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<article language="en">
	<journal>
		<journal_title>Atmospheric Chemistry and Physics</journal_title>
		<journal_url>www.atmos-chem-phys.net</journal_url>
		<issn>1680-7316</issn>
		<eissn>1680-7324</eissn>
		<volume_number>9</volume_number>
		<issue_number>17</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/acp-9-6479-2009</doi>
	<article_url>http://www.atmos-chem-phys.net/9/6479/2009/</article_url>
	<abstract_html>http://www.atmos-chem-phys.net/9/6479/2009/acp-9-6479-2009.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys.net/9/6479/2009/acp-9-6479-2009.pdf</fulltext_pdf>
	<start_page>6479</start_page>
	<end_page>6494</end_page>
	<publication_date>2009-09-08</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>
		</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 &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.</abstract>
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</article>

