Soil lead (Pb) and urban grown lettuce: Sources, processes, and implications for gardener best management practices

Sara Perl Egendorf; Henry M Spliethoff; Hannah A Shayler; Jonathan Russell-Anelli; Zhongqi Cheng; Anna Heming Minsky; Thomas King; Murray B McBride

doi:10.1016/j.jenvman.2021.112211

Soil lead (Pb) and urban grown lettuce: Sources, processes, and implications for gardener best management practices

J Environ Manage. 2021 May 15:286:112211. doi: 10.1016/j.jenvman.2021.112211. Epub 2021 Mar 2.

Authors

Sara Perl Egendorf¹, Henry M Spliethoff², Hannah A Shayler³, Jonathan Russell-Anelli³, Zhongqi Cheng⁴, Anna Heming Minsky⁵, Thomas King⁶, Murray B McBride³

Affiliations

¹ Brooklyn College of the City University of New York, Department of Earth and Environmental Sciences, 2900 Bedford Ave, Brooklyn, NY, 11210, USA; The Graduate Center of the City University of New York, Department of Earth and Environmental Sciences, 365 5th Ave, New York, 10016, USA; The Advanced Science Research Center at the Graduate Center of the City University of New York, Environmental Sciences Initiative, 85 St. Nicholas Terrace, New York, 10031, USA. Electronic address: spe34@cornell.edu.
² Center for Environmental Health, New York State Department of Health, Corning Tower Room 1743, Empire State Plaza, Albany, NY, 12237, USA.
³ Cornell University, School of Integrative Plant Science, Soil and Crop Sciences Section, 233 Emerson Hall, Ithaca, NY, 14853, USA.
⁴ Brooklyn College of the City University of New York, Department of Earth and Environmental Sciences, 2900 Bedford Ave, Brooklyn, NY, 11210, USA; The Graduate Center of the City University of New York, Department of Earth and Environmental Sciences, 365 5th Ave, New York, 10016, USA.
⁵ Brooklyn College of the City University of New York, Department of Earth and Environmental Sciences, 2900 Bedford Ave, Brooklyn, NY, 11210, USA.
⁶ New York State Department of Agriculture and Markets, 6 Harriman Campus Road, Albany, NY, 11206, USA.

PMID: 33667819
DOI: 10.1016/j.jenvman.2021.112211

Abstract

Urban community gardeners employ a range of best practices that limit crop contamination by toxicants like lead (Pb). While Pb root uptake is generally low, the relative significance of various Pb deposition processes and the effectiveness of best practices in reducing these processes have not been sufficiently characterized. This study compared leafy lettuce (Lactuca sativa) grown in high Pb (1150 mg/kg) and low Pb (90 mg/kg) soils, under three different soil cover conditions: 1) bare soil, 2) mulch cover to limit splash, and 3) mulch cover under hoophouses to limit splash and air deposition, in a New York City (NYC) community garden and a rural site in Ithaca, New York (NY). The lettuces were further compared to greenhouse (Ithaca) and supermarket (NYC) samples. Atmospheric deposition was monitored by passive trap collection through funnel samplers. Results show that in low Pb soils, splash and atmospheric deposition accounted for 84 and 78% of lettuce Pb in NYC and Ithaca, respectively. In high Pb soils, splash and atmospheric deposition accounted for 88 and 93% of Pb on lettuces, with splash being the dominant mechanism. Soil covers were shown to be effective at significantly (p < 0.05) reducing lettuce Pb contamination, and mulching is strongly recommended as a best practice.

Keywords: Atmospheric deposition; Contaminant mitigation; Crop contamination; Soil Pb; Urban gardening.

MeSH terms

Lactuca
Lead
New York City
Soil Pollutants* / analysis
Soil*

Substances

Soil
Soil Pollutants
Lead