Biomonitoring: Measuring Chemicals in People

Doug Farquhar 8/23/2017

image of a chemist's hand in a lab holding a beaker containing an unidentified substance


"'Biomonitoring’ provides a scientific basis when developing regulations," says California Assemblywoman Wilma Chan, Health Committee chair and a supporter of California’s biomonitoring program.  
One of the most critical concerns in enacting state legislation is whether the law has any impact, whether it is providing the intended results.

In California, a 2003 law banned flame retardants containing Polybrominated Diphenyl Ethers (PBDEs), a chemical that potentially interferes with hormones, may harm developing fetuses and infants, and may cause cancer. The intent was that a ban would reduce the amount of PBDE in people, even though the chemical would persist in the environment (since it breaks down slowly).

PBDEs were commonly used in furniture, infant products, electronics and other materials to prevent the product from catching fire. Many states have sought to ban or limit the use of these chemicals. States that have banned or restrict the use of PBDEs include California, Hawaii, Illinois, Maine, Maryland, Michigan, Minnesota, New York, Oregon, Rhode Island, Vermont, and Washington.

After much deliberation, the California legislature chose to ban PBDEs. The ban would reduce the amount of PBDEs in the environment, but the question remained: would the ban reduce the amount of PBDEs in people?

California was one of many states with concerns about the chemicals Polybrominated Diphenyl Ethers (PBDEs), common flame retardants added to furniture, infant products and electronics. The University of California at San Francisco (UCSF) performed a study determining the level of PBDEs in pregnant women and discovered the chemical was prevalent. This led the legislature to enact AB 302 (2003 Sess.) banning the chemical in consumer products. The ban went into effect in 2008.

The answer came from a biomonitoring study—measuring the amount of these chemicals in people, instead of in the environment. The University of California San Francisco (UCSF) collected blood samples from pregnant women in two separate studies, one in 2008-2009 and a follow-up study in 2012. The samples were tested by the state public health lab for PBDEs. The laboratory measured a 39 percent decrease in PBDE levels between the two studies, showing evidence that the ban was in fact working. However, Californians continue to have the highest measured PBDE levels in the world because of extensive past use of these flame retardant chemicals and their continued presence in older furniture, electronics and other materials present in homes in California. Biomonitoring provided evidence that the 2003 law was performing as it was intended. 

Rather than studying the chemical in the environment, the state lab used biomonitoring, studying the amount of the chemical in people. This approach provided more accurate data to determine whether the ban had its intended effect.


State and federal environmental health labs have begun to engage in biomonitoring—the measurement of human exposure to chemicals in the environment. Biomonitoring provides insight into whether specific chemicals are getting into and being retained in the body.

Through state and federal programs like the Toxic Release Inventory and the Toxic Substances Control Act, public and environmental health agencies have a good sense of the amount of chemicals released into the environment (air, water and soil). But whether these chemicals are accumulating in people is not as well understood.

Biomonitoring provides the answer of whether chemicals could impact human health. By measuring the chemicals or metabolites in blood, urine or other clinical specimens, laboratories can learn the extent to which bodies are absorbing a chemical, and whether that chemical persists in people.

Public health and environmental agencies use biomonitoring to:

  • Determine people’s exposure to a chemical following an incident.
  • Gather information on trends, whether a certain chemical is increasing or declining in a population or subgroup.
  • Evaluate public health interventions to determine their success.
  • Prioritize environmental health resources.

Biomonitoring is the measuring of chemicals in the human body, specifically in blood, urine, serum, saliva or tissues. Measuring chemicals in human tissues is a highly effective means to assess human exposure to pollution. Biomonitoring results are used to help make decisions about how best to protect people from diseases, birth defects, disabilities, dysfunction and death.

By identifying the chemicals present and their extent in the population, biomonitoring provides a scientific foundation for policy decisions. It can determine whether a policy or legislation has performed as intended, or whether that policy should be amended or even repealed.

Biomonitoring helps legislators answer key public health questions, such as:

  • Do pesticides pose a risk to constituents who farm, live near farms or eat certain types of food?
  • Are contaminants in drinking water causing a health threat or risk to residents?
  • Have a state’s no-smoking policies effectively reduced tobacco smoke exposure in non-smokers?
  • Do increased levels of mercury, dioxin or polychlorinated biphenyls (PCBs) in game fish threaten a community’s health? 
  • In the event of a suspected terrorist attack, did the attackers use chemical or radiological weapons? Who was exposed and who needs medical treatment?

One of the core principles in public health is epidemiology. Epidemiology is the study and analysis of the patterns, causes and effects of health and disease conditions in defined populations. It is the cornerstone of public health, shaping policy decisions and evidence-based practice by identifying risk factors for disease and targets for preventive health care. Epidemiology is data-driven and relies on a systematic and unbiased approach to the collection, analysis and interpretation of data. It uses sound research methods to determine the frequency of health events and their pattern in a population, telling researchers the nature and extent of a public health concern. It originally addressed epidemics of communicable diseases, but has been expanded into public health concerns such as chronic diseases, birth defects, injuries, occupational health and environmental health. These same principles apply to biomonitoring. By gathering data on chemicals and pollutants in the environment, public health researchers can determine patterns within the population, whether a particular chemical or pollutant is an actual threat and how to respond to that threat.

Biomonitoring and the CDC

The U.S. Centers for Disease Control and Prevention (CDC) has used biomonitoring to determine key information about the public’s health and exposure to chemicals. Through its National Biomonitoring Program, the CDC’s Environmental Health Laboratory assesses the U.S. population’s exposure to environmental chemicals. It collaborates on studies to examine vulnerable populations, such as newborns, children, pregnant women and population groups or communities known or likely to have higher exposures.

National Health and Nutrition Examination Survey and the National Exposure Report

To assess the U.S. population’s exposure to chemicals, CDC measures chemicals or their metabolites in the blood and urine from participants through the National Health and Nutrition Examination Survey (NHANES), a program of studies designed to assess the health and nutritional status of adults and children in the United States, performed every other year, with the latest data from the years 2013-14. The survey, or series of surveys, combines interviews, physical examinations, and blood and urine collection to determine the health status, health-related behaviors and nutrition of the U.S. population. The report provides estimates of exposures on a national basis; it does not provide state-by-state estimates. NHANES is a major program of the National Center for Health Statistics (NCHS) at the Centers for Disease Control and Prevention (CDC). NCHS produces vital health statistics for the nation.

CDC uses the NHANES data to produce the National Exposure Report on Human Exposure to Environmental Chemicals. This report, more commonly known as the National Exposure Report, is an ongoing assessment of the U.S. population’s exposure to environmental chemicals through the collection of blood and urine data from the NHANES.

The report cautions that the presence of an environmental chemical in a person’s blood or urine does not mean that it will cause adverse health effects or disease. The toxicity of a chemical is related to its dose or concentration, in addition to an individual person’s susceptibility. Small amounts may be of no health consequence, whereas larger amounts may cause adverse health effects.

Research outside of the NHANES or National Exposure Report identifies those environmental chemicals that may be a health concern and at what levels. Certain chemicals have shown not to cause adverse health effects, and are therefore not tracked. But for other chemicals, such as lead, researchers have a good understanding of the health risks associated with various blood levels. Most of the environmental chemicals identified by NHANES or listed in the report require more research to determine whether exposure and at what level is cause for concern.

The latest release of the National Exposure Report, known as the Fourth Report, identified the benefits of such research:

  • Determining which chemicals get into Americans’ bodies and at what concentrations.
  • Determining what proportion of the population have levels above those associated with adverse health effects for chemicals with a known toxicity level.
  • Establishing reference values that can be used by physicians and scientists to determine whether a person of group has an unusually high exposure.
  • Assessing the effectiveness of public health efforts to reduce exposure of Americans to track levels over time.
  • Determining whether exposure levels are higher among minorities, children, women of childbearing age, or other special group.
  • Directing priorities for research on human health effects from exposure.

The report tracks the prevalence of 212 chemicals, identifying the reference level in the 95 percentiles of the participants (meaning 95 percent of the population have levels of a chemical below the NHANES amount). Public health officials can use these references to determine whether groups have high levels of a chemical compared to the rest of the population.

Of these 212 chemicals, a few stand out. Some of the more common chemicals found in the U.S. population include polybrominated diphenyl ethers (PBDEs) (used as a flame retardant), Bisphenol A (BPA) (used in plastics and resins), perchlorate (used in explosives and fireworks) and perfluoroalykl substance chemicals (PFAS) (used to make carpets and clothing stain resistant and non-stick cookware). Mercury exposure is highlighted in the Fourth Report, which shows total blood methyl mercury (which comes primarily from eating seafood) levels increase with age, but decline after age 50. The report also looked at various forms of arsenic, to determine which forms adversely impact human health.

The report notes a dramatic decline in environmental tobacco smoke in non-smokers. Levels of cotinine (a marker of tobacco smoke) in non-smokers dropped 70 percent from earlier reports, showing public health efforts to reduce exposure to tobacco smoke successful. Cotinine is a metabolite of nicotine, which is commonly found in smokers but should not be found in non-smokers, unless they inhale environmental tobacco smoke.

NHANES is a national survey, not a regional or state-based survey. Its findings are designed to reflect exposures in the nation overall, rather than individual counties or states. Producing accurate estimates at a state or local level would require a much larger and very different sample design. Consequently, results might not be comparable to other states or localities or allow examination of trends in chemical exposures.

To produce individual state NHANES data, states would need to conduct biomonitoring assessments statewide or in communities or groups where chemical exposure is a concern. State biomonitoring programs can produce state- or community-specific exposure data that can be compared to results in CDC’s exposure report. By comparing state biomonitoring data against the NHANES, states could determine whether a person or groups of people have an unusually high (or low) exposure to a chemical or environmental health threat.

National Exposure Report defines an environmental chemical as a chemical compound or chemical element present in air, water, food, soil, dust, or other environmental media, such as consumer products. Blood and urine levels reflect the amount of the chemical that actually gets into the human body from the environment (internal dose). Either the chemical or its metabolite is measured. A metabolite is a substance produced when body tissues chemically alters the original compound. 

CDC launched the State Biomonitoring Cooperative Agreementto increase the capability and capacity of states to conduct biomonitoring and state population-based biomonitoring surveillance to assess human exposure to environmental chemicals. CDC’s National Biomonitoring Program has developed data collection protocols and guidelines for states to follow. 

US map showing state biomonitoring programs.

The federal government has supported the collection of biomonitoring data in communities nationwide but lacks state-level data. Identifying an environmental or chemical exposure in a single state requires a state biomonitoring program, targeted to address the affected population in that state. State biomonitoring programs provide specific data on state-level health results, offering policymakers insight into the health needs and concerns of their state. But state biomonitoring programs are limited.

With adequate state-level biomonitoring capacity and capability, states can:

  • Focus on contaminants that are prevalent or emerging in the state or local communities, targeting scarce resources to critical need areas.
  • Develop a comprehensive understanding of exposure levels among state residents, measuring changes in chemical exposure over time.
  • Identify and track exposure trends and identify disparities that affect specific communities.
  • Inform and evaluate programs and policies to reduce exposures.

State legislatures can help build state biomonitoring capacity by establishing statewide programs or pilot projects and providing state public health laboratories with the personnel, resources and equipment necessary to conduct biomonitoring investigations.

State Biomonitoring Programs

State biomonitoring programs primarily fall into three categories: 

  • General surveillance
  • Targeted investigations 
  • Emergency response

Public Health Surveillance

Biomonitoring may be conducted for the purpose of detecting and measuring differences in the public’s exposure to a chemical or as a way to evaluate the effectiveness of actions to reduce exposure. By performing biomonitoring on a specific group or community and comparing the results against the national NHANES results, the lab can determine whether there is an anomaly—whether that group or community has a different level of a specific chemical.

This is commonly used to determine elevated levels of lead in a community. A result significantly different than the NHANES level could indicate a specific environmental exposure.

Targeted Investigations

This approach works with a specified community, responding to concerns about chemical exposure in a population. This model is used to investigate chemical exposures in people who may have been exposed to a chemical release or occurrence. If a release occurs, the state can use biomonitoring to determine who was or was not affected by the release and whether further medical follow-up is needed. It can be used to calm the fears of those exposed.

The New York Legislature is looking into this approach with SB 195 (2017 Sess.). This bill directs the Commissioner of Health to conduct a biomonitoring study in the residents of the towns of Hoosick Falls, Hoosick and Petersburgh to document the residents' actual exposure to PFOA (perfluorooctanoic acid). The chemical was discovered in the river that provides these towns’ drinking water supply. This study would determine whether the PFOA made it into the residents of these towns.

Emergency Response

In the case of a chemical spill or other emergency, biomonitoring has been used to determine if those exposed were poisoned and to assess the need for medical treatment. The approach is similar to a disease outbreak investigation. Those exposed are quickly identified and their specimens collected. State health officials provide the necessary laboratory or toxicology support to analyze the specimens. Medical professionals provide diagnosis and follow-up. Epidemiologists may be involved to track outcomes over the course of the response, and to design further investigations.

In Massachusetts, the Department of Health used biomonitoring in response to a mercury spill at a large middle school. The department found mercury contamination in the school and surrounding neighborhood but was uncertain if any students were exposed. The state health lab measured mercury levels in urine samples to determine that most people did not have excessive levels. Ones that did have high levels were referred for medical treatment.

State Legislatures 

State Legislatures have begun to study biomonitoring as an option for effective environmental health policy development, and the issue is gaining support. In 2017, five states included a biomonitoring effort in their state’s appropriation; another six had legislation including a biomonitoring component. In comparison, in 2015 only 3 states had bills mentioning biomonitoring.

Biomonitoring 20017 Legislation map.

















2017 State Legislation

In previous years state legislatures reviewed biomonitoring efforts, though not to the extent as was seen in 2017.

  • Illinois looked at the feasibility of initiating a statewide biomonitoring effort in 2007 and again in the 2015-2016 session. Both times the bills failed. However, in 2010, the Maryland General Assembly enacted a law that included a study on a biomonitoring program within the Department of Health and Mental Hygiene.
  • In 2016, the legislature in Pennsylvania adopted a provision encouraging the federal Environmental Protection Agency (EPA) to perform biomonitoring for residents and military personnel who had been exposed to contaminated drinking water.
  • California in 2006 and Minnesota in 2007 enacted laws establishing permanent biomonitoring programs within their states. The California Environmental Contaminant Biomonitoring Program created the state’s biomonitoring program to monitor the presence and concentration of specified chemicals. In Minnesota, the legislature enacted the Healthy Minnesotans Biomonitoring Program to conduct biomonitoring of communities and groups on a voluntary basis.

State Leaders in Biomonitoring

The programs in California and Minnesota are leaders in biomonitoring. The authorizing legislation ensures the sustainability of the program, meaning the lab can invest in biomonitoring activities with an assurance that the program will continue. It also allows the state, rather than the federal government, to determine which efforts to engage in biomonitoring, providing the lab more discretion over the study.

California’s Biomonitoring Program

The California Environmental Contaminant Biomonitoring Program was created by Senate Bill 1379 in 2006 to “provide data that will help California scientists, researchers, public health personnel, and community members explore linkages between chemicals exposure and health.” In enacting the law, the legislature believed that data would:

  • Identify highly exposed communities.
  • Explore linkages between chemical exposures and specific health outcomes.
  • Inform health responses to unanticipated emergency exposures.
  • Assess the effectiveness of current regulations, and set priorities for reform.

Because the state uses over a quarter of the most toxic pesticides in the nation and has a series of high-tech industries that use chemicals that are not used in other parts of the country, the legislature sought a biomonitoring law that focuses specifically on human exposure, rather than addressing environmental concerns. Their objective was to determine whether these chemicals found in the environment were also accumulating in people, to give the public guidance as to how to respond to the use of these chemicals. Other objectives include looking at chemical exposures over time, identifying highly-exposed communities, and evaluating the effectiveness of chemical policy.

The California legislation defines biomonitoring as “the process by which chemicals and their metabolites are identified and measured within different biological specimens.” It discusses chemicals that “are found in cosmetics, personal care products, pesticides, food dyes, cleaning products, fuels, and plastics” and are ubiquitous “in modern life.” It then goes on to define ‘biological specimen’ as “a sample taken from a biophysical substance, that is reasonably available within a human body, for use as a medium to measure the presence and concentration of toxic chemicals.” California regulations also define ‘Environmental Health Surveillance’ as the ability of government and university investigators and public health officials to assess the impact of environmental contaminants on the human body.

The program is a collaborative effort involving the state Department of Public Health, the Office of Environmental Health Hazard Assessment and the Department of Toxic Substances Control.

Between this and other efforts by the legislature, California has become a leader in identifying chemicals of emerging concern in the environment and consumer products. The Biomonitoring program contributes to this effort by developing methods to identify new chemicals that may be found and are a potential risk to the public.

Biomonitoring California has engaged in several efforts, including building laboratory capabilities, developing techniques to appropriately communicate results of individual tests to participants, and performing targeted studies of vulnerable subpopulations. The program has developed the ability to measure almost 200 priority chemicals in the state’s population, placing a priority on monitoring chemical exposure in vulnerable subpopulations – disadvantaged communities with exposure concerns, employees in workplaces with high concentrations of chemicals of concern, and sensitive populations such as pregnant women.

Overall, the program conducted more than 7000 biomonitoring analyses for toxic chemicals including heavy metals, flame retardants, phthalates, and pesticides. The results of this effort include:

  • The measurement of almost 200 distinct chemicals or their breakdown products in urine, serum, and whole blood. Many of these chemicals have the potential to adversely impact public health.
  • Conducting 20 biomonitoring studies with 30 collaborators.
  • Obtaining specimens from more than 7000 people in the state.
  • Building the laboratory capacity to conduct more than 4000 analyses each year.
  • Providing the individual results to participants upon their request.
  • Serving as a warning system for new chemical exposures and support the state’s environmental and occupational health policies.
  • Demonstrating the effectiveness of public health efforts to reduce chemical exposures. Promoting transparency and collaboration by sharing study finding, practical knowledge, and program activities.

As of 2017, the state has conducted almost 20 biomonitoring studies. Two biomonitoring studies that have been recently completed and a third is partially completed are the Maternal and Infant Environmental Exposure Project, the Firefighter Occupational Exposure Project and the Biomonitoring Exposure Study in the Central Valley (which is in its final stages).

The Maternal and Infant Environmental Exposure Project

The Maternal and Infant Environmental Exposure Project (MIEEP) involves the state program along with two university programs to measure environmental chemical exposures in 65 mothers and their infants and 27 pregnant women. Infants in the study had higher levels of certain chemicals as compared to the mothers. The flame-retardant PBDE was found in higher levels in infants even though the chemical had been banned. The study analyzed samples for 59 chemicals, of which 50 were detected.

The Firefighter Occupational Exposure Project

The Firefighter Occupational Exposure Project (FOX) studied 101 firefighters in Southern California and measured high levels of PBDEs and benzophenone-3 (BP-3) in firefighters. Firefighters in frontline activities had higher levels of PBDEs, a class of flame retardant chemicals. Use of personal protective gear and regular cleaning were associated with lower levels of the chemical.

The Biomonitoring Exposure Study

The Biomonitoring Exposures Study (BEST) was a joint effort between Biomonitoring California and the Kaiser Permanente Northern California (KPNC) Division of Research. The study sought to measure environmental chemical exposures in adults living in the Central Valley served by KPNC in two separate studies.

BEST studied over 500 adults, collecting blood and urine samples, to gain a sense of the extent of environmental chemicals in the population of the Central Valley. The preliminary results show higher levels of the toxic metal arsenic. The state is performing a final analysis regarding the results.

Minnesota’s Environmental Public Health Tracking and Biomonitoring Program

Created in 2007 by the Minnesota Legislature the Environmental Health Tracking and Biomonitoring Program was directed to collect and integrate public health data on environmental hazards, chemicals in people (biomonitoring) and chronic diseases in the state. The program is administered by the Department of Health, funded through an appropriation from the Minnesota Legislature.

The statute established both an environmental health tracking program to promote the sharing of and access to health and environmental databases and an associated program on biomonitoring. The biomonitoring section included a pilot program and, following the results of the pilot program, set forth the parameters to establish a base program within the Department of Health.

The program is advised by the Environmental Health Tracking and Biomonitoring Advisory Panel, made up of members with a background in epidemiology, public health, chronic diseases or environmental sciences. The panel makes recommendations to the department on priorities for community-based biomonitoring that will advance public health. This includes the identification of vulnerable populations or specific chemicals to study, or “other aspects of the design, implementation and evaluation of the biomonitoring system.

Minnesota Family Environmental Exposure Tracking

This study, which goes by the acronym MN FEET, measures mercury, lead, and cadmium in women and their babies in the Minneapolis and St. Paul areas. It involves pregnant women who are Asian, East African, Latina, and white, and is being done in partnership with two local health care organizations and community groups.

Women give consent to have their cord blood and urine sampled at the birth of their babies. All participants receive their test results and information on reducing exposure. Those with elevated results receive additional follow-up, including a home visit when needed.

The goal is to learn the differences in chemical levels between these groups of women and to help families best protect their children from exposure.

East Metro PFC Biomonitoring

Since 2008, the department has tracked blood levels of perfluorochemicals (PFCs) in communities east of downtown St. Paul (known as the East Metro) with known drinking water contamination. PFCs are a family of manmade chemicals that were used for many years to make products resistant to stains, grease, water and heat.

The Department of Health became concerned when, in 2005, drinking water sources in the East Metro were found polluted with PFCs. In response, the state instituted a public health intervention, including installing filtration systems for polluted public and private wells, which reduced water levels of PFCs.

Biomonitoring studies were conducted in 2008, 2010 and 2014 to determine whether the residents were accumulating PFCs. Residents selected for the study agreed to provide blood samples to determine the level of these chemicals in their bodies. Results showed that PFC levels in the blood of long-term residents who were exposed before the intervention dropped. In addition, the blood levels in residents who moved to the area after the intervention are similar to average U.S. population levels, showing that the intervention efforts were effective.

New York’s PFOA Biomonitoring Program

The New York State Department of Health performs biomonitoring, albeit without an authorizing statute. Using grant and state funds, its lab is conducting biomonitoring projects.

In the past the state has performed biomonitoring studies on environmental chemicals measured in the New York City Community Health and Nutrition Survey, and assessed uranium in workers who formerly worked at the National Lead Industries facility in the town of Colonie and in upstate residents. The state also measured methyl mercury within two Chinese communities in the state.

In 2017 the legislature did introduce Senate Bill 195 requesting a biomonitoring project on perfluorooctanoic acid (PFOA) in water. Senate Bill 195 directs the commissioner of the State Department of Health to conduct biomonitoring on the residents of Hoosick Falls, Hoosick, and Petersburgh regarding PFOA (perfluorooctanoic acid) contamination. The chemical perfluorooctanoic acid (PFOA) has been found in the water in and around these towns, which are located in an area east of Albany near the Vermont border.

PFOA is a chemical used to make carpets and clothing stain-resistant, used in fire-fighting foams and non-stick cookware such as Teflon. The chemical has been associated with kidney and testicular cancer, although there is no conclusive evidence that PFOA causes cancer in people. (The National Institutes of Health notes that “data on the human health effects of PFOA are sparse.”)

An EPA study in Hoosick Falls in 2015 found levels of PFOA above 400 ppt in the Village public drinking water supply and recommended people not drink the water from the Hoosick Falls public water supply or use it for cooking. A follow-up study did not reach the same conclusion.

This discrepancy led the Department of Health to measure PFOA in the blood of residents to determine the level of exposure from drinking water and other sources. The results will be compared against the national average of PFOA, to provide some understanding regarding whether the PFOA in drinking water is contributing to the overall level of the chemical in people.

The state is also investigating whether there are unusual rates of cancer in the area. The investigation is studying specific types of cancers as well as total concentrations of cancer diagnosed from 1995 to 2013 using data from the state cancer registry. This effort is in response to the PFOA in the public drinking water supply, using biomonitoring to determine any connection between cancer rates and PFOA.

The preliminary results from the biomonitoring study show levels of PFOA in area residents to be 10 times higher than the national average, but well below the results from occupational exposures. The state will provide residents public health information on living with PFOA.

New Hampshire’s Department of Health and Human Services Biomonitoring Program

New Hampshire is another example of a state that performs biomonitoring without statutory authority. The state Department of Health and Human Services (DHHS) received a grant in 2014 to perform two biomonitoring studies. The agency chose to conduct a targeted study on private well water users in an area of the state with a high probability of naturally occurring arsenic and a surveillance study for a panel of metals and other contaminants of concern to obtain a greater understanding of baseline levels.

Private well water users are of particular concern in the state; 46 percent of the population in New Hampshire get their water from private wells which are not subject to federal drinking water standards. Any testing or monitoring of the quality of the water is the responsibility of the well owner, not the government.

This led the state to question whether two naturally-occurring chemicals—arsenic and uranium—are present in private wells and, more importantly, whether they are affecting people who drink from these wells.

Arsenic was chosen because it is common in private wells; 20 percent of wells in the state contain the chemical. It is also undetectable by the users; it is colorless, tasteless, and has no smell. The only way to determine whether arsenic is present is to test the water.

Uranium is also common, and naturally occurring in wells in the state. The chemical is known to damage the kidneys; high exposures to uranium can lead to kidney failure and death.

Targeted Arsenic and Uranium Public Health Study

The NH public health labs launched a biomonitoring study to determine whether private well water users were being exposed to arsenic and uranium. The lab identified voluntary participants in a targeted area who agreed to have their water tested, provide a sample of their urine, and answer survey questions. For their participation, the state performed a free test of their well water and offered resources if their sample showed dangerous levels of these chemicals. This study is ongoing and all urinalysis results will be provided at the conclusion so participants can compare their results to others in the study. The program will also be offering community meetings and publishing a report with the findings.

The Targeted Arsenic and Uranium Public Health Study will not only increase the capability and capacity of the NH Public Health Labs to conduct quality biomonitoring testing, but it will also provide evidence-based information for educational campaigns and future public health initiatives.