability function, the optimal conditionswere determined and amaximum removal efficiency of93.95%, 94.36%, and 96.29% for Pr-PET, Mod-PET, and Ag-PET MPs, respectively. The Dumwald-Wagner intraparticle model and the Dual-Exponential Model (DEM) were used to describe the adsorption process. The Dumwald-Wagner modelwas able to describe the adsorption process before equilibrium was reached at 12 hrs. The DEM model divided the adsorption process into two stages, a rapid, initial stage and a slower, secondary stage.These results suggest that the use of PET MPs for removing CIP through adsorption is a viable option and can be implemented in treatment systems.
Current problem facing researchers globally is microplastics as well as toxic chemical pollution of the ecosystem. Microplastics carry toxic chemicals in the ecosystem serving as a vector for ...transport. In this study, a review of the literature has been conducted with the following objectives: (1) to summarize the concentrations of toxic chemicals such heavy metals and hydrophobic organic contaminants sorped on microplastics; (2) to evaluate their spatial distribution regarding adsorbed contaminant; (3) to discuss plausible mechanism by which microplastics adsorp or desorp toxic chemicals in the environment; (4) to discuss implications of their occurrence in air, water and soil media; and (5) to discuss the impact of ingested microplastics to human health. Microplastics are ubiquitous environmental contaminant. Concentrations of sorped toxic chemical varied by location which represents a local problem; industrialized areas (especially areas experiencing crude oil-related activities or have history of crude oil pollution) have higher concentrations than less industrialized areas. Ingestion of microplastics has been demonstrated in a range of marine and soil organisms as well as edible plants, thus possibly contaminating the base of the food web. Potential health effect to human is by particle localization, chemical toxicity and microbial toxins. We conclude by highlighting the gap in knowledge and suggesting key future areas of research for scientists and policymakers.
Anthropogenic activities causing a transformation of the natural nitrogen and phosphorus cycle are considered as one of the most fundamental environmental issues. In this study, nitrate and phosphate ...concentrations in waterbodies such as Abadaba river, Agulu lake, Njaba river, Oguta Lake, and Nike Lake located in Southeast, Nigeria was determined in both dry and wet season by spectrophotometric technique and modeled for pollution and health risks assessment. Result revealed that nitrate ranged from 13.163±2.30 mg/L at Nike to 36.173±7.22 mg/L Oguta lake in dry season while in the wet season it ranged from 17.402±3.459 mg/L at Abadaba to 26.748±6.536 mg/L at Njaba river. Phosphate ranged from 2.144±0.513 mg/L at Nike to 9.741±3.207 mg/L at Oguta in dry season while from 36.330±7.420 mg/L at Abadaba to 40.204±6.024 mg/L at Oguta. Comparing results with World Health Organization (WHO) allowed limits, it revealed that nitrate was low while phosphate was only low in the dry season at Abadaba, Agulu and Oguta lake. The waterbodies showed low variations (< 20 %) with positive linear relationships (R2 ≥ 0.3) for both nitrate and phosphate in both dry and wet season. Furthermore, except at Abadaba and Agulu in the dry/wet season and Njaba and Oguta in wet season, which showed no significant differences (p > 0.05) between them, all other showed significant difference (p < 0.05) for nitrate and phosphate concentrations. In terms of season, only at Njaba (for phosphate only) showed no significant differences (p > 0.05), all others waterbodies showed significant differences (p < 0.05) in nitrate and phosphate concentration in both seasons. The nitrate to phosphate ratio was very low especially in the wet season due to the high input of phosphate. The nutrient pollution index showed moderate to very high pollution while the waterbodies will pose very high non-carcinogenic health risks to users via the oral pathway. Overall, the waterbodies are at risk of eutrophication and efforts should be put in place to reduce anthropogenic activities around the area and thus input of nutrients in these water bodies.
Molecular docking, molecular dynamics modelling, and fractional factorial design methodologies were used in the current work to examine the harmful effects of ten microplastic (MPs) such as ...polystyrene (PS), polyvinylchloride (PVC), polyurethane (PU), polymethyl methacrylate (PMMA), polyamide (PA), polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polychloropene (PCP) and polycarbonate (PC) on the aquatic organism (zebrafish). The toxicity was evaluated based on the docking of the MPs on cytochrome P450 (CYP P450) protein crystals. The binding affinities (ΔG) followed the order, PC (−6.9 kcal/mol) > PET (−6.1 kcal/mol) > PP (−5.8 kcal/mol) > PA (−5.6 kcal/mol) > PS (−5.1 kcal/mol) > PU (−4.1 kcal/mol) > PMMA (−3.9 kcal/mol) > PCP (−3.3 kcal/mol) > PVC (−2.4 kcal/mol) > PE (−2.1 kcal/mol). The primary driving factors for the binding of the MPs and the protein were hydrophobic force, and hydrogen bonding based on the molecular dynamics analysis and surrounding amino acid residues. Furthermore, a 210−5 fractional factorial design method was estimated to identify the main effect and second-order effects of MPs in a composite contamination system on binding affinity/energy to CYP450 receptor protein of zebrafish, combined with a fixed effects model. The findings showed that different MPs combinations had varying impacts on aquatic toxicity; as a consequence, the best combination of MPs with the lowest aquatic toxicity effect could be excluded. The factorial designs showed that the PU-PS and PP-PA combination and single PCP, has the most significant main effect on CYP450 receptor protein of zebrafish which translates to an optimum toxicity level of −4.61 kcal/mol. The investigation offers a theoretical foundation for identifying the hazardous impacts of MPs on aquatic life.
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•Polycarbonate have high binding affinity on CYP P450 protein crystals.•The hydrophobic force, and hydrogen bonding are primary driving factors for the binding of the MPs and the protein.•A 210−5 fractional factorial design method was estimated to identify the main effect.•PU-PS and PP-PA combination and single PCP, has the most significant main effect on zebrafish.
Microplastic research in Nigeria is progressing slowly. Within 2019-2020, only10research papers have been published on microplastic in Nigeria. Microplastics have been detected in lagoons and rivers ...water systems. This paper reviews the progress in microplastics research in Nigeria, providing information analytical methods and also giving consideration for quality control and assurance (QA/QC) measures. This paper further discusses the distribution of microplastics in surface water, sediment and marine organisms as well as recent progress in risk assessments.Finally, this paper provides suggestions for future studies to provide baseline information for better research and risk assessment of microplastics in the Nigerian environment such as focusing on air, drinking water, plants and other consumables.These will surely help us to understand the distribution and how much exposure inhabitants are to microplastic pollution and may necessitate the need to mitigate plastic pollution in Nigeria.
•PET showed the most toxic material for the sex toys.•BBP is most toxic phthalates leached from the sex toys.•PDMS, a silicone-based polymer indicates a safer profile among those tested.•Sex toys ...have the potential to induce immunotoxicity from usage,.
The widespread use of sex toys has sparked concerns about potential health risks associated with the leaching of micro/nanoplastics (M/NPs) and phthalates. In this in silico toxicity analysis, we investigated the immunotoxicity potential of compounds mechanically produced from sex toys. The research focuses on understanding their interactions with critical human cytochrome P450 enzymes (CYP34A and CYP2D6), which are central to drug metabolism and immune function. Four types of M/NPs (polyethylene terephthalate - PET, polyvinyl chloride - PVC, polydimethylsiloxane - PDMS, polyisoprene) and eight phthalates (Diethyl phthalate - DEP, Bis(4-methyl-2-pentyl) phthalate, Bis(2-methoxyethyl) phthalate, Benzyl butyl phthalate - BBP, Dibutyl Phthalate - DBP, Diethylhexyl phthalate - DEHP, Dinonyl phthalate - DNP, Di-n-octyl phthalate - DnOP) from sex toys were analyzed. Molecular dynamics and docking simulations were conducted to assess the binding affinity of these compounds to the enzymes. PET exhibited the highest toxicity, with a binding affinity of -8.3 kcal/mol and -8.9 kcal/mol for CYP3A4 and CYP2D6, respectively, surpassing control values (-7.8 kcal/mol and -6.3 kcal/mol). BBP showed considerable toxicity, binding strongly to CYP3A4 (-7.8 kcal/mol) and CYP2D6 (-9.1 kcal/mol). PDMS and DEP were the lowest toxic compounds in both groups. Molecular interactions revealed hydrogen bonds, pi interactions, and unfavorable donor-donor effects between compounds and specific amino acid residues within the enzymes. While these in silico findings provide insights, they underscore the need for comprehensive chemical analyses and absorption studies to validate health risks. This research emphasizes the necessity of evaluating the toxicity of M/NPs and phthalates from sex toys, promoting further investigations to protect individuals' health during product use.
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•Response surface methodology (RSM) was used to optimize phenol adsorption by PET MPs.•The response (removal rate) with a maximum of 93.72 %, 92.78 % and 95.80 % was recorded for Pr-PET MPs, Mod-PET ...MPs and Ag-PET MPs.•PET MPs uptake of phenol ions occurred by both multilayer and pore filling processes.
Optimization modeling and the interpretation of the adsorptive uptake of phenol from aqueous solution using pristine (Pr), modified (Mod-) and aged (Ag-) polyethylene terephthalate microplastics (PET MPs) as adsorbents at optimum conditions have been investigated. The surface morphology and functional groups of the MPs were evaluated using SEM and FTIR-ATR systems, while the surface area of the MPs was estimated using the Brunauer-Emmett Teller (BET) model. Experimentally determined optimization and Response Surface Methodology (RSM) were used to simulate and interpret the adsorption of phenol onto PET MPs, to determine the effects of four adsorption factors (contact-time, initial concentration, pH, and temperature) on the response (removal efficiency) using central composite design (CCD). The results showed that optimum operating conditions for the PET MPs adsorption of phenol from aqueous solution corresponds to contact-time of 77 minutes, 50 mg/L initial concentration, pH of 6, and temperature of 298 K respectively. The maximum removal efficiency of phenol ions under this operating condition was found to be 93.72%, 92.78% and 95.80% for Pr-PET MPs, Mod-PET MPs and Ag-PETMPs respectively. To understand the nature of the PET MPs sorption process, Redlich−Peterson (R-P), Elovich and Dubinin-Radushkevich (D-R) isotherms were employed. The results proved that, D-R model best fitted the PET MPs sorption process at 0.7214 ≤ R2 ≤ 0.9043. Elovich model confirmed the performances of the PET MPs uptake of phenol ions occurred by physical and exothermic processes. Their adsorption capacities followed Pr-PET MPs (0.226 mg/g) > Ag-PET MPs (0.216 mg/g) > Mod-PET MPs (0.126 mg/g) respectively.
As a cheap source of high-quality protein, healthy fats and essential nutrients, dried fish is a common item in the daily diet of the Bangladesh populace. In this study, ten types of widely consumed ...dried fish (H. neherius, T. lepturu, P.chinensis, P. affinis, A. mola, P. microdon, I. megaloptera, C. dussumieri, L. calcarifer, and G. chapra) were analyzed for Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Hg, Pb, Ni and As by using an Energy Dispersive X-ray Fluorescence (EDXRF) technique. The concentration of the studied metals was found in the order Fe > Zn > Hg > Cu > Se > Cr > Mn > Co > Rb > Pb, while As and Ni were below the limit of detection. All fish species showed moderate to high pollution, where the species H. Neherius and P. Chinensis are the most and least polluted ones, respectively. The probable source of contamination is the leaching from the drying pans into the fish samples, atmospheric deposition, anthropogenic contamination, etc. of the water body where these fish were harvested. The calculated hazard index for the general population was below the maximum limiting value (i.e., < 1) except for Hg to children. The carcinogenic risk showed values lower than the acceptable limit for cancer risks (10
to 10
). Periodic monitoring of trace metals in the aquatic organisms along with fish is recommended to avoid any unexpected health hazards caused by the toxic heavy metals via fish consumption.
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