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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACP</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACP</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7324</issn>
<publisher><publisher-name>Copernicus GmbH</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-9-6479-2009</article-id>
<title-group>
<article-title>Distribution and sources of bioaccumulative air pollutants at Mezquital Valley, Mexico, as reflected by the atmospheric plant &lt;i&gt;Tillandsia recurvata&lt;/i&gt; L.</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zambrano García</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Medina Coyotzin</surname>
<given-names>C.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rojas Amaro</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>López Veneroni</surname>
<given-names>D.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Chang Martínez</surname>
<given-names>L.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sosa Iglesias</surname>
<given-names>G.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Dirección Ejecutiva de Investigación y Posgrado, Instituto Mexicano del Petróleo, México D.F., Mexico</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Universidad Michoacana de San Nicolás de los Hidalgo, Morelia, Mexico</addr-line>
</aff>
<pub-date pub-type="epub">
<day>08</day>
<month>09</month>
<year>2009</year>
</pub-date>
<volume>9</volume>
<issue>17</issue>
<fpage>6479</fpage>
<lpage>6494</lpage>
<permissions>
<license xlink:type="simple">
<license-p>This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</license-p>
</license>
</permissions>
<self-uri xlink:href="http://www.atmos-chem-phys.net/9/6479/2009/acp-9-6479-2009.html">This article is available from http://www.atmos-chem-phys.net/9/6479/2009/acp-9-6479-2009.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/9/6479/2009/acp-9-6479-2009.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/9/6479/2009/acp-9-6479-2009.pdf</self-uri>
<abstract>
<p>Mezquital Valley (MV), a Mexican wastewater-based agricultural and industrial
region, is a &quot;hot spot&quot; of regulated air pollutants emissions, but the
concurrent unregulated ones, like hazardous metals and polycyclic aromatic
hydrocarbons (PAH), remain undocumented. A biomonitoring survey with the
epiphytic &lt;i&gt;Tillandsia recurvata&lt;/i&gt; was conducted there to detect spatial
patterns and potential sources of 20 airborne elements and 15 PAH. The
natural &amp;delta;&lt;sup&gt;13&lt;/sup&gt;C and &amp;delta;&lt;sup&gt;15&lt;/sup&gt;N ratios of this plant helped in
source identification. The regional mean concentration of most elements was
two (Cr) to over 40 times (Ni, Pb, V) higher than reported for
&lt;i&gt;Tillandsia&lt;/i&gt; in other countries. Eleven elements, pyrene and chrysene
had 18–214% higher mean concentration at the industrial south than at the
agricultural north of MV. The total quantified PAH (mean, 572 ng g&lt;sup&gt;&amp;minus;1&lt;/sup&gt;;
range, 143–2568) were composed by medium (65%, phenanthrene to chrysene),
low (28%, naphthalene to fluorene) and high molecular weight compounds (7%,
Benzo(&lt;i&gt;b&lt;/i&gt;)fluoranthene to indeno(1,2,3-&lt;i&gt;cd&lt;/i&gt;)pyrene). The
&amp;delta;&lt;sup&gt;13&lt;/sup&gt;C (mean, &amp;minus;14.6&amp;permil;; range, &amp;minus;15.7&amp;permil; to
&amp;minus;13.7&amp;permil;) was consistently lower than &amp;minus;15&amp;permil; near the major
petroleum combustion sources. The &amp;delta;&lt;sup&gt;15&lt;/sup&gt;N (mean, &amp;minus;3.0&amp;permil;; range,
&amp;minus;9.9&amp;permil; to 3.3&amp;permil;) varied from positive at agriculture/industrial
areas to negative at rural sites. Factor analysis provided a five-factor
solution for 74% of the data variance: 1) crustal rocks, 39.5% (Al, Ba, Cu,
Fe, Sr, Ti); 2) soils, 11.3%, contrasting contributions from natural (Mg,
Mn, Zn) and saline agriculture soils (Na); 3) cement production and fossil
fuel combustion, 9.8% (Ca, Ni, V, chrysene, pyrene); 4) probable
agricultural biomass burning, 8.1% (K and benzo(&lt;i&gt;g,h,i&lt;/i&gt;)perylene), and 5)
agriculture with wastewater, 5.2% (&amp;delta;&lt;sup&gt;15&lt;/sup&gt;N and P). These results
indicated high deposition of bioaccumulative air pollutants at MV, especially
at the industrial area. Since &lt;i&gt;T. recurvata&lt;/i&gt; reflected the regional
differences in exposition, it is recommended as a biomonitor for comparisons
within and among countries where it is distributed: southern USA to
Argentina.</p>
</abstract>
<counts><page-count count="16"/></counts>
</article-meta>
</front>
<body/>
<back>
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