Vegetables grown on the Yamuna floodplain have been found to contain high doses of lead, which, on prolonged consumption, could trigger a range of diseases, including cancer, and damage organs, according to a new study by the National Environmental Engineering Research Institute (NEERI).
These vegetables are supplied to large wholesale mandis such as the ones in Azadpur, Ghazipur and Okhla and distributed further to be sold at weekly markets as well as by local vendors across the city, with the highest concentration being in east Delhi though a precise area-wise sales break-up is not available.
The heaviest lead contamination was found in coriander collected from east Delhi’s Geeta Colony. Except for cabbage, lead levels were found to be above the standard in all vegetables collected from vendors, with the highest level found in spinach (14.1 mg/kg). While the safe limit for lead in vegetables has been set at 2.5mg/kg by the Food Safety and Standards Authority of India (FSSAI), the level of the metal detected in vegetable samples collected from the floodplain ranges from 2.8mg/kg to 13.8mg/kg.
‘Samples of at least seven types of winter vegetables were collected from three different locations — Usmanpur, Mayur Vihar and Geeta Colony. They were tested for lead, mercury, nickel and cadmium. The level of lead in all the samples was found to be higher than Indian permissible limits. The level of other metals in the vegetables was within the limits,’ said SK Goyal, senior principal scientist and head of NEERI, Delhi.
The study was conducted in February 2019 by the NEERI, a research institute under the Council of Scientific and Industrial Research (CSIR). The findings were placed before the National Green Tribunal in May this year. An NGT-appointed committee had asked the NEERI to undertake the study following a Hindustan Times report on February 4.
‘The source of lead could be industries dealing in automobile parts, batteries, paint and polythene. Various kinds of usage of lead-based compounds may also be potential sources,’ said Goyal.
Heavy-metal toxicity can lower energy levels, damage the functioning of the brain, lungs, kidneys, and liver. They can also damage the blood composition and other important organs. Long-term exposure to these metals could even cause cancer, says the study.
‘Vegetables are regularly tested by the IARI (Indian Agricultural Research Institute) in Pusa and we have grown up eating these vegetables. We would consult the IARI scientists to find a solution to this problem. Vegetables grown close to the river (within 100m) could be toxic. But we are not sure where the lead is coming from,’ said Dalbir Singh, vice-president of the Delhi Peasants Multi-purpose Society.
Even though only 2% of the Yamuna’s stretch passes through Delhi, it receives around 70% of the Capital’s polluted water. In 2015, the NGT had banned the cultivation of edible crops and fodder on the floodplain saying that such vegetables were highly contaminated. Despite this, the practice continues.
‘Lead poisoning can lead to mental retardation in children. This is a serious issue and the authorities should immediately take action,’ said Manoj Misra of the Yamuna Jiye Abhiyan.
