PlomBoxear: A Device for Open Source Metrology to Fight Lead Contamination in Drinking Water

This project aims to translate research funded by a 2017 STFC GCRF Foundation Award to deliver an open-source, low-cost device to measure lead (Pb) contamination in drinking water.

This project draws on an area of research supported by the STFC core science programme: ultra-precise radioactivity measurement and calorimetry developed to search for dark matter. The predecessor GCRF project built upon this research to develop detection of Pb in water using interactions of radioactivity emitted from Pb atoms in CMOS sensors, together with data acquisition (DAQ) via a mobile phone. This project aims to translate these developments to application in a low-cost device, and demonstrate its utility for measuring Pb contamination in water in a pilot study in Argentina. Development and validation activities will be carried out across the UK, Argentina and México.

The motivation for growing capacity for and developing new Pb measurement techniques is that Pb pollution is the #1 cause of loss of life expectancy in the world, and currently 2 of the top 10 worst pollution problems in the world are associated with Pb [1]. This is a problem both in LMICs and in high income countries- examples like the Flint, Michigan, USA, water safety breaches demonstrate that water quality in violation of World Health Organization (WHO) guidelines can happen anywhere, and information about water quality, and its variation in time, is not widespread. Even 'clean' technologies, like electric cars, employ traditional Pb-based batteries; the disposal of these batteries is a leading contributor to Pb pollution in drinking water, particularly in LMICs.

Currently, Pb in water measurements require expensive, specialized equipment to reach relevant sensitivity levels for human health- even 0.1 parts per million contamination with Pb produces devastating biological impacts. The device we propose to develop, the PlomBox, will use a custom sensor assembly box that plugs into a mobile phone to acquire and analyze the data. We aim for the box cost to be <10 GBP. The goal is to make widely-distributed metrology and real-time, crowd-sourced monitoring of Pb levels in drinking water possible for the first time. This technology could have a transformative impact on the public health problems associated with Pb pollution.

The World Health Organization (WHO) limit for Pb in drinking water is 10 parts per billion (ppb). Reaching this level of sensitivity is an incredibly challenging problem, which we address by leveraging the precision calorimetry techniques for Pb in silicon (Si) detectors demonstrated in the predecessor GCRF project, together with biological techniques to detect trace impurities using engineered bacteria demonstrated by the U. of Buenos Aires collaborators.

We request support for 873k over 18 months to support PDRAs and Technicians in Argentina (5), México (3), and the UK (3), travel, and consumables costs to fabricate the PlomBox prototypes, deploy them in a field test, cross-validate against Germanium (Ge) detector gamma spectroscopy and inductively coupled plasma mass spectrometry (ICP-MS).

[1] http://www.worstpolluted.org/

This proposal aims to develop pathways to translate the expertise in material radio-assay developed for particle astrophysics and bacteria engineering techniques developed for synthetic biology into impact on human health, through quantifying the incidence of a leading environmental toxin, lead. The ultimate goal is to reduce the health impacts of lead pollution. This project takes the approach that the first problem to address is to develop open source tools that can be widely applied to quantify the presence of lead, pursuing the idea that what can be measured can then be improved.

Lead exposure accounts for over 850,000 deaths each year due to long-term effects on health, with the highest burden in LMICs. The Institute for Health Metrics and Evaluation also estimates that lead exposure accounts for 9% of the global burden of idiopathic intellectual disability, 4% of the global burden of ischaemic hearth disease, and 7% of the global burden of stroke [1]. Children absorb more lead and are particularly vulnerable, with early childhood exposure known to lead to behavioral problems in adolescence, IQ decrements, cognitive impairment, and decreased visuo-spatial skills. Although there is no known level of lead exposure considered to be safe, lead and other heavy metals are still widely used in the production of consumer goods. In LMICs, inadequate regulation, informality of many industries, poor surveillance, and improper disposal of contaminants can result in dangerous exposures to nearby residents [2]. Mexico is the world's 5th largest producer of lead and 40% of its production is used locally in various industrial processes that cause lead contamination of the environment. Argentina similarly suffers from environmental exposure and lack of quantification of hazards or exposure at the point of water use in rural environments.

This work aims to deliver smart technology that can rapidly evaluate lead content in food and water using mobile instruments, eliminating the need for expensive and time consuming laboratory measurements, and minimising health risks through immediate identification and alerts of toxicity. Measurements of Pb-210 using the CMOS-based technology will be validated against existing BEGe gamma spectroscopy detectors we have developed at Boulby, delivering world-leading sensitivity at <10 mBq/kg [3]. The Pb-210 to total lead content will be correlated using our ICP-MS facility at RHUL.

If the outcomes of this project are all realized, we will demonstrate the utility of a device costing 10 GBP for widespread use by affected communities. This will both provide water safety information to communities, and develop a real-time geographical map of Pb pollution which can be used by municipalities and NGOs to best target Pb mitigation efforts.

[1] Institute for Health Metrics and Evaluation (IHME). GBD Compare.
[2] https://ehjournal.biomedcentral.com/articles/10.1186/s12940-016-0151-y
[3] "Low Background Gamma Spectroscopy at the Boulby Underground Laboratory", arXiv:1708.06086 (2017)