ARSENIC AND HEAVY METAL POLLUTION OF SOIL, WATER AND
SEDIMENTS IN A SEMI-ARID CLIMATE MINING AREA IN MEXICO
, LETICIA CARRIZALES
and MARCOS MONROY
Instituto de Metalurgia, U.A.S.L.P., San Luis Potosí, S.L.P., México;
Laboratorio de Toxicología
Ambiental, Facultad de Medicina, U.A.S.L.P., San Luis Potosí, S.L.P., México;
Investigación y Estudios de Posgrado, Facultad de Ingeniería, U.A.S.L.P., San Luis Potosí, S.L.P.,
author for correspondence, e-mail: email@example.com, Fax: (52+444) 825 43 26)
(Received 6 May 2002; accepted 25 August 2003)
Abstract. The environmental impact of arsenic and heavy metals on a 105 km
area of the historical
and recent mining site of Villa de la Paz-Matehuala, San Luis Potosí (Mexico) was evaluated. Results
of soil samples reported concentrations between 19–17 384 mg kg
As, 15–7200 mg kg
3450 mg kg
Pb and 26–6270 mg kg
Zn, meanwhile, the concentrations in dry stream sediment
samples were found to vary between 29–28 600 mg kg
As, 50–2160 mg kg
Pb, 71–2190 mg
Cu, and 98–5940 mg kg
Zn. The maximum arsenic concentration in pluvial water storage
ponds (265 µgL
), near the main potential sources of pollution, exceed by 5 times the Mexican
drinking water quality guideline (50 µgL
). The arsenic concentrations in water storage ponds and
stream sediments decrease as distance from the potential sources increase. A special case is the ‘Cer-
rito Blanco’ area located 5 km east of Matehuala, where the highest arsenic concentration in water
was found (>5900 µgL
), exceeding by 100 times the established guideline, thus representing a
severe health risk. The results suggest that arsenic and heavy metal dispersion from their pollution
sources (historical and active tailings impoundments, waste rock dumps and historical slag piles), is
mainly associated in this site with: (1) ﬂuvial transportation of mine waste through streams that cross
the area in W–E direction; and (2) aeolian transportation of mineral particles in SW–NE direction.
Finally, control measures for pollution routes and remediation measures of the site are proposed.
Keywords: arsenic, environmental impact of mining, heavy metals, historical mining, semi-arid
climate, tailings impoundments
Mining is one of the most important sources of heavy metals in the environment.
Mining-milling operations and disposal of tailings (the ﬁnely ground remains of
milled ores) in addition to smelting and metal reﬁning provide signiﬁcant sources
of pollution. In 1988, Nriagu and Pacyna estimated that 635 × 10
and 35 × 10
arsenic had been released into the environment (atmosphere,
aquatic systems and soil) by the mining and metallurgy industry, which represented
35 and 22%, respectively, of the total Pb and As released into the environment.
Water, Air, and Soil Pollution 152: 129–152, 2004.
© 2004 Kluwer Academic Publishers. Printed in the Netherlands.