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Toxicological information

Epidemiological data

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Administrative data

Endpoint:
epidemiological data
Type of information:
other: This survey serves as an adjunct to a mortality study in determining if any adverse health effects were associated with occupational exposure to TDCP.
Adequacy of study:
supporting study
Study period:
1981
Reliability:
4 (not assignable)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1981

Materials and methods

Study type:
cohort study (retrospective)
Endpoint addressed:
repeated dose toxicity: inhalation
Principles of method if other than guideline:
The principal aim of the survey, based on the excess of lung cancer findings from the mortality study, was to determine if there was an excess of respiratory conditions among workers exposed to TDCP.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Type of population:
occupational
Ethical approval:
not specified
Details on study design:
The survey was based on a review and analysis of reports from physical examinations performed on a total of 124 workers. The survey population was defined as all currently employed male, full-time workers who had an occupational health program physical examination during 1981. Groups were divided according to age, with the following grouping applied: 20-29, 30-39, 40-49 and >50. The numbers of exposed: non-exposed workers in each of these groups were 19:8, 48:15, 15:4 and 11:4, respectively. The total number of exposed: non-exposed was 93:31.
A 175-item self-administered health questionnaire, a physical examination, a pulmonary function test, a chest x-ray and electrocardiogram and a spectrum of clinical and biochemical analyses were performed on the workers at the plant.
Exposure assessment:
measured
Details on exposure:
Full-shift, time weighted average (TWA) breathing zone sampling was conducted during the period December 1978 to May 1979. The report indicates that they were exposed to ‘extremely low levels of TDCP in the workplace’; TDCP levels were always near or below the limit of detection (8 ppb). Breathing zone sampling was performed between 1978 and 1979.

Results and discussion

Results:
31 % of exposed workers were non-smokers compared to 42 % of non-exposed workers. The exposed workers had lower prevalence rates than non-exposed workers for a history of respiratory conditions. The percentage of workers with impaired pulmonary function as detected by x-ray was one sixth that of non-exposed workers. Therefore, there was no increased risk of adverse respiratory effects from exposure to TDCP. There were no abnormal clinical findings in either group. There was an excess of benign neoplasms, (primarily lipomas), (5.4% Vs 0%), dermatitis (6.5 % Vs 3.2 %) and gynaecomastia (3.3 % Vs 0 %) in exposed workers when compared to non-exposed workers.
Confounding factors:
Pulmonary health of the workers is confounded by smoking.
Strengths and weaknesses:
The limitations associated with the study design included the fact that the control cohort was approximately one third the size of the exposed cohort whereas equally sized populations would have substantiated the validity of the study outcome. However, the logistics of the plant location and workforce size prevented this. In addition, some of the workers classified as non-exposed may have been exposed prior to 1975 from which time the earliest payroll records are available.

Applicant's summary and conclusion

Conclusions:
Under the working conditions presented in this study there is no increased risk of adverse respiratory effects from exposure to TDCP, no abnormal clinical findings were indicated in exposed or non-exposed workers. However, there is increased incidence in benign neoplasms, dermatitis and gynaecomastia.