Acute inhalation toxicity of ammonia: revisiting the importance of RD50 and LCT01/50 relationships for setting emergency response guideline values.
Regul Toxicol Pharmacol
; 66(3): 315-25, 2013 Aug.
Article
en En
| MEDLINE
| ID: mdl-23707397
ABSTRACT
This study examined the acute median lethal concentration (LC(50)) and the non-lethal threshold concentration (LC(01)) of ammonia in male and female Wistar rats nose-only exposed at exposure durations of either 1 or 4 h. Additional attributes characterizing the acute toxicity of inhaled ammonia were determined during a post-exposure period of 2 weeks. The objective of this study is to further refine the methodology applied to derive Emergency Response Planning Guideline (ERPG) values on potent sensory irritants in a controlled rat bioassay. In the more susceptible male rats the 1- and 4-h LC(50) (LC(01)) were 12,303 (10,067) and 4923 (4028) mg/m(3), respectively. At sublethal exposure levels the ventilation of rats was about one third of normal breathing. This change in ventilation and inhalation dosimetry was adjusted for Cxt-dependent lethal endpoints whereas sensory irritation-related phenomena were C-dependently adjusted. In summary, the outcome of this study shows that C- and C × t-dependent causes of toxicity need to be appreciated when extrapolating across species with species-specific inhalation dosimetry. It also appears to be indispensable that each exposure metric must be disentangled when translating C × t-dependent lethality and reflexively-induced, sensation-based C-dependent point of departures. For one hour exposure periods, these PODs were derived to be 1500 and 500 ppm, respectively.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
2_ODS3
Problema de salud:
2_quimicos_contaminacion
Asunto principal:
Guías como Asunto
/
Exposición por Inhalación
/
Pruebas de Toxicidad Aguda
/
Contaminantes Atmosféricos
/
Amoníaco
Tipo de estudio:
Guideline
Límite:
Animals
Idioma:
En
Revista:
Regul Toxicol Pharmacol
Año:
2013
Tipo del documento:
Article
País de afiliación:
Alemania