Studying Blood Toxicity in Workers Exposed to Formaldehyde

November 12, 2020 updated by: National Cancer Institute (NCI)

A Cross-Sectional Study of Hematotoxicity in Workers Exposed to Formaldehyde

Background:

- Formaldehyde has many uses in industry and medicine. However, exposure to formaldehyde has been associated with increased risk for myeloid leukemia. There are still questions about how the chemical reacts with bone marrow to increase this cancer risk. Some smaller studies have looked at how it affects stem cells, which are found in bone marrow. Researchers want to develop a much larger study of workers in China. The study will look at different levels of formaldehyde exposure. It will focus on how the chemical affects the blood cells and bone marrow.

Objectives:

- To study the effects of formaldehyde exposure on blood cells and bone marrow.

Eligibility:

- Individuals between 18 and 60 years of age who work in selected factories in Guangdong Province, China.

Design:

  • Participants will be screened with a physical exam and medical history. They will also be screened with a work history. Those who have been exposed to benzene, butadiene, styrene, or radiation will not be included.
  • Participants will be studied based on their regular formaldehyde exposure level. One-third will be those exposed to more than 1 part per million (ppm) of the chemical. One-third will be those exposed to 0.3 to 1 ppm. A control group will have no exposure to formaldehyde or any other known toxic chemical.
  • Participants will provide blood and cheek swab samples. They will also answer questions about their work habits.
  • To look at chemical exposure levels, participants will wear a small monitor to work on 3 different days. They may provide additional blood and cell samples as directed.
  • No treatment will be provided as part of this study.

Study Overview

Status

Completed

Detailed Description

Research in industrial workers and professionals exposed to formaldehyde suggests that occupational exposure to this important chemical is associated with increased risk for myeloid leukemia. However, there is still uncertainty about the biologic plausibility of the association because of questions regarding the ability of formaldehyde, which is extremely reactive, to directly or indirectly cause toxicity to the bone marrow. There have been several relatively small studies of the impact of occupational formaldehyde exposure on peripheral blood cells that found some evidence that peripheral blood cells of the myeloid lineage (i.e., granulocytes, platelets) were significantly decreased in exposed workers. We propose to follow-up these findings in a relatively large study population in China. We will study hematologic parameters in 240 higher exposed workers (>1 ppm), 240 workers exposed to lower levels of formaldehyde (0.3 to 1 ppm), and a group of 240 unexposed controls frequency-matched to exposed workers. This study will make an important contribution to our understanding of the leukemogenic potential of formaldehyde, which has important public health and regulatory implications.

Study Type

Observational

Enrollment (Actual)

708

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

      • Guangzhour, China
        • Guangdong National Poison Control Center (NPCC)

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

Ages Eligible for Study

18 years to 60 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

We will identify formaldehyde-exposed manufacturing workers during the cross-sectional study. The exposed workers have to have held the same job for at least 3 months in the same factory. We expect that the age and sex distribution will be similar in the lower and higher exposed workers. We will enroll controls without previous occupational exposure to formaldehyde or any other genotoxic, hematotoxic or immunotoxic chemicals in two factories that manufacture clothes located in the same@@@geographic area as the utensil producing factories.

Description

  • INCLUSION CRITERIA:
  • The eligible age range for the study will be 18 to 60 years old

EXCLUSION CRITERIA:

Exclusion criteria for both formaldehyde-exposed and control workers will be:

- A history of cancer, chemotherapy, and/or radiotherapy, as well as previous or current occupational exposure to benzene, butadiene, styrene and radiation.

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

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Hematotoxicity Change
Time Frame: 2012-2024
Complete blood counts
2012-2024
Immune Function
Time Frame: 2012- 2024
immune biomarkers
2012- 2024

Collaborators and Investigators

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

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.

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 (Actual)

February 9, 2012

Primary Completion (Actual)

May 30, 2013

Study Completion (Actual)

November 12, 2020

Study Registration Dates

First Submitted

March 6, 2012

First Submitted That Met QC Criteria

March 6, 2012

First Posted (Estimate)

March 8, 2012

Study Record Updates

Last Update Posted (Actual)

November 16, 2020

Last Update Submitted That Met QC Criteria

November 12, 2020

Last Verified

November 1, 2020

More Information

Terms related to this study

Other Study ID Numbers

  • 999912055
  • 12-C-N055

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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