Environment International 155 (2021) 106582
Available online 30 April 2021
0160-4120/© 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/).
A citizen science approach to identifying trace metal contamination risks in
urban gardens
Mark Patrick Taylor
a
,
*
, Cynthia F. Isley
a
, Kara L. Fry
a
, Xiaochi Liu
a
,
c
, Max M. Gillings
a
,
Marek Rouillon
a
, Neda S. Soltani
a
, Damian B. Gore
a
, Gabriel M. Filippelli
b
a
Department of Earth and Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, New South Wales 2109, Australia
b
Department of Earth Sciences and Center for Urban Health, Indiana University – Purdue University Indianapolis, Indianapolis, IN, USA
c
School of Information Engineering, China University of Geosciences, Beijing 100083, China
ARTICLE INFO
Handling Editor: Olga-Ioanna Kalantzi
Keywords:
Trace metals
Exposure
Human health
Soil
ABSTRACT
We launched the VegeSafe program in 2013 to assist Australians concerned about exposure to contaminants in
their soils and gardens. VegeSafe analyses garden soils provided by citizens for trace metals at our laboratory at
little to no cost, with easy-to-follow guidance on any intervention required. The response was over-
whelming—Australians submitted 17,256 soils from 3,609 homes, and in turn VegeSafe researchers now have
unparalleled household-scale data, providing new insights into urban trace metal contamination. The results are
sobering, with 35% of homes, particularly those that are older, painted and located in inner cities having soils
above the Australian residential guideline (300 mg/kg) for the neurotoxic trace metal lead (Pb). Exposure
pathway, blood Pb concentration and vegetable uptake modelling showed the communities in these locations
were most at risk. VegeSafe is transformative: 94% of participants better understood contaminants, 83% felt safer
in their home environment and 40% undertook remedial action based on their results. The two-way nature of this
program enables education of citizens about environmental contaminants, advances public health, and delivers
impactful science.
1. Introduction
Urban gardening has experienced a renaissance, driven by commu-
nity desire for home-grown produce. Urban croplands represent 5.9%
(67.4 Mha) of global cropland (Thebo et al. 2014), with 35% of USA
residents (National Gardening Association 2014) and 52% of Australians
(Wise 2014) producing some food in their gardens. There are multiple
advantages of urban food production (Ives et al. 2018; Winkler et al.
2019), including increased condence about the source and quality of
produce (Chase 2015) and enhanced urban health and sustainability.
Urban gardens may have legacy trace metal contamination from build-
ing, industry, transport and waste practices (Rouillon et al. 2017a; US
EPA 2011a). Urban gardeners typically have little awareness of these
problems and little agency in determining whether or not their indi-
vidual gardening plot is contaminated with trace metals. In 1980, Pat-
terson predicted that urban city landscapes would be rendered
uninhabitable due to the “millions of tons of poisonous industrial lead
residues” (National Research Council 1980). This study examines the
legacy risks in Australian garden soils associated, in part, with leaded
petrol emissions (Kristensen 2015) and the decay of lead-based paint on
older buildings.
The problem of legacy trace metal contamination is concerning, as
urban vegetable gardens can contain anthropogenic contamination from
toxic trace metals and metalloids (hereafter trace metals), including lead
(Pb) (Cheng et al. 2015; Filippelli et al. 2018; Laidlaw et al. 2018;
Rouillon et al. 2017a; Spliethoff et al. 2016). Urban environments are
also known to be impacted by a suite of non-metal contaminants, all of
which present toxic risks, including per- and polyuoroalkyl chemicals,
petroleum hydrocarbons, pesticides, weedicides and asbestos bres. The
spatial heterogeneity of urban soil contamination across cities and in-
dividual garden lots is not well understood by the community. This
knowledge barrier, coupled with insufcient geochemical testing means
there is limited information about specic exposure risks at residential
locations or what to do about them (Bechet et al. 2018).
The primary barriers for residents acquiring soil trace metal data are
awareness, cost and access. Moreover, commercial laboratories do not
* Corresponding author.
E-mail address: [email protected] (M.P. Taylor).
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Environment International
journal homepage: www.elsevier.com/locate/envint
https://doi.org/10.1016/j.envint.2021.106582
Received 26 January 2021; Received in revised form 8 April 2021; Accepted 13 April 2021