Organochlorine Pesticide Exposure in Residents Near Lake Apopka

September 17, 2019 updated by: University of Florida

In the Lake Apopka, Florida area for over 50 years starting in the 1940s, organochlorine pesticides (OCPs) including 4,4'-dichlorodiphenyltrichloroethane (DDT), dieldrin, chlordane, toxaphene and more recently methoxychlor were sprayed on farmlands in order to control pests and to improve crop harvests. For most of those years, the farmworkers were exposed to the pesticides as part of their work. Because of their lipophilic (fat soluble) nature, these organochlorine pesticides (OCPs) are readily taken up into the body and not readily eliminated. Therefore, they can be detected in exposed individuals for many years after the exposure. There is some evidence that certain OCPs can cause or exacerbate medical problems in sensitive individuals. For example, exposure to some OCPs has been associated with development of Parkinsonism. Exposure to other OCPs has been associated with development of lupus erythematosus, an auto-immune disease. Other adverse effects of exposure to OCPs are endocrine disruption because some OCPs mimic estrogens and others mimic androgens, or may have mixed interactions with steroid receptors.

In this research study the investigators aim is to test the blood from former farmworkers during the 1940s through the late 1970s who reside in the Lake Apopka area for OCPs and for the auto-antibodies. In addition, questionnaires will provide insight on their health status and health concerns.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

In this research study, a onetime blood test will be collected from former farmworkers during the 1940s through the late 1970s who reside in the Lake Apopka area for OCPs and for the auto-antibodies. In addition, questionnaires will provide insight on their health status and health concerns.

The investigators will collect existing data from the National Health and Nutrition Examination Survey (NHANES) which has monitored the pesticide exposure (with the exception of toxaphene) of people older than 8 years, so there is information on the range of concentrations of these chemicals in the blood of Americans. This data will be use as the control group for comparison with the values found for OCP concentrations.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
20

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Florida
      • Gainesville, Florida, United States, 32611
        • University of Florida

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

21 years to 90 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Probability Sample

Study Population

Participants for this study will be recruited from the Florida Farmworker Association of Florida, Lake Apopka, FL.

Description

Inclusion Criteria:

  • Persons who worked on farms near lake Apopka, Florida up to 1998.
  • Preference will be given to those who worked on the farms for over 10 years.

Exclusion Criteria:

  • Persons who did not work on farms near Lake Apopka, Florida up to 1998.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Lake Apopka Farmworkers
This group will have a onetime blood collection and questionnaires regarding health status and health concerns.
Other: Blood Collection
Onetime blood collection.
Existing Data Group
The investigators will collect existing data from the National Health and Nutrition Examination Survey (NHANES) for the range of concentrations of these chemicals in the blood of Americans.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Blood levels of organochlorine pesticides will be compared between the groups
Time Frame: Day 1
Blood collected will be analyzed for DDT, dieldrin, chlordane, methoxychlor and the metabolites of DDT and methoxychlor. The data will be compared between the groups.
Day 1

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Level of auto-antibodies will be recorded
Time Frame: Day 1
Blood collected will be analyzed for measurement of auto-antibodies
Day 1

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Florida

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Margaret O. James, Ph.D., University of Florida

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2015

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 1, 2016

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 1, 2016

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 18, 2015

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 19, 2015

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 21, 2015

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 19, 2019

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 17, 2019

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2019

More Information

Terms related to this study

Keywords

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • IRB201401073

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Age and years worked on farms will be shared

IPD Sharing Time Frame

Will be reported in publication, in preparation.

IPD Sharing Access Criteria

upon request

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • ICF

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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