Groundwater sources were likely to be contaminated by 12.7 times in the villages that have not become open defecation free (ODF) as compared to those free from open defecation, reveals a study by UNICEF.The study titled "The Environmental Impact of the Swachh Bharat Mission on Water, Soil and Food" also showed that the soil and food in the non-ODF villages were prone to have contaminated by 1.1 times and 2.16 times, respectively.It was released by Union Jal Shakti Minister Gajendra Singh Shekhawat and Union Environment Minister Prakash Javadekar here on the occasion of World Environment Day. The objective of the study was to assess the relationship between living in an ODF environment and the contamination levels of faecal bacteriological indicators found in water, soil and food sample taken from ODF and non-ODF villages.About 725 samples were collected from 12 ODF and 12 non-ODF villages, spread across West Bengal, Bihar and Odisha between December 2018 and January 2019. Finding of the study also showed that the relative risk of faecal contamination of piped water supply traceable to humans was 2.4 times more likely in non-ODF villages. In case of stored household water, the relative risk to human was 2.48 times more likely in non-ODF villages as compared to ODF villages.