Atlas of Contaminated Sites

Notable case, Torreón, Coahuila, Mexico

Torreón (Met-Mex Peñoles smelter)

Met-Mex Peñoles, Torreón

Met-Mex Peñoles, one of the world's largest complexes for smelting and refining silver, lead, zinc and cadmium, has worked in the middle of Torreón since 1901. Its dust contaminated soil and homes in nearby neighbourhoods, and children had high blood lead, traced to the smelter by isotope analysis.

Status
Remediation under way
Activity
since 1901
Media
soil, air
Kind of site
smelter
  1. Area. No official perimeter. The isotope study by Soto-Jiménez and Flegal (2011) sampled a 113 km² area around the plant; the highest lead deposition is within 1 km of the smelter.

Contaminants

Metals

Metalloids

Status

Remediation under way

The plant is operating. After environmental and public-health interventions by the authorities and the company, median blood lead in a group of children followed from 2001 fell from 10.12 to 4.4 µg/dl in five years (Rubio-Andrade et al. 2011). Measurements in 2015 and 2017 still find lead-rich particles in urban dust within 3 km of the complex (Soto-Jiménez et al. 2023, 2026).

Story

The Met-Mex Peñoles complex comprises a lead smelter, a lead-silver refinery and an electrolytic zinc refinery, with plants for sulphuric acid, cadmium and bismuth (Spanish Wikipedia). It stands inside the city, in an arid, dusty region; west and east of the stack the Sierra de las Noas hill hinders the dispersion of particles.

Published studies describe soil and dust with high lead, cadmium and arsenic in the neighbourhoods beside the plant. Across a 113 km² area, lead in soil ranged from 130 to 12,050 µg/g and in outdoor dust from 150 to 14,365 µg/g, against a background of 7.3–33.3 µg/g; the isotopic composition of lead in the blood of 34 children matched that of soil, dust and aerosols and that of the ores processed at the smelter (Soto-Jiménez and Flegal 2011).

After interventions by the authorities and the company, a follow-up study begun in 2001 on 232 children from nine neighbourhoods recorded a fall in blood lead in step with the fall of lead in soil. In 2014 a study of 512 adolescents still found spatial clusters of higher blood lead and urinary cadmium next to and downwind of the smelter, in the same areas identified more than a decade earlier (García-Vargas et al. 2014).

Timeline

  1. 1901The Torreón metallurgical complex starts operating.
  2. 2001Start of the follow-up study of blood lead in 232 children from nine neighbourhoods.
  3. 2011Isotope analysis attributes the lead in children's blood to the smelter.
  4. 2017Measurement campaigns of dry lead deposition in the city (2015 and 2017).

Health

In the 2001–2006 follow-up, median blood lead in 232 children was 10.12 µg/dl at the start (maximum 43.8) and 4.4 µg/dl after 60 months (Rubio-Andrade et al. 2011). In 34 children aged 2–17, mean blood lead was 11.0 ± 5.3 µg/dl (Soto-Jiménez and Flegal 2011). Among 512 adolescents aged 12–15, the higher blood lead values (3.6–14.7 µg/dl) and urinary cadmium clustered near and downwind of the smelter (García-Vargas et al. 2014).

Remediation

  1. —emission control and neighbourhood clean-upEnvironmental and public-health interventions by the authorities and the company in the neighbourhoods around the plant, with which the follow-up study associates the fall of lead in soil and blood (Rubio-Andrade et al. 2011). The sources consulted do not describe them in detail.

From the literature

Species that acted on one of this site's contaminants in at least one study. The list is automatic and takes no account of this site's soil, concentrations or climate.

Plants

Fungi

The rest are on the contaminant pages.

Sources

  1. Rubio-Andrade M. et al. Follow-up study on lead exposure in children living in a smelter community in northern Mexico. Environmental Health 10:66, BioMed Central, 2011
  2. Soto-Jiménez M.F., Flegal A.R. Childhood lead poisoning from the smelter in Torreón, México. Environmental Research, Elsevier, 2011
  3. García-Vargas G.G. et al. Spatial clustering of toxic trace elements in adolescents around the Torreón, Mexico lead-zinc smelter. Journal of Exposure Science & Environmental Epidemiology, Nature, 2014
  4. Soto-Jiménez M.F. et al. Atmospheric Dry and Lead Deposition in an Arid Mexican City: Legacy of Smelting and Leaded Gasoline. Archives of Environmental Contamination and Toxicology, Springer, 2026
  5. Soto-Jiménez M.F. et al. Environmental and health implications of Pb-bearing particles in settled urban dust from an arid city affected by Pb-Zn factory emissions. Scientific Reports, Nature, 2023
  6. Industrias Peñoles, Wikipedia (es), 2026

Draft compiled from public sources, not yet reviewed.