Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution
Identifieur interne : 001924 ( Istex/Corpus ); précédent : 001923; suivant : 001925Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution
Auteurs : Christa Schröter-Kermani ; Dirk Kreft ; Bernd Schilling ; Monika Herrchen ; Gerhard WagnerSource :
- Journal of Environmental Monitoring [ 1464-0325 ] ; 2006.
Abstract
In the framework of the German environmental specimen bank one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) serve as bioindicators for the atmospheric pollution. Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, ∑PAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g−1 wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g−1 ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to ∑PAH. The group of high molecular weight aromatics is dominated by benzo[b,j,k]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.
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DOI: 10.1039/b602382g
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Environ. Monit.</title><idno type="ISSN">1464-0325</idno><idno type="eISSN">1464-0333</idno><imprint><publisher>The Royal Society of Chemistry.</publisher><date type="published" when="2006">2006</date><biblScope unit="volume">8</biblScope><biblScope unit="issue">8</biblScope><biblScope unit="page" from="806">806</biblScope><biblScope unit="page" to="811">811</biblScope></imprint><idno type="ISSN">1464-0325</idno></series><idno type="istex">741F97B6D69AC489399D333FA808DBA1546417CA</idno><idno type="DOI">10.1039/b602382g</idno><idno type="ms-id">b602382g</idno></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">1464-0325</idno></seriesStmt></fileDesc><profileDesc><textClass></textClass><langUsage><language ident="en">en</language></langUsage></profileDesc></teiHeader><front><div type="abstract">In the framework of the German environmental specimen bank one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) serve as bioindicators for the atmospheric pollution. Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, ∑PAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g−1 wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g−1 ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to ∑PAH. The group of high molecular weight aromatics is dominated by benzo[b,j,k]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.</div></front></TEI><istex><corpusName>rsc-journals</corpusName><author><json:item><name>Christa Schröter-Kermani</name><affiliations><json:string>Federal Environmental Agency, D-06813, Dessau, Germany</json:string><json:string>E-mail: christa.schroeter-kermani@uba.de</json:string></affiliations></json:item><json:item><name>Dirk Kreft</name><affiliations><json:string>ERGO Forschungsgesellschaft mbH, D-22305, Hamburg, Germany</json:string><json:string>E-mail: dirk.kreft@ergo-research.com</json:string></affiliations></json:item><json:item><name>Bernd Schilling</name><affiliations><json:string>ERGO Forschungsgesellschaft mbH, D-22305, Hamburg, Germany</json:string><json:string>E-mail: dirk.kreft@ergo-research.com</json:string></affiliations></json:item><json:item><name>Monika Herrchen</name><affiliations><json:string>Fraunhofer IME, D-57377, Schmallenberg, Germany</json:string><json:string>E-mail: monika.herrchen@ime.fraunhofer.de</json:string></affiliations></json:item><json:item><name>Gerhard Wagner</name><affiliations><json:string>University Trier, D-54296</json:string><json:string>E-mail: wagnerg@uni-trier.de</json:string></affiliations></json:item></author><language><json:string>eng</json:string></language><originalGenre><json:string>ART</json:string></originalGenre><abstract>In the framework of the German environmental specimen bank one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) serve as bioindicators for the atmospheric pollution. Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, ∑PAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g−1 wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g−1 ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to ∑PAH. The group of high molecular weight aromatics is dominated by benzo[b,j,k]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.</abstract><qualityIndicators><score>7.916</score><pdfVersion>1.3</pdfVersion><pdfPageSize>595.276 x 779.528 pts</pdfPageSize><refBibsNative>true</refBibsNative><keywordCount>0</keywordCount><abstractCharCount>1483</abstractCharCount><pdfWordCount>3180</pdfWordCount><pdfCharCount>20638</pdfCharCount><pdfPageCount>6</pdfPageCount><abstractWordCount>228</abstractWordCount></qualityIndicators><title>Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution</title><refBibs><json:item><host><author></author><title>EMEP/MSC-E Technical Report 7/2005</title></host></json:item><json:item><host><author></author><title>EMEP/MSC-E Technical Report 7/2005</title></host></json:item><json:item><host><volume>16</volume><pages><last>254</last><first>245</first></pages><author></author><title>UWSF-Z Umweltchem. 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Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, ∑PAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g−1 wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g−1 ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to ∑PAH. The group of high molecular weight aromatics is dominated by benzo[b,j,k]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.</p></abstract></profileDesc><revisionDesc><change when="2006">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/741F97B6D69AC489399D333FA808DBA1546417CA/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="corpus rsc-journals not found" wicri:toSee="no header"><istex:xmlDeclaration>version="1.0" encoding="UTF-8"</istex:xmlDeclaration><istex:document><article type="ART" xsi:schemaLocation="http://www.rsc.org/schema/rscart38 http://www.rsc.org/schema/rscart38/rscart38.xsd" dtd="RSCART3.8"><metainfo><articletype code="ART" pubmedForm="research-article" headingForm="Papers" group="Paper" fullForm="Paper"></articletype></metainfo><art-admin><ms-id>b602382g</ms-id><doi>10.1039/b602382g</doi><received><date><year>2006</year><month>February</month><day>16</day></date></received><date role="accepted"><year>2006</year><month>July</month><day>7</day></date></art-admin><published type="web"><journalref><link>EM</link></journalref><volumeref><link>Unassigned</link></volumeref><issueref><link>Advance Articles</link></issueref><pubfront><fpage></fpage><lpage></lpage><no-of-pages></no-of-pages><date><year>2006</year><month>July</month><day>14</day></date></pubfront></published><published type="print"><journalref><link>EM</link></journalref><volumeref><link>8</link></volumeref><issueref><link>8</link></issueref><pubfront><fpage>806</fpage><lpage>811</lpage><no-of-pages>6</no-of-pages><date><year>2006</year><month>8</month><day>4</day></date></pubfront></published><published type="subsyear"><journalref><title type="abbreviated">J. 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Monit.</title><title type="full">Journal of Environmental Monitoring</title><title type="journal">Journal of Environmental Monitoring</title><title type="display">Journal of Environmental Monitoring</title><title type="pubmed">J Environ Monit</title><sercode>EM</sercode><publisher><orgname><nameelt>The Royal Society of Chemistry</nameelt></orgname></publisher><issn type="print">1464-0325</issn><issn type="online">1464-0333</issn><coden>JEMOFW</coden><cpyrt>This journal is © The Royal Society of Chemistry</cpyrt></journalref><volumeref><link></link></volumeref><issueref><link>8</link></issueref><pubfront><fpage></fpage><lpage></lpage><no-of-pages></no-of-pages><date><year>2006</year><month>Unassigned</month><day>Unassigned</day></date></pubfront></published><art-front><titlegrp><title>Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution<fnoteref idrefs="fn1"></fnoteref><footnote id="fn1">Presented at the International Environmental Specimen Bank Symposium, 14th–16th November 2005, Charleston, South Carolina, USA.</footnote></title></titlegrp><authgrp><author aff="affa" role="corres"><person><persname><fname>Christa</fname><surname>Schröter-Kermani</surname></persname></person></author><author aff="affb"><person><persname><fname>Dirk</fname><surname>Kreft</surname></persname></person></author><author aff="affb"><person><persname><fname>Bernd</fname><surname>Schilling</surname></persname></person></author><author aff="affc"><person><persname><fname>Monika</fname><surname>Herrchen</surname></persname></person></author><author aff="affd"><person><persname><fname>Gerhard</fname><surname>Wagner</surname></persname></person></author><aff id="affa"><org><orgname><nameelt>Federal Environmental Agency</nameelt></orgname></org><address><postcode>D-06813</postcode><city>Dessau</city><country>Germany</country></address><email>christa.schroeter-kermani@uba.de</email><fax>+49 340 2104 3217</fax><phone>+49 340 2103 3217</phone></aff><aff id="affb"><org><orgname><nameelt>ERGO Forschungsgesellschaft mbH</nameelt></orgname></org><address><postcode>D-22305</postcode><city>Hamburg</city><country>Germany</country></address><email>dirk.kreft@ergo-research.com</email><fax>+49 40 697096 99</fax><phone>+49 40 697096 48</phone></aff><aff id="affc"><org><orgname><nameelt>Fraunhofer IME</nameelt></orgname></org><address><postcode>D-57377</postcode><city>Schmallenberg</city><country>Germany</country></address><email>monika.herrchen@ime.fraunhofer.de</email><fax>+49 2972 302 319</fax><phone>+49 2972 302215</phone></aff><aff id="affd"><org><orgname><nameelt>University Trier</nameelt></orgname></org><address><postcode>D-54296</postcode></address><email>wagnerg@uni-trier.de</email><fax>+49 651 2014903</fax><phone>+49 651 2014687</phone></aff></authgrp><art-toc-entry><ictext>Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.</ictext><icgraphic xsrc="b602382g-ga.tif" id="ga"></icgraphic></art-toc-entry><abstract><p>In the framework of the German environmental specimen bank one-year old spruce shoots (<it>Picea abies</it>) and pine shoots (<it>Pinus sylvestris</it>) serve as bioindicators for the atmospheric pollution. Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, ∑PAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g<sup>−1</sup> wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g<sup>−1</sup> ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to ∑PAH. The group of high molecular weight aromatics is dominated by benzo[<it>b</it>,<it>j</it>,<it>k</it>]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.</p></abstract></art-front><art-body><section><title>Introduction</title><p>Polycyclic aromatic hydrocarbons (PAHs) constitute a large class of several hundred organic compounds. A negligible amount is released into the environment during production and processing of PAHs. Compounds found are used as intermediates to produce plasticizers, pigments, pesticides, and dyes. However, the largest emissions come from an incomplete combustion during industrial processes. The most important emission sources are coal coking, production of aluminium, domestic and residential heating, cooking, motor vehicle traffic, coal-fired power plant, forest fires, and incineration of refuse. Though the compounds can be degraded photolytically, and also can be removed by biodegradation and metabolism in higher biota the degradation rates are rather low for most of the substances. Thus they are characterized as being fairly persistent in the environment. In general, degradation tendencies in the environmental media are: air > water > soil > sediment.</p><p>Due to their lipophilic properties the compounds accumulate in soil, sediments, in soil living, aquatic, and sediment dwelling organisms as well as in natural products used as food. Biomagnification of PAHs has not been observed for any species since most of the organisms biotransform these chemicals. Organisms at higher trophic levels show the most pronounced biotransformation potential.</p><p>The occurrence of PAHs in the environment has been frequently subjected to monitoring programs and various surveillances.<citref idrefs="cit1">1</citref> In general, a PAH reduction over the last decades can be observed, though currently a plateau seems to be reached. For example, investigations of sediment cores revealed decreasing PAH deposition rates since the 1960s, but a stabilization on a relatively high level during the last decade.<citref idrefs="cit2 cit3">2,3</citref></p><p>In the framework of the German Environmental Specimen Bank (ESB)<citref idrefs="cit4">4</citref> PAHs are routinely analyzed in spruce and pine shoots. The shoots serve as passive samplers for airborne pollutants which are taken up rather <it>via</it> leaves or needles than <it>via</it> roots.<citref idrefs="cit5">5</citref> Recently, the stored material has been used to investigate temporal trends and spatial distribution of dioxins, furans, and PCBs in terrestrial ecosystems in Germany.<citref idrefs="cit6">6</citref> Some results regarding PAH monitoring in the ESB have been published previously, comprising mainly selected individual PAHs in shoots originating from urban areas.<citref idrefs="cit7">7</citref> Here exhaustive data sets are presented which cover the observation period 1985–2004 and allow comparisons of levels, patterns, and temporal trends of PAH in conifer shoots originating from different types of terrestrial ecosystems in Germany.</p></section><section><title>Experimental</title><subsect1><title>Selection of representative PAHs</title><p>From the several hundreds of individual PAHs a defined set of 17 aromatics has been choosen that represents 3 to 7 ring compounds (<tableref idrefs="tab1">Table 1</tableref>). Included are the six aromatic compounds listed in the German Drinking Water Ordinance, and 12 of 16 PAHs from the US EPA list. Also one substituted PAH benzo(<it>b</it>)naphto[2,1-<it>d</it>]thiophene was integrated because it is formed mainly by domestic heating.</p><table-entry id="tab1"><title>Investigated PAHs</title><table><tgroup cols="6"><colspec colnum="1" colname="1"></colspec><colspec colnum="2" colname="2"></colspec><colspec colnum="3" colname="3"></colspec><colspec colnum="4" colname="4"></colspec><colspec colnum="5" colname="5"></colspec><colspec colnum="6" colname="6"></colspec><thead><row><entry>Abbreviation</entry><entry>PAH</entry><entry>Number of rings</entry><entry>Molecular weight</entry><entry>Included in TWVO<fnoteref idrefs="tab1fna"></fnoteref></entry><entry>Included in US EPA list</entry></row></thead><tfoot><row><entry namest="1" nameend="6"><footnote id="tab1fna">German Drinking Water Ordinance.</footnote><footnote id="tab1fnb">Compounds used as deuterium labeled internal standard substances.</footnote><footnote id="tab1fnc">Not separated.</footnote></entry></row></tfoot><tbody><row><entry>PHE</entry><entry>Phenanthrene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>3</entry><entry>178</entry><entry></entry><entry>x</entry></row><row><entry>A</entry><entry>Anthracene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>3</entry><entry>178</entry><entry></entry><entry>x</entry></row><row><entry>FLU</entry><entry>Fluoranthene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>4</entry><entry>202</entry><entry>x</entry><entry>x</entry></row><row><entry>PYR</entry><entry>Pyrene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>4</entry><entry>202</entry><entry></entry><entry>x</entry></row><row><entry>B[<it>a</it>]A</entry><entry>Benz[<it>a</it>]anthracene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>4</entry><entry>228</entry><entry></entry><entry>x</entry></row><row><entry>CHR + TRI<fnoteref idrefs="tab1fnc"></fnoteref></entry><entry>Chrysene<fnoteref idrefs="tab1fnb"></fnoteref> + Triphenylene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>4</entry><entry>228</entry><entry></entry><entry>x (CHR)</entry></row><row><entry>B[<it>c</it>]PHE</entry><entry>Benzo[<it>c</it>]phenanthrene</entry><entry>4</entry><entry>228</entry><entry></entry><entry></entry></row><row><entry>2,1-BNT</entry><entry>Benzo[<it>b</it>]naphtho[2,1-<it>d</it>]thiophene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>4</entry><entry>234</entry><entry></entry><entry></entry></row><row><entry>B[<it>ghi</it>]FLU</entry><entry>Benzo[<it>ghi</it>]fluoranthene</entry><entry>5</entry><entry>226</entry><entry></entry><entry></entry></row><row><entry>BF[<it>b</it>,<it>j</it>,<it>k</it>]<fnoteref idrefs="tab1fnc"></fnoteref></entry><entry>Benzo[<it>b</it>,<it>j</it>,<it>k</it>]fluoranthene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>5</entry><entry>252</entry><entry>x (b + k)</entry><entry>x (b + k)</entry></row><row><entry>B[<it>e</it>]P</entry><entry>Benzo[<it>e</it>]pyrene</entry><entry>5</entry><entry>252</entry><entry></entry><entry></entry></row><row><entry>B[<it>a</it>]P</entry><entry>Benzo[<it>a</it>]pyrene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>5</entry><entry>252</entry><entry>x</entry><entry>x</entry></row><row><entry>DB[<it>a</it>,<it>h</it>]A<fnoteref idrefs="tab1fnc"></fnoteref></entry><entry>Dibenz[<it>a</it>,<it>h</it>]anthracene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>5</entry><entry>278</entry><entry></entry><entry>x</entry></row><row><entry>INP</entry><entry>Indeno[1,2,3-<it>cd</it>]pyrene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>6</entry><entry>276</entry><entry>x</entry><entry>x</entry></row><row><entry>B[<it>ghi</it>]P</entry><entry>Benzo[<it>ghi</it>]perylene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>6</entry><entry>276</entry><entry>x</entry><entry>x</entry></row><row><entry>ANT</entry><entry>Anthranthrene</entry><entry>6</entry><entry>276</entry><entry></entry><entry></entry></row><row><entry>COR</entry><entry>Coronene<fnoteref idrefs="tab1fnb"></fnoteref></entry><entry>7</entry><entry>300</entry><entry></entry><entry></entry></row></tbody></tgroup></table></table-entry></subsect1><subsect1><title>Samples</title><p>One-year old shoots of Scots pine (<it>Pinus sylvestris</it>) and Norway spruce (<it>Picea abies</it>) are collected and processed under well-defined and reproducible conditions according to standard operating procedures.<citref idrefs="cit8 cit9 cit10">8–10</citref> Thus, every precaution is taken to obtain representative samples of the same quality each year. The samples are characterized biometrically and frozen above liquid nitrogen on the spot. The material is stored as cryogenically homogenized and ground powder in sub-samples of approx. 10 g in the vapor phase above liquid nitrogen. Pine shoots have been collected since 1991 in Duebener Heide Mitte (U1), a forest in the urban-industrialized area of eastern Germany. Spruce shoots have been collected since 1985 in Warndt (U2), a forest in the urban-industrialized area of the Land Saarland in the south-west of Germany. Sampling of spruce shoots from seven different rural locations (R1–R7) from the north to the south of Germany started between the mid- to the end of the 1990s. All shoots were collected in February/March except the samples from two mountain areas (R5 and R7) from 2004 collected at the end of April/beginning of May due to large amounts of snow until early spring. The location of the sampling sites is shown in <figref idrefs="fig1">Fig. 1</figref>.</p><figure xsrc="b602382g-f1.tif" id="fig1"><title>Sampling locations of conifer shoots. Urban areas: U1, Duebener Heide Mitte; U2, Warndt/Saarland conurbation. Rural areas: R1, Bornhoeved; R2, Hochharz (∼700 m above sea level); R3, Solling (∼400 m a.s.l.); R4, Pfälzerwald (∼270 m a.s.l.); R5, Bayerischer Wald (1240 m a.s.l.); R6, Oberbayerisches Tertiärhügelland (∼500 m a.s.l.); R7, Berchtesgaden (∼1125 m a.s.l.).</title></figure></subsect1><subsect1><title>Analytical procedure</title><p>All analyses were performed following the isotope dilution method.<citref idrefs="cit7 cit8">7,8</citref> 17 native standards (substances see <tableref idrefs="tab1">Table 1</tableref>) were obtained from Cambridge Isotope Laboratories, Andover, USA. 14 internal deuterium-labeled standards (see substances marked with an asterix in <tableref idrefs="tab1">Table 1</tableref>) were delivered by Laboratory Dr Ehrensdorfer-Schäfers, Augsburg, Germany. Solvents were delivered by Merck (<it>n</it>-hexane, <it>N</it>,<it>N</it>-dimethylformamide), Mallinckrodt (toluene), Baker (acetone, cyclohexane, isopropanol). Silica gel, Sephadex LH-20 and sodium sulfate were obtained from Fluka.</p><p>A total of 5–10 g of herbal material was transferred into a 250 ml round bottomed flask and a mixture of 14 internal PAH standard substances (each with concentrations of 1 μg ml<sup>−1</sup>) was added. After a period of 15 minutes the addition of 150 ml acetone followed. The sample mixture was heated for 30 minutes under reflux and subsequently filtered. About 10 ml cyclohexane was added to the filtrate and it was concentrated on a rotary evaporator. The sample extract was transferred into a separating funnel and treated with 100 ml cyclohexane, 90 ml <it>N</it>,<it>N</it>-dimethylformamide and 10 ml water. After 3 min shaking the aqueous phase was separated and washed 2 more times with cyclohexane. In a second step the combined aqueous extracts were treated with 80 ml water and 100 ml cyclohexane and shaken in a separating funnel. The separated cyclohexane phase was extracted twice with water. The combined cyclohexane extracts were dried with sodium sulfate, filtered and concentrated by rotary evaporation.</p><p>Clean-up of the liquid extract was performed by silica gel and reversed-phase (Sephadex LH20) column. The final extract was reduced in volume by turbovap evaporation and subsequently by a stream of nitrogen. The final volume was 50 μl containing 5 μl benzo[<it>e</it>]pyrene-d<inf>12</inf> as injection standard substance for calculation of the recoveries.</p><p>The measurements were performed using high-resolution gas chromatography/ mass spectrometry (HRGC/MS, Agilent 6890 coupled with Agilent 5973 mass spectrometric detector) using a HP5MS column (50 m, 0.2 mm id, 0.33 μm film) for gas chromatographic separation. For measurement the two most abundant mass signals were used (for example: <it>m</it>/<it>z</it> 178 (M<sup>+</sup>) and <it>m</it>/<it>z</it> 176 (M<sup>+</sup> − 2) for phenanthrene). The identification of PAHs was based on retention time and fragment ion ratio. The quantification was performed using internal and external standard substances. Limits of detection of the target compounds were in the range 0.04–0.35 ng g<sup>−1</sup> wet weight (ww). For each annual homogenate 5–6 replicates were analysed. Data reported are means from these measurements; SDs are not shown but are in between the range of the measurement uncertainty estimated from replicate analyses (see <tableref idrefs="tab2">Table 2</tableref>).</p><table-entry id="tab2"><title>Statistical data from the validation procedure of the analytical method for a representative sample material (pine shoot homogenate Duebener Heide 1993, repeatability as relative standard deviation RSD; <it>n</it> = 10)</title><table><tgroup cols="3"><colspec colnum="1" colname="1"></colspec><colspec colnum="2" colname="2"></colspec><colspec colnum="3" colname="3"></colspec><thead><row><entry>PAH</entry><entry>Mean/ng g<sup>−1</sup> wet weight</entry><entry>RSD (%)</entry></row></thead><tbody><row><entry>PHE</entry><entry align="char" char=".">163</entry><entry align="char" char=".">3.0</entry></row><row><entry>A</entry><entry align="char" char=".">2.2</entry><entry align="char" char=".">34</entry></row><row><entry>FLU</entry><entry align="char" char=".">77</entry><entry align="char" char=".">2.0</entry></row><row><entry>PYR</entry><entry align="char" char=".">53</entry><entry align="char" char=".">3.4</entry></row><row><entry>B[<it>a</it>]A</entry><entry align="char" char=".">3.1</entry><entry align="char" char=".">4.4</entry></row><row><entry>CHR + TRI</entry><entry align="char" char=".">43</entry><entry align="char" char=".">2.6</entry></row><row><entry>B[<it>c</it>]PHE</entry><entry align="char" char=".">3.4</entry><entry align="char" char=".">4.8</entry></row><row><entry>2,1-BNT</entry><entry align="char" char=".">5.6</entry><entry align="char" char=".">22</entry></row><row><entry>B[<it>ghi</it>]FLU</entry><entry align="char" char=".">4.5</entry><entry align="char" char=".">6.3</entry></row><row><entry>BF[<it>b</it>,<it>j</it>,<it>k</it>]</entry><entry align="char" char=".">11</entry><entry align="char" char=".">3.2</entry></row><row><entry>B[<it>e</it>]P</entry><entry align="char" char=".">2.3</entry><entry align="char" char=".">7.0</entry></row><row><entry>B[<it>a</it>]P</entry><entry align="char" char=".">2.0</entry><entry align="char" char=".">6.3</entry></row><row><entry>DB[<it>a</it>,<it>h</it>]A</entry><entry align="char" char=".">0.4</entry><entry align="char" char=".">17</entry></row><row><entry>INP</entry><entry align="char" char=".">3.0</entry><entry align="char" char=".">3.9</entry></row><row><entry>B[<it>ghi</it>]P</entry><entry align="char" char=".">2.4</entry><entry align="char" char=".">6.0</entry></row><row><entry>ANT</entry><entry align="char" char=".">0.5</entry><entry align="char" char=".">23</entry></row><row><entry>COR</entry><entry align="char" char=".">1.6</entry><entry align="char" char=".">3.8</entry></row></tbody></tgroup></table></table-entry></subsect1><subsect1><title>Quality assurance measures</title><p>The measured range for the recovery of the added internal standards was 70–120%. The repeatability was tested by analysing multiple replicates of representative samples with PAH background concentrations (for typical data refer to <tableref idrefs="tab2">Table 2</tableref>). All solvents and reagents were tested before the laboratory procedures. All glassware was rinsed with solvents prior to use. Silica gel and sodium sulfate were pre-washed. For quality control a laboratory blank and a QC pool of pine shoots was performed with each batch of twelve samples. Quantification was only done when sample data was at least twice the blank value. For internal quality assurance certified or laboratory reference materials, and laboratory blanks were analyzed routinely. Furthermore, for external quality assurance the laboratory participated suscessfully in an interlaboratory testing scheme (QUASIMEME program, <url>http://www.quasimeme.org/</url>).</p><p>Mean PAH concentrations were calculated by using the respective value of the detection limit as concentration for non-detected compounds.</p></subsect1></section><section><title>Results and discussion</title><subsect1><title>PAH monitoring in the ESB program</title><p>The PAH measurements of conifer shoots were routinely performed in the year of the sampling of the material since the start of the environmental specimen bank program in 1985. Due to improvements in analytical technology a new method (HRGC/MS) was implemented in 2000. Besides a higher sensitivity that permits a restriction of the material to be analysed, this method has the further advantage of distinguishing between the two PAHs B[<it>c</it>]PHE and B[<it>ghi</it>]FLU that could not be separated with the former method (GC/MS).<citref idrefs="cit7 cit8">7,8</citref></p><p>Simultaneously to the establishment of HRGC/MS, retrospective analyses of several older samples were performed to ensure comparability of data sets. The results of the retrospectively analysed samples were in the range of the measurement uncertainty estimated from replicate analyses.</p></subsect1><subsect1><title>Current PAH concentrations and spatial distribution</title><p>PAH concentrations in conifer shoots sampled in 2004 or 2003 for the sites R1, R3, and R4, are listed in <tableref idrefs="tab3">Table 3</tableref>. The sum of the 17 individual aromatics analyzed (∑PAH) ranged from 8.2 to 61 ng g<sup>−1</sup> ww for the rural sites. Shoots from the two urban areas contained significantly higher ∑PAH amounts than shoots from the rural locations, namely 98 ng g<sup>−1</sup> ww and 121 ng g<sup>−1</sup> ww, respectively. Thus, the ratio of ∑PAH concentrations (urban) to ∑PAH concentrations (rural) is in between 1.6 and 14.8. The ratio between highest and lowest ∑PAH concentrations (rural) is 7.5 indicating large differences in the PAH burden of non-urban sampling sites. Data do not allow for general conclusions on the dependency of PAH concentrations on the latitude of sampling sites. This is true, though in spruce shoots originating from the three locations with the highest altitudes (R2, R5, and R7) lowest ∑PAH concentrations were detected.</p><table-entry id="tab3"><title>Current concentrations [ng g<sup>−1</sup> wet weight] of 17 individual PAHs and ∑PAH in conifer shoot samples</title><table><tgroup cols="10"><colspec colnum="1" colname="1"></colspec><colspec colnum="2" colname="2"></colspec><colspec colnum="3" colname="3"></colspec><colspec colnum="4" colname="4"></colspec><colspec colnum="5" colname="5"></colspec><colspec colnum="6" colname="6"></colspec><colspec colnum="7" colname="7"></colspec><colspec colnum="8" colname="8"></colspec><colspec colnum="9" colname="9"></colspec><colspec colnum="10" colname="10"></colspec><thead><row><entry colname="1" morerows="1" valign="bottom">PAH</entry><entry namest="2" nameend="10">Sites</entry></row><row><entry colname="2">U1</entry><entry colname="3">U2</entry><entry colname="4">R1</entry><entry colname="5">R2</entry><entry colname="6">R3</entry><entry colname="7">R4</entry><entry colname="8">R5</entry><entry colname="9">R6</entry><entry colname="10">R7</entry></row></thead><tbody><row><entry>PHE</entry><entry align="char" char=".">44</entry><entry align="char" char=".">35</entry><entry align="char" char=".">14</entry><entry align="char" char=".">6.2</entry><entry align="char" char=".">10</entry><entry align="char" char=".">13</entry><entry align="char" char=".">5.2</entry><entry align="char" char=".">20</entry><entry align="char" char=".">2.8</entry></row><row><entry>A</entry><entry align="char" char=".">0.50</entry><entry align="char" char=".">3.3</entry><entry align="char" char="."><0.3</entry><entry align="char" char="."><0.3</entry><entry align="char" char="."><0.3</entry><entry align="char" char="."><0.3</entry><entry align="char" char="."><0.3</entry><entry align="char" char=".">0.38</entry><entry align="char" char="."><0.3</entry></row><row><entry>FLU</entry><entry align="char" char=".">24</entry><entry align="char" char=".">26</entry><entry align="char" char=".">14</entry><entry align="char" char=".">4.4</entry><entry align="char" char=".">7.4</entry><entry align="char" char=".">8.4</entry><entry align="char" char=".">4.4</entry><entry align="char" char=".">15</entry><entry align="char" char=".">1.5</entry></row><row><entry>PYR</entry><entry align="char" char=".">9.7</entry><entry align="char" char=".">18</entry><entry align="char" char=".">8.2</entry><entry align="char" char=".">2.7</entry><entry align="char" char=".">4.1</entry><entry align="char" char=".">4.7</entry><entry align="char" char=".">2.8</entry><entry align="char" char=".">10</entry><entry align="char" char=".">0.79</entry></row><row><entry>B[<it>a</it>]A</entry><entry align="char" char=".">1.0</entry><entry align="char" char=".">2.6</entry><entry align="char" char=".">1.0</entry><entry align="char" char=".">0.29</entry><entry align="char" char=".">0.69</entry><entry align="char" char=".">0.50</entry><entry align="char" char=".">0.55</entry><entry align="char" char=".">0.70</entry><entry align="char" char="."><0.2</entry></row><row><entry>CHR + TRI</entry><entry align="char" char=".">7.9</entry><entry align="char" char=".">14</entry><entry align="char" char=".">7.5</entry><entry align="char" char=".">1.6</entry><entry align="char" char=".">3.8</entry><entry align="char" char=".">4.5</entry><entry align="char" char=".">2.3</entry><entry align="char" char=".">5.7</entry><entry align="char" char=".">0.55</entry></row><row><entry>B[<it>c</it>]PHE</entry><entry align="char" char=".">0.95</entry><entry align="char" char=".">1.4</entry><entry align="char" char=".">0.82</entry><entry align="char" char=".">0.16</entry><entry align="char" char=".">0.41</entry><entry align="char" char=".">0.42</entry><entry align="char" char=".">0.18</entry><entry align="char" char=".">0.71</entry><entry align="char" char="."><0.1</entry></row><row><entry>2,1-BNT</entry><entry align="char" char=".">0.60</entry><entry align="char" char=".">2.0</entry><entry align="char" char=".">0.59</entry><entry align="char" char=".">0.29</entry><entry align="char" char=".">0.42</entry><entry align="char" char=".">0.33</entry><entry align="char" char=".">0.28</entry><entry align="char" char=".">0.31</entry><entry align="char" char="."><0.1</entry></row><row><entry>B[<it>ghi</it>]FLU</entry><entry align="char" char=".">1.3</entry><entry align="char" char=".">1.6</entry><entry align="char" char=".">1.1</entry><entry align="char" char=".">0.25</entry><entry align="char" char=".">0.64</entry><entry align="char" char=".">0.64</entry><entry align="char" char=".">0.32</entry><entry align="char" char=".">1.1</entry><entry align="char" char=".">0.11</entry></row><row><entry>BF[<it>b</it>,<it>j</it>,<it>k</it>]</entry><entry align="char" char=".">4.5</entry><entry align="char" char=".">8.9</entry><entry align="char" char=".">4.1</entry><entry align="char" char=".">1.7</entry><entry align="char" char=".">3.8</entry><entry align="char" char=".">2.8</entry><entry align="char" char=".">3.4</entry><entry align="char" char=".">3.3</entry><entry align="char" char=".">0.76</entry></row><row><entry>B[<it>e</it>]P</entry><entry align="char" char=".">0.79</entry><entry align="char" char=".">1.9</entry><entry align="char" char=".">0.97</entry><entry align="char" char=".">0.34</entry><entry align="char" char=".">0.98</entry><entry align="char" char=".">0.53</entry><entry align="char" char=".">0.69</entry><entry align="char" char=".">0.66</entry><entry align="char" char=".">0.16</entry></row><row><entry>B[<it>a</it>]P</entry><entry align="char" char=".">0.77</entry><entry align="char" char=".">1.6</entry><entry align="char" char=".">0.80</entry><entry align="char" char=".">0.36</entry><entry align="char" char=".">0.80</entry><entry align="char" char=".">0.49</entry><entry align="char" char=".">0.86</entry><entry align="char" char=".">0.48</entry><entry align="char" char=".">0.19</entry></row><row><entry>DB[<it>a</it>,<it>h</it>]A</entry><entry align="char" char=".">0.30</entry><entry align="char" char=".">0.56</entry><entry align="char" char=".">0.32</entry><entry align="char" char=".">0.16</entry><entry align="char" char=".">0.28</entry><entry align="char" char=".">0.19</entry><entry align="char" char=".">0.30</entry><entry align="char" char=".">0.20</entry><entry align="char" char=".">0.06</entry></row><row><entry>INP</entry><entry align="char" char=".">1.0</entry><entry align="char" char=".">1.6</entry><entry align="char" char=".">0.88</entry><entry align="char" char=".">0.41</entry><entry align="char" char=".">1.1</entry><entry align="char" char=".">0.56</entry><entry align="char" char=".">1.0</entry><entry align="char" char=".">0.65</entry><entry align="char" char=".">0.21</entry></row><row><entry>B[<it>ghi</it>]P</entry><entry align="char" char=".">0.84</entry><entry align="char" char=".">1.9</entry><entry align="char" char=".">0.97</entry><entry align="char" char=".">0.45</entry><entry align="char" char=".">1.1</entry><entry align="char" char=".">0.62</entry><entry align="char" char=".">1.1</entry><entry align="char" char=".">0.84</entry><entry align="char" char="."><0.35</entry></row><row><entry>ANT</entry><entry align="char" char=".">0.12</entry><entry align="char" char=".">0.42</entry><entry align="char" char=".">0.13</entry><entry align="char" char=".">0.11</entry><entry align="char" char=".">0.18</entry><entry align="char" char=".">0.08</entry><entry align="char" char=".">0.27</entry><entry align="char" char=".">0.09</entry><entry align="char" char=".">0.04</entry></row><row><entry>COR</entry><entry align="char" char=".">0.45</entry><entry align="char" char=".">0.57</entry><entry align="char" char=".">0.36</entry><entry align="char" char=".">0.23</entry><entry align="char" char=".">0.45</entry><entry align="char" char=".">0.28</entry><entry align="char" char=".">0.42</entry><entry align="char" char=".">0.46</entry><entry align="char" char=".">0.11</entry></row><row><entry>∑PAH</entry><entry align="char" char=".">98</entry><entry align="char" char=".">121</entry><entry align="char" char=".">56</entry><entry align="char" char=".">20</entry><entry align="char" char=".">36</entry><entry align="char" char=".">38</entry><entry align="char" char=".">24</entry><entry align="char" char=".">61</entry><entry align="char" char=".">8.2</entry></row></tbody></tgroup></table></table-entry></subsect1><subsect1><title>Pattern of PAHs</title><p>The four lower molecular weight compounds PHE, FLU, PYR, and CHR/TRI dominated the ∑PAH burden in all samples independent from urban or rural influences (see <figref idrefs="fig2">Fig. 2</figref>).</p><figure xsrc="b602382g-f2.tif" id="fig2"><title>Percent contribution of individual PAHs.</title></figure><p>In pine shoots sampled at the Duebener Heide site (U1) these four compounds contributed 90% to ∑PAH with PHE accounting for nearly half of ∑PAH. Spruce shoots from the sampling site Warndt (U2) showed a different pattern: PHE, FLU, PYR, and CHR/TRI contributed about 80% to ∑PAH with concentrations descending in the order PHE > FLU > PYR > CHR/TRI. PHE accounted for approximately 30% of ∑PAH, <it>i.e.</it> a much lower amount compared to that of the sampling site U1. It is not yet clear whether these differences in PAH patterns depend on a species specific accumulation mechanism, or are due to different local PAH sources.</p><p>For the rural sampling sites the compounds PHE, FLU, PYR, and CHR/TRI contributed by about 60% (R5)–85% (R6) to ∑PAH. Concentrations descended in the order PHE > FLU > PYR > CHR/TRI. Thus, for all sites PHE is the main contributor with 22%–39% of the total PAH content.</p></subsect1><subsect1><title>Temporal trends</title><p>∑PAH concentrations in conifer shoots for the observation period 1985 to 2004 are shown in <figref idrefs="fig3">Fig. 3</figref>. It can be demonstrated impressively that for the urban sampling sites PAH burden decreased until the end of the 1990s/beginning of the 2000s by a factor of about 7 at the sampling site U1 and a factor of about 4 at the sampling site U2. Since then, a plateau on a fairly low level (around 100 ng g<sup>−1</sup> ww) has been reached. However, current PAH concentrations in conifer shoots sampled in remote areas are even lower by a factor of 2 to 10 (see <tableref idrefs="tab3">Table 3</tableref>).</p><figure xsrc="b602382g-f3.tif" id="fig3"><title>Temporal trend of ∑PAH in conifer shoots from two urban (U1,U2) and two remote (R2, R5) areas.</title></figure><p>Since continuous monitoring of spruce shoots in rural areas started not until the mid-1990s, available time series are relatively short and do not cover the period of extensive PAH reduction measures in Germany. Nevertheless, slightly decreasing levels are detectable in those samples too, as <it>e.g.</it> from 43 to 20 ng g<sup>−1</sup> ww between 1996 and 2004 in spruce shoots from the site R2.</p><p>Decrease of airborne PAHs in industrialized areas can be explained by the efficiency of emission reduction measures in the 1970s and 1980s. The urban sampling site U1 (Duebener Heide) shows much higher ∑PAH concentrations at the beginning of the respective sampling period (1991) compared to the urban site U2 (Warndt). The site U1 is situated in the former German Democratic Republic. After re-unification in 1989 most plants were either closed or modernized, and additionally, domestic heating technology was improved. Thus, the PAH emissions were reduced drastically to a level comparable to western Germany standards (sampling site U2).</p><p>A somewhat surprising result of these investigations is the finding that PAH patterns in conifer shoots from each area stay nearly constant over the years. This phenomenon is demonstrated for the two sampling sites U2 and R5. In <figref idrefs="fig4">Fig. 4</figref> the relative contribution of single compounds to ∑PAH in shoots are shown for selected years of the respective observation periods. Even in samples from the urban area U2 no significant changes in patterns are obvious, although concentrations decreased from 460 to 121 ng g<sup>−1</sup> ww between 1985 and 2004.</p><figure xsrc="b602382g-f4.tif" id="fig4"><title>Temporal trend of PAH patterns in spruce shoots from the urban site U2 and the remote site R5.</title></figure></subsect1><subsect1><title>Comparison with international results</title><p>Vegetation monitoring increasingly substitutes direct measurement of POPs in the air since there is a general assumption that the concentration of an analyte in the vegetation reflects the time-integrated concentration of the respective analyte in the air.<citref idrefs="cit5">5</citref></p><p>However, only few publications could be found which are to a certain extend methodically similar (conifers, exposure time, analysis of individual compounds). In 1994 a survey of PAH in pine needles sampled across the U.K. was performed.<citref idrefs="cit11">11</citref> The sum of sixteen individual PAH analysed (same as in this report except for 2,1-BNT) ranged from 19 to 3091 ng g<sup>−1</sup> dry weight (dw). At the same time highest concentrations of 804 ng g<sup>−1</sup> dw were detected in samples from the German urban area U1 and as such by a factor of about 3 lower than in the U.K.</p><p>Within an Austrian monitoring program exclusively remote forest sites were investigated in 1993.<citref idrefs="cit12">12</citref> Median concentrations of 48 ng g<sup>−1</sup> dw and a range of 28 to 412 ng g<sup>−1</sup> dw were determined in spruce needles. Whereas the median can be regarded as similar to German background values for this period (about 70 ng g<sup>−1</sup> dw in samples from the sites R2 and R5) it is noteworthy that the maximum PAH values of the investigated remote sites reach magnitudes found for the German urban area U2 in 1993 (660 ng g<sup>−1</sup> dw).</p><p>Both studies coincide with the ESB data in revealing that lower molecular (three to four ring) PAHs dominate the PAH burden of conifer shoot samples.</p><p>Two further monitorings offer data only for the compounds PHE, A, FLU, PYR, B[<it>a</it>]A, and CHR. The sum of this six compounds (∑<inf>6</inf>PAH) amounted 160 to 190 ng g<sup>−1</sup> dw in pine needles sampled in 2000 from remote sites in Poland.<citref idrefs="cit13">13</citref> These values are up to 5 times higher than ∑<inf>6</inf>PAH concentrations from remote German sites sampled in the same year (35 ng g<sup>−1</sup> dw in samples from R5, and 45 ng g<sup>−1</sup> dw in samples from R2). In 1997 spruce needles from remote and urban sites in eastern Alaska were analysed for the six PAHs.<citref idrefs="cit14">14</citref> The detected levels of 42 to 58 ng g<sup>−1</sup> dw in samples from remote areas were nearly identical to ESB data (35 and 51 ng g<sup>−1</sup> dw for the sites R5 and R2, respectively). However, urban concentrations of 128 ng g<sup>−1</sup> dw were significantly lower than in Germany (232 and 377 ng g<sup>−1</sup> dw for the sites U2 and U1, respectively).</p></subsect1></section><section><title>Conclusions</title><p>In the framework of the German environmental specimen bank one-year old spruce shoots (<it>Picea abies</it>) and pine shoots (<it>Pinus sylvestris</it>) served as bioindicators for the atmospheric pollution. Sampling was performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations.</p><p>Chemical analyses for 17 representative airborne PAHs for the sampling period 1985 to 2004 showed that ∑PAH concentrations in conifer shoots were highly variable. Elevated atmospheric concentrations in the industrialized areas in comparison with rural sites were reflected by the ESB results: concentrations in urban conifer shoots were significantly higher than in shoots sampled at the remote sites.</p><p>In urban areas a drastic decrease of PAH concentrations until the end of 1990s was observed indicating the efficiency of emission reduction measures.</p><p>The representative PAHs showed typical fingerprints. In all samples the pattern was dominated by the low molecular weight (three and four ring) substances. PAH patterns remained nearly unchanged during the investigated time period 1985 to 2004. It was not possible to identify specific emission sources such as oil refining or motor vehicle traffic and their reduction due to political measures.</p></section></art-body><art-back><ack><p>The authors acknowledge the funding of this project within the framework of the German Environmental Specimen Bank, which is financed by the German Federal Environment Ministry and organized by the Federal Environmental Agency.</p></ack><biblist><citgroup id="cit1"><citation type="book"><citauth><fname>V.</fname><surname>Shatalov</surname></citauth>, <citauth><fname>A.</fname><surname>Gusev</surname></citauth>, <citauth><fname>S.</fname><surname>Dutchak</surname></citauth>, <citauth><fname>I.</fname><surname>Holoubek</surname></citauth>, <citauth><fname>E.</fname><surname>Mantseva</surname></citauth>, <citauth><fname>O.</fname><surname>Rozovskaya</surname></citauth>, <citauth><fname>A.</fname><surname>Sweetman</surname></citauth>, <citauth><fname>B.</fname><surname>Strukov</surname></citauth>, and <citauth><fname>N.</fname><surname>Vulykh</surname></citauth>, <title>EMEP/MSC-E Technical Report 7/2005</title>, <url>http://www.emep.int/index_pollutants.html</url></citation></citgroup><citgroup id="cit2"><journalcit><citauth><fname>T.</fname><surname>Gocht</surname></citauth><citauth><fname>P.</fname><surname>Grathwohl</surname></citauth><title>UWSF-Z Umweltchem. 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S.</fname><surname>Howe</surname></citauth><citauth><fname>S.</fname><surname>Billings</surname></citauth><citauth><fname>R. J.</fname><surname>Stolzberg</surname></citauth><title>Environ. Sci. Technol.</title><year>2004</year><volumeno>38</volumeno><pages><fpage>3294</fpage><lpage>3298</lpage></pages></journalcit></citgroup></biblist><compoundgrp></compoundgrp><annotationgrp></annotationgrp><datagrp></datagrp><resourcegrp></resourcegrp></art-back></article></istex:document></istex:metadataXml><mods version="3.6"><titleInfo><title>Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution</title></titleInfo><titleInfo type="alternative" contentType="CDATA"><title>Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution</title></titleInfo><name type="personal"><namePart type="given">Christa</namePart><namePart type="family">Schröter-Kermani</namePart><affiliation>Federal Environmental Agency, D-06813, Dessau, Germany</affiliation><affiliation>E-mail: christa.schroeter-kermani@uba.de</affiliation></name><name type="personal"><namePart type="given">Dirk</namePart><namePart type="family">Kreft</namePart><affiliation>ERGO Forschungsgesellschaft mbH, D-22305, Hamburg, Germany</affiliation><affiliation>E-mail: dirk.kreft@ergo-research.com</affiliation></name><name type="personal"><namePart type="given">Bernd</namePart><namePart type="family">Schilling</namePart><affiliation>ERGO Forschungsgesellschaft mbH, D-22305, Hamburg, Germany</affiliation><affiliation>E-mail: dirk.kreft@ergo-research.com</affiliation></name><name type="personal"><namePart type="given">Monika</namePart><namePart type="family">Herrchen</namePart><affiliation>Fraunhofer IME, D-57377, Schmallenberg, Germany</affiliation><affiliation>E-mail: monika.herrchen@ime.fraunhofer.de</affiliation></name><name type="personal"><namePart type="given">Gerhard</namePart><namePart type="family">Wagner</namePart><affiliation>University Trier, D-54296</affiliation><affiliation>E-mail: wagnerg@uni-trier.de</affiliation></name><typeOfResource>text</typeOfResource><genre type="research-article" displayLabel="ART"></genre><originInfo><publisher>The Royal Society of Chemistry.</publisher><dateIssued encoding="w3cdtf">2006</dateIssued><copyrightDate encoding="w3cdtf">2006</copyrightDate></originInfo><language><languageTerm type="code" authority="iso639-2b">eng</languageTerm><languageTerm type="code" authority="rfc3066">en</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType></physicalDescription><abstract>In the framework of the German environmental specimen bank one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) serve as bioindicators for the atmospheric pollution. Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, ∑PAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g−1 wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g−1 ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to ∑PAH. The group of high molecular weight aromatics is dominated by benzo[b,j,k]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.</abstract><note type="footnote" displayLabel="fn1">Presented at the International Environmental Specimen Bank Symposium, 14th–16th November 2005, Charleston, South Carolina, USA.</note><note>Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004. [b602382g-ga.tif]</note><relatedItem type="host"><titleInfo><title>Journal of Environmental Monitoring</title></titleInfo><titleInfo type="abbreviated"><title>J. Environ. Monit.</title></titleInfo><genre type="journal">journal</genre><originInfo><publisher>The Royal Society of Chemistry.</publisher></originInfo><identifier type="ISSN">1464-0325</identifier><identifier type="eISSN">1464-0333</identifier><identifier type="coden">JEMOFW</identifier><identifier type="RSC sercode">EM</identifier><part><date>2006</date><detail type="volume"><caption>vol.</caption><number>8</number></detail><detail type="issue"><caption>no.</caption><number>8</number></detail><extent unit="pages"><start>806</start><end>811</end><total>6</total></extent></part></relatedItem><identifier type="istex">741F97B6D69AC489399D333FA808DBA1546417CA</identifier><identifier type="DOI">10.1039/b602382g</identifier><identifier type="ms-id">b602382g</identifier><accessCondition type="use and reproduction" contentType="copyright">This journal is © The Royal Society of Chemistry</accessCondition><recordInfo><recordContentSource>RSC Journals</recordContentSource><recordOrigin>The Royal Society of Chemistry</recordOrigin></recordInfo></mods></metadata><annexes><json:item><extension>gif</extension><original>true</original><mimetype>image/gif</mimetype><uri>https://api.istex.fr/document/741F97B6D69AC489399D333FA808DBA1546417CA/annexes/gif</uri></json:item></annexes><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
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|texte= Polycyclic aromatic hydrocarbons in pine and spruce shoots—temporal trends and spatial distribution
}}
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