In the third follow-up we will include both factory A and B. The mayor strength is the increase in power by addition of approximately 15 years of follow-up. We will investigate the association between exposure and mortality, cancer mortality and…
ID
Source
Brief title
Condition
- Other condition
- Lymphomas Hodgkin's disease
Synonym
Health condition
kanker en mortaliteit
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
blood serum levels of dioxins, furans and PCBs
Secondary outcome
not of influence
Background summary
In 1984, the IARC in cooperation with the NIEHS established an International
Registry of workers occupationally exposed to chlorophenoxy herbicides,
chlorophenols and their contaminants in order to assess the possible
carcinogenicity of these compounds in humans. RIVM and IRAS participated in the
IARC study with a retrospective cohort comprised of two companies producing
several chlorophenoxy herbicides.
Chlorophenoxy herbicides are widely used throughout the world in agriculture as
herbicide and as defoliants. Chlorophenoxy herbicides are structurally related
to chlorophenols that are used as raw material for the manufacture of
phenoxyacid herbicides and in wood preservation. During production
chlorophenoxyacids and chlorophenols may be contaminated with PCDDs and PCDFs.
The results from the first follow-up were inconclusive, because of the short
follow-up period resulting in a small number of cases. The results of the
second follow-up of this cohort (only factory A), showed increased risks for
cancer mortality, respiratory cancer, NHL and ischemic heart disease. However,
number of cases was too small to investigate some specific cancers.
Study objective
In the third follow-up we will include both factory A and B. The mayor strength
is the increase in power by addition of approximately 15 years of follow-up. We
will investigate the association between exposure and mortality, cancer
mortality and some specific cancers (NHL, respiratory cancer). Another main
objective is to study the shape of the exposure-response relationship. As minor
objective we will construct and/or improve exposure models, as has been done
previously. Therefore, 50 ml blood will be collected among all surviving cohort
members (both factory A and B) who have been exposed to 2,4,5-T and 2,4,5-TCP
in factory A or 2,4-D in factory B. We expect about 400 workers are willing to
donate blood. Blood will be collected at home. Blood will be used to measure
levels of PCDDs. PCDFs and PCBs in blood serum. Remaining of the blood will be
stored and later used to investigate effects of exposure to dioxins on immune
parameters, gene expression and T-lymphocyte translocations.
Study design
retrospective cohort
Study burden and risks
50 ml blood will be collected among all surviving cohort members (both factory
A and B) who have been exposed to 2,4,5-T and 2,4,5-TCP in factory A or 2,4-D
in factory B. We expect no harmfull effects of blood donation for participants.
PO Box 80178
3508 TD Utrecht
NL
PO Box 80178
3508 TD Utrecht
NL
Listed location countries
Age
Inclusion criteria
For blood collection, all living subjects from both factory A and B are included.
Exclusion criteria
Participants are excluded from blood collection if they have been diagnosed with cancer (other than non-melanome skin cancer).
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL13491.041.06 |