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<article language="en">
	<journal>
		<journal_title>Atmospheric Chemistry and Physics Discussions</journal_title>
		<journal_url>www.atmos-chem-phys-discuss.net</journal_url>
		<issn>1680-7367</issn>
		<eissn>1680-7375</eissn>
		<volume_number>9</volume_number>
		<issue_number>2</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/acpd-9-5809-2009</doi>
	<article_url>http://www.atmos-chem-phys-discuss.net/9/5809/2009/</article_url>
	<abstract_html>http://www.atmos-chem-phys-discuss.net/9/5809/2009/acpd-9-5809-2009.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys-discuss.net/9/5809/2009/acpd-9-5809-2009.pdf</fulltext_pdf>
	<start_page>5809</start_page>
	<end_page>5852</end_page>
	<publication_date>2009-03-04</publication_date>
	<article_title content_type="html">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>
	<authors>
		<author numeration="1" affiliations="1">
			<name>A. Zambrano García</name>
			<email>azambran@imp.mx</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>C. Medina Coyotzin</name>
		</author>
		<author numeration="3" affiliations="1">
			<name>A. Rojas Amaro</name>
		</author>
		<author numeration="4" affiliations="1">
			<name>D. López Veneroni</name>
		</author>
		<author numeration="5" affiliations="2">
			<name>L. Chang Martínez</name>
		</author>
		<author numeration="6" affiliations="1">
			<name>G. Sosa Iglesias</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Dirección Ejecutiva de Investigación y Posgrado, Instituto  Mexicano del Petróleo,  México D.F., Mexico</affiliation>
		<affiliation numeration="2" content_type="html">Universidad Michoacana de San Nicolás de los Hidalgo, Morelia,  Mexico</affiliation>
	</affiliations>
	<abstract content_type="html">Mezquital Valley (MV), a Mexican wastewater-based agricultural and
      industrial region, is a &apos;&apos;hot spot&apos;&apos; 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 concentrations 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, 142.6–2568) 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;5.7 to
      &amp;minus;13.7&amp;permil;) was lower (&amp;lt;&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 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&lt;/i&gt;,&lt;i&gt;h&lt;/i&gt;,&lt;i&gt;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.</abstract>
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