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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.

Plastic products with tremendous consumption are ubiquitous in our daily lives and the annual production of plastics is drastically increasing [1]. It is now expected to reach 33 billion tonnes by 2050 [2] with plastic waste in the environment projected to reach 67.8 million metric tons by the same year [3]. The pollution of plastic cum microplastics (MPs) from degradation in the environment is currently a hot issue attracting the global attention of many scientists, governmental and non-governmental organization and the public media [3-7]. Although few studies have investigated the chemical behavior and toxicity of MPs in the natural environment, studies focusing on its toxicity in tandem with toxic chemicals to ecosystems are scarce [1,4,8]. There are many toxicology reports that MPs are harmful to ecosystems. Terrestrial organisms such as earthworms, soil collembolans, and other animals, as well as plants have been affected by MPs [1,4,9-13]. Also, aquatic organisms such fish, sandhoppers, sea turtle, crustacean and mussel have also been affected by MPs [14-15]. In addition, humans are exposed to MPs via trophic transfer or by direct ingestion, contact and inhalation and plausible effects include lung inflammation and genotoxicity may occur [1,3,16,17]. Aside from the innate toxicity of MPs, they can carry different toxic chemicals such as heavy metals and organic pollutant by adsorption process, and double the effect of such pollutants [1,8,18]. Succinctly, plastic products are made up of mixtures of polymers, fillers, and multiple additives to improve its usability. Also, there are other chemicals including unreacted monomers, starting substances and non-intentionally added substances (NIAS; impurities, side or breakdown products) that are also present in plastic. However, most of these chemicals are not covalently bound to the polymer, so they can be released at all stages of the plastics' life cycle via migration to liquids or solids or via volatilization [1]. Therefore, plastic materials are an important source of human exposure to chemicals.

Abstract. This study assessed the quality of palm oil and soil from Ihube community, Okigwe L.G.A of Imo state in October 2015. The soil samples were collected from the top soil and the palm oil were collected immediately after extraction. Palm oil and soil were analyzed using standard analytical methods and the results obtained were compared to standards. The physicochemical analysis of the soil samples showed that ranges of EC (323.33±0.57-480.33±1.53 us/cm); Moisture Content (MC) ranged from 20.9±0.80 to 40.8±0.10); %SOM (1.92±0.61-4.85±0.01) which were within the acceptable limits while CEC, iron content and lead were not significant. Palm oil samples had MC (0.32±0.09%) which was above the acceptable limit. The oil was acidic and free fatty acid (FFA) result for 10days showed even much acidic ranges from (2.15±0.01 to 6.07±0.05 mgNaOH/g) with Fe, (2.00±0.01 to 5.43±0.51 mgNaOH/g) with Pb and (1.27±0.03 to 5.04±0.03 mgNaOH/g) without contamination. This was tested using anova at p < 0.05 respectively and there was a significant difference between the results. However, the result obtained from these areas shows good quality soil for palm tree cultivation.

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