Prediction of the environmental fate and aquatic ecological impact of nitrobenzene in the Songhua River using the modified AQUATOX model

An accidental discharge of nitrobenzene happened in November 2005 in the Songhua River,China.The AQUATOX model was modified and adapted to simulate the time-dependent nitrobenzene distribution in this multimedia aquatic system and its potential ecological impacts.Nitrobenzene concentrations in flowing water,sediment,and biota were predicted.Based on the initial concentrations of nitrobenzene observed in the field during the accidental discharge,that is,0.167-1.47 mg/L at different river segments, the predic...

Occurrence,formation and environmental fate of polycyclic aromatic hydrocarbons in biochars

Biochar application for soil and agro-environmental development has attracted great attention due to its numerous advantages:improving the soil,mitigating greenhouse gas emissions,increasing crop productivity,and augmenting soil carbon storage.However,during the pyrolytic conversion of waste biomass,polycyclic aromatic hydrocarbons(PAHs),a category of toxic organic pollutants,are inescapably generated and linger on the residual solid coproduct called biochar.Therefore,it is crucial to assess the environmental persistence,bioavailability,effects of biochar-borne PAHs on plant growth and soil microbial community dynamics,food safety,and human health after application into soils.This review highlights the basic need to unravel critical mechanisms driving PAH formation in biochar and the dynamics between the sorbent(biochar)and soil microbes,along with the possible mitigation strategies.Current research gaps,including the influence of biochar application on the short and long-term fate of PAHs,as well as the proper control measures for biochar quality and associated risks,will be discussed herein.The key research findings from this script will lead to proposals in technological and quality control measures during biochar production to ensure they are clean and safe.

Fate of tetracyclines in swine manure of three selected swine farms in China

Veterinary antibiotics can enter the environment due to the common practice of land application of manure from treated animals.The environmental fate of tetracyclines in swine manure after composting and field application remains largely unknown.This study analyzed the concentrations of tetracyclines in manure,manure-based compost and compost amended soil in selected swine farms from Beijing,Jiaxing and Putian,China to determine the dilution effects of antibiotics when released into the soil environment.The results demonstrate that residues of antibiotics were detected in all samples and chlortetracycline as well as its degradation products should be regarded critically concerning their potential ecotoxicity.Application of manure-based compost to soil could reduce the possible risk posed by antibiotic contamination,but the trigger value of 100 μg/kg was still exceeded in soil samples （776.1 μg/kg dw） from Putian City after application of compost.Field studies such as the present one can help to improve the routine administration of antibiotic-containing composted manure.