Geochemical transfer of cadmium in river sediments near a lead-zinc smelter.
Ecotoxicol Environ Saf
; 196: 110529, 2020 Jun 15.
Article
em En
| MEDLINE
| ID: mdl-32247240
ABSTRACT
Cadmium (Cd) is a highly toxic element and non-essential to human. Herein, the source and fate of Cd were examined in a typical sediment profile from the North River, South China, which was affected by the massive Pb-Zn smelting activities for decades. An exceptionally high enrichment of Cd, 107-441 mg/kg, was observed across the whole profile. Approximately 50-75% of Cd was retained in the weak acid soluble fraction. Risk assessment based on geoaccumulation index (Igeo), potential ecological risk index (Eri), bioavailable metal index (BMI) and toxic risk index (TRI) further indicated an extremely strong degree of potential ecological pollution and high toxic risks. The mineralogical composition of particles from the sediment profile exhibited the presence of pyrite, magnetite, wurtzite and greenockite. This further confirmed that Cd was migrated from smelting slags to the North River basin and enriched in sediment profile. Sediment Cd speciation analysis also implied a possible transformation of Cd from metal oxides in smelting slags to adsorbed phases and carbonates, which enhances the bioavailability of Cd. The findings indicate proper countermeasures or remediation approaches should be promptly taken towards high ecological risks of Cd arising from the depth profile extending nearly 1 m, due to lead-zinc smelting related activities.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes Químicos da Água
/
Zinco
/
Cádmio
/
Monitoramento Ambiental
/
Sedimentos Geológicos
/
Rios
/
Chumbo
Tipo de estudo:
Etiology_studies
/
Risk_factors_studies
Limite:
Humans
País/Região como assunto:
Asia
Idioma:
En
Revista:
Ecotoxicol Environ Saf
Ano de publicação:
2020
Tipo de documento:
Article