Raina Margaret Maier
Interim Director, Institute of the Environment
Professor, BIO5 Institute
Professor, Environmental Science-Ext
Professor, Pharmaceutical Sciences
Professor, Pharmacology and Toxicology
Primary Department
Department Affiliations
(520) 621-7234
Research Interest
Raina M Maier, PhD, is a Professor of Environmental Microbiology in the Department of Soil, Water and Environmental Science and Director of the University of Arizona NIEHS Superfund Research Program. She also serves as Director of the University of Arizona Center for Environmentally Sustainable Mining and as Deputy Director of the TRIF Water Sustainability Program. Dr. Maier is internationally known for her work on microbial surfactants (biosurfactants) including discovery of a new class of biosurfactants and of novel applications for these unique materials in remediation and green technologies. She is also recognized for her work on the relationships between microbial diversity and ecosystem function in oligotrophic environments such as carbonate caves, the Atacama desert, and mine tailings. Dr. Maier has published over 100 original research papers, authored 23 book chapters, and holds a patent on the use of biosurfactants to control zoosporic plant pathogens. She is the lead author on the textbook “Environmental Microbiology” currently in its second edition.Dr. Maier emphasizes a multidisciplinary approach to her work and has served as PI or co-PI on several large granting efforts including the UA NIEHS Superfund Research Program, the UA NSF Kartchner Caverns Microbial Observatory, and the UA NSF Collaborative Research in Chemistry grant on biosurfactants.


Stein, M. M., Hrusch, C. L., Gozdz, J., Igartua, C., Pivniouk, V., Murray, S. E., Ledford, J. G., Marques dos Santos, M., Anderson, R. L., Metwali, N., Neilson, J. W., Maier, R. M., Gilbert, J. A., Holbreich, M., Thorne, P. S., Martinez, F. D., von Mutius, E., Vercelli, D., Ober, C., & Sperling, A. I. (2016). Innate Immunity and Asthma Risk in Amish and Hutterite Farm Children. The New England journal of medicine, 375(5), 411-21.
BIO5 Collaborators
Julie Ledford, Raina Margaret Maier, Fernando Martinez

The Amish and Hutterites are U.S. agricultural populations whose lifestyles are remarkably similar in many respects but whose farming practices, in particular, are distinct; the former follow traditional farming practices whereas the latter use industrialized farming practices. The populations also show striking disparities in the prevalence of asthma, and little is known about the immune responses underlying these disparities.

Monica D. Ramirez-Andreotta, ., Mark L. Brusseau, ., Paloma Beamer, ., & Raina M. Maier, . (2013). Home gardening near a mining site in an arsenic-endemic region of Arizona: Assessing arsenic exposure dose and risk via ingestion of home garden vegetables, soils, and water. Science of the Total Environment, 454-455, 373-382.
BIO5 Collaborators
Paloma Beamer, Raina Margaret Maier
Hogan, D. E., Curry, J. E., Pemberton, J. E., & Maier, R. M. (2017). Rhamnolipid biosurfactant complexation of rare earth elements. JOURNAL OF HAZARDOUS MATERIALS, 340, 171-178.
BIO5 Collaborators
Joan E Curry, Raina Margaret Maier
Curry, J., Baughman, K. F., Maier, R. M., Norris, T. A., Beam, B. M., Mudalige, A., Pemberton, J. E., & Curry, J. E. (2010). Evaporative deposition patterns of bacteria from a sessile drop: effect of changes in surface wettability due to exposure to a laboratory atmosphere. Langmuir : the ACS journal of surfaces and colloids, 26(10).
BIO5 Collaborators
Joan E Curry, Raina Margaret Maier

Evaporative deposition from a sessile drop is a simple and appealing way to deposit materials on a surface. In this work, we deposit living, motile colloidal particles (bacteria) on mica from drops of aqueous solution. We show for the first time that it is possible to produce a continuous variation in the deposition pattern from ring deposits to cellular pattern deposits by incremental changes in surface wettability which we achieve by timed exposure of the mica surface to the atmosphere. We show that it is possible to change the contact angle of the drop from less than 5 degrees to near 20 degrees by choice of atmospheric exposure time. This controls the extent of drop spreading, which in turn determines the architecture of the deposition pattern.

Hayes, S. M., O'Day, P. A., Webb, S. M., Maier, R. M., & Chorover, J. (2011). Changes in zinc speciation with mine tailings acidification in a semiarid weathering environment. Environmental Science and Technology, 45(17), 7166-7172.

PMID: 21761897;PMCID: PMC3175378;Abstract:

High concentrations of residual metal contaminants in mine tailings can be transported easily by wind and water, particularly when tailings remain unvegetated for decades following mining cessation, as is the case in semiarid landscapes. Understanding the speciation and mobility of contaminant metal(loid)s, particularly in surficial tailings, is essential to controlling their phytotoxicities and to revegetating impacted sites. In prior work, we showed that surficial tailings samples from the Klondyke State Superfund Site (AZ, USA), ranging in pH from 5.4 to 2.6, represent a weathering series, with acidification resulting from sulfide mineral oxidation, long-term Fe hydrolysis, and a concurrent decrease in total (6000 to 450 mg kg -1) and plant-available (590 to 75 mg kg -1) Zn due to leaching losses and changes in Zn speciation. Here, we used bulk and microfocused Zn K-edge X-ray absorption spectroscopy (XAS) data and a six-step sequential extraction procedure to determine tailings solid phase Zn speciation. Bulk sample spectra were fit by linear combination using three references: Zn-rich phyllosilicate (Zn 0.8talc), Zn sorbed to ferrihydrite (Zn adsFeOx), and zinc sulfate (ZnSO 4·7H 2O). Analyses indicate that Zn sorbed in tetrahedral coordination to poorly crystalline Fe and Mn (oxyhydr)oxides decreases with acidification in the weathering sequence, whereas octahedral zinc in sulfate minerals and crystalline Fe oxides undergoes a relative accumulation. Microscale analyses identified hetaerolite (ZnMn 2O 4), hemimorphite (Zn 4Si 2O 7(OH) 2·H 2O) and sphalerite (ZnS) as minor phases. Bulk and microfocused spectroscopy complement the chemical extraction results and highlight the importance of using a multimethod approach to interrogate complex tailings systems. © 2011 American Chemical Society.