Estimated lead (Pb) exposures for a population of urban community gardeners
- 983 Downloads
Urban community gardens provide affordable, locally grown, healthy foods and many other benefits. However, urban garden soils can contain lead (Pb) that may pose risks to human health. To help evaluate these risks, we measured Pb concentrations in soil, vegetables, and chicken eggs from New York City community gardens, and we asked gardeners about vegetable consumption and time spent in the garden. We then estimated Pb intakes deterministically and probabilistically for adult gardeners, children who spend time in the garden, and adult (non-gardener) household members. Most central tendency Pb intakes were below provisional total tolerable intake (PTTI) levels. High contact intakes generally exceeded PTTIs. Probabilistic estimates showed approximately 40 % of children and 10 % of gardeners exceeding PTTIs. Children’s exposure came primarily from dust ingestion and exposure to higher Pb soil between beds. Gardeners’ Pb intakes were comparable to children’s (in µg/day) but were dominated by vegetable consumption. Adult household members ate less garden-grown produce than gardeners and had the lowest Pb intakes. Our results suggest that healthy gardening practices to reduce Pb exposure in urban community gardens should focus on encouraging cultivation of lower Pb vegetables (i.e., fruits) for adult gardeners and on covering higher Pb non-bed soils accessible to young children. However, the common practice of replacement of root-zone bed soil with clean soil (e.g., in raised beds) has many benefits and should also continue to be encouraged.
KeywordsUrban agriculture Community garden Urban soil Lead (Pb) exposure
Funding for this research was provided by the National Institute of Environmental Health Sciences, Award Number R21ES017921. The content is solely the responsibility of the authors and does not necessarily represent the official views of NIEHS or the National Institutes of Health. We greatly appreciate the contributions of Megan Gregory, other Healthy Soils, Healthy Communities collaborators, and NYC community gardeners.
- Ameroso, L. M., & Mazza, C. P. (2013). Children, gardens, and lead. Gardening Resources, Cornell University, June 14, 2013. http://www.gardening.cornell.edu/factsheets/misc/cgandlead.html. Accessed 18 July 2014.
- Aschengrau, A., Beiser, A., Bellinger, D., Copenhafer, D., & Weitzman, M. (1994). The impact of soil lead abatement on urban children’s blood lead levels: Phase II results from the boston lead-in-soil demonstration project. Environmental Research, 67(2), 125–148. doi: 10.1006/enrs.1994.1069.CrossRefGoogle Scholar
- ATSDR. (2007). Toxicological profile for lead. Atlanta, GA: Agency for Toxic Substances and Disease Registry, Public Health Service, US Department of Health and Human Services.Google Scholar
- Bassuk, N. L. (1986). Reducing lead uptake in lettuce. HortScience, 21(4), 993–995.Google Scholar
- Beam, A., Garber, L., Sakugawa, J., & Kopral, C. (2013). Salmonella awareness and related management practices in U.S. urban backyard chicken flocks. Preventive Veterinary Medicine. doi: 10.1016/j.prevetmed.2012.12.004.
- Beccaloni, E., Vanni, F., Beccaloni, M., & Carere, M. (2013). Concentrations of arsenic, cadmium, lead and zinc in homegrown vegetables and fruits: Estimated intake by population in an industrialized area of Sardinia, Italy. Microchemical Journal, 107, 190–195. doi: 10.1016/j.microc.2012.06.012.CrossRefGoogle Scholar
- CDC. (2012). CDC response to advisory committee on childhood lead poisoning prevention recommendations in “Low Level Lead Exposure Harms Children: A Renewed Call of Primary Prevention.” US Department of Health and Human Services, CDC. http://www.cdc.gov/nceh/lead/acclpp/cdc_response_lead_exposure_recs.pdf. Accessed 25 January 2013.
- Chaney, R. L., & Mielke, H. W. (1986). Standards for soil lead limitations in the United States. Trace Substances in Environmental Health, 20, 357–377.Google Scholar
- Chaney, R. L., Sterrett, S. B., & Mielke, H. W. (1984). The potential for heavy metal exposure from urban gardens and soils. In Proceedings of the symposium on heavy metals in urban gardens. Agricultural Experiment Station, University of the District of Columbia, Washington (pp. 37–84). http://www.indytilth.org/Links/Chaney_Exposure.pdf. Accessed 24 July 2013.
- Connecticut Department of Health. (2014). What you need to know about growing and eating fruits and vegetables safely. Connecticut Department of Health. http://www.ct.gov/dph/lib/dph/environmental_health/eoha/pdf/safe_gardening_fact_sheet_2014rev.pdf. Accessed 17 March 2015.
- Dalenberg, J. W., & van Driel, W. (1990). Contribution of atmospheric deposition to heavy-metal concentrations in field crops. Netherlands Journal of Agricultural Science, 38(3A), 369–379.Google Scholar
- Gittleman, M., Librizzi, L., & Stone, E. (2010). Community garden survey New York City results 2009/2010. GrowNYC. http://www.greenthumbnyc.org/pdf/GrowNYC_community_garden_report.pdf. Accessed 25 January 2013.
- Maisonet, M., Bove, F. J., & Kaye, W. E. (1997). A case–control study to determine risk factors for elevated blood lead levels in children, Idaho. Toxicology and Industrial Health, 13(1), 67–72.Google Scholar
- McBride, M. B. (2013). Arsenic and lead uptake by vegetable crops grown on historically contaminated orchard soils. Applied and Environmental Soil Science (ID 283742). doi: 10.1155/2013/283472.
- McBride, M. B., Shayler, H. A., Spliethoff, H. M., Mitchell, R. G., Marquez-Bravo, L. G., Ferenz, G. S., et al. (2014). Concentrations of lead, cadmium and barium in urban garden-grown vegetables: The impact of soil variables. Environmental Pollution, 194, 254–261. doi: 10.1016/j.envpol.2014.07.036.CrossRefGoogle Scholar
- Mitchell, R. G., Spliethoff, H. M., Ribaudo, L. N., Lopp, D. M., Shayler, H. A., Marquez-Bravo, L. G., et al. (2014). Lead (Pb) and other metals in New York City community garden soils: Factors influencing contaminant distributions. Environmental Pollution, 187, 162–169. doi: 10.1016/j.envpol.2014.01.007.CrossRefGoogle Scholar
- National Toxicology Program. (2012). NTP monograph: Health effects of low-level lead. NTP Monograph, 1, i–148.Google Scholar
- NGA. (2014). Garden to table: A 5-year look at food gardening in America. South Burlington, VT: National Gardening Association. http://www.hagstromreport.com/assets/2014/2014_0402_NGA-Garden-to-Table.pdf.
- NYSDEC, & NYSDOH. (2006). New York State brownfield cleanup program development of soil cleanup objectives technical support document. Appendix D. New York State Department of Environmental Conservation and New York State Department of Health. http://www.dec.ny.gov/docs/remediation_hudson_pdf/appendixde.pdf. Accessed 15 April 2013.
- Pinto, E., Almeida, A. A., & Ferreira, I. M. P. L. V. O. (2015). Assessment of metal(loid)s phytoavailability in intensive agricultural soils by the application of single extractions to rhizosphere soil. Ecotoxicology and Environmental Safety, 113, 418–424. doi: 10.1016/j.ecoenv.2014.12.026.CrossRefGoogle Scholar
- Spliethoff, H. M., Mitchell, R. G., Marquez-Bravo, L. G., Shayler, H. A., & McBride, M. B. (2014a). Homegrown produce consumption among urban community gardeners and household members. Presented at the 24th annual meeting of the International Society of Exposure Science, Cincinnati, OH.Google Scholar
- Spliethoff, H. M., Mitchell, R. G., Ribaudo, L. N., Taylor, O., Shayler, H. A., & Greene, V. (2014b). Lead in New York City community garden chicken eggs: Influential factors and health implications. Environmental Geochemistry and Health, 36(4), 633–649. doi: 10.1007/s10653-013-9586-z.CrossRefGoogle Scholar
- Stilwell, D. E., Rathier, T. M., Musante, C. L., & Ranciato, J. F. (2008). Lead and other heavy metals in community garden soils in Connecticut (No. Bulletin 1019). The Connecticut Agricultural Experiment Station. http://www.ct.gov/caes/lib/caes/documents/publications/bulletins/b1019.pdf.
- US EPA. (1989). Risk assessment guidance for superfund volume I human health evaluation manual (part A) (No. EPA/540/1-89/002). Washington, DC 20450: Office of Emergency and Remedial Response U.S. Environmental Protection Agency.Google Scholar
- US EPA. (2004). Risk assessment guidance for superfund volume 1: Human health evaluation manual (part E, supplemental guidance for dermal risk assessment). Washington, DC: Office of Emergency and Remedial Response.Google Scholar
- US EPA. (2010). Integrated exposure-uptake-biokinetic model for lead in children, Windows 32-bit version (IEUBKwin v1.1 build 11). Washington, DC: US Environmental Protection Agency.Google Scholar
- US EPA. (2011a). Exposure factors handbook: 2011 edition (No. EPA/600/R-09/052F). Washington, DC: National Center for Environmental Assessment, US Environmental Protection Agency. http://www.epa.gov/ncea/efh/report.html. Accessed 27 May 2013.
- US EPA. (2011b). Brownfields and urban agriculture: Interim guidelines for safe gardening practices—bf_urban_ag.pdf. http://www.epa.gov/brownfields/urbanag/pdf/bf_urban_ag.pdf. Accessed 19 March 2015.
- Van Holderbeke, M., Cornelis, C., Bierkens, J., & Torfs, R. (2008). Review of the soil ingestion pathway in human exposure assessment. Flanders: VITO/RIVM.Google Scholar
- WHO. (2011). Evaluation of certain food additives and contaminants (Seventy-third report of the Joint FAO/WHO Expert Committee on Food Additives). WHO Technical Report Series, No. 960, 2011.Google Scholar
- Wieland, B., Leith, A., & Rosen, C. (2010). Urban gardens and soil contaminants. University of Minnesota Extension & Hennepin County Department of Environmental Services. http://www.misa.umn.edu/prod/groups/cfans/@pub/@cfans/@misa/documents/asset/cfans_asset_287228.pdf. Accessed 17 March 2015.
- Zahran, S., Mielke, H. W., Gonzales, C. R., Powell, E. T., & Weiler, S. (2010). New Orleans before and after Hurricanes Katrina/Rita: A quasi-experiment of the association between soil lead and children’s blood lead. Environmental Science and Technology, 44(12), 4433–4440. doi: 10.1021/es100572s.CrossRefGoogle Scholar