Cadmium oxide

Epidemiological data

Administrative data

Endpoint:

epidemiological data

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 1980 to 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

All selected studies were evaluated with a check-list relating to population, exposure, endpoints, biases and confounders. Used check-list are established by Professor Philippe Hotz from the Institut für Sozial- und Präventivmedizin der Universität Zürich (EU RA 2008).

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Occupational exposure to cadmium and lung function. In: Cadmium in the Human Environment: Toxicity and Carcinogencity

Author:

Cortona G, Apostoli P, Toffoletto F, Baldasseroni A, Ghezzi I, Goggi E, Fornari S and Alessio L

Year:

1992

Bibliographic source:

Edited by GF Nordberg, RFM Herber and L Alessio. IARC. Lyon, 205-210

Materials and methods

Study type:

cross sectional study

Endpoint addressed:

repeated dose toxicity: inhalation

Principles of method if other than guideline:

Study was conducted to measure the respiratory function parameters in a population of workers with occupational exposure to cadmium compounds.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Cadmium oxide

EC Number:

215-146-2

EC Name:

Cadmium oxide

Cas Number:

1306-19-0

Molecular formula:

CdO

IUPAC Name:

oxocadmium

Details on test material:

- Name of test material (as cited in study report): CdO fumes

Method

Type of population:

occupational

Ethical approval:

confirmed and informed consent free of coercion received

Details on study design:

HYPOTHESIS TESTED (if cohort or case control study): Association between the respiratory parameters and occupational cadmium exposure

STUDY POPULATION
E: 69 men, mean age: 42.8 years
study population: part of a larger group employed at a factory producing cadmium alloys and involved in a previous research, they were exposed to cadmium fumes
control group: 79 men, manual workers selected as not occupationally exposed to cadmium fumes but of the same age and had the same smoking habits as the exposed workers

Exposure assessment:

measured

Details on exposure:

Exposure levels:
- Cd-air (µg/m3) : range: 8- 1530 (area samplers were used over the period 1975-1980, after 1980, personal samplers were used)
- biological monitoring (mean ± SD): Cd-U: 2.4 ± 1.9 µgCd/L, Cd-B: 4.3 ± 3.9 µgCd/L

Statistical methods:

regression

Results and discussion

Results:

- FVC: Forced Vital Capacity , FEV1: Forced Expiratory Volume, TLCO: Transfer Factor by the carbon monoxide method and KCO: Transfer Coefficient observed in cadmium-exposed workers were not significantly different from controls
- Mean values of RV: residual volume were moderately higher in exposed subjects as compared with those in the control group (+ 8.6%) and the difference was statistically significant. The effect on RV was greater (+ 10%) in the subgroup of workers with greater cumulative exposure to cadmium (>500 years*μg Cd/m3 ) than in the subgroup of workers with lower cumulative exposure to cadmium (<500 years*μg Cd/m3 ): +7%

Confounding factors:

Taken into account: smoking, age, height

Strengths and weaknesses:

none

Any other information on results incl. tables

- Characteristics of the workers (control and exposed)

	Controls	Cadmium-exposed workers
		total	Cumulative exposure index (µg/m^3.years)
			<500	>500
N	79	69	54	51
Smoking (cigarettes/day x years)	304.4	313.0	280.8	430.0
Cd-B (µg:100 ml)	-	0.24	0.19	0.42
Cd-U (µg/l)	-	4.3	3.1	8.5

 

- FVC, FEV1, TLCO and KCO observed in cadmium-exposed workers were not significantly different from controls:

 

Percentage (mean ± SD) in cadmium-exposed workers as compared with controls

 

Parameter	Percent of controls (%)
FVC FEV1 TLCO KCO	100.2 (± 12.1) 98.6 (± 13.8) 99.9 (± 17.5) 96.8 (±18.6)

 

- Mean values of residual volume were however moderately higher in exposed subjects as compared with those in the control group (+ 8.6%) and the difference was statistically significant.

 

Percentage (mean ± SD) in RV in two subgroups of cadmium-exposed workers as compared with controls

N workers	Cumulative exposure index (µg/m^3. years)	Variation in residual volume (RV)
69   54 15	-   <500 >500	108.6 (± 24.1)*   107.3 (± 24.2)* 110.2 (± 24.4)*

*: p<0.05

  Dose - response curve :

 

The effect on RV was greater (+ 10%) in the subgroup of workers with greater cumulative exposure to cadmium.

Applicant's summary and conclusion

Conclusions:

Authors concluded that this study suggested an important role of cadmium exposure in increasing residual volume in cadmium workers. In the subgroup with the highest cumulative exposure, smoking also increased the residual volume. No details were reported on kidney function of the exposed workers.

Executive summary:

Cortona et al. (1992) measured respiratory function parameters in 69 smoking and nonsmoking male subjects (average age 45) who were exposed to concentrations of 0.008–1.53 mg/m3 of cadmium fumes over a period of several years in a factory that produced cadmium alloys (silver-cadmium-copper). Forced Expiratory Volume (FEV), Forced Vital Capacity (FVC), Residual Volume (RV), Transfer Factor by the carbon monoxide method (TLCO), and Transfer Coefficient (KCO) were measured in these exposed individuals.

The study found that there were no significant differences in the FVC, FEV, TLCO, and KCO between the workers exposed to cadmium fumes and control (non-exposed) individuals. There was a significant increase in RV of >8% in exposed workers; this effect was notably greater in those with higher cumulative exposures to cadmium (>10%). It is uncertain how much of a factor on the increased RV was due to the tendency of smokers to develop an initial emphysematous alteration in lung tissue due to smoking.