title: Environmental contextualisation of potential toxic elements and polycyclic aromatic hydrocarbons in biochar.
abstract: Nine dissimilar biochars, produced from varying feedstock at different pyrolysis temperatures, are appraised with respect to concentrations of potentially toxic elements, specifically, metals, metalloids and polycyclic aromatic hydrocarbons (PAHs). Concentrations of the metals and metalloids varied with the following ranges (mg kg(-1)): 0.02-0.94, Cd; 0.12-6.48, Cr; 0.04-13.2, Cu; 0.1-1.37, Ni; 0.06-3.87, Pb; 0.94-207, Zn and 0.03-0.27, As. Σ(16)PAH concentrations (16 Environmental Protection Agency (EPA) PAHs) range between 0.08 mg kg(-1) to 8.7 mg kg(-1). Subsequent comparison with background soil concentrations, concentration applied to the regulation of composted materials (Publicly Available Specification (PAS 100)) and European Union (EU) regulations relating to the application of sewage sludge to agricultural land suggest low risk associated with the concentrations of PTEs observed in biochar. Collectively, results suggest that environmental impacts attributable to metals, metalloids and PAHs associated with biochar following its application to soil are likely to be minimal.
authors.affiliation: School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
authors.forename: Alessia
authors.initials: A
authors.lastname: Freddo
authors.forename: Chao
authors.initials: C
authors.lastname: Cai
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Reid
mesh_terms: D000383:Agriculture; D002606:Charcoal; D004785:Environmental Pollutants / Q000032:analysis* / Q000633:toxicity; D017745:Incineration / Q000379:methods; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000633:toxicity; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods
chemical_list: D004785:Environmental Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D012722:Sewage; C540010:biochar; D002606:Charcoal