Polycyclic Aromatic Hydrocarbons Determination in Grilled Beef and Chicken

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are principally formed as a result of thermal treatment of food, especially grilling or barbecuing. In the present study, two types of Iranian popular grilled beef and chicken dishes (kebab) were analyzed for toxic PAHs, i.e., naphthalene, fluoranthene, phenanthtrene, anthracene, pyrene, and benzo(a)pyrene applying GC/MS. The differences in PAHs concentrations among grilled beef and chicken (kebab koobide and juje kebab) were found to be significant (p < 0.05), ranging from 0.29 to 21.95 ng·g^?1. Benzo(a)pyrene was found in nearly all samples; the maximum concentration of total PAHs was 21.95 ng·g^?1 found in grilled beef (koobide Khalij fars) and the lowest was 0.29 ng·g^?1 in grilled chicken (juje kebab) of Sahel restaurant.     

Ozonation of Polycyclic Aromatic Hydrocarbons in Water Solution

The degradation of three polycyclic aromatic hydrocarbons (PAHs): benzo[a]pyrene (BAP), chrysene (CHR), and fluorene (FLU) in aqueous solution using ozone was investigated. The influence of pH of the reaction mixture, ozone concentration, and the presence of a radical scavenger on the reaction rate was determined. The highest rate of PAHs disappearance was achieved in acidic solutions. The radical scavenger, tert-butanol, effectively inhibited the rate of PAHs destruction. The rate constants of direct reaction of PAHs with ozone were calculated and they were equal to (3.32 ± 0.21) × 10⁴; (1.10 ± 0.15) × 10⁴ and 44.8 ± 1.1 M^?1s^?1 for BAP, CHR, and FLU, respectively. The contributions of direct ozonolysis, and radical reaction to PAHs oxidation in ozonation processes, were evaluated.     

Analysis by GC-MS of Polycyclic Aromatic Hydrocarbons in a Cream Containing Coal Tar

Qualitative and quantitative PAHs composition of a cream containing coal tar (5%), used in cutaneous diseases treatment, was studied. Eleven PAHs were analysed in pure coal tar and in the cream by GC-MS, after ultrasonic extraction by pyridine. Ten PAHs were found in pure coal tar: naphthalene, biphenyl, acenaphthylene, fluorene, phenanthrene, anthracene, carbazole, fluoranthene, pyrene and benzo[a]pyrene. No traces of 2,3-benzofluorene were detected. Seven PAHs were identified in the cream: naphthalene, biphenyl, acenaphthylene, fluorene, phenanthrene, fluoranthene and pyrene. 2,3-benzofluorene was also absent in the cream. Anthracene, carbazole and benzo[a]pyrene (one of the most toxic) were present in coal tar and not detected in the cream.

The seven PAHs found in the cream and in coal tar were quantified. Hydrocarbons concentrations were between 0.107 ± 0.0038 mg.g^?1 (for biphenyl) and 0.734 ± 0.0438 mg.g^?1 (for phenanthrene) in the cream and between 4.31 ± 0.23 mg.g^?1 (for biphenyl) and 21.9 ± 0.57 mg.g^?1 (for fluorene) in coal tar.     

Distribution,Sources, and Risk of Polycyclic Aromatic Hydrocarbons in the Core Sediments from Baiyangdian Lake,China

The burial characteristics and risks of 16 polycyclic aromatic hydrocarbons (PAHs) in core sediments from Baiyangdian Lake were investigated through gas-chromato graphy/mass spectrometry. The total concentrations of the 16 PAHs ranged from 39.48–1877.75 ng g^?1. The low-molecular-weight PAHs (two- to three-ring PAHs) were the dominant species, contributing 40.10–92.18% to the total PAHs, with a mean of 71.01%. Based on the observed molecular indices and on principal component analysis, the PAHs inputs were initially dominated by biomass and coal combustion, and atmospheric deposition and surface runoff could be the major transport pathways. The contaminated source characteristics, hydrodynamic condition, and sediment textural composition are the key factors affecting the distribution and source of PAHs. By conducting a risk quotient analysis between specific PAH concentrations and their corresponding sediment quality values, the top layer sediments were found to have a potential biological impact and relatively high toxicity. However, such impact should have no impairment. The toxic potency of PAHs in Baiyangdian Lake could be described by using the toxic equivalent of benzo[a]pyrene.     

Seasonal and Spatial Variation of Polycyclic Aromatic Hydrocarbons in Vapor-Phase and PM2.5 in Southern California Urban and Rural Communities

Fifteen priority polycyclic aromatic hydrocarbons (PAHs) were measured in two rural communities (Atascadero and Lompoc) located several hundred km northwest of Los Angeles and in four urban communities 40–100 km downwind of Los Angeles (San Dimas, Upland, Mira Loma, and Riverside), during all seasons, from May 2001 to July 2002. PM_2.5 and vapor-phase PAHs were collected, on prebaked quartz fiber filters and PUF-XAD-4 resin, respectively, at 113 LPM, during 24 h periods, every eighth day, and quantified by HPLC-Fluorescence. At all sites vapor-phase PAHs contained > 99.9% of the total PAH mass and were dominated by naphthalene (NAP), which varied from about 60 ng m ^{? 3} in Lompoc, a community with light traffic, to ～580 ng m ^{? 3} in Riverside, a community traversed by ～200,000 vehicles day^{? 1}. During summer pollution episodes in urban sites, NAP concentrations reached 7–30 times annual averages. Except for summer episodes, concentrations of low MW PAHs showed small seasonal variations (～2 times higher in winter). Similar concentrations of particle-phase PAHs were observed at all sites except for Lompoc. Benzo[ghi]perylene (BGP), a marker of gasoline exhaust emissions, showed the highest concentration among particle-phase PAHs, varying from 23.3 pg m^?3 in Lompoc to 193 pg m^?3 in Mira Loma. Benzo[a]pyrene and indeno[1,2,3-cd]pyrene, found exclusively in the particle phase, were much higher in urban sites (～40–100 pg m^?3), than in Lompoc (～12 pg m^?3). Winter particle-phase PAHs were 2 to 14 times higher than summer levels. Particle-phase PAHs were negatively correlated with mean air temperature in urban sites (r = ?0.50 to ?0.75), probably resulting from surface inversions occurring during winter. The data suggest that in Southern California vehicular exhaust emissions are a major contributor to particle-phase PAHs.     

Contamination of Soil by Polycyclic Aromatic Hydrocarbons in Some Urban Areas

The contamination by 16 polycyclic aromatic hydrocarbons (PAHs) in surface soils, sampled at a 0-5 cm depth in the urban areas of Tallinn, Helsinki, Vilnius, Chicago, London is reported. All samples were analyzed using the same protocol. The median concentrations ( w g/kg) were found to be 117, 539, 127, 3,263, 1,728 for pyrene; 62, 236, 43, 1,634, 1,652 for benzo[ a ]pyrene; 86, 304, 92, 2,295, 2,068 for benzo[ a ]pyrene toxic equivalents, calculated using the benzo[ a ]pyrene toxic equivalency factors; 467, 1,471, 392, 8,981, 6,837 for a total of seven probable human carcinogenic PAHs: benzo[ a ]anthracene, chrysene, benzo[ b ]fluoranthene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, dibenz[ ah ]anthracene, indeno[1,2,3- cd ]pyrene; 911, 2,941, 672, 16,183, 13,718 for the total of 16 PAHs, recommended by the U.S. Environmental Protection Agency: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[ a ]anthracene, chrysene, benzo[ b ]fluoranthene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, dibenz[ ah ]anthracene, benzo[ ghi ]perylene, indeno[1,2,3- cd ]pyrene in Tallinn ( n = 3), Helsinki ( n = 3), Vilnius ( n = 15), Chicago ( n = 4), London ( n = 3), respectively. The size of the population is a statistically significant factor in urban soil contamination by high-molecular-mass PAHs.     

Occurrence and Source Apportionment of Polycyclic Aromatic Hydrocarbons in Urban Residential Soils from National Capital Region,Uttar Pradesh,India

This study aims to investigate the level of priority polycyclic aromatic hydrocarbons (PAHs) and identification of their potential sources in residential soils. During the study, a total 36 soil samples collected from twelve residential locations at Sahibabad-Ghaziabad area of western Uttar Pradesh, India, a constituted part of the National Capital Region of India. Samples extracted using ultrasonication, cleaned with silica and analyzed by diode array detector–high-performance liquid chromatography using acetonitrile/water as mobile phase. The 25th and 75th percentile concentration of ∑PAHs was 264 μg kg^?1 and 584 μg kg^?1, respectively, with mean and median of 445 μg kg^?1 and 421 μg kg^?1. The detection frequency of PAHs in all samples was lower for low molecular weight PAHs (19%) than high molecular weight PAHs (81%). The concentration of seven probable carcinogenic PAHs accounted for 67% of the ∑PAHs. PAHs toxicity potential as benzo(a)pyrene toxicity equivalent ranged between 2.52–253 μg BaP_TEQ kg^?1. Composition profile of PAHs with different aromatic rings and selected diagnostic molecular ratios suggested the local pyrogenic sources of PAHs from vehicular emissions, diesel engines, biomass combustion, gasoline, and coal combustions.     

Source Apportionment and Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Surface Sediments from Upper Reach of Huaihe River,China

Fifteen priority PAHs in 16 sediments from upper reach of Huaihe River collected in 2007 were measured. Source apportionment derived from PCA/MLR indicated that the highest contribution to ΣPAHs was from biomass burning (34.1%), followed by coal combustion (29.7%), vehicular emission (25.8%), and coke oven origin (10.4%). Risk assessment for each identified source was quantitatively calculated by combining the benzo[a]pyrene equivalent (BaPE) with estimated source contribution. The results showed that coal combustion posed the highest toxic risk, with BaPE value of 13.1 ng g^?1 dw, and the BaPE values for biomass burning, vehicular emission and coke oven were 5.6 ng g^?1 dw, 7.8 ng g^?1 dw, and 4.1 ng g^?1 dw, respectively. The distributions of contribution for total PAHs burden and BaPE of each identified source showed similar pattern among different sampling sites.     

Interference of Soil Contaminants with Laccase Activity During the Transformation of Complex Mixtures of Polycyclic Aromatic Hydrocarbons in Liquid Media

The biotransformation of 16 polycyclic aromatic hydrocarbons (PAHs) in mixture was investigated in reactors in the presence of purified laccases of the fungus Pycnoporus cinnabarinus, ABTS as a redox mediator, 25% acetonitrile, and Tween 20. Several hydrocarbons from a synthetic mixture, such as anthracene and benzo[ a ]pyrene, were converted up to 80% into quinones, whereas others also belonging to three- and five-ring chemicals were less transformed. Chrysene and benzo[ k ]fluoranthene were not oxidized by the laccase mediator system. Moreover, hydrocarbons extracted from an industrial soil were all recalcitrant to enzymatic attack. This lack of reactivity of the laccases toward the hydrocarbons could be due to the presence of interfering compounds coextracted from the soil, such as metals.     

Determination of Averaged Long-term Air Concentrations of Semivolatile Polycyclic Aromatic Hydrocarbons: First Results

Abstract

Using our long-term sampling methodology presented previously, consecutive 14-day air samples of semivolatile polycyclic aromatic hydrocarbons (PAH) (from fluoranthene/pyrene to coronene) were collected over the time-span of nearly a whole year at a semi-rural site (Jülich) and quantified by GC-FID. As expected, concentrations were higher in winter [3 ng m^?3 for benzo[e]pyrene (BEP)] than in summer (0.4 ng m^?3 for BEP). However, normalized concentrations (to BEP =1) showed constant values for most PAH; thus, a largely stable PAH profile is obvious. Exceptions are benzo[a]pyrene and benz[a]anthracene: their concentrations normalized to BEP were lower in summer, indicating specific losses. Reasons for these losses are unknown as yet, although degradation reactions during atmospheric transport are a distinct possibility.     

Monitoring and Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in the Atmosphere of Alexandria City,Egypt

The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in the total suspended particulate (TSP) were measured simultaneously between January 30, 2015 and February 11, 2016 at urban, suburb, and rural sites at Alexandria City, Egypt, using pesticide samplers. Samples were extracted and analyzed using chromatography–mass spectrometric (GC–MS). There was a significant difference in concentrations between the three sites, and between particle- and vapor-phases. Mean total PAH concentrations were 502.48, 322.57, and 417.23 ng m^?3 for the urban, the rural, and the suburban sites in particulate-phase and were 723.49, 402.26, and 543.15 for the same sites in vapor-phase, respectively. At the three sites, the most abundant compounds determined were Benzo[k]fluoranthene (BkF), followed by Benzo[a]pyrene (BaP) and Indeno [1,2,3-cd] pyrene (IcdP). These high molecular weight compounds are carcinogenic and known to originate mainly from vehicular emissions. The diagnostic ratios indicated PAHs in urban and suburban sites were predominantly from gasoline and diesel engines, while that in rural site was from biomass burning. Characterization of the emission sources was further substantiated by significant correlation between individual PAH species.     

Monitoring of Polycyclic Aromatic Hydrocarbons in Water during Preparation Processes

This article presents results on investigation of quantitative changes of polycyclic aromatic hydrocarbons (PAHs) during water treatment processes. PAHs constitute one of several classes of organic pollutants consisting of three or more fused benzene rings. Many of them are quite persistent and some are known to be carcinogens. That is why presentation of quantitative PAHs changes in water during preparation processes is very important. In Polish legislation and European Union law there are recommendations for PAHs concentration in drinking water. The limit value of the sum of 4 PAHs (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[g,h,i]perylene, indeno[1,2,3-cd]pyrene) is 100 ng/L. Limit concentration of benzo[a]pyrene defined in regulations (Polish and UE) is 10 ng/L. The purpose of the present study was to determine changes of concentrations of PAHs in various stages of water treatment process and comparison the values of this index with the limits specified in valid Minister of Health Regulation and Council Directive 98/83/EC. A total concentration of 16 PAHs in the investigated water treatment processes was in the range of 39–204 ng/L. The maximum level was recorded for water after intermediate ozonation. In different water treatment processes were observed fluctuations in PAHs concentrations. Decreased values were recorded among others after pre-ozonation and coagulation and after sedimentation process. Increase of PAHs level occurred after filtration through sand filters. Concentrations of 4 PAHs in drinking water is much below the limit value defined in Polish and UE legislation. Concentration of 16 PAHs in water after final chlorine-disinfection also meets the requirements of the regulation for 4 PAHs.     

不同加热模式对山茶油中多环芳烃累积的影响

采用凝胶渗透色谱净化,结合气相色谱-质谱法对山茶油加热过程中累积的18种多环芳烃残留进行了检测。对不同加热模式(加热时长、加热次数、加热温度)对山茶油中多环芳烃累积的影响进行了考察,结果表明:当加热时长为6 h,重复加热次数为12,加热温度200℃接近山茶油烟点时,山茶油中的PAHs总量为183.389μg/kg,其中苯并[b]荧蒽、苯并[a]芘和苯并[g,h,i]苝这三种高致癌性PAHs含量达到本实验的最大值。加热时长延伸、重复加热次数增多或加热温度提升均对山茶油中PAHs的累积有明显促进作用。     

Mangrove Oyster (Crassostrea belcheri) as a Biomonitor Species for Bioavailability of Polycyclic Aromatic Hydrocarbons (PAHs) from Sediment of the West Coast of Peninsular Malaysia

ABSTRACT

Rapid industrialization and urbanization in the west coast of Peninsular Malaysia has caused increasing pollution particularly of petroleum and petroleum by-products. Surface sediment and mangrove oyster (Crassostrea belcheri) were collected from five mangrove ecosystems in the west coast of Peninsular Malaysia and investigated for bioavailability of polycyclic aromatic hydrocarbons (PAHs). Sampling locations were selected from both remote areas with few or no previous records of petroleum pollution such as Pulau Merambong and polluted areas that are under international attention such as Klang mangrove ecosystem. PAH fractions were obtained through soxhlet extraction and two-step column chromatography and the fractions were injected to gas chromatography-mass spectrometry (GC-MS) for analysis. The concentrations of PAHs ranged from 151 to 4973 ng g^?1 dw in the sediments, while from 309 to 2225 ng g^?1 dw in the oysters. When tested for diagnostic ratios, a predominance of pyrogenic source PAHs was detected in the sediments, whereas PAHs in the oysters had mixed petrogenic and pyrogenic sources. A significant correlation (p < 0.05) was found between high molecular weight (HMW) PAHs in the sediments and oysters and biota accumulation factors (BAFs) of PAHs were approaching or exceeding unity indicating the ability of mangrove oyster in bioaccumulation of PAHs. Overall, this study indicates that mangrove oyster (C. belcheri) can be used as a biomonitor species for PAHs in an aquatic environment.     

Characterization and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Surface Water from Liaohe River,Northeast China

ABSTRACT

In this study, the characteristics, probable source, and potential carcinogenic risk of 16 polycyclic aromatic hydrocarbons (PAHs) in surface water of the Liaohe River were investigated. Twelve sampling points were selected, and water samples were collected in both dry and flood periods of 2011. Sample analysis indicated that the concentration of total PAHs varied from 840.50 ng/L to 4274.73 ng/L in the flood period, and from 387.76 ng/L to 1997.83 ng/L in the dry period. The representative PAHs in the flood period were benz[a]anthracene (Baa), naphthalene (Nap), and chrysene (Chr), whereas Phenanthrene (Phe), fluoranthene (Flu), and pyrene (Pyr) were the representative PAHs in the dry period. The compositional pattern of PAHs indicated that four-ring PAHs were predominant in the flood period, whereas three-ring and four-ring PAHs dominated in the dry period. The different PAH congener ratios indicated that PAHs in surface water of the Liaohe River mainly originated from a mixed source in the flood period, and from combustion in the dry period. Based on the methods of Incremental Lifetime Cancer Risk (ILCR) and the benzo[a]pyrene toxic equivalent (TEQ), the potential cancer risk was quantitatively assessed, and the results suggested that there was a potential cancer risk in surface water of the Liaohe River and more attentions must be paid to the PAHs contamination. The cancer risk in the teenager group was the most, followed by the children group, adult group, and infant group, and toddler group was the least.     

Polycyclic Aromatic Hydrocarbons in Romanian Baby Foods and Fruits

Levels of polycyclic aromatic hydrocarbons (PAHs) in commercially available baby food and in different sorts of fruits were investigated. PAHs determination was performed by gas chromatography coupled with mass spectrometry (GC/MS). The sum of 15 PAHs varied in baby food from 2.52–6.7 μg/kg and in fruits from 0.40–21.52 μg/kg. Benzo[a]pyrene used as a marker for PAHs contamination was detected in lower levels in baby food than the maximum tolerable limit (1 μg/kg) stated in Commission Regulation no 1881/2006.     

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

ABSTRACT

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 (PA-H8). 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 PAH2.     

Indoor Polycyclic Aromatic Hydrocarbon Concentration in Central India

The indoor burning of different materials like fuels, incense, mosquito coil, candles etc. results in generation of polycyclic aromatic hydrocarbons (PAHs) in an uncontrolled manner. The PAH, i.e., Benzo(a)pyrene (BaP) is considered as most toxic or carcinogenic and the toxicity of other PAHs is related to this compound. Therefore, the concentration and emission fluxes of polycyclic aromatic hydrocarbons (PAHs) emitted during burning of commonly used indoor materials, i.e., 15 fuels (i.e., biomass (BM), coal (C), cow dung (CD), kerosene (K)), 4 incense (IS) and mosquito coil (MC) in Raipur district, Chhattisgarh, central India is described. The samples were taken in September 2013 in indoor environments and respective smoke emitted were collected using high volume United State of America (USA) air sampler on quartz fiber filters. The concentration of total 13 PAHs (∑PAH₁₃) (i.e., phenanthrene, anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)-pyrene, dibenz(ah)anthracene, benzo(ghi) perylene, indeno1,2,3-(cd)pyrene, and coronene) in particulate matter (PM₁₀) in the indoor air during burning of the fuels, IS and MC materials ranged from 367–92052 ng m^?3, 4089–14047 ng m^?3, and 66–103 ng m^?3 with mean values of 7767 ± 11809 ng m^?3, 9977 ± 4137 ng m^?3, and 74 ± 20 ng m^?3, respectively. The mean concentration of the ∑PAH₁₃ present in indoor environment is much higher than the WHO limit value of 1.0 ng m^?3. The sources and toxicities of PAHs are discussed.     

Evaluation of Polycyclic Aromatic Hydrocarbons Contamination in the Sediments of the Johor Strait,Peninsular Malaysia

In May 2013, sediment samples were collected from five stations in the Straits of Johor, near the southern tip of Peninsular Malaysia, in order to evaluate the distribution and sources of polycyclic aromatic hydrocarbons (PAHs). The concentrations of 16 United States Environmental Protection Agency PAHs varied from 650.5 to 1441.2 ng g ^?1 dry weight (dw) with a mean value of 985.5 ng g ^?1 dw. PAHs can be classified as moderate level pollution in the collected samples. When comparing PAHs in this study with that of the sediment quality guidelines (SQGs), it was found that the total PAHs, low molecular weight (LMW), and high molecular weight (HMW) PAHs might incur minimal adverse biological effects. The diagnostic ratios of individual PAHs indicated both petrogenic and pyrogenic origins with predominantly pyrogenic sources, the findings of which are further supported by the results from principal component analysis (PCA). The PCA results reveal contributions of 44.44%, 32.3%, and 18.96% for traffic-related, coal combustion, and petroleum-related products, respectively. These findings indicate that the effective monitoring and significant improvement resulting from the implementation of environmental regulations in Malaysia might have caused a shift in the source of petroleum hydrocarbons in the Straits of Johor's aquatic ecosystems from petrogenic to pyrogenic origins.     

HYDROCARBON POLLUTION ALONG MOROCCAN COASTS AND BPH ACTIVITY IN THE MUSSEL PERNA PERNA

Specimens of the mussel Perna perna were collected along Moroccan coasts to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) bioaccumulated in the tissues, and to measure benzo[a]pyrene hydroxylase (BPH) activity. Chemical analysis of PAHs show that the Mediterranean (Nador, Martil, Tanger) and central Atlantic coasts (from Rabat to Jorf Lihoudi) are those most contaminated (351 245 ng.g^{? 1} dry weight in Tanger). The mussel contaminants were of mixed origin for most of the locations with non negligible inputs of petrogenic origin in many of them. Baseline levels of PAHs were between 6 and 55 ng.g^{? 1} dry weight. BPH activity showed significant correlation (r _s = 0.64, P < 0.05) with total PAH concentrations at the six most contaminated stations. The baseline level of BPH activity can be identified as in the range 0.1 to 13 pmol.min^{? 1}.mg prot^{? 1} along the Mediterranean and Atlantic coasts.