Add-on Studies

Data and samples from add-on studies are made available to outside collaborators on a case-by-case basis. Information on what was collected and what may be available for new investigations can be obtained by contacting the study PI or the AHS lead investigator.

Agricultural Lung Health Study

PI: Stephanie London, NIEHS
AHS EC Contact: Dale Sandler, NIEHS

The Lung Health Study was designed to study the impact of farm exposures and genetic factors on lung function and asthma. Between 2009 and 2013, more than 3,000 AHS participants completed a home visit that included tests of lung function, collection of vacuum dust, and collection of blood and urine samples. Participants also completed a telephone interview about their history of respiratory diseases and lifetime farm exposures.

AHS Memory and Aging Study

PI: Brenda Plassman
AHS EC Contact: Dale Sandler, NIEHS

This was a project investigating whether past exposures to pesticides or other farming-related factors might affect memory later in life. Participants aged 70+ completed a telephone cognitive screening interview from 2015-2018. Those with suspected dementia based on the telephone interview then completed a comprehensive in-person dementia evaluation. During the in-home visits blood and saliva were also collected. Dementia diagnoses were assigned by an adjudication team. Details about pesticide ever-lifetime-use were collected from 1993-1997 from licensed pesticide applicators (mostly farmers), 18-25 years before the telephone interview. A total of 2,622 participants participated in the AHS Memory and Aging study.

Biomarkers of Exposure and Effect in Agriculture (BEEA)

PI: Jonathan Hofmann, NCI
AHS EC Contact: Jonathan Hofmann, NCI

The BEEA study was designed to investigate the biologic plausibility and potential mechanisms of action through which agricultural exposures influence risk of cancer and other chronic diseases. Biospecimens, including blood, urine, and buccal cells, as well as house dust samples and updated information on pesticide use and other agricultural exposures were collected from 1,681 male AHS farmer/applicators and 211 demographically similar unexposed controls enrolled between 2010-2018.

Confirmation of Self-reported Health Conditions

AHS EC Contact: Christine Parks, NIEHS

We have periodically reached out to participants who reported health conditions that were of special interest to our research team because of the possibility that farm factors may influence the chances of developing the condition. We contacted pesticide applicators and spouses who reported specific autoimmune diseases, such as rheumatoid arthritis and lupus, thyroid disease, and Parkinson’s disease to obtain additional information about diagnosis and treatment of these conditions.

Farming and Movement Evaluation Study (FAME)

PI: Caroline Tanner, The Parkinson’s Institute
AHS EC Contact: Dale Sandler, NIEHS

The Farming and Movement Evaluation (FAME) study is a case-control study of Parkinson’s Disease (PD) nested within the AHS. Home visits were conducted to perform structured neurologic examinations, draw blood, and collect dust. PD diagnoses were confirmed by movement disorder specialists. 115 confirmed PD cases and 381 controls were included in this study which was funded by an R01 grant to Dr. Tanner, supplemented with NIEHS Intramural Program funds. Participants were examined by movement disorder specialists, completed additional questionnaires, and provided samples of blood and dust from their farm.

Growth and Puberty Study

PI: Michele Marcus, Emory
AHS EC Contact: Dale Sandler, NIEHS

The Growth and Puberty Study is a pilot study to validate early markers of puberty and to evaluate the influence of agricultural exposures on pubertal growth and development involving farm families within a 100 mile radius of Des Moines, IA. Families of children aged 7-15 were invited to participate. Children were asked to provide urine and saliva samples at each of three study visits three months apart. At each visit, height, weight and fat free body mass were measured and questionnaires on Tanner staging were completed by adults and children. 48 families representing 77 children participated.

Neurobehavioral Testing Study

PI: Fred Gerr, University of Iowa
AHS EC Contact: Dale Sandler, NIEHS

This study, funded through an R01 grant to Dr. Gerr, was designed to assess the impact of chronic low level pesticide exposure on neurobehavioral function. Neurobehavioral testing was conducted on 701 farmers in the AHS from Nov 2006-March 2008. Participants were selected based on their lifetime use of organophosphate insecticides; individuals with the greatest use were oversampled to allow better representation of the high end of the exposure distribution. At the time of testing, a questionnaire was administered and blood was drawn for genetic and other analyses.

Pesticides and Sense of Smell (PASS) Study

PI: Honglei Chen
AHS EC Contact: Dale Sandler, NIEHS

Loss of sense of smell is common with aging, especially in patients with Parkinson’s and Alzheimer’s diseases. AHS participants who reported a high pesticide exposure event, such as getting a large amount of pesticides on their skin, were more likely to report a loss of sense of smell 20 years later. To follow-up on this finding, starting in 2019, AHS collaborators from Michigan State University and Duke University contacted selected participants to complete a health and farming survey and a “scratch-and-sniff” test to evaluate their sense of smell in the first phase of this study, completed by a total of 2535 participants. The second phase, including a virtual clinical assessment of neurologic health, on a smaller number of participants will be starting in 2021.