Social Beliefs and Norms of Arsenic Contamination

This experimental study examines the beliefs and social norms surrounding arsenic contamination of groundwater in order to encourage healthier and safer water usage practices.

Arsenic contamination of groundwater is a rising concern in Bihar with studies pointing towards high arsenic presence and subsequent groundwater contamination in atleast 15 districts and 57 blocks in the state. Arsenic contamination results in severe health concerns, the detrimental effects spilling over into economic outputs as well. Previous studies have found that a lack of awareness of the ill effects of arsenic contamination amongst people is one of the sources for its widespread health implications. This experimental study  examines the beliefs and social norms surrounding arsenic contamination in order to better identify behavioural precedents. It attempts to understand the impact of increasing awareness of water quality on reshaping norms and behaviours surrounding water usage towards safer and healthier water usage practices.

This study is being conducted in partnership with the Max Planck Institute (MPI) in the state of Bihar. The randomised evaluation was conducted in two districts – Samastipur and Begusarai, covering 150 villages. The survey covered 2333 households during the baseline, revisiting 2316 of them during the endline survey. The survey instrument, designed by MPI, captured data on household characteristics, social norms, water-use practices time and water tests for arsenic contamination. Two sets of videos were shown to the respondents as part of the intervention measures; the treatment group was shown a video covering the ill-effects of arsenic contamination in water while the control group was shown a video on wildlife conservation. the treatment arm was further split into two – individual and group; for the first group, the treatment video was shown to selected individuals while it was shown to groups of three respondents for the latter group. The endline surveys were phased to phone surveys in light of the COVID-19 pandemic.

Key Findings

The study finds that there were significant changes in the quantity of arsenic in the primary drinking water for our treatment groups (when pooled together). Results show that there is a reduction of arsenic level by 5 microgram per liter, which is sizable considering it is half of the WHO recommended unhealthy level. This change was substantiated by a 3-percentage point increase in reported behavioral change in water treatment practices. This was achieved both with an increase in healthy water practices and a decrease in unhealthy water practices. There was an increase in arsenic knowledge, as measured by a test administered for the information that the intervention contained. 


The results suggest that the low-cost/low-effort recommendations and increasing knowledge were the most important reasons for the effectiveness of the intervention. The study observed no clear effects on most health outcomes in the short-term, however, we do see a significant reduction in mental health issues in the treatment groups even in this short gestation period. Findings from the study have important implications for policies that seek to influence water usage practices. 

Thematic Area

Institutions and Society

Project Leads

Sujatha Srinivasan




Max Planck Institute