Grassroots Science Detectives Solve Arsenic Mystery

Clinton Parks

Reporting on the #SciWri16 #GardenRoots session.

In 2008, the Environmental Protection Agency (EPA) added the Iron King Mine Humboldt Smelter Superfund site in Dewey-Humboldt, Arizona, to its National Priorities List. Concerned if they could safely eat vegetables grown in their gardens, local citizens met with EPA officials. To answer that question, the medically underserved and low-income community received help from Monìca Ramìrez-Andreotta -- then a doctoral student and a Superfund Research Program training fellow at the University of Arizona. But instead of taking the matter entirely in her hands, Ramìrez-Andreotta coordinated and collaborated with residents to analyze local arsenic levels and the potential risk to the vegetable gardeners in what would become the GardenRoots project.

Monìca Ramìrez-Andreotta, as a Latina woman and now University of Arizona Assistant Professor, defies the stereotype of the scientist as a white middle-aged man. But perhaps more importantly, she breaks other codifiers of that misrepresentation -- working in isolation and remaining dispassionate about her work. She not only works closely with the people who are impacted by her work; but, she involves them in her research. The excitement that Ramìrez-Andreotta has for her research and those it impacts is evident when she talks about her work.

Integrating Citizen Science with Environmental Justice

While this may seem like a new phenomenon, Ramìrez-Andreotta is quick to point out that before the professionalization of science, amateur enthusiasts providing scientific contributions was the norm, according to a Frontiers in Ecology and the Environment paper [Miller-Rushing 2012]. And even with the advent of professionalism in science, vocational scientists sometimes collaborated with citizens. No less an authority than Charles Darwin, the father of the theory of evolution, himself received data via citizen correspondence. Gardenroots integrates citizen science (public participation in scientific research), environmental justice, and professional science. That model utilizes environmental science, social science, public health, and visual communication to fully engage the community. Ramìrez-Andreotta shared that experience at the annual National Association of Science Writers (NASW) conference in San Antonio, Texas.

The Superfund Research Program, sponsored by the National Institute of Environmental Health Sciences, funds studies of hazardous substances and their impact on human health and the environment. Though Iron King Mine and the Humboldt Smelter have been shut down for nearly 50 years, harmful residue is still present mostly in mine tailings, which are leftovers created from the separation of the economically viable ore extract from the rest of the rock. The Iron King Mine and the Humboldt Smelter sites' tailings contained levels of lead and arsenic at about 350 and 130 times above background levels, respectively. Long-term exposure to either has been proven harmful to humans. Tailings "can then result in toxicity to humans, plants, or wildlife at downstream locations where they are deposited," according to an EPA report. Water contamination can occur from the Agua Fria River that flows through the former Humboldt Smelter site. "Tailings can also be blown by the wind from locations where there is no cover or crust over tailings piles and deposits," the EPA continues. "They can then mix into soils in locations downwind." more of a determinant for potential exposure to toxic substances

Ramìrez-Andreotta trained resident participants on how to collect vegetable, soil, and water samples. The trained participants then sent the sample kits to Ramìrez-Andreotta for analysis. She later used quality assurance and quality control techniques to validate the participants' findings. Specifically, Ramìrez-Andreotta measured arsenic concentrations in returned samples. Arsenic is the contaminant of concern at the Superfund site and was used in the risk assessment process since it is a known human carcinogen, Ramìrez-Andreotta said at the NASW meeting. She also provided the Dewey-Humboldt community with informational sessions on gardening, health, and a tour of the laboratories where their samples were being analyzed.

Initially overwhelmed by having received 85 different vegetable types, Ramìrez-Andreotta decided to separate the data dump by taxonomic family. The Asteraceae (lettuce) and Brassicaceae (radish, broccoli, kale, and cabbage) families contained the highest concentrations of arsenic. Three other vegetable families also had higher levels of arsenic than what had been found in a study of commercially sold vegetables, reported in the U.S. Food and Drug Administration Market Basket Study.

Ramìrez-Andreotta provided Dewey-Humboldt residents with raw data and ranges assessing vegetable consumption and approximate risk. Estimated risk was also provided based on water and soil samples. These data allowed residents to make informed decisions about how much they could consume from their garden and what risk that would entail. She also provided materials about gardening practices that would reduce their arsenic exposure.

But vegetables were the least of the Dewey-Humboldt community's concern regarding toxic chemical exposure. Arsenic levels were found to be highest from water -- from private wells and the public water system -- followed by incidental soil ingestion and then consumption of homegrown garden vegetables. Spurred by the unexpected finding that the town's water system's arsenic levels were above the federal drinking water standard, the study participants worked together to identify and notify households about the public water supply.

Further testing found that Dewey-Humboldt's high arsenic levels were not due to the Iron King Mine Humboldt Smelter Superfund site, but naturally occurring. As such, it was the responsibility of the state of Arizona to work with the public water supplier to find a solution. Residents took the issue of elevated arsenic levels to officials in state and federal government. Their advocacy paid off and in 2012 the Arizona Department of Environmental Quality issued a notice of violation that the public water system exceeded legal arsenic levels. Though Ramìrez-Andreotta and Gardenroots helped the community effect positive change, it was not until 2016 that arsenic levels were in compliance with the arsenic federal drinking water standard.

Motivated to Combat Environmental Racism

While the Dewey-Humboldt community is predominantly white -- about 95%, according to the 2000 U.S. Census -- communities of color are especially vulnerable to such environmental negligence. Race more than socioeconomic level is more of a determinant for potential exposure to toxic substances in this country, according to Jacqueline Patterson, director of the NAACP Environmental and Climate Justice Program. The most famous example is what has happened in Flint, Michigan. The predominantly black community has been exposed to dangerously elevated levels of lead in its drinking water.

Combating such environmental racism is a subject dear to Ramìrez-Andreotta. Thus, she has used Gardenroots as a template to affect change in her hometown of Tuscon, Arizona. She is heading a program that instructs "promotoras" (trained but nonprofessional community health workers) on climate change and environmental sustainability in the predominantly Hispanic southern part of her hometown. The project is called "Facilitating Community Action to Address Climate Change and Build Resiliency in Southern Metropolitan Tucson."

The promotoras are tasked with passing on what they have learned to the greater community to build a foundation for institutional knowledge within the community. The program is meant to provide information regarding climate change and environmental sustainability in order to ameliorate their negative impacts. The tools developed by the Gardenroots project are now being offered to anyone interested in learning more about their soil, plant, and water quality.

Ramìrez-Andreotta has a special connection with the Tuscon community. Like many there, she is "a second-generation Mexican American from Arizona. Growing up along the U.S.-Mexico border and being bilingual has helped me build trust," she says. "But also, being patient, transparent, ethical, and communicating effectively are very important -- even more important than my place of origin."

References or Relevant Literature

A. Miller-Rushing, R. Primack, & R. Bonney (2012) The history of public participation in ecological research, Frontiers in Ecology and the Environment, 10(6): 285-290

A.I. Roca (2016) #SciWri16 #GardenRoots, Storify, October 31

U.S. Environmental Protection Agency (2013) EPA to Conduct Field Work to Complete Cleanup Investigation; New Information About Residential Background and Soils, Iron King Mine / Humboldt Smelter Superfund Site Report, November

The citation for this article is:
C. Parks (2016) Grassroots Science Detectives Solve Arsenic Mystery. DiverseScholar 7:3

Clinton Parks is a Washington, DC-based freelance science writer who has written for AAAS' ScienceCareers, the American Chemical Society's Axial, and the American Physical Society's Physics Buzz, among others. Parks attended the ScienceWriters 2016 conference on a DiverseScholar SciComm Diversity Travel Fellowship. We thank mentor Matthew R. Francis, PhD for editing this article. Any opinions expressed in this article are solely those of the author.

Originally published 29-Dec-2016

Editor's Note

DiverseScholar is now publishing original written works. Submit article ideas by contacting us at This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Unported License.

License: Creative Commons Attribution Non Commercial No Derivative 3.0 Unported

Last updated: