Trace element and Sigma DDT concentrations in horticultural soils from the Tasman, Waikato and Auckland regions of New Zealand.
The long-term routine use of agrichemicals can result in elevated levels of trace elements and persistent organic pollutants in soils. Trace element concentrations and SigmaDDT levels were measured in soil (0-7.5 cm) samples collected from horticultural and grazing properties in 3 regions of New Zealand (Auckland, Tasman and Waikato). Elevated levels of arsenic (<2 to 58 mg kg(-1)), cadmium (<0.1 to 1.5 mg kg(-1)), copper (5 to 523 mg kg(-1)), lead (5 to 243 mg kg(-1)) and SigmaDDT (<0.03 to 34.5 mg kg(-1)) were detected in soils from all 3 regions. With the exception of cadmium and zinc, significantly higher levels of contaminants were generally detected in horticultural soils than in grazing soils. Our results have implications for the on-going use of agrichemicals as concentrations of cadmium, copper, tin and zinc in some samples exceeded ecotoxicity based soil criteria. The p,p'-DDE:DDT ratios indicate that the degradation of DDT in NZ horticultural soils may be inhibited by the co-contamination with trace elements.
Gaw
S K
SK
University of Waikato, Private Bag 3105, Hamilton, New Zealand. skg3@waikato.ac.nz
Wilkins
A L
AL
Kim
N D
ND
Palmer
G T
GT
Robinson
P
P
D000383:Agriculture; D001151:Arsenic / Q000032:analysis*; D003634:DDT / Q000032:analysis*; D004784:Environmental Monitoring; D019216:Metals, Heavy / Q000032:analysis*; D009520:New Zealand; D010573:Pesticide Residues / Q000032:analysis*; D010575:Pesticides / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis*; D014026:Nicotiana
D019216:Metals, Heavy; D010573:Pesticide Residues; D010575:Pesticides; D012989:Soil Pollutants; D003634:DDT; D001151:Arsenic