ars.els-cdn.com · web viewc laboratorio de electroquímica y análisis de superficies, facultad de...
TRANSCRIPT
Electronic supplementary material:
“Spatial Distribution, Mobility and Potential Health Risks of
Arsenic and Lead Concentrations in Semiarid Fine Top-Soils of
Durango City, Mexico”
Fabiola S. Sosa-Rodrígueza, Jorge Vazquez-Arenasb, Patricia Ponce Peñac, Miguel
A. Escobedo-Bretadoc, Francisco X. Castellanos-Juárezd, Israel Labastidae, René H.
Larac, *
a Research Area of Growth and Environment, Metropolitan Autonomous University,
Azcapotzalco (UAM-A), Av. San Pablo 180, Mexico City, 02200, México.
b Centro Mexicano para la Producción más Limpia, Instituto Politécnico Nacional (IPN),
Avenida Acueducto S/N, Col. La Laguna Ticomán, Ciudad de México, 07340, México.
c Laboratorio de Electroquímica y Análisis de Superficies, Facultad de Ciencias Químicas,
Departamento de Ciencia de Materiales, Universidad Juárez del Estado de Durango
(UJED), Av. Veterinaria S/N, Circuito Universitario, Col. Valle del Sur, 34120, Durango,
DGO, Mexico.
d Instituto de Investigaciones Científicas (IIC), Universidad Juárez del Estado de Durango,
Av. Universidad esq. Av. Fanny Anitua S/N, Zona Centro, 34000 Durango, DGO, Mexico.
e Department of Energy, Metropolitan Autonomous University, Azcapotzalco (UAM-A),
Av. San Pablo 180, Mexico City, 02200, México.
* Corresponding author: R.H. Lara ([email protected], [email protected])
Figure S1. Location of hard rock dumps, operating tailing impoundment and inactive tailing
impoundments. The information here was used during geostatistical analysis to evaluate deeply
geochemical correlations between As and Pb distribution and the potential pollution sources with
geostatistical analysis.
Figure S2. Images illustrating intermittent eolic waste dispersion in the Durango city and
the conurbation with The Cerro de Mercado mining unit. Intense and intermittent eolic
events are occurring mainly during spring and summer. Highest wind velocity is 61 km s-1.
Pluvial events are register typically during autumn. Images cover only a part side of the
city.
a. Spherical
b. Gaussian
Figure S3. Spherical and Gaussian interpolation model outputs.
Figure S4. Typical XRD pattern of surface (urban sprawl) soil samples collected in the study site
(i.e. sample 9). Mineralogical identification and corresponding patterns are depicted in the figure.
Table S1. Chemical and physical parameters obtained for collected soil samples in Durango city
(Mexico).
Sampling point
pH ORP(mV/SHE)
Conductivity
(mS cm-1)
TOC(% Wt)
MO(% Wt)
CEC(meq
100g-1)
Textural composition(% Wt)
Arcille Sand Lime9121834671021051101168756789869
Average
7.37.57.37.67.37.37.27.76.97.26.66.87.87.37.26
335328423456357346478501389278277456375390
384.5
4963311550154020201925247038
33.9
1.91.91.92.92.13.12.12.72.72.62.62.92.92.62.4
3.33.43.45.03.75.23.64.64.64.64.55.05.04.74.3
12.517.5171843
20.516.52014
17.516.512.513.512.518.3
12 68 20 20 60 20 58 34 8 20 54 26 16 74 10 16 68 16 23 53 24 38 50 12 10 68 22 26 62 12 40 40 20 42 26 32 40 28 32 40 28 32 27.8 50.9 20.4
Table S2. Semivariogram of the spatial correlation of the As and Pb concentrations.
Interpolation model Spherical GaussianRoot-Mean-Square 19.01339 22.28349Root-Mean-Square Standarized 0.9793022 1.134368Nugget 0 0.002775Partial Sill 378.055192 727.724510Range 728.783994 2,836.516536
Figure S5. Cyclic voltammograms (positive scans) for CPE-polluted soil sample (i.e. sampling
point 64) (a), CPE-without mineral species (100 % graphite) (b), CPE-arsenopyrite (c) and CPE-
galena (d) in NaCl 0.1 M at pH 7.3. scan rate= 20 mV s-1. Quiescent solution. Ambient conditions.
CPE= carbon paste electrode.
Figure S6. Complementary image illustrating location of hard rock dumps, operating tailing
impoundment and inactive tailing impoundments in the conurbated semiarid soils in Durango city.
Figure S7. Geochemical indexes (GI) for As concentration levels regarding soil backgrounds. GI
was calculated in typical form according to Wei and Yang (2010).
Table S3. Distribution of As and Pb concentration levels and the corresponding % of total
concentration in soil samples of the city of Durango (Mexico).
Sampling points As levels
(mg Kg-1)
Sampling points Pb levels
(mg Kg-1)
2, 4, 5, 8-13, 15, 16, 18, 19, 21-
23, 26-29, 32-41, 45-48, 50-101
4.37-21
(64 %)
8, 32, 34, 35, 37, 39, 41, 42, 50, 51, 66, 67, 69-
73, 76, 81, 83, 86, 88, 89, 95
8.3.-25.13
(20 %)
1, 3, 6, 7, 14, 18, 21, 24, 25, 30,
31, 42-44, 48, 49
21-41.6
(12 %)
4-6, 8, 10, 11, 14, 18, 19, 22, 24, 25, 28, 29, 30,
34, 37, 39, 41, 47, 48, 50, 53, 54, 56, 57, 69, 75,
76, 78-80, 85, 88, 91-95, 98, 99
25.13-38
(34 %)
102-106, 108, 111, 121, 122, 124,
125
41.6-85.5
(8 %)
1,2,6,14-16, 20, 22, 25, 26, 31, 43, 44, 57, 59,
82, 85, 96, 99, 102-105, 109, 112, 116, 117,
119, 121, 124, 125, 129-132
38-82
(28 %)
107, 109, 110, 112-120, 123, 126-
133
85.51-220.74
(16 %)
12, 19, 30, 45, 48, 54, 58, 60-64, 100, 101, 106,
108, 110, 112, 115, 118, 120, 122, 126, 133
82-132
(18 %)