Dangerous levels of arsenic are present in the soils and water of the Cerrito Blanco community in central Mexico. Arsenic contamination in the semi-desert area is 2,500 times higher than the limit set by the World Health Organisation, causing poor crop productivity and posing a serious health risk to the people living there.
Responding to this urgent problem, researchers from Mexico and the UK worked closely with members of the community to locate the source of contamination and implement several successful interventions; raising awareness about the risk of exposure, and improving crop safety and community health.
Supported by Newton funding, the research team implemented a traffic light alert system to help the community distinguish between contaminated and non-contaminated water, and produced a visual guide to help farmers to recognise contaminated crops. A campaign video publicised in the local news helped to raise public awareness and the research team have directed people to alternative arsenic-free groundwater sources. As a result of the interventions, maize yields are significantly higher than preceding years, reaching up to one tonne per hectare for rain-fed crops without the use of fertiliser.
The scientists are also working with community members, the Human Rights Commission in Mexico and other partners to ensure that their right to access clean water and safe food is protected. By strengthening relationships with community members and establishing new partnerships with the private sector, the researchers want to attract investment for the remediation of arsenic contaminated soil to secure the social and economic development of the community.
"Increased awareness of arsenic contamination has helped Cerrito Blanco communities make the right decisions for their wellbeing."
Dr Bhaskar Sen Gupta, Heriot-Watt University
Distribution of arsenic on agricultural soils and its influence on exposure risks through maize ingestion and agricultural activities in Matehuala, San Luis Potosi, Mexico
Project leads: Nadia Martinez-Villegas, Professor in Water Technology, Potosi Institute for Scientific and Technological Research AC (IPICyT) and Professor Bhaskar Sen Gupta, Heriot-Watt University
Delivery partners: Mexican Academy of Sciences (AMC), IPICyT (Potosi Institute of Scientific and Technological Research) and the National Council of Science and Technology (CONACyT)