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This paper describes the fate of a nitrobenzene-degrading bacterium, Klebsiella oxytoca NBA-1, which was isolated from a pharmaceutical wastewater treatment facility. The 90-day survivability of strain NBA-1 after exposure to sludge under anaerobic and aerobic conditions was investigated. The bacterium was inoculated into sludge amended with glucose and p -chloronitrobenzene ( p -CNB) to compare the bacterial community variations between the modified sludge and nitrobenzene amendment. The results showed that glucose had no obvious effect on nitrobenzene biodegradation in the co-metabolism process, regardless of the presence/absence of oxygen. When p -CNB was added under anaerobic conditions, the biodegradation rate of nitrobenzene remained unchanged although p -CNB inhibited the production of aniline. The diversity of the microbial community increased and NBA-1 continued to be one of the dominant strains. Under aerobic conditions, the degradation rate of both nitrobenzene and p -CNB was only 20% of that under anaerobic conditions. p -CNB had a toxic effect on the microorganisms in the sludge so that most of the DGGE (denaturing gradient gel electrophoresis) bands, including that of NBA-1, began to disappear under aerobic conditions after 90 days of exposure. These data show that the bacterial community was stable under anaerobic conditions and the microorganisms, including NBA-1, were more resistant to the adverse environment. [ABSTRACT FROM AUTHOR]

Increasing evidence indicates the adverse effect of air pollution exposure during pregnancy on neurologic development among children. However, the impact on neurobehavioral development in fetus remains unknown. In 2017, a total of 1193 mother–newborns pairs were enrolled in a birth cohort study in Changsha, China. Exposures to PM 2.5 , PM 10, SO 2 , CO and NO 2 were determined by using inverse distance weighted method based on local monitoring station data. Neurobehavioral measure was administered at 48–72 h postpartum by utilizing the neonatal behavioral neurological assessment (NBNA). Basic information and covariates were collected by face to face interview. Generalized linear regression and multivariable restricted cubic spline function were performed to explore the trimester-specific association and dose-response relationship of maternal air pollution exposure with NBNA score, respectively. In adjusted three-pollutant model, PM 2.5 exposure in trimester 2 was negatively associated with behavior score (β, −0.003; 95% CI, −0.006, −0.001) and the inverse relation was more pronounced in male infants. In addition, PM 2.5 level in the 2nd trimester was negatively related to activetone score (β, −0.012; 95% CI, −0.021, −0.002) in a dose-dependent manner for both genders. Collectively, our results demonstrated that prenatal exposure to PM 2.5 was linked to poor neurobehavioral performance of newborns. The second trimester was the most sensitive time window for the developments of behavior and activetone, and male subject was more vulnerable as compared to females. • Prenatal exposure to PM 2.5 was associated with poor neurobehavioral performance of newborns. • The second trimester was the most sensitive time window for behavioral and activetone development. • Male newborns were more vulnerable to the influence of PM 2.5 as compared to females. [ABSTRACT FROM AUTHOR]