Polycyclic aromatic hydrocarbons in smoked fish – a critical review

Among hundreds of components, wood smoke also contains at least 100 polycyclic aromatic hydrocarbons (PAH) and their alkylated derivatives. Many of them are carcinogenic. Benzo[α]pyrene (BaP) is regarded as a marker of the carcinogenic PAH in smoke and smoked fish, although in olive residual oil the maximum level of 2 μg/kg for each of the eight most carcinogenic PAHs, including BaP, has been set. Contemporary analytical procedures based on extraction of the hydrocarbons from the matrix, clean-up procedure, separation by gas chromatography (GC) or high performance liquid chromatography (HPLC), followed by detection and quantification by mass spectrometry (MS) or fluorescence detectors (FLD), respectively, make it possible to determine individual PAH in smoked foods at concentrations of the order of 0.1 μg/kg or even 0.01 μg/kg. Heavily smoked fish from traditional kilns, especially their outer parts, may contain up to about 50 μg BaP/kg wet weight, while the meat of mild hot-smoked fish, from smokehouses supplied with conditioned wood smoke from external generators, contains only about 0.1 μg/kg, or even less. Some older data on the contents of BaP in smoked fish should be treated with caution, if the analytical procedures used did not guarantee unequivocal separation and identification of the individual PAH.     

Polycyclic aromatic hydrocarbons in German smoked meat products

The contents of the 15+1 EU priority PAH were analysed from 113 representative commercial smoked German meat products collected in the year 2006 with a Fast-GC/HRMS method. The median of benzo[a]pyrene content was 0.03 μg/kg and therefore greater than a factor of 100 below the maximum level of 5 μg/kg. The highest content of benzo[a]pyrene was detected in a Frankfurter-type sausage (0.43 μg/kg). The sum content of benzo[a]pyrene, benzo[a]anthracene, chrysene and benzo[b]fluoranthene (“PAH4”), as proposed by the European Food Safety Authority to be a good marker for PAH in food, was 0.28 μg/kg in median, and the sum content of the 15+1 EU priority PAH was 0.64 μg/kg in median. The analysed smoked meat products showed an increasing presence of PAH in the following order: cooked ham (n = 17) < raw sausages (n = 25) < liver sausages (n = 25) < raw ham (n = 23) < Frankfurter-type sausages (n = 23). The correlation coefficient (R) between BaP and the sum of the 15+1 EU priority PAH was 0.90. To increase the safety of the consumer, a lowering of the BaP maximum level to 1 μg/kg is proposed and critical aspects using “PAH4” as a marker for PAH in food surveillance are discussed.     

Polycyclic aromatic hydrocarbons in traditionally smoked Slavonska kobasica

ABSTRACT

The traditional smoking procedure, which is the use of open fire, can lead to the formation of PAHs in sausages. The aim of this paper was to assess the types and concentrations of 16 PAHs in 30 samples of Slavonska kobasica, a traditional smoked sausage. In general, some samples showed high values of anthracene and acenaphthylene. In one sample, acenaphthylene reached the value of 1050 µg/kg and in another 1491 µg/kg anthracene was measured. Cancerogenic benzo(a)pyrene content was little above the maximum limit of 5 µg/kg in four samples, but mainly remained below the limit of quantification. PAH4 (i.c. benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo(a)pyrene) were above the maximum limit of 30 µg/kg in three samples. Generally, it can be noted from the results that samples with high PAH4 and benzo(a)pyrene concentrations also have high PAH16 concentrations.     

Polycyclic aromatic hydrocarbons in meat smoked with different types of wood

The influence of the wood used for the smoking of meat on the formation of polycyclic aromatic hydrocarbons (PAH) has been studied. Ten types of wood and charcoal were used for preparation of smoked meat samples. The analytical sample preparation method implied extraction of PAH with cyclohexane, liquid–liquid extraction with N,N-dimethylformamide/water, back extraction with cyclohexane, followed by clean-up on silica solid phase extraction (SPE) column and quantification by gas chromatography–mass spectrometry. It was found that the type of wood has a significant influence on the amount of PAH in smoked meat. The samples smoked with apple-tree and alder contained the smallest PAH concentrations. The samples smoked with spruce had the highest concentrations of PAH. The difference in content of benzo[a]pyrene (from 6.04 till 35.07 μg/kg) and total PAH (from 47.94 till 470.91 μg/kg) indicates that choice of wood for smoking is one of the critical parameter to be controlled in order to diminish the contamination of food products.     

Polycyclic aromatic hydrocarbons and halogenated persistent organic pollutants in canned fish and seafood products: smoked versus non-smoked products

In this study, levels of several groups of environmental contaminants represented by PAHs, PCBs, organochlorine pesticides and polybrominated diphenyl ethers were determined in various types of canned smoked and non-smoked fish and seafood products (54 samples) obtained from the Czech market. PAHs were detected in all of the studied samples, and at least one of the target halogenated persistent organic pollutants was present above the LOQ in 85% of the samples. The levels of PAHs, PCBs, organochlorine pesticides (mainly DDTs) and polybrominated diphenyl ethers found in the canned products varied in the range of 1.4–116?µg?kg^?1, 0.6–59.6?µg?kg^?1, 0.6–82.7?µg?kg^?1 and 0.1–2.1?µg?kg^?1 can content, respectively. Smoked sprats were the most contaminated fish product (n?=?12) in which the highest levels of both PAHs and persistent organic pollutants were found. In 67% of the samples of smoked sprats in oil, the level of benzo[a]pyrene exceeded the maximum level of 5?µg?kg^?1 established for smoked fish by European Union legislation. The distribution of target analytes between oil and fish fractions was also assessed. Significantly higher levels of PAHs were measured in the oil fraction.     

Polycyclic aromatic hydrocarbons (PAHs) in different types of smoked meat products from Serbia

The contents of the16 EU priority PAHs in six different meat products from Serbia (beef ham, pork ham, bacon without skin, bacon with skin, cajna sausage and sremska sausage) were examined during the process of smoking. All these meat products from meat industry Zlatiborac, Mačkat, Serbia presented in this study, have not previously been analysed concerning to their contents of PAH compounds. Determination and quantification of PAHs in meat products were performed by a Fast GC/HRMS method. The maximum level for benzo[a]pyrene (BaP) of 5 μg/kg in smoked meat products was not exceeded in any samples. BaP comprises in general 4.6% of the total sum of the 16 EU priority PAHs and 15.2% of the total sum of the 12 IARC PAH compounds. The suitability of BaP as a marker both for 16 EU priority PAHs and 12 IARC probably and possibly carcinogenic PAHs was checked by applying correlation analysis.     

Occurrence of polycyclic aromatic hydrocarbons in smoked cheese

The presence of polycyclic aromatic hydrocarbons (PAH) in smoked cheeses of different origin was studied. The samples were subjected to an initial extraction of fat and an alkaline treatment, extracted with cyclohexane, cleaned up by means of solid-phase extraction tubes, and analyzed by gas chromatography/mass spectrometry (GC/MS) operating in selective ion-monitoring mode (SIM). The results revealed the presence of numerous polycyclic aromatic hydrocarbons in the exterior zone of the samples, some of them with methyl groups. In all cases, the concentrations of compounds of low molecular weight were much higher than those of high molecular weight. Polycyclic aromatic hydrocarbons with varying degrees of carcinogenicity were identified, including benzo(a)pyrene in concentrations, which, although they did not exceed the limit established for this compound in the rind of ripened cheeses, do exceed the limit of 0.03 microg/kg fixed for other foods smoked with smoke flavorings. Significant differences in the number and concentration of PAH in smoked cheese also were observed from rind to interior, the rind being the most contaminated zone.     

Polycyclic aromatic hydrocarbons (PAHs) in traditional and industrial smoked beef and pork ham from Serbia

Smoked beef and pork ham samples were analysed during process of smoking (after packing and storing) for the presence of the 16 EU priority PAHs via Fast GC/HRMS method. This study showed that there are differences in PAH contents between final smoked beef ham samples from traditional smokehouse (TS) (3.9 μg kg⁻¹) and industrial smokehouse (IS), (1.9 μg kg⁻¹). Also there is a difference in PAH contents in final smoked pork ham samples (4.9 μg kg⁻¹, TS; 4.2 μg kg⁻¹, IS). In beef and pork ham samples from the same smokehouse different PAH contents were observed during smoking. The highest content of examined PAHs in all beef and pork ham samples during smoking showed benzo[c]fluorene (BcL) (beef ham: from 0.3 μg kg⁻¹ to 1.5 μg kg⁻¹; pork ham: from 0.2 μg kg⁻¹ to 2.1 μg kg⁻¹).The maximum level for benzo[a]pyrene (BaP) of 5 μg kg⁻¹ in smoked meat products was not exceeded in any samples. Correlation statistic analysis (P < 0.05) of obtained contents from samples both from TS and IS showed that BaP is a good marker both for 16 EU priority PAHs and 12 IARC probably and possibly carcinogenic PAHs (IS: R _BaP/Σ16PAHs = 0.95, R _BaP/Σ12PAHs = 0.96; TS: R _BaP/Σ16PAHs = 0.71, R _BaP/Σ12PAHs = 0.88).     

Research Watch: Polycyclic aromatic hydrocarbons

Sediments.     

Research Watch: Polycyclic aromatic hydrocarbons

Air.     

Research Watch: Polycyclic aromatic hydrocarbons

Sediments.     

Polycyclic aromatic hydrocarbons in the bakery chain

The level of polycyclic aromatic hydrocarbons occurrence and the possibility of their formation in the bakery chain, its raw materials and final products, were examined. Experimental bread baking, with different baking temperatures, was performed in the Warsaw bakery, using cyclothermic deck ovens. PAHs determination was performed by high-pressure liquid chromatography with fluorescent and diode array detectors (HPLC–FLD/DAD) and confirmed by gas chromatography coupled with mass spectrometry (GC/MS). Total content of 19 PAHs in the grain, flour and bran varied from 1.07 to 3.65 μg/kg and, in bread, from 1.59 to 13.6 μg/kg depending on the part of bread and baking temperature. Based on the dough’s contamination level and the influence of the baking temperature on the bread’s PAHs content, it was confirmed that PAHs are formed during baking. Considering the results of the average dietary exposure to PAHs and the MOE (Margin of Exposure) analysis, it could be concluded that analysed bread and cereal products constitute little concern for consumer health.     

Polycyclic aromatic hydrocarbons in frying oils and snacks

The high incidence of lung cancer observed among Chinese women has been associated with exposure to fumes from cooking oil. Polycyclic aromatic hydrocarbons (PAHs) are a class of potentially mutagenic substances emitted from cooking oils heated at high temperatures. The objective of this study was to investigate whether deep frying with different oils under different conditions leads to the development of PAHs either in the oil or in the fried product (snacks). PAH analysis was carried out with solid-phase extraction followed by reverse-phase high-performance liquid chromatography and spectrofluorometric detection. Different oils were used to fry chips and extruded snacks in different industrial plants (continuous frying) at temperatures between 170 and 205 degrees C, and peanut oil was used to fry French fries and fish (discontinuous frying) at temperatures between 160 and 185 degrees C. No appreciable differences in PAH load was observed in the same oil before and after frying. Both before and after frying, the benzo[a]pyrene concentration in oils ranged from trace to 0.7 ppb. All the analyzed samples, including oils from fried snacks, had benzo[a]pyrene concentrations well below the 2 ppb limit recently proposed by the European Community.     

烟熏肉制品中多环芳烃的提取及检测分析

烟熏肉制品作为肉类加工制品的一大类,由于其独特的风味深受广大消费者的欢迎。但是,在烟熏肉中含有致癌的多环芳烃(PAHs),影响着人们的健康。主要从烟熏肉制品中多环芳烃(PAHs)的提取、检测方法对其进行综述,以实现多环芳烃的快速检测和达到寻找控制多环芳烃方法的目的。     

Polycyclic aromatic hydrocarbons,polychlorinated biphenyls,chlorinated pesticides (DDTs), hexachlorocyclohexane,and hexachlorobenzene residues in smoked seafood

Smoked seafoods were screened for the presence of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and other organochlorine compounds. Total PAH concentrations ranged from 46.5 ng/g (wet weight) for smoked swordfish to 124.0 ng/g (wet weight) for smoked herring. Among the carcinogenic PAHs, benzo(a)pyrene ranged from undetectable levels for several smoked fish to 0.7 ng/g for Scottish salmon, dibenzo(ah)anthracene was not present in any of the samples analyzed, and benzo(a)anthracene was found in all samples and at particularly high levels in salmon (23.2 ng/g). Benzo(a)pyrene concentrations were below the tolerance limit for all samples. PCB concentrations for the different samples ranged from 2 to 30 ng/g. Chlorinated pesticides (DDTs: p,p'-DDE, p,p'-DDT, o,p'-DDT, p,p'-DDD, and o,p'-DDD) were detected at levels ranging from 0.2 ng/g (wet weight) in bluefin tuna to 17.5 ng/g (wet weight) in salmon. Hexachlorocyclohexane isomers (alphaHCH + betaHCH + gammaHCH) were present in higher amounts in eels (6.5 ng/g) than in the other smoked fish. For 40% of the samples, PCB concentrations exceeded the limit fixed by the European Union, while pesticide levels were below the maximum acceptable limit proposed by the Food and Agriculture Organization.     

Determination of polycyclic aromatic hydrocarbons (PAHs) in commonly consumed Nigerian smoked/grilled fish and meat

Smoking and/or grilling, when carried out with traditional methods involving direct contact with wood combustion fumes, is responsible for high contamination levels with carcinogenic polycyclic aromatic hydrocarbons (PAHs). The aim of this work was to investigate the PAH content of different smoked or grilled meat and fish products commonly consumed in Nigeria. A rapid method involving microwave-assisted saponification and simultaneous extraction followed by solid-phase extraction (SPE), high-performance liquid chromatography (HPLC) separation and spectrofluorometric detection was employed. Samples that were smoked or grilled using traditional systems, which use a wood fire, were heavily contaminated with benzo[a]pyrene (BaP) at levels ranging from 2.4 to 31.2 µg kg^?1 wet weight. Considerably lower contamination levels were found in samples smoked or grilled in the laboratory using a charcoal fire (BaP from 0.7 to 2.8 µg kg^?1 wet weight). The health risk associated with a daily consumption of 100 g of these products was also evaluated using the margin of exposure (MOE) approach. MOE values lower than 10,000 were obtained for all smoked/grilled commercial samples, indicating a potential concern for consumer health.     

Influence of smoking parameters on the concentration of polycyclic aromatic hydrocarbons (PAHs) in Danish smoked fish

A new method for the analysis of 25 polycyclic aromatic hydrocarbon (PAH) compounds in fish was developed, validated, and used for the quantification of PAHs in 180 industrially smoked fish products. The method included pressurized liquid extraction, gel-permeation chromatography (Bio-beads S-X3), solid-phase extraction (silica gel), and gas chromatography-mass spectrometry analysis. The sum concentration of 25 PAHs (∑PAH₂₅) was highest in smoked herring (n = 3) and mackerel fillets (n = 13), with an average concentration of 320 and 235 µg kg^?1, respectively. Lowest average ∑PAH₂₅ concentrations were obtained for indirectly smoked trout (26 µg kg^?1). Principal component analysis was used to correlate processing parameters to PAH concentrations and to identify the effects of these parameters. The analysis showed that for salmon hot-smoking conditions lead to higher ΣPAH₂₅ than cold smoking, and for other fish species direct smoking leads to higher ΣPAH₂₅ than indirect smoking. Also, the usage of common alder increases the PAH contamination compared with beech. The effects of smoking time, combustion temperatures, and two types of smoke-generating material on the ∑PAH₂₅ were also tested in a pilot plant study with smoked trout as a model fish. In addition to confirming that increased combustion temperatures and usage of common alder in comparison with beech increased ∑PAH₂₅, it was also revealed that the PAH concentration decreased in the order fish skin ? outer layer of the fish muscle > inner part of the fish muscle.     

Polycyclic aromatic hydrocarbons in stormwater runoff from sealcoated pavements

Coal-tar based sealcoat has been identified as a source of polycyclic aromatic hydrocarbons (PAHs) in the environment. This study measured the long-term release of PAHs in parking lot runoff and found that the presence of coal tar sealant increased the mass of PAHs released in runoff by over an order of magnitude. PAH concentrations in stormwater from two coal tar sealed parking lots and one unsealed parking lot (control) were monitored over a two-year period. The measured flow volume and concentrations were used to calculate a mass of 9.8-10.8 kg total Σ16 PAHs per hectare exported in stormwater runoff from the two sealed parking lots and 0.34 kg total Σ16 PAHs per hectare from the unsealed control. The study also measured sediment PAH concentration changes in a receiving drainage and found that even partial coverage of a drainage area by coal tar sealant resulted in measurable increases in PAH sediment concentrations; PAH concentrations in sediment in a stormwater swale receiving runoff from both sealed and unsealed lots increased near the outfall from less than 4 mg/kg prior to sealing to 95.7 mg/kg after sealing. Compound ratio plots and principal components analysis were examined and were able to clearly differentiate between pre- and postsealant samples.     

Polycyclic aromatic hydrocarbons (PAHs) in sugarcane juice

Sugarcane juice is a common beverage in many Brazilian cities. At harvesting season most sugarcane plantation is burnt and this procedure has been shown as an important source of PAHs emission. In the present study 80 samples of sugarcane juice collected from two Brazilian cities, in two different periods, were analysed for the presence of four PAHs: benz(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene and benzo(a)pyrene. PAHs were detected in 50% of the samples. The samples collected between harvests presented mean sums of PAHs of 0.013 μg/kg and 0.012 μg/kg, while the samples collected during harvest presented mean sums of 0.053 μg/kg and 0.055 μg/kg. A higher concentration and incidence of PAHs in the juices collected in the harvest period was verified, corroborating the burning of the crops as a source of sugarcane juice contamination.