Registration Dossier

Administrative data

Endpoint:
epidemiological data
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1973

Materials and methods

Study type:
cohort study (retrospective)
Endpoint addressed:
basic toxicokinetics
respiratory irritation
repeated dose toxicity: inhalation
carcinogenicity
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Method other: Work place exposure – potash mining
Method: Eight companies from the potash and milling industry located near Carlsbad/USA cooperated in the investigation. Job classification was assessed as to whether it involved surface or underground activity, or both, and the men were divided into two categories after excluding men with less than one year experience in the potash industry or with more than one year in both surface and underground work (1058 men); 1) men with one year or more of underground potash work, and less than one year of surface potash work between 1940-1967 (2743 men), and 2) men who had one year or more of surface potash work, and less than one year underground potash work between 1940-1967 (1143 men).
Comparison was made between the observed risk of dying among the study cohort, with that expected according to age, sex, race, calendar time, and cause specific mortality rates for the general population of the United States.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report):: Potash (potassium oxide)

Method

Type of population:
occupational
Ethical approval:
not specified
Details on study design:
Eight companies from the potash and milling industry located near Carlsbad/USA cooperated in the investigation. Job classification was assessed as to whether it involved surface or underground activity, or both, and the men were divided into two categories after excluding men with less than one year experience in the potash industry or with more than one year in both surface and underground work (1058 men); 1) men with one year or more of underground potash work, and less than one year of surface potash work between 1940-1967 (2743 men), and 2) men who had one year or more of surface potash work, and less than one year underground potash work between 1940-1967 (1143 men).
Comparison was made between the observed risk of dying among the study cohort, with that expected according to age, sex, race, calendar time, and cause specific mortality rates for the general population of the United States.
Exposure assessment:
estimated

Results and discussion

Results:
The field studies conducted failed to disclose any evidence of predisposition of underground miners to any of the diseases evaluated,
including lung cancer. Secondly, the study concluded there is no reason to believe that the underground environment increases respiratory
diseases when pneumoconiosis producing dust or radon decay products are absent or present in only minute amounts.
Exposure to dust, i.e. sodium and potassium salts, commonly encountered in the potash industry did not influence mortality due to heart disease or cerebrovascular accidents. A deficit of death from cancers other than respiratory among the surface workers could not be explained.

Applicant's summary and conclusion

Conclusions:
The field studies conducted failed to disclose any evidence of predisposition of underground miners to any of the diseases evaluated,
including lung cancer. Secondly, the study concluded there is no reason to believe that the underground environment increases respiratory
diseases when pneumoconiosis producing dust or radon decay products are absent or present in only minute amounts.
Exposure to dust, i.e. sodium and potassium salts, commonly encountered in the potash industry did not influence mortality due to heart disease or cerebrovascular accidents. A deficit of death from cancers other than respiratory among the surface workers could not be explained.