Hydrogeology and human health

Authors: HYNDS, PAUL - Dublin Institute Of Technology; Borchardt, Mark; IBARAKI, MOTOMU - The Ohio State University

Submitted to: Hydrogeology Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/20/2017
Publication Date: 5/3/2017
Citation: Hynds, P., Borchardt, M.A., Ibaraki, M. 2017. Hydrogeology and human health. Hydrogeology Journal. 25:897-902.

Interpretive Summary: It is now widely accepted that groundwater used for drinking water is not necessarily pure and it can become contaminated with pathogens and chemicals that can affect human health. While much progress has been made, scientists’ understanding of groundwater contamination is still not complete because the research has focused on only a handful of pathogens and chemicals in only a few regions of the world. In this paper we discuss the future direction of groundwater contaminant research and areas in need of more information such as the accurate measurement of pathogen survival in real groundwater and the occurrence in groundwater of pharmaceuticals, endocrine disruptors, and microplastics. We also discuss how scientific advances can happen quickly when groundwater experts collaborate with experts in human health.

Technical Abstract: Over the past 50 years, significant progress has been made in improving our understanding of the extent and potential consequences of groundwater contamination, with research advancing on several fronts including groundwater sampling methods, laboratory detection methods, subsurface transport (and microbial survival) as related to hydrogeological concepts and colloid filtration theory, and the role of environmental factors such as temperature and precipitation. Nonetheless, data and knowledge gaps remain, necessitating significant further research in this area. Many excellent studies have been undertaken on the occurrence of pathogens and chemicals in groundwater, however, the data tend to be biased towards specific geographical regions and pathogen/chemical types. In the USA, for example, groundwater pathogen studies are over-represented in the upper Midwest, whereas few studies have been conducted in the South-eastern region. Subsurface pathogen studies have tended to focus on groundwater viruses, but there is a paucity of data on groundwater contamination by protozoan pathogens, with the same being true for many emerging organic contaminants including pharmaceuticals, endocrine disruptors, and microplastics. A significant proportion of studies on groundwater microbial contamination are conducted via laboratory microcosms or groundwater mesocosms. Such study designs likely do not adequately represent the direct and indirect effects on pathogen survival from attachment to aquifer sediments, predation from invertebrates and protozoa, bacterial pathogen growth from nutrient inputs into the aquifer, and the complex interactions with native microbial communities. The subsurface represents an extremely complex environment, characterized by significant spatial and temporal variability, which is almost impossible to accurately replicate. Thus, further studies are needed which seek to adequately account for the abiotic and biotic conditions found in natural groundwaters. Hydrogeologists possess an inherent understanding of the complex and unpredictable nature of groundwater contamination, and thus in collaboration with microbiologists, epidemiologists, geochemists, medical practitioners, and policy makers, they have an opportunity to help achieve global public health goals.