RESUMEN
Rate coefficients for the gas-phase reactions of OH radicals and Cl atoms with 1-methoxy-2-propanone (1-M-2-PONE), 1-methoxy-2-propanol (1-M-2-POL), and 1-methoxy-2-butanol (1-M-2-BOL) were determined at room temperature and atmospheric pressure using a conventional relative-rate technique. The following absolute rate coefficients were derived: k 1(OH + 1-M-2-PONE) = (0.64 ± 0.13) × 10-11, k 2(OH + 1-M-2-BOL) = (2.19 ± 0.23) × 10-11, k 3(Cl + 1-M-2-PONE = (1.07 ± 0.24) × 10-10, k 4(Cl + 1-M-2-POL) = (2.28 ± 0.21) × 10-10, and k 5 (Cl + 1-M-2-BOL) = (2.79 ± 0.23) × 10-10, in units of cm3 molecule-1 s-1. This is the first experimental determination of k 2-k 5. These rate coefficients were used to discuss the influence of the structure on the reactivity of the studied polyfunctional organic compounds. The atmospheric implications for 1-M-2-PONE, 1-M-2-POL, and 1-M-2-BOL and their reactions were investigated estimating atmospheric parameters such as lifetimes, global warming potentials, and average photochemical ozone production. The approximate nature of these values was stressed considering that the studied oxygenated volatile organic compounds are short-lived compounds for which the calculated parameters may vary depending on chemical composition, location, and season at the emission points.
Asunto(s)
Atmósfera/química , Cloro/química , Éteres/química , Radical Hidroxilo/química , Calentamiento Global , Cinética , Ozono , Compuestos Orgánicos Volátiles/químicaRESUMEN
We investigated the reproductive damage and teratogenic effect of an ethylene glycol-methyl cellosolve mixture on gestating Wistar rats, which received a daily intraperitoneal dose of different concentration of the mixture on day 8 of gestation until day 20. In rats treated with the mixture the number of live fetuses decreased and reabsorptions increased with increasing concentrations of the mixture, as well as the number of abnormal fetuses. We conclude that the ethylene glycol-methyl cellosolve mixture possesses a higher teratogenic potential than each of its constituents separately, producing reproductive damage, external fetal abnormalities, growth delay, and increased fetal death.
Se investigó el daño reproductivo y efecto teratogénico de una mezcla de etilenglicol y metilcelosolve en ratas gestantes, las cuales recibieron por vía intraperitoneal una dosis diaria, a diferentes concentraciones de la mezcla, del día 8 al día 20 de gestación. En las ratas tratadas con la mezcla el número de fetos vivos disminuyó y las reabsorciones y el número de fetos anormales aumentaron a mayor concentración de los solventes. Concluimos que la mezcla de etilenglicol-metilcelosolve tiene mayor efecto teratogénico que cuando actúan cada uno de los solventes por separado, produciendo daño reproductivo, anormalidades fetales externas, retraso del crecimiento y aumento de muerte fetal.
Asunto(s)
Animales , Femenino , Embarazo , Ratas , Feto , Glicoles de Etileno/toxicidad , Glicol de Etileno/toxicidad , Ratas Wistar , Reproducción , Teratógenos/toxicidadRESUMEN
We investigated the teratogenic effect of an ethylene glycol-methyl cellosolve mixture on gestating Wistar rats, that received a daily intraperitoneal dose of different concentration of the mixture on day 8 of gestation until day 20. Multivariate analysis and Post-Hoc Bonferroni tests were used and relative risk and attributable fraction were calculated. In rats treated with the mixture the number of live fetuses decreased and reabsorptions increased with increasing concentrations of the mixture, as well as the number of abnormal fetuses. Abnormalities consisted mainly in atypical craniofacial morphology, protruding tongue, edema, signs of growth delay and shorter limbs, their frequency and severity increased at higher concentrations of the mixture. We conclude that the ethylene glycol-methyl cellosolve mixture possesses a higher teratogenic potential than each of its constituents separately, producing external fetal abnormalities, growth delay, and increased fetal death.
Se investigó el efecto teratogénicos de una mezcla de etilenglicol y metilcelosolve en ratas gestantes, las cuales recibieron por vía intraperitoneal una dosis diaria, a diferentes concentraciones de la mezcla, del día 8 al día 20 de gestación. Se utilizaron las pruebas de análisis multivariado y Post-Hoc de Bonferroni, y se calcularon el riesgo relativo y la fracción atribuible. En las ratas tratadas con la mezcla el número de fetos vivos disminuyó y las reabsorciones y el número de fetos anormales aumentaron a mayor concentración de los solventes. Las anormalidades fetales consistieron principalmente en morfología atípica craneofacial, protrusión de la lengua, edema, signos de retraso de crecimiento y acortamiento de extremidades, y su frecuencia y severidad se incrementó a mayor concentración de la mezcla. Concluimos que la mezcla de etilenglicol-metilcelosolve tiene mayor efecto teratogénico que cuando actúan cada uno de los solventes por separado, produciendo anormalidades fetales externas, retraso del crecimiento y aumento de muerte fetal.