Temporal and spatial variation, input fluxes and risk assessment of cyclic methylsiloxanes in Rivers-Bohai Sea System.
Ecotoxicol Environ Saf
; 231: 113169, 2022 Feb.
Article
en En
| MEDLINE
| ID: mdl-35032727
ABSTRACT
In the present study, the total concentrations of three cyclic methylsiloxanes (ΣCMSs), including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6), in surface water and sediment samples of five main rivers draining into the Bohai Sea were in the range of 1.62-1.39 × 103 ng/L and 1.92-1.69 × 103 ng/g dw, respectively. Riverine input had great influence on the coastal distribution of siloxanes in the Bohai Sea. The concentrations of ΣCMSs in coastal sediments farthest away (40-50 Km) from the estuaries were only 4-33% of those close to the estuaries. But surprisingly, compared with those in coastal sediments (1.03-1.44 × 103 ng/g dw), the concentrations of CMSs (1.56-2.67 × 103 ng/g dw) in some deep-sea sediments were higher, and certain positive correlation existed between sediment ΣCMSs in this area with the total petroleum hydrocarbons concentration (R2 = 0.92, p < 0.05) suggested offshore oil exploitation as one important emission source of siloxanes. Overall, calculated based on their sediment concentrations, D4-D6 had negligible ecological risks to the benthic organisms in river-Bohai Sea system, i.e. HQs < 1. However, sediment-accumulation of siloxanes should be paid attention, especially for some deep-sea sediments nearby drilling platforms, where it will take only less than 1 year for D4 to reach its threshold.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Contaminantes Químicos del Agua
/
Petróleo
Tipo de estudio:
Etiology_studies
/
Risk_factors_studies
País/Región como asunto:
Asia
Idioma:
En
Revista:
Ecotoxicol Environ Saf
Año:
2022
Tipo del documento:
Article
País de afiliación:
China