Original research article
Trace amount determination of monocyclic and polycyclic aromatic hydrocarbons in fruits: Extraction and analytical approaches

https://doi.org/10.1016/j.jfca.2017.12.034Get rights and content

Highlights

  • Use of HS-SPME and UAE/SPE followed by GC–MS for aromatic hydrocarbons determination.

  • Development and validation for quantification of BTEX and 12 PAHs in fruits.

  • Methods showed good validation results.

  • Methods provided reliable estimation of aromatic hydrocarbons content at μg/kg level.

  • Statistical results showed adaptability of methods to various fruits.

Abstract

Two reliable and complementary approaches have been established for the determination of volatile and semi-volatile aromatic hydrocarbons at μg/kg level in fruits. Headspace solid-phase microextraction was used for extraction of monocyclic and light polycyclic aromatic hydrocarbons (MW ≤ 178 g/mol). Method based on ultrasound-assisted extraction followed by solid-phase extraction allowed extraction of heavy polycyclic aromatic hydrocarbons (MW ≥ 202 g/mol). Extraction techniques coupled with analysis by gas chromatography-mass spectrometry were successfully applied to 18 aromatic compounds in different fruit matrices (apple, pear, plum, and grape). Applicability of methods to these several fruits had been statistically verified through ANOVA test, by comparison of linear regression responses (slopes) of calibrations curves. Developed methods showed good linearity (r2 = 0.919–0.999) within a range of concentrations from 0 to 10 μg/kg wet weight and acceptable values were obtained for repeatability (RSD = 1–22%) and intermediate precision (RSD 3–30%). Limits of detection and quantification did not exceed 0.2 and 0.6 μg/kg, respectively, except for fluorene in grape (0.5 and 1.8 μg/kg, respectively). Extraction and analytical methodologies implemented in the present study allow sensitive determination of trace levels of monocyclic and polycyclic aromatic hydrocarbons in fruit.

Introduction

Aromatic hydrocarbons, which are hydrophobic organic pollutants containing one (or more) benzene ring(s), are ubiquitous. The most commonly investigated compounds are the 16 polycyclic aromatic hydrocarbons (PAHs) from the US-EPA list of priority pollutants. Benzene, toluene, and ethylbenzene, from the group of monocyclic aromatic hydrocarbons (BTEX: benzene, toluene, ethylbenzene, and xylenes), are also considered as priority pollutants (US-EPA priority pollutant list, 2014).

Benzo[a]pyrene (BaP) and benzene have been classified by the International Agency for Research on Cancer (IARC) as carcinogenic compounds. Moreover, some PAHs (BaP, dibenz[a,h]anthracene, benz[a]anthracene, benzo[b]fluoranthene, benzo[j]fluoranthene, benzo[k]fluoranthene, chrysene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene) show enough evidence of mutagenicity/genotoxicity in animal somatic cells in vivo to be considered as potentially genotoxic and carcinogenic to humans through the diet (EFSA, 2008).

Food is known as the main source of contamination by aromatic hydrocarbons for non-smokers (Menzie and Potocki, 1992). Contamination of raw products (animals and agricultural products) can occur during growth, transport, storage, and transformation (drying, grilling, roasting, smoking, and frying). Fruits and vegetables have usually a smaller aromatic hydrocarbon level than meat, probably due to their lower lipid content and their possible consumption as raw product. PAH contents (wet weight; w.w.) are respectively lower than 1 μg/kg and 4.1 μg/kg for fruits and vegetables from Catalonia, while their levels reach 365 μg/kg in meat (salami) (Martorell et al., 2010).

However, fruits and vegetables are consumed in large quantities and remain a considerable source of aromatic hydrocarbons. Fruits and vegetables consumption represents about 31% of the total food intake and is responsible for between 5 and 10% absorption of PAHs (Martorell et al., 2010). In the Czech Republic, PAH intake (sum of 12 PAHs) is estimated at 449 ng/day for apple (average annual consumption of 23.8 kg) (Jánská et al., 2006). Thus, contamination of fruits and vegetables by potentially carcinogenic aromatic hydrocarbons is a significant concern, and involves development of techniques to monitor these pollutants in such complex solid food matrices.

Most common methods for PAHs extraction in food are solvent extraction techniques. Ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and accelerated solvent extraction (ASE) have been notably used for PAH extraction from fish and meat products (Purcaro et al., 2009; Wang et al., 1999). These extraction procedures are most often followed by solid-phase extraction (SPE) as a clean-up step. Concerning fruits and vegetables, Soxhlet seems to remain a widely used technique for PAH extraction (Abou-Arab et al., 2014; Ashraf and Salam, 2012; Soceanu et al., 2014).

Less solvent consuming techniques, such as stir-bar sorptive extraction (SBSE) and solid-phase microextraction (SPME) by direct immersion or in the headspace (HS-SPME), are prevalent for extraction of the most volatile compounds in food matrices. HS-SPME and SBSE notably allow the assessment of benzene and toluene in cooked pork samples (Benet et al., 2015). HS-SPME technique provides concurrent monitoring of BTEX and PAHs up to four aromatic rings in olive oil (Vichi et al., 2005). SPME and HS-SPME techniques have also been used for the simultaneous recovery of BTEX and PAHs in liquid matrices. Direct immersion SPME, followed by an HS-SPME, step allows the determination of BTEX and heavy PAHs, such as dibenz[a,h]anthracene and benzo[ghi]perylene in Brazilian water (bottled, tap, and river water) (Bianchin et al., 2012). Nevertheless, until now, the simultaneous extraction of BTEX and total PAHs in complex matrices such as food remains challenging due to the difference in volatility between light and heavy aromatic hydrocarbons. The aim of this work, which is a development of existing protocols (Poinot et al., 2014), was to optimize and validate methodologies for aromatic hydrocarbons determination at trace level (μg/kg) in four different fruits (apple, pear, plum, and grape).

Section snippets

Chemical compounds evaluated

Acenaphthene (PubChem CID: 6734), acenaphthene-d10 (PubChem CID: 177559), acenaphthylene (PubChem CID: 9161), benz[a]anthracene (PubChem CID: 5954), benz[a]anthracene-d12 (PubChem CID: 12279531), benzene (PubChem CID: 241), benzo[a]pyrene (PubChem CID: 2336), benzo[b]fluoranthene (PubChem CID: 9153), benzo[ghi]perylene (PubChem CID: 9117), chrysene (PubChem CID: 9171), dibenz[a,h]anthracene (PubChem CID: 5889), ethylbenzene (PubChem CID: 7500), ethylbenzene-d10 (PubChem CID: 117648),

Methods optimization

Monitoring BTEX and PAHs requires different extraction and analysis techniques, due to their differences in volatility. We have previously developed and described methods for the dual determination of these compounds in apple (Poinot et al., 2014). Headspace solid-phase microextraction is efficient to recover BTEX and light PAHs while ultrasound-assisted extraction followed by solid-phase extraction allows the recovery of heavy PAHs at the ppm level (mg/kg). These methodologies were modified

Conclusion

Procedures using HS-SPME and UAE/SPE extraction and GC–MS analysis were modified and optimized to allow assessment of volatile and semi-volatile aromatic hydrocarbons (BTEX and PAHs) at the μg/kg level. Performances of methodologies were evaluated with apple. Measurements performed at 4 μg/kg were repeatable (RSD 1–22%) and precise (RSD 3–30%). Methods were, thus, validated for determination of aromatic hydrocarbons at trace amounts in apple and were extended to pear, plum, and grape.

Linearity

Funding

Alice Paris was supported by a Ph.D scholarship from the Basse-Normandie Region.

References (36)

  • M. Tankiewicz et al.

    Application and optimization of headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-flame-ionization detector (GC?FID) to determine products of the petroleum industry in aqueous samples

    Microchem. J.

    (2013)
  • S.P. Verevkin

    Vapor pressure measurements on fluorene and methyl-fluorenes

    Fluid Phase Equilib.

    (2004)
  • S. Vichi et al.

    Simultaneous determination of volatile and semi-volatile aromatic hydrocarbons in virgin olive oil by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry

    J. Chromatogr. A

    (2005)
  • A.A.K. Abou-Arab et al.

    Levels of polycyclic aromatic hydrocarbons (PAHS) in some Egyptian vegetables and fruits and their influences by some treatments

    Int. J. Curr. Microbiol. Appl. Sci.

    (2014)
  • M.W. Ashraf et al.

    Polycyclic aromatic hydrocarbons (PAHs) in vegetables and fruits produced in Saudi Arabia

    Bull. Environ. Contam. Toxicol.

    (2012)
  • N.R. Bishnoi et al.

    Quantification of polycyclic aromatic hydrocarbons in fruits and vegetables using high performance liquid chromatography

    Indian J. Chem. Technol.

    (2006)
  • M.C.R. Camargo et al.

    Polycyclic aromatic hydrocarbons in Brazilian vegetables and fruits

    Food Control

    (2003)
  • C. Crépineau-Ducoulombier et al.

    Assessment of soil and grass Polycyclic Aromatic Hydrocarbon (PAH) contamination levels in agricultural fields located near a motorway and an airport

    Agronomie

    (2003)
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