Polycyclic Aromatic Hydrocarbons (PAHs) Occurrence and Toxicity in Camellia sinensis and Herbal Tea

This study describes a survey of polycyclic aromatic hydrocarbon (PAH) concentrations in 23 green, herbal, and black tea brands widely consumed in Nigeria by determining the levels of benzo[a]pyrene, chrysene (PAH2), benzo[a]pyrene,chrysene, benz[a]anthracene, benzo[b]fluoranthene (PAH4), benzo[a]pyrene, benz[a]anthracene, benzo[k]fluoranthene, chrysene, benzo[b]fluoranthene,dibenz[ah]anthracene, benzo[ghi]per-ylene and indeno[1,2,3-cd]pyrene (PAH8). Toxic equivalence factor and mutagenic equivalence factor were applied to evaluate the toxic equivalence and mutagenic equivalence quotients relative to benzo[a]pyrene. The concentrations of PAHs indicate that Regulation 835/2011/EC was not fulfilled by benzo[a]anthracene, B[a]A, benzo[a]pyrene, B[a]P, benzo[b]fluoranthene, B[b]F, and chrysene, CHR. The PAH4 levels ranged from 1.28 to 44.57, 4.34 to 11.20, and 0.76 to 34.82 μg/kg in green, black, and herbal tea products, respectively. On the other hand, the PAH8 concentration varied between 1.63 and 65.73, 5.02 and 68.83, and 12.43 and 24.92 μg/kg in green, herbal, and black tea samples. The PAH4 and PAH8 provide more reliable indicators for determination of PAH contamination and risk characterization in food than PAH

TRACE ELEMENTS AND PAHs SURVEY IN IMPORTED AND LOCAL Camellia sinensis COMMERCIALLY SOLD IN NIGERIA

The influx of various brands of imported and locally produced Camellia sinensis into the Nigerian market coupled with weak legislation and growing concerns about contaminants such as polycyclic aromatic hydrocarbons (PAHs) and trace metals worldwide has heightened. In this study, twenty three (23) samples of local and imported branded Camellia sinensis commercially sold in Nigeria were randomly purchased from local retail outlets. Extraction of PAHs was carried out using GC grade n-hexane. A four-stage sequential extraction procedure recommended by the Community Bureau of Reference (BCR) and Aqua regia acid cocktail were used to study the metal speciation and pseudo-total metals, respectively. Analyses of PAHs and trace metals were performed using Agilent 7890A Gas Chromatograph equipped with Flame Ionisation Detector with an autosampler and Microwave Plasma Atomic Emission Spectrometer (MP-AES), respectively. PAHs were detected in all samples with concentrations (mg/kg) ranging between 1.63 to 73.53, 4.71 to 79.61 and 12.52 to 26.89 for green, herbal and black teas, respectively. Detected PAHs were dominated by 4-5 membered ring structures and source apportionment analysis indicated biomass burning and vehicular emission as the major sources of PAHs in the investigated tea samples. The aggregate measure of carcinogenicity and mutagenicity (BaP-TEQ and BaPMEQ) values show a weak positive correlation and BaP-TEQ values were generally higher than BaP-MEQ with two herbal tea samples recording the highest values. The estimated lifetime cancer risk index due to PAHs (for children and adults in Nigeria) indicated that all samples investigated except two green tea samples exceeded the USEPA allowable limits (10- 6 to 10-4 mg/kg-day). Trace metals were present in all Camellia sinensis samples. The total concentration sequence for the tea samples were different from that of the speciation, indicating the importance the chemical forms in which the metals exist within a sample matrix, a pointer to their mobility and toxicity. Mn was most accumulated and bioavailable

Trace Metal Contamination Characteristics and Health Risks Assessment of Commelina africana L. and Psammitic Sandflats in the Niger Delta, Nigeria

The purpose of this study was to investigate and quantify trace metal concentrations in Commelina africana L. and psammitic sandflats from an intertidal coastal ecosystem in Niger Delta, Nigeria, and to evaluate their spatial distribution, degree of contamination, and source apportionment.The environmental risks associated with soil contamination were elaborately assessed using potential ecological risk index, sediment quality guidelines, and enrichment relative to background levels. The mean concentrations of Cd, Cr, Ni, Pb, and Zn in sandflat soil samples are 0.76 ± 9.0 × 10−2, 7.39 ± 8.7 × 10−1, 2.28 ± 0.35, 0.024 ± 4.0 × 10−3, and 74.51 ± 2.55mg/kg, respectively. Metal levels indicate strong variability with sampling sites. The order of trace metal concentrations in the Commelina africana L. samples is Zn > Ni > Cr > Pb > Cd.The concentrations varied with the sample locations; and the levels of Pb (0.05 to 0.08mg/kg) at all locations are found to be significantly below permissible level of 0.3mg/kg. Potential sources of metal loadings may be associated with localised or diffused anthropogenic activities.The average carcinogenic risks are below 1.0 × 10−6 threshold values, and the sandflat soils are not considered to pose significant health effects to children and adult males and females. However, the carcinogenicity and noncarcinogenicity risks ranking decrease following the order children > adult males > adult females. Comparatively, the hazard quotient and hazard index indicate that the psammitic sandflats might pose a health risk to children in future

Occurrence and distribution of microplastics-sorbed phthalic acid esters (PAEs) in coastal psammitic sediments of tropical Atlantic Ocean, Gulf of Guinea

Baseline microplastic pollution and the occurrence, spatial distribution and ecological risk of microplastic-sorbed phthalate esters (PAEs) in littoral sandflat sediments of the Gulf of Guinea were investigated. A total of 150 sediment samples were collected using a 0.5 × 0.5 × 0.2m quadrant placed along designated high, drift and current waterlines at five (5) beaches. Analysis for 6 PAEs-sorbed to microplastics (MPs) was carried out using gas chromatography – mass spectrometry (GC–MS). Microplastic particles (1–5 mm) were identified visually and FTIR spectroscopy was also used for identification. The MPs distribution was variably heterogenous with a total of 3424 particles per m2 found within the drift and high waterlines across all sites. Results indicated fragments as the dominant microplastic type compared to pellets and fibres. Polyethylene terephthalate was the major polymer type and accounted for a weighted average of 41% of the total plastics, followed by polystyrene (28%), and polypropylene (21%). TheΣ6PAEs concentration ranged from BDL to 164.09 mg/kg dw, dominated by di(2- ethylhexyl) phthalate (DEHP), dibutyl phthalate (DnBP), and dimethyl phthalate. The preliminary ecological risk assessment of PAEs in the microplastic fraction, RQmp, showed DEHP and DnBP may present medium to high biological risks to marine organisms, suggesting that future study of PAEs in total sediment versus the MP fraction might be useful to refine ecological risk assessments. Land-based anthropogenic activities are primary sources of MPs, whereas oceanographic peculiarities of the area constitute the major distribution driving forc

Data on quantification of PAHs and elemental contentindry Camellia sinensis and herbal tea

Here wepresentdataonpotentiallytoxicmetalsandpolycyclic aromatic hydrocarbons(PAHs)incommerciallysoldteabrandsin Nigeria. Thearticleprovidesdataonthesequentialextractionand the pseudo-totalconcentrationsofeightmetals(Cd,Cr,Cu,Mn,Ni, Pb, VandZn)andpolycyclicaromatichydrocarbons(PAHs)indry Camellia sinensis and herbaltea.Thethree-stepCommunityBureau of Reference(BCR)methodandaciddigestionwithaquaregia wereadoptedforsequentialandtotalmetalextractions,respec- tively.TheextractionofbrandedteasamplesforPAHsanalysishas been describedin “Concentrations, sourcesandriskcharacterisa- tion ofpolycyclicaromatichydrocarbons(PAHs)ingreen,herbal and blackteaproductsinNigeria” [1] and “PolycyclicAromatic Hydrocarbons (PAHs)OccurrenceandToxicityin C. sinensis and Herbal Tea” [2]. ElementalandPAHsanalysesofextractswere determined byMicrowavePlasmaAtomicEmissionSpectroscopy (Agilent MP-AES4100)andAgilentgaschromatograph7890A coupled with flame ionizationdetector(FID),respectivel

Trace and major elements distribution in coastal sediment cores from Lagos Lagoon,Nigeria

Heavymetalscontaminationinaquaticecosystemshasbeena majorconcern,however,noinformationisavailableaboutthe concentrations, depthdistributionsandecologicalrisksofheavy metals insedimentscoresfrommicrotidallagoonalecosystemin Lagos, Nigeria.Foursedimentcoreswerecollectedusinga 50 cm × 3.5 cmWildco®handcorer.Elementaldeterminations werecarriedoutusingtheMicrowavePlasmaAtomicEmission Spectrometry (4200MP-AES)afterextraction.Theconcentrations of heavymetalsinthesedimentcoresindicatedenhanceddegree of contaminationinfluenced byanthropogenicdischargesespe- cially industrialeffluents. Verticaldepthdistributionsindicated varieddepositionalperiodslargelycontrolledbyincreasing anthropogenicland-basedactivities.Theremarkablemetalpollu- tion ofcoresedimentsraisestheconcernpotentialsourcesof metals tothelagoonalecosystemandecologicalriskstothebiota, humans, andtheenvironment.Theresultsofelementalcon- centrations shouldbeconsideredasbaselinedataforheavymetals in sedimentsintheregion

Microplastics distribution and characterization in epipsammic sediments of tropical Atlantic Ocean, Nigeria

regional data collection and environmental dynamics are vital aspects of understanding the underlying sources and factors that influence the abundance and dispersion of the plastic particles. This paper presents a baseline report on the abundance of microplastics across three tidal waterlines (high, drift and current) of the tropical Atlantic ecosystem. Microplastics (1 – 5 mm) occurrence and distribution in epipsammic sediments of five beaches in Lagos, Nigeria (Gulf of Guinea) were assessed. The microplastics were extracted by density flotation using saturated solution of NaCl and the identification of polymer types was done by attenuated total reflectance Fourier transform infra-red spectroscopy, ATR-FTIR. Results showed significant variations in the population of MPs in the three tidal waterlines with the high and drift waterlines accounting for 58.83% and 41.16% of the total MPs, respectively while no MPs were detected in the current waterline sediment. Polyethylene, polystyrene and polypropylene were the most abundant polymers recorded. Fragments were predominantly detected and preproduction pellets formed only 5.27% of total microplastics. Polymer risk index calculations showed low to medium risk of the microplastics found and local hydrodynamic conditions such as Ocean surges and current intensity were observed to influence the distribution and dispersion of microplastics. Continuous monitoring of MPs abundance is necessary to minimize the polymers’ risk to the ecosystem

Dataset on microplastics and associated trace metals and phthalate esters in sandy beaches of tropical Atlantic ecosystems, Nigeria

This article presents data on the occurrence and distribution of phthalate esters and metals associated with microplastics (MPs) (1–5 mm) collected from four beaches in the trop- ical Atlantic ecosystems, Nigeria, Gulf of Guinea. Informa- tion on microplastics extraction by density flotation with saturated NaCl and polymer identification with attenuated total reflectance infra-red spectroscopy (ATR-FTIR) is also provided. Analysis of six phthalate esters (PAEs) (dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DnBP), benzyl butyl phthalate (BBP), di (ethyl hexyl) phtha- late (DEHP), and di n-octyl phthalate (DnOP)) associated with the microplastics by performed using Gas chromatography–mass spectroscopy (GC–MS). Metals including Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Si, Sr, Ti, Tl, V, and Zn were analysed by inductively cou- pled plasma–optical emission spectrometry (ICP–OES). The data present the separation of microplastics from sediment, extraction with cyclohexane/ethyl acetate (1:1, v/v) and 10% HNO 3 for phthalate esters and metals, respectively, and the determination of target analytes concentrations. The compo- sitional distributions of MPs and levels of carcinogenic and toxic metals and phthalate esters are presented. The dataset could be used for the evaluation of ecological risk associated with PAEs in the marine ecosystems

Polycyclic aromatic hydrocarbons in imported Sardinops sagax: Levels and health risk assessments through dietary exposure in Nigeria

Polycyclic aromatic hydrocarbons (PAHs) occurrence and assessment of dietary exposure from imported canned sardines (Sardinops sagax) commercially marketed in local stores and supermarkets in Nigeria were evaluated for the first time. PAHs determinations were performed using high performance liquid chromatography (HPLC) (Agilent 1290 model) equipped with UV-VIS diodes array detector (DAD) at l = 210 nm and 214 nm. The percentage recoveries were higher than 96%. The degree of contamination expressed as total concentration of PAH congeners ranged between 2.53 and 35.55 mg kg�1 dry weight (d. w.) at l = 210 nm, and 1.30 and 27.93 mg kg�1 (d.w.) at l = 214 nm. The carcinogenic (TEQBaP) and mutagenic toxicities (MEQBaP) of eight priority PAHs were evaluated. Benzo[a]pyrene, benzo[b] fluoranthene, benzo[k]fluoranthene and indeno[1,2,3-c,d] pyrene contributed significantly to the total carcinogenic equivalents of PAHs. The mutagenic equivalents were largely dominated by chrysene, benzo [b]fluoranthene, benzo[k]fluoranthene and benzo[a]pyrene and indeno[1,2,3-c,d]pyrene equivalence factors. The estimated lifetime average daily dose (LADD), average annual excess risk (AR), excess cancer rate (ECR), and hazard quotient risk (HQ) were evaluated for adults, children and preteens exposure related risks. The LADD, ECR, AR and HQ of PAHs for carcinogenic and non-carcinogenic risks are relatively higher in preteens than children and adults