Sorbent-modified biodegradation studies of the biocidal cationic surfactant cetylpyridinium chloride.
Ecotoxicol Environ Saf
; 182: 109417, 2019 Oct 30.
Article
em En
| MEDLINE
| ID: mdl-31302333
ABSTRACT
Biodegradability studies for the cationic surfactant cetylpyridinium chloride (CPC) are hampered by inhibitory effects on inoculum at prescribed test concentrations (10-20â¯mgâ¯organic carbon/L). In this study, we used 14C labeled CPC in the 28â¯d Headspace Test (OECD 310) and demonstrated that CPC was readily biodegradable (10->60% mineralization within a 10 day window) at test concentrations 0.006-0.3â¯mg/L with CPC as single substrate. Biodegradation efficiency was comparable over this concentration range. CPC inhibited degradation at 1â¯mg/L and completely suppressed inoculum activity at 3â¯mg/L. In an extensive sorbent modified biodegradation study we evaluated the balance between CPC bioaccessibility and toxicity. A non-inhibitory concentration of 0.1â¯mg/L CPC was readily biodegradable with 83% sorbed to SiO2, while biodegradation was slower when 96% was sorbed. SiO2 mitigated inhibitory effects of 1â¯mg/L CPC, reaching >60% biodegradation within 28â¯d; inhibitory effects were also mitigated by addition of commercial clay powder (illite) but this was primarily reflected by a reduced lag phase. At 10â¯mg/L CPC SiO2 was still able to mitigate inhibitory effects, but bioaccessibility seemed limited as only 20% biodegradation was reached. Illite limited bioaccessibility more strongly and was not able to sustain biodegradation at 10â¯mg/L CPC.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Biodegradação Ambiental
/
Cetilpiridínio
/
Anti-Infecciosos Locais
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Revista:
Ecotoxicol Environ Saf
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Holanda