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Endpoint:
epidemiological data
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Study period:
No data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
No individual results given for each terpene; cohort of population studied is low (only 38 individuals); only one day of investigation for exposure levels; co-exposure to many substances including wood dust, wood fumes (not measured) and probably glue vapours for some workers; exposure to aldehydes, carboxylic acids, and other strongly irritating substances released from wood were not assessed; high exposures to terpenes, and to potential strongly irritant substances (not measured), due to recirculation of dust-only recycled air indoors
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
publication
Title:
Terpene exposure and respiratory effects among workers in Swedish joinery shops
Author:
Eriksson KA, Levin JO, Sandström T, Lindström-Espeling K, Lindén G and Stjernberg NL
Year:
1997
Bibliographic source:
Scand J Work Environ Health 23(2):114-20

Materials and methods

Study type:
cross sectional study
Endpoint addressed:
acute toxicity: inhalation
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
A cross-sectional study of 38 workers was carried out in 4 joinery shops. The investigation included personal air sampling of monoterpenes, biological monitoring of metabolites of α-pinene in the workers' urine, interviews following a standardized questionnaire, and dynamic spirometry.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
not specified
Details on test material:
Name of test material (as cited in study report): Monoterpenes (alpha-pinene, beta-pinene, delta-3-carene)

Method

Type of population:
occupational
Ethical approval:
not specified
Details on study design:
METHOD OF DATA COLLECTION
- Type: Personal air sampling of monoterpenes, biological monitoring of metabolites of α-pinene in the workers' urine, interviews following a standardized questionnaire, and dynamic spirometry.
- Details: Questions regarding acute symptoms were answered by all the subjects immediately before and after a workshift. The questions pertained to headache, dizziness, tiredness, chest tightness, cough, dyspnea, irritation of the eyes, nose, or throat. The intensity of the symptoms was determined according to Borg's scale (Borg, 1982).

SETTING: Occupational (Joinery shops in northern Sweden)

STUDY POPULATION
- Total number of subjects participating in study: 38
- Sex: 28 men and 10 women
- Age: Mean age 40 (range 20-63) years
- Smoker/nonsmoker: 9 were current smokers, 9 were ex-smokers and 20 were never smokers. The ex-smokers had stopped smoking 3-41 (mean 13) years before this investigation.
- None of the workers used any kind of personal breathing protection equipment.

HEALTH EFFECTS STUDIED
- Disease(s): Acute respiratory effects were evaluated

Exposure assessment:
estimated
Details on exposure:
TYPE OF EXPOSURE:
- Four joinery shops in northern Sweden, selected as representatives of joinery shops within the area, were investigated. They all handled pinewood (soft wood) but made different finished or semifinished products. The study was performed on 2 consecutive days at each shop, and the production of wooden goods followed normal practice at each workplace. The joinery shops recirculated the indoor air to an extent of approximately 80-100 % since the outdoor temperature was approximately -10 to -5 °C when the investigations were performed.

TYPE OF EXPOSURE MEASUREMENT: Area air sampling / Personal sampling / Biomonitoring (urine) / Other: Lung function tests
- Air sampling of monoterpenes and wood dust: personal exposure to monoterpenes was assessed by diffusive sampling with charcoal as sorbent. The sampler was attached to the lapel of the worker's overalls, and the sampling period was 7-8 h. The samplers were kept at -20 °C (2-7 days) until analysis by gas chromatography, using a capillary column with a nonpolar phase. The analytical procedure according to Eriksson and Levin (1990).
- Exposure to wood dust was measured by pumped personal sampling, using the 37-mm open-face cassette method with airflow of 2 L/min, the sampling time being approximately 8 h. The filters were conditioned for 16 h at 21 ± 0.5 °C and at a relative humidity of 55 ± 2 % and were weighed before and after the sampling period.
- Biological monitoring: urine samples were collected before and immediately after the workshift. After enzymatic hydrolysis and cleaning of the samples by solid phase extraction, the amount of verbenols in the urine was determined by gas chromatography.
- Lung function tests: measurements of pulmonary function were carried out with a spirometer in the morning immediately before work was started and directly after the end of the workshift. Forced vital capacity (FVC), Forced expiratory volume during 1 s (FEV1.0) and Forced expiratory flow (FEF75) were recorded.
Statistical methods:
The Wilcoxon signed rank test for paired observations was used for analysis of the lung function readings and the questionnaires. Spearman's rank correlation test was used for correlation testing. P-value of <0.05 was considered significant.

Results and discussion

Results:
- Monoterpene concentrations: Geometric mean (GM) of the personal exposure to total terpenes during a workshift at the different joinery shops was 43 mg/m3 (9-214 mg/m3). For some of the workers in the joinery shop, the time-weighted personal exposure exceeded the present Swedish limit of 150 mg/m3 for total terpenes.
- Wood dust concentrations: The exposure to wood dust was relatively low, 0.4 mg/m3 (GM: 0.3-0.9 mg/m3) in each joinery shop, compared with the present Swedish exposure limit of 2 mg/m3.
- Biological monitoring: The concentration of verbenols in the postshift urine samples (GM = 9.12 µmol/mmol creatinine) was higher when compared with the concentration in the preshift samples (GM = 1.14 µmol/mmol creatinine).
- Lung function parameters: Neither for the whole group of 38 workers nor for the group of 20 never smokers were there any significant changes in any of the lung function parameters over a workshift. There was no correlation between exposure to terpenes during a workshift and acute changes in any of the lung function parameters studied. Workers’ preshift lung function parameters lower than the age-matched reference values (local non-smoking population): significantly low FEV1.0 and FEV/VC, even in never smokers only.
- Acute subjective symptoms: Two subjects experienced eyes, nose, and throat irritation, whereas 2 workers experienced eye irritation, 2 felt nose irritation, and 2 observed throat irritation. In general, there was no statistically significant change in any of the recorded symptoms over a workshift.
Confounding factors:
The lung function data still remained significantly low when smokers and ex-smokers were excluded, and therefore smoking was not the confounding factor.
Strengths and weaknesses:
- No individual results given for each terpene
- Cohort of population studied is low (only 38 individuals)
- Only one day of investigation for exposure levels
- Co-exposure to many substances including wood dust, wood fumes (not measured) and probably glue vapours for some workers
- Exposure to aldehydes, carboxylic acids, and other strongly irritating substances released from wood were not assessed
- High exposures to terpenes, and to potential strongly irritant substances (not measured), due to recirculation of dust-only recycled air indoors

Any other information on results incl. tables

Table 7.10.2/1: Level of exposure to terpenes, wood dust and verbenols in the different joinery shops studied

 

Type of joinery shop

Number of workers

Total terpenes (mg/m3)

Wood dust (mg/m3)

Verbenols (µmol/mmol creatinine)

GM

AM

Range

GM

AM

Range

Preshift urine

Postshift urine

GM

AM

Range

GM

AM

Range

Doors

10

19

21

9-33

0.9

1.2

0.2-4.6

0.33

0.40

0.12-0.87

5.3

5.83

2.2-8.8

Strips of wood

9

35

36

27-47

0.3a

0.3

0.1-0.5

1.15

1.23

0.65-1.97

4.4

5.13

2.6-7.7

Window frames

9

41

45

15-79

0.3

0.4

0.2-1.0

1.00

1.45

0.23-4.97

5.6

8.96

0.6-20.6

Glue-laminated wood beams

10

123

135

38-214

0.4

0.4

0.3-0.5

4.34

6.54

0.81-27.5

36.1

45.0

20.2-101

All

38

43

60

9-214

0.4

0.6

0.1-4.6

1.14

2.43

0.12-27.5

9.12

16.5

0.6-101

aNumber of samples = 7; GM: Geometric mean; AM: Arithmetic mean

 

Table 7.10.2/2: Preshift lung function parameters of 38 employees (including smokers and ex-smokers) and the 20 never smokers in the joinery shops as the percentage of reference values and the percentage of change over a workshift

 

Lung function parameters

38 workers

20 never smokers

Percentage of reference values

Percentage of change over work shift

Percentage of reference values

Percentage of change over work shift

Mean

SD

Mean

SD

Mean

SD

Mean

SD

VC

96.5

13.8a

3.8

8.7

95.0

9.9b

3.3

9.0

FVC

96.1

14.8a

1.8

10.3

95.4

10.2b

2.3

9.5

FEV1.0

89.9

15.3***

2.3

8.8

90.3

13.0**

3.3

8.6

FEV1.0/VC

92.9

10.0***

0.7

5.7

94.8

9.8*

0.2

4.3

FEF75

84.0

34.0**

2.8

22.9

90.1

39.4

7.1

25.8

 

VC =vital capacity, FVC = forced vital capacity, FEV1.0=forced vital capacity in 1 s, FEF75= forced expiratory flow rate at 75% of the FVC

*p<0.05; **p<0.01; ***p<0.001;a p = 0.07; b p = 0.06

Applicant's summary and conclusion

Conclusions:
No acute changes in lung function parameters were observed during a workshift, but the joinery shop workers had significantly lower lung function values than local referents, even when smokers and ex-smokers were excluded. Lower lung function parameters indicate obstructive lung pathology. The origin of obstruction is probably due to wood dust rather than to terpenes, as suggested by the authors.
Executive summary:

In a cross-sectional study, exposure to monoterpenes (alpha-pinene, beta-pinene and delta-3-carene) was studied in 38 workers who worked in 4 joinery shops in Northern Sweden (20/38 never smokers). The investigation included personal air sampling of monoterpenes, biological monitoring of metabolites of alpha-pinene in the workers' urine, interviews following a standardized questionnaire and dynamic spirometry.

The personal exposure to total terpenes during a workshift at the different joinery shops was 43 mg/m3 (9-214 mg/m3). The exposure to wood dust was relatively low, 0.4 mg/m3 in each joinery shop. The concentration of verbenols (metabolites of alpha-pinene) in the postshift urine samples (GM = 9.12 µmol/mmol creatinine) was higher when compared with the concentration in the preshift samples (GM = 1.14 µmol/mmol creatinine). No acute effects on forced vital capacity or forced expiratory volume during 1 s were detected. The workers had significantly reduced preshift lung function values when compared with the values of a local reference group, even when smokers and ex-smokers were excluded.

Results from the lung function tests indicate chronic rather than acute reactions in the airways. The fact that there were no major changes in lung function over a workshift indicates chronic reaction in the airways.

Co-exposure to many other substances, due to recirculation of dust-only recycled air indoors, such as wood dust (known to induce occupational asthma), wood fumes, probably glue vapours for some workers and potential strongly irritating substances released from wood (aldehydes, carboxylic acids...) was not assessed. Therefore, the lower lung function parameters observed could be due to exposure to many of these substances and most probably wood dust rather than to terpenes, as suggested by the authors.