Contents lists available at ScienceDirect Environmental Research journal homepage: www.elsevier.com/locate/envres Review article Hazardous heavy metals contamination of vegetables and food chain: Role of sustainable remediation approaches - A review Sandeep Kumar a,∗∗ , Shiv Prasad a , Krishna Kumar Yadav b,∗ , Manoj Shrivastava a , Neha Gupta b , Shivani Nagar c , Quang-Vu Bach d,∗∗∗ , Hesam Kamyab e , Shakeel A. Khan a , Sunita Yadav a , Lal Chand Malav f a Centre for Environment Science and Climate Resilient Agriculture, Indian Agricultural Research Institute, New Delhi 110012, India b Institute of Environment and Development Studies, Bundelkhand University, Kanpur Road, Jhansi 284128, India c Division of Plant Physiology, Indian Agricultural Research Institute, New Delhi 110012, India d Institute of Research and Development, Duy Tan University, Danang 550000, Viet Nam e UTM Razak School of Engineering and Advanced Technology, Universiti Teknologi Malaysia, Malaysia f National Bureau of Soil Survey and Land Use Planning, Nagpur, India ARTICLEINFO Keywords: Bioaccumulation Biotechnology Nanotechnology Toxicity Transgenic approach ABSTRACT This review emphasizes the role of toxic metal remediation approaches due to their broad sustainability and applicability. The rapid developmental processes can incorporate a large quantity of hazardous and unseen heavy metals in all the segments of the environment, including soil, water, air and plants. The released ha- zardous heavy metals (HHMs) entered into the food chain and biomagnifed into living beings via food and vegetable consumption and originate potentially health-threatening efects. The physical and chemical re- mediation approaches are restricted and localized and, mainly applied to wastewater and soils and not the plant. The nanotechnological, biotechnological and genetical approaches required to more rectifcation and sustain- ability. A cellular, molecular and nano-level understanding of the pathways and reactions are responsible for potentially toxic metals (TMs) accumulation. These approaches can enable the development of crop varieties with highly reduced concentrations of TMs in their consumable foods and vegetables. As a critical analysis by authors observed that nanoparticles could provide very high adaptability for both in-situ and ex-situ remediation of hazardous heavy metals (HHMs) in the environment. These methods could be used for the improvement of the inbuilt genetic potential and phytoremediation ability of plants by developing transgenic. These biological processes involve the transfer of gene of interest, which plays a role in hazardous metal uptake, transport, stabilization, inactivation and accumulation to increased host tolerance. This review identifed that use of na- noremediation and combined biotechnological and, transgenic could help to enhance phytoremediation ef- ciency in a sustainable way. 1. Introduction Worldwide, more than 10 million sites covering more than 20 million ha of land are considered soil polluted sites, of which > 50% are contaminated with hazardous heavy metals (HHMs) and/or me- talloids (He et al., 2015). The combined worldwide economic impact of heavy metals (HMs) pollution is estimated to be in excess of US $10 billion per year (He et al., 2015). A study by the Ministry of Environ- mental Protection (MEP), China, reported that the total area of arable land contaminated with heavy metals had reached near to 20 mha, estimating that almost 16.1% of the total arable land, and 19.4% of recognized cropland locations were above the normal range of heavy metals accumulation. Furthermore, 13.7%, 2.8%, 1.8% and 1.1% of arable land contained slight, mild, moderate and heavy pollution levels, respectively (Zhao et al., 2015; Sodango et al., 2018). According to the Central Water Commission (CWC) of India, 42 rivers have at least two HHMs beyond the permissible limit (CWC, 2018). As per Central Ground Water Board (CGWB), India, groundwater of more than 718 districts is afected by heavy metal toxicity with cadmium (Cd), chro- mium (Cr), arsenic (As), lead (Pb) and iron (Fe). The heavy metals in https://doi.org/10.1016/j.envres.2019.108792 Received 23 June 2019; Received in revised form 12 September 2019; Accepted 1 October 2019 ∗ Corresponding author. ∗∗ Corresponding author. ∗∗∗ Corresponding author. E-mail addresses: sandeep2011iari@gmail.com (S. Kumar), envirokrishna@gmail.com (K.K. Yadav), bachquangvu@duytan.edu.vn (Q.-V. Bach). Environmental Research 179 (2019) 108792 Available online 03 October 2019 0013-9351/ © 2019 Elsevier Inc. All rights reserved. T