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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-8-111-2008</article-id>
<title-group>
<article-title>PM speciation and sources in Mexico during the MILAGRO-2006 Campaign</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Querol</surname>
<given-names>X.</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>Pey</surname>
<given-names>J.</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>Minguillón</surname>
<given-names>M. 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>Pérez</surname>
<given-names>N.</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>Alastuey</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>Viana</surname>
<given-names>M.</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>Moreno</surname>
<given-names>T.</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>Bernabé</surname>
<given-names>R. M.</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>Blanco</surname>
<given-names>S.</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>Cárdenas</surname>
<given-names>B.</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>Vega</surname>
<given-names>E.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sosa</surname>
<given-names>G.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Escalona</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ruiz</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Artíñano</surname>
<given-names>B.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Instituto de Ciencias de la Tierra &quot;Jaume Almera&quot;, CSIC. C/ Lluís Solé i Sabarís s/n, 08028 Barcelona, Spain</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Centro Nacional de Investigación y Capacitación Ambiental, CENICA. Periférico 5000, Col. Insurgentes Cuicuilco, C.P. 04530, Delegación Coyoacán, Mexico D.F., Mexico</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas 152, Col. San Bartolo Atepehuacan. Delegación Gustavo A. Madero. 07730, Mexico, D.F, Mexico</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>CIEMAT, Avda. Complutense 22, 28040 Madrid, Spain</addr-line>
</aff>
<pub-date pub-type="epub">
<day>14</day>
<month>01</month>
<year>2008</year>
</pub-date>
<volume>8</volume>
<issue>1</issue>
<fpage>111</fpage>
<lpage>128</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/8/111/2008/acp-8-111-2008.html">This article is available from http://www.atmos-chem-phys.net/8/111/2008/acp-8-111-2008.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/8/111/2008/acp-8-111-2008.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/111/2008/acp-8-111-2008.pdf</self-uri>
<abstract>
<p>Levels of PM&lt;sub&gt;10&lt;/sub&gt;, PM&lt;sub&gt;2.5&lt;/sub&gt; and PM&lt;sub&gt;1&lt;/sub&gt; and chemical speciation of
PM&lt;sub&gt;10&lt;/sub&gt; and PM&lt;sub&gt;2.5&lt;/sub&gt; were measured during the MILAGRO campaign (1st
to 31st March 2006, but extended in some cases until 6th April) at
four urban, one suburban, two rural background and two rural sites, with
different degree of industrial influence, in the Mexico City Metropolitan
Area (MCMA) and adjacent regions. PM&lt;sub&gt;10&lt;/sub&gt; and PM&lt;sub&gt;2.5&lt;/sub&gt; daily levels
varied between 50&amp;ndash;56μg/m&lt;sup&gt;3&lt;/sup&gt; and 24&amp;ndash;46μg/m&lt;sup&gt;3&lt;/sup&gt; at the urban
sites, 22&amp;ndash;35μg/m&lt;sup&gt;3&lt;/sup&gt; and 13&amp;ndash;25μg/m&lt;sup&gt;3&lt;/sup&gt; at the rural sites,
and 75μg/m&lt;sup&gt;3&lt;/sup&gt; and 31μg/m&lt;sup&gt;3&lt;/sup&gt; at the industrial hotspot, lower than those recorded at some Asian mega-cities and
similar to those recorded at other Latin American cities. At the urban
sites, hourly PM&lt;sub&gt;2.5&lt;/sub&gt; and PM&lt;sub&gt;1&lt;/sub&gt; concentrations showed a marked impact
of road traffic emissions (at rush hours), with levels of coarse PM
remaining elevated during daytime. At the suburban and rural sites
different PM daily patterns were registered according to the influence of
the pollution plume from MCMA, and also of local soil resuspension.
&lt;br&gt;&lt;br&gt;
The speciation studies showed that mineral matter accounted for 25&amp;ndash;27%
of bulk PM&lt;sub&gt;10&lt;/sub&gt; at the urban sites and a higher proportion (up to 43%)
at the suburban and rural sites. This pattern is repeated in PM&lt;sub&gt;2.5&lt;/sub&gt;,
with 15% at urban and 28% at suburban and rural sites. Carbonaceous
compounds accounted for a significant proportion at the urban and industrial
sites (32&amp;ndash;46% in PM&lt;sub&gt;10&lt;/sub&gt;, and 51&amp;ndash;55% in PM&lt;sub&gt;2.5&lt;/sub&gt;), markedly
reduced at the suburban and rural sites (16&amp;ndash;23% in PM&lt;sub&gt;10&lt;/sub&gt;, and 30%
in PM&lt;sub&gt;2.5&lt;/sub&gt;). The secondary inorganic aerosols accounted for 10&amp;ndash;20% of
bulk PM&lt;sub&gt;10&lt;/sub&gt; at urban, suburban, rural and industrial sites, with a higher
proportion (40%) at the industrial background site. A relatively high
proportion of nitrate in rural sites was present in the coarse fraction.
&lt;br&gt;&lt;br&gt;
Typically anthropogenic elements (As, Cr, Zn, Cu, Pb, Sn, Sb, Ba, among
others) showed considerably high levels at the urban sites; however levels
of particulate Hg and crustal trace elements (Rb, Ti, La, Sc, Ga) were
generally higher at the suburban site.
&lt;br&gt;&lt;br&gt;
Principal component analysis identified three major common factors: crustal,
regional background and road traffic. Moreover, some specific factors were
obtained for each site.</p>
</abstract>
<counts><page-count count="18"/></counts>
</article-meta>
</front>
<body/>
<back>
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