Sculpting – A Modern Menace

Abstract

Background:

Sculpting is a common occupation in India. However, there have been no studies from India on sculpting-related silicosis.

Aims:

The aims of this study were to evaluate- 1. awareness of disease related to sculpting. 2. Clinical, radiological, and physiological parameters in “sculpting workers” suffering from silicosis.

Settings and Design:

This was a retrospective evaluation of data collected during compensation visits for silicosis in workers of the sculpting industries.

Methods and Material:

The data were collected between January 2021 to April 2023. A total of 114 patients were evaluated. All patients underwent clinical evaluation including awareness about the disease, chest radiography, high-resolution computed tomography (HRCT) scan of the chest, and spirometry.

Results:

The majority of patients (109) (95%) did not use any personal protective equipment while at work and did not have any awareness regarding preventive measures. On chest radiography, small opacities (rounded or irregular) and large opacities were seen in 84 (73.7%) and 26 (22.8%) patients, respectively. The size of large opacities was significantly proportionate with duration of job (P = 0.019). HRCT chest was more sensitive compared to chest radiographs. 94 (82.4%) patients were having abnormal spirometric findings.

Conclusions:

The benefits of prevention of silica dust exposure and patient education considerably outweigh the benefits of early detection and treatment of silicosis, as there was an increase in the size of lesions with increasing duration of exposure. There should be a national health program on silicosis to protect worker’s health.

INTRODUCTION

Silicosis, a preventable disease, is still a significant public health problem, including India, caused by the long-term inhalation of inorganic dust with high concentrations (>10%) of free crystalline silica.[1] This interstitial lung disease has three clinical forms: chronic (occurs after 15–20 years of exposure), accelerated (5–10 years of exposure), and acute (a few months to 2 years of exposure).[2,3] Individual susceptibility depends on genetic and epigenetic components, which explains the different responses to similar exposure to silica dust.[4,5,6] Slow rate of removal of silica particles from the lungs causes chronic silicosis, even after occupational exposure has ceased.[7] The prevalence of silicosis in India ranges from 3.5% in ordnance factories to 54.6% in slate pencil industries.[8] At present, there is only one study from Thailand that indicates the prevalence of silicosis was 25.4% among stone carving/sculpting workers.[9] The aims of this study were to evaluate awareness of the disease related to sculpting, as well as clinical, radiological, and physiological parameters in “sculpting workers” suffering from silicosis.

METHODS AND MATERIALS

This was a retrospective analysis of data collected while evaluating the patients referred for compensation from sculpting units in western Rajasthan. This study was conducted in a tertiary care center, ESIPGIMSR, Basaidarapur, Delhi. The data were collected between January 2021 and April 2023 from patients with an exposure history of stone carving/sculpting units. The data were collected from the records (proforma) of the patients working in sculpting industries and suffering from silicosis and referred for compensation. There has been a standardized process for evaluation for silicosis since the last 15 years in this institute. This process includes a structured format in which data is collected with respect to details of the patient including an inquiry about patient education, use of mask and gloves, and methods of sculpting including wet drilling methods. It also includes the details regarding the duration and type of exposure, clinical symptoms, past history of anti-tubercular treatment (ATT), smoking history, routine blood investigations, sputum examination for acid-fast bacilli, chest radiography, spirometry, and high-resolution computed tomography (HRCT) scan of the chest, as a part of evaluation for compensation. The data regarding previous occupational history is also included in the proforma. Those patients with pulmonary diseases secondary to infections, trauma, congenital diseases, connective tissue disorders, or any other disease known to produce similar manifestations were excluded from the study. A total of 114 patients of silicosis from sculpting industries were included in the study.

Chest radiographic findings of the study population were recorded as per the standard radiographs from ILO (International Labour Office) international classification of radiographs for pneumoconiosis.[10] Accordingly, on chest radiographic findings, lung parenchymal opacities were divided based on the size as small opacities (up to 10 mm) or large opacities (>10 mm). Further, small opacities profusion category (0, 1, 2, and 3), shape and size were recorded. Based on shape and size, small opacities were further subdivided into rounded opacities; p [size: up to 1.5 mm]; q [size: 1.5–3 mm]; r [size: 3 mm to 10 mm] and irregular opacities; s [size: up to 1.5 mm]; t [size: 1.5–3 mm]; u [size: 3 mm to 10 mm]. Large opacities were labeled as Category A (size between 10 to 50 mm), Category B (size > 50 mm and up to right upper zone), and Category C (size of opacity more than right upper zone). HRCT chest findings of all the patients of the study population were recorded. Spirometry was performed as per American Thoracic Society (ATS)/European Respiratory Society guidelines at the time of evaluation for compensation.[11,12]

Statistical analysis

Data collected were compiled in MS Excel spreadsheet as a master chart. Data were presented as tables and figures. Nominal/categorical variables were expressed as frequency and percentage. They were analyzed using Chi-square test. Continuous variables were expressed as mean and standard deviation. They were analyzed using analysis of variance test for comparison between multiple groups. A P-value ≤ 0.05 was taken as statistically significant. All statistical analyses were performed using Epi info version 7.2.1.0 CDC, Atlanta, GA, USA, 2018 statistical software.

Ethical clearance

Yes ethical committee approval was taken on date 6th june 2023.

RESULTS

A total of 114 patients, ranging from 28 to 68 years of age, were included in the study. All patients were male, working in stone carving/sculpting industries using motorized instruments. None of the industries were using wet drilling methods during stone carving/sculpting. The mean age (SD) of the study population was 44.7 (8.8) years. Duration of job ranged from 2 to 46 years [mean duration (SD): 21.77 (7.9)]. None of the patients had any other significant previous occupational history or migration history. The majority of patients, 109 (95%), did not use any personal protective equipment (mask and gloves) while at work and did not have any awareness regarding preventive measures. The mean BMI (SD) of the study population was 18.04 (4.17) kg/m². Thirty-two (28.1%) patients had a history of smoking, and 27 (23.7%) patients had taken ATT in the past. Shortness of breath was the most common symptom reported by patients (85.1%), followed by cough (70.2%), weight loss (15.8%), and fever (6.1%). The majority of the patients had more than one symptom. The baseline characteristics of the study population are shown in Table 1.

Table 1.

Baseline Characteristics of Study Population (n=114)

Baseline characteristics		Mean ±SD
Age (years)		44.7±8.8
Duration of job (years)		21.77±7.9
BMI (Kg/m2)		18.04±4.17
Smokers		32 (28.1%)
Past history of ATT		27 (23.7%)
Cough		80 (70.2%)
Shortness of breath		97 (85.1%)
Fever		7 (6.1%)
Weight loss		18 (15.8%)

Chest radiographic (postero-anterior view) findings of all the patients (114) were recorded as per the standard radiographs of ILO, which are shown in Table 2. The technical quality of all the chest radiographs was 1 (as per ILO, 1 means good). On chest radiography, small opacities (rounded or irregular) were seen in 84 (73.7%) patients. The profusion categories of small opacities were 0 in 2 patients (1.7%), 1 in 20 (17.5%), 2 in 33 (28.9%) and 3 in 31 (27.2%) patients. The predominant small opacities were rounded opacities seen in 76 (66.7%) patients [p-type: 21.9%, q-type: 19.3%, r-type: 25.4%] whereas irregular opacities (s, t, u) were seen in 8 (7.0%) patients. Thirty patients (26.3%) did not have any small opacities. Large opacities were noted in 26 (22.8%) patients [category A: 9.6%, category B: 9.6%, category C: 3.5%]. Eighty-eight patients (77.2%) did not have any large opacities. A correlation was observed between the duration of job and opacities in the chest radiograph [Table 3]. Small opacities profusion and size increased with increasing duration of the job, and the difference was, however, not found to be statistically significant [P = 0.137, P = 0.410 respectively]. Among large opacities, category C opacities were seen only in patients with a duration of job >20 years. Category B opacities were also more common among those with duration of job >20 years (57.1%) as compared to those with duration of job 10-20 years (33.3%) and none in those with duration of job <10 years. Overall, the size of large opacities was found to be significantly larger with increasing job duration [P = 0.019].

Table 2.

Chest Radiographic findings as per ILO Standard and Spirometry findings of Study Population

Total number of patients (n)		114
Technical quality – 1		114 (100%)
Small opacities		84 (73.7%)
Profusion category
0     1     2     3		2 (1.7%) 20 (17.5%) 33 (28.9%) 31 (27.2%)
Small opacities – Shape and size		26 (22.8%)
P/p     q/q     r/r     s/t/u		25 (21.9%) 22 (19.3%) 29 (25.4%) 8 (7.0%)
Large opacities
NO     A     B     C		88 (77.2%) 11 (9.6%) 11 (9.6%) 4 (3.5%)
Spirometry findings
Normal     Obstructive     Restrictive     Mixed		20 (17.5%) 7 (6.1%) 74 (64.9%) 13 (11.4%)

Table 3.

Correlation of Duration of job with Chest X-rays Opacities, Spirometry and BMI

	Duration of job (in years)			P
	≤10 years	11–20 years	>20 years
Small opacity profusion	(n=6)	(n=36)	(n=44)
0	1 (16.7%)	1 (2.8%)	0	0.137
1	2 (33.3%)	7 (19.4%)	11 (25%)
2	2 (33.3%)	17 (47.2%)	14 (31.8%)
3	1 (16.7%)	11 (30.6%)	19 (43.2%)
Small opacities Shape and size	(n=5)	(n=35)	(n=44)
p/p	2 (40%)	10 (28.6%)	13 (29.5%)	0.410
q/q	3 (60%)	9 (25.7%)	10 (22.7%)
r/r	0	13 (37.1%)	16 (36.4%)
Large opacities	(n=3)	(n=9)	(n=14)
A	3 (100%)	6 (66.7%)	2 (14.3%)	0.019 (S)
B	0	3 (33.3%)	8 (57.1%)
C	0	0	4 (28.6%)
Spirometry findings	(n=9)	(n=45)	(n=60)
Normal	4 (44.4%)	9 (20%)	7 (11.7%)	0.267
Obstructive	1 (11.1%)	3 (6.7%)	3 (5%)
Restrictive	3 (33.3%)	29 (64.4%)	42 (70%)
Mixed	1 (11.1%)	4 (8.9%)	8 (13.3%)
BMI (mean±SD)	14.61±5.35	14.57±3.23	13.49±5.56	0.700
FEV1 (mean±SD)	1.61±0.69	1.54±0.58	1.38±0.49	0.218
FVC (mean±SD)	2.11±1.02	1.88±0.69	1.72±0.61	0.193
FEV1/FVC (mean±SD)	79.33±15.02	84.06±12.34	82.29±13.08	0.560

HRCT chest findings of all the patients (114) are shown in Table 4. The predominant lesions seen were rounded opacities in 85.1% of patients, Mediastinal lymphadenopathy in 80.7%, large opacities in 26.3%, and linear opacities in 20.2% of patients. Other important findings were pleural thickening (18.4%), bronchiectasis (12.3%), emphysema (11.4%), cavity (7.9%), egg cell calcification (7%), tree in bud opacities (3.5%), mosaic pattern (2.6%), consolidation (2.6%), pleural effusion (1.8%), combined pulmonary fibrosis, and emphysema (1.8%). Lung mass and pneumothorax were seen only in one (0.9%) patient each. Overall, parenchymal diseases were present in 73.7%, pleural involvement in 8.8%, and airway diseases in 2.6% of patients, whereas 14.9% of patients had overlapping diseases, as shown in Figure 1.

Table 4.

High-Resolution Computed Tomography Thorax findings of Study Population (n=114)

HRCT Chest findings		n (%)
Centrilobular emphysema		13 (11.4%)
Mediastinal lymphadenopathy		92 (80.7%)
Large opacities		30 (26.3%)
Cavity		9 (7.9%)
Pneumothorax		1 (0.9%)
Consolidation		3 (2.6%)
Bronchiectasis		14 (12.3%)
Egg cell calcification		8 (7%)
Rounded opacities		97 (85.1%)
Linear opacities		23 (20.2%)
Pleural thickening		21 (18.4%)
Pleural effusion		2 (1.8%)
Lung mass		1 (0.9%)
CPFE*		2 (1.8%)
Tree in bud opacities		4 (3.5%)
Mosaic pattern		3 (2.6%)

*Indicates Combined pulmonary fibrosis and emphysema

Figure 1.

High-Resolution Computed Tomography Thorax findings of Study Population (N = 114), Showing Parenchymal, Pleural, Airway Diseases, and their Overlapping findings

Small opacities were seen in 84 (73.7%) chest radiographs and 97 (85.1%) HRCT chest. Similarly, large opacities were seen in 26 (22.8%) chest radiographs and 30 (26.3%) HRCT chest. Thus, our study concluded that HRCT chest was more sensitive than chest radiography for the detection of parenchymal opacities.

Mean BMI of the study population decreased with increasing duration of job, which was not found to be statistically significant (P = 0.700), as shown in Table 3. Spirometric findings of all the patients (114) were noted, and their correlation with duration of job was observed [Tables 2 and 3]. Only 20 (17.5%) patients had spirometric findings within the normal limits, whereas 94 (82.4%) patients had abnormal findings, which included restrictive, obstructive, or mixed patterns. These were as follows: 74 (64.9%) patients had restrictive patterns, 13 (11.4%) were mixed, and only 7 (6.1%) had pure obstructive patterns. Mean forced vital capacity (FVC) and mean forced expiratory volume in 1 second (FEV1) were lower in patients with longer duration of job; the difference was, however, not found to be statistically significant [P = 0.193, P = 0.218 respectively].

DISCUSSION

Shaping of stone by controlled stone removal is called stone carving/sculpting. There is only one study in the available literature that shows the prevalence of silicosis in stone carving processes.[9] This is the first study from India that involves stone carving/sculpting-related silicosis in workers using motorized equipment. The clinical spectrum of diseases related to silica exposure can range from asymptomatic conditions to acute silicosis, tuberculosis (TB), chronic obstructive pulmonary disease, chronic bronchitis, lung cancer, and idiopathic pulmonary fibrosis. Apart from pulmonary diseases, it can also lead to systemic involvement, like kidney damage, autoimmune diseases, sarcoidosis, etc.[13,14] In our study, all the patients had lung involvement. None of these patients had systemic disease.

Exposure history of silica, chest radiography, HRCT chest, and spirometry are the major methods for evaluation of silicosis and other silica-related diseases. In our study on chest radiography as per the ILO classification system, small opacities were seen in 73.7% of patients. Predominant small opacities were rounded opacities seen in 66.7%, whereas irregular opacities were seen in 7.0% of patients. Large opacities were noted in 22.8% of patients. These findings were comparable to a study performed by S.M. Jain et al.[15] We also showed that there was an overall increase in the size of small as well as large opacities with increasing duration of exposure. But increase in the size of opacities was statistically significant for only larger opacities (P = 0.019) and not for the small opacities (P = 0.410), similar to a study performed by Hughes et al.[16]

We performed chest radiography and HRCT on all the patients. We observed that the HRCT chest was more sensitive than chest radiography, which was comparable to previous studies.[17,18] Although HRCT chest is more specific and sensitive than chest radiograph, chest radiographic examination based on the ILO classification system still holds a significant role in the evaluation of workers exposed to silica, since it is an inexpensive and the dose of radiation is low in chest radiography. Artificial intelligence (AI)-enabled radiology tools stand to fill the need for regulatory compliance in pneumoconiosis screening, while offering a labor-saving solution to physician workflow issues and also reducing inter-observer variations.[19,20] For evaluation of silicosis, lung biopsy should be avoided unless absolutely necessary for another reason because surgical manipulation is associated with unfavorable outcomes.[21]

In relation to pulmonary function, we observed that ventilatory defects (obstructive, restrictive, or mixed) were quite common, being diagnosed in 82.4% of the cases. In silicosis, airflow limitation is caused by many factors, such as airway narrowing secondary to peribronchiolar fibrosis, mediastinal lymph node enlargement, and centrilobular emphysema.[22,23] Our study observed that the decline in pulmonary function increased with increasing duration of exposure to silica dust, which was comparable to many other studies.[24,25,26]

There is no cure for silicosis, and prevention is the only option. Prevention of silica dust exposure and patient education are more important than early detection and treatment of silicosis. Currently, various preventive measures, including ventilation systems, wet drilling methods, dust control equipment, and personal protective equipment such as masks, goggles, hand gloves, and respirators, are recommended for decreasing workers’ exposure to silica dust.[6,27] There should be no compromise in enforcing the important provisions of the Factories Act 1948, the Mines Act 1952, even in the smaller units.[28,29] So, though the regulations are in place, the enforcement needs to be exercised strictly. Silicosis is recognized as a notifiable and compensable disease under these acts. It still remains underdiagnosed and underreported in India, as evidenced by the recent annual report of the Ministry of Labour and Employment.[30] This notification helps in getting compensation to the workers. There is a large NGO (non-governmental organization) force that helps compensate. However, punitive measures, monetarily or otherwise, should be in place for preventive measures too. A “National Silicosis Control Program” should encompass health promotion, personal protection, preventive measures, diagnostic criteria, symptomatic management, and rehabilitation. Until such a program is established, silicosis control activities should be integrated with TB elimination efforts.[31]

Strengths of study

No such study is available in India which involves the study of silicosis in stone carving/sculpting workers. Carving in the ancient period was performed by chisels and hammers, but nowadays, the use of motorized instruments leads to excessive dust generation in a short period of time, which causes massive exposure in the breathing zone of artisans. This study was performed on these artisans.

Limitations of study

This was a retrospective study. Prospective studies to demonstrate the real-time suffering of these workers and interventional studies to prevent the menace of silicosis/dust-induced lung diseases in the near future are required.

CONCLUSIONS

Silicosis is not a curable but preventable disease. The benefits of prevention of silica dust exposure and patient education considerably outweigh the benefits of early detection and treatment of silicosis. There should be a national health program on silicosis to protect workers’ health. Until such a program is established, silicosis control activities should be integrated with TB elimination efforts.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.