Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 28, 2007
Publication Date: November 7, 2007
Citation: Codling, E.E., Chaney, R.L., Green, C.E. 2007. Lead and Arsenic Uptake by Carrots Grown on Five Orchard Soils With History of Lead Arsenate Used. Meeting Abstract. p. 241. Technical Abstract: Lead arsenate was used to control codling moth in apple and plum orchards from 1900 to 1960. Consequently, many orchard soils are contaminated with lead (Pb) and arsenic (As). Some of these lands are being used for urban development and vegetable crop production. Both soil Pb and As have become important environmental concerns, due to their potential carcinogenic and neurological properties. The objective of this study was to determine the uptake of As and Pb by carrots grown on lead arsenate contaminated soils. Five orchard soils (Bagstown, Hudson, Spike, Burch, and Chashmont) with total Pb concentrations ranging from 350 to 1159 mg kg-1 and As ranging from 43 to 290 mg kg-1 were planted with three carrot cultivars (Gold king, Monique and Denver-26). A soil with no history of lead arsenate application (Christiana) was used as control. Soils were mixed with lime and fertilizer to achieve a pH of 6.5. Four kilograms of each soil were placed into a 20 cm diameter plastic pot and planted with fifteen carrot seeds. Pots were placed in a growth chamber in a randomized complete block design with 16 hours of light at 25oC and 8 hours of dark at 19oC. All treatments were replicated four times. Plants were thinned to 5 per pot and grown for 90 days. At harvest, carrots ware washed, peeled and freeze-dried. Carrot As and Pb concentrations were determined using a microwave for digestion and an ICP-MS. The highest yield (25 g) was in the plants grown on the Bagstown soil. Lead and arsenic concentrations increased in plants grown on the orchard soils compared to the control. Arsenic concentrations were higher in the peel than the root, while Pb concentrations were higher in the roots. When peeled, the elevated levels of As and Pb in the carrot grown on these soils could be a potential health concern. However, further studies are needed to determine bioaccessibility of As and Pb in carrots grown on lead arsenate orchard soil.