Key role of persistent free radicals in soil for persulfate activation: impacts on benzo[]pyrene degradation.

Environmentally persistent free radicals (EPFRs) have been widely detected in polycyclic aromatic hydrocarbon (PAH)-contaminated soils, but the activation of persulfate by inherent EPFRs in PAH-contaminated soil for the transformation of PAHs remains unclear. In the present study, benzo[]pyrene (B[]P) was selected as a representative PAH and its transformation in a persulfate/B[]P-contaminated soil system was studied without the addition of any other activator. Results indicated that EPFRs in the soil activated persulfate to produce reactive oxygen species (ROS) and degraded B[]P.

Prevalence and Risk Factors for COPD in an Urbanizing Rural Area in Western China: A Cross-Sectional Study.

Purpose: To investigate the prevalence and risk factors for chronic obstructive pulmonary disease (COPD) in a rural area in western China with severe air pollution.

Patients And Methods: 10% of local residents aged 40 years and above were included using a convenience sampling method. This was a cross-sectional study.