Derivation of ecological criteria for copper in land-applied biosolids and biosolid-amended agricultural soils.
The difference in availability between soil metals added via biosolids and soluble salts was not taken into account in deriving the current land-applied biosolids standards. In the present study, a biosolids availability factor (BAF) approach was adopted to investigate the ecological thresholds for copper (Cu) in land-applied biosolids and biosolid-amended agricultural soils. First, the soil property-specific values of HC5add(the added hazardous concentration for 5% of species) for Cu2+salt amended were collected with due attention to data for organisms and soils relevant to China. Second, a BAF representing the difference in availability between soil Cu added via biosolids and soluble salts was estimated based on long-term biosolid-amended soils, including soils from China. Third, biosolids Cu HC5inputvalues (the input hazardous concentration for 5% of species of Cu from biosolids to soil) as a function of soil properties were derived using the BAF approach. The average potential availability of Cu in agricultural soils amended with biosolids accounted for 53% of that for the same soils spiked with same amount of soluble Cu salts and with a similar aging time. The cation exchange capacity was the main factor affecting the biosolids Cu HC5inputvalues, while soil pH and organic carbon only explained 24.2 and 1.5% of the variation, respectively. The biosolids Cu HC5inputvalues can be accurately predicted by regression models developed based on 2-3 soil properties with coefficients of determination (R2) of 0.889 and 0.945. Compared with model predicted biosolids Cu HC5inputvalues, current standards (GB4284-84) are most likely to be less protective in acidic and neutral soil, but conservative in alkaline non-calcareous soil. Recommendations on ecological criteria for Cu in land-applied biosolids and biosolid-amended agriculture soils may be helpful to fill the gaps existing between science and regulations, and can be useful for Cu risk assessments in soils amended with biosolids.
School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China; Health Environment Sustainable Development Asia, International Copper Association, Shanghai 200020, China.
Tao
T
Lu
Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Jumei
J
Li
Department of Environmental Engineering and Chemistry, Luoyang Institute of Science and Technology, Luoyang 471023, Henan Province, China.
Xiaoqing
X
Wang
School of Resources and Environment, University of Jinan, Jinan 250022, Shandong Province, China. Electronic address: ybma@caas.ac.cn.
Yibing
Y
Ma
Division Soil and Water Management, Katholieke Universiteit Leuven, 3001 Leuven, Belgium.
Erik
E
Smolders
School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China.
Nanwen
N
Zhu
D000383:Agriculture / Q000379:methods / Q000592:standards; D002681:China; D003300:Copper / Q000032:analysis* / Q000494:pharmacology; D004463:Ecology / Q000379:methods / Q000592:standards; D006863:Hydrogen-Ion Concentration; D012044:Regression Analysis; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000493:pharmacokinetics; D014866:Waste Products / Q000032:analysis*
D012987:Soil; D012989:Soil Pollutants; D014866:Waste Products; D003300:Copper
Availability; Biosolids; China; Copper; Ecological criteria