The Continued Growth in the Number of Workers Potentially Exposed to Silica Dust in India – A Recent Estimate

Abstract

Using the Periodic Labour Force Survey data, we estimate the number of workers potentially exposed to silica dust in India and its distribution in various industries and occupations. We also indicate the gaps in our knowledge on the risk of developing silicosis, the burden of silicosis in the population, and the role of the occupational health community in documenting and addressing this challenge.

BACKGROUND

The readers of this journal need no introduction to silicosis as an occupational health challenge. But by seeing it as a developmental challenge, we are confronted with issues of marginalization, injustice, and the devaluation of human life and dignity.[1] About a year ago, we interviewed Dr. Prakash Tyagi, who heads GRAVIS (Gramin Vikas Vigyan Samiti), a non-governmental organization based in Jodhpur, Rajasthan.[2] He spoke about the experiences of stone workers in Rajasthan, the challenges with accessing healthcare and relief, the involvement of human rights commissions, and the recent institution of a state policy for occupational lung diseases. Activists have been campaigning for justice for silicosis-affected persons since many years, and the Supreme Court has intervened in many situations.[3]

Elsewhere, in California in the US, changes in demand for stone (specifically, engineered stone) for countertops have led to hundreds of silicosis cases over the past few years.[4] The situation of workers there mirrors what we see in India: migrant workers (from Latin American countries) who are in a precarious situation, unregulated small workshops, and resistance from the workshop owners to implement protective measures due to expenses. Emergency rules were put in place to protect these workers, many of whom are waiting for lung transplants. These reports shed light on the persistence and periodic resurgence of these challenges.

My immediate question after listening to Dr. Tyagi’s talk was whether the prevalence of silicosis is increasing in India. It is a preventable disease, and also one that is life-threatening, often leading to death at a young age. A high prevalence adds to the case of something being a matter of public health importance.

Exposure to silica dust increases the risk of various conditions such as silicosis, tuberculosis, and cancer. Data from the Global Burden of Disease portal estimates that, for 2023, the total deaths in India due to silica dust exposure through chronic respiratory disease were 576, and due to neoplasms were 3890 (a total of 4466 deaths). No estimates were provided for deaths due to tuberculosis and other impacts of silica dust exposure,[5] whereas a recent study showed much lower survival among tuberculosis patients who concurrently have silicosis as compared to those without it.[6]

There are various jobs in India where workers are exposed to silica dust, including stone quarries, mining, construction, and glass and jewelry work. Different jobs have differing exposure profiles for workers – with some being more severe than others. Overall, the potential for exposure to silica dust may have increased in the country because of the rapid urbanization we are witnessing. For instance, there would be increased demand for stone for construction projects and also energy in urban areas (and thereby coal mining).

While this nuanced exposure information is not available for the Indian context, it would still be useful to estimate the number of workers who may be exposed to silica dust in various industries in India. Based on our knowledge, the only survey that captures adequate and representative details of people’s occupations in India is the Periodic Labour Force Survey (PLFS), which is conducted regularly across the country. While no health information is collected, the data from the survey could be used to estimate the number of workers employed in specific conditions, such as those potentially being exposed to silica dust. We used this data to estimate the number of workers who may be exposed to silica dust in occupational contexts in India.

WHO AND HOW MANY ARE EXPOSED?

We used a combination of the occupational and industry codes provided in the PLFS to shortlist the individuals in the dataset who may have been exposed to silica dust (the detailed list of codes can be provided over email). Table 1 shows that the total number of potentially exposed workers was estimated to be almost 56 million, with around 54 million in the construction and civil engineering sectors and 2 million in other industries such as mining, quarrying and manufacture of mineral products. The occupational group with the highest number of exposed was “mining and construction laborers,” with over 46 million persons.

Table 1.

Summarized data from the shortlisted NCO* groups (columns) and NIC^† subclasses (rows) for 2024

Relevant sectors	Building frames and related trades workers	Handicraft workers	Mining and construction laborers	Mining and mineral processing plant operators	Other stationary plant and machine operators	Grand total (percentage of total exposed workers)
Civil engineering	5553		860928	22162		888,643 (1.6)
Construction of buildings	8466149		44159913	15571	4684	52,646,317 (94.1)
Manufacture of other non-metallic mineral products	236152	552391	344904	18189	155686	1,307,322 (2.3)
Mining of coal and lignite			209135	37409		246,544 (0.4)
Mining of metal ores		3673	95297	8696	8279	115,945 (0.2)
Other manufacturing		243155				243,155 (0.4)
Other mining and quarrying	26125	9230	257949	33921		327,225 (0.6)
Specialized construction activities	7455		154780	7660	2797	172,692 (0.3)
Grand Total (percentage of total exposed workers)	8,741,434 (15.6)	808,449 (1.4)	46,082,906 (82.4)	143,608 (0.3)	171,446 (0.3)	55,947,843

*NCO=National Classification of Occupations, ^†NIC=National Industrial Classification (Source: author)

As we had suspected, our estimates indicated that the number of people engaged in occupational environments with potential exposure to silica dust had increased substantially between 2018 and 2024, with the increase primarily being in the construction sector [see Table 2]. Overall, this is a sizable proportion of India’s population that is engaged in work exposing people to silica dust (approximately 4%).

Table 2.

Estimates of the number and proportion of workers in industries (and occupations) with potential silica dust exposure for the years 2018 and 2024

Industry division	2018 estimated population* (proportion†)	2024 estimated population* (proportion†)	Difference in population (2024-2018)	Percentage change from 2018 to 2024
Construction of buildings	25,582,748 (1.94)	52,646,318 (3.76)	27,063,570	105.8
Civil engineering	1,366,631 (0.1)	1,307,325 (0.09)	-59,306	-4.3
Manufacture of other non-metallic mineral products	561,006 (0.04)	888,644 (0.06)	327,638	58.4
Other mining and quarrying	546,840 (0.04)	327,227 (0.02)	-219,613	-40.2
Specialized construction activities	510,614 (0.04)	246,545 (0.02)	-264,069	-51.7
Mining of coal and lignite	192,007 (0.01)	243,155 (0.02)	51,148	26.6
Other manufacturing	170,905 (0.01)	172,693 (0.01)	1,788	1.0
Mining of metal ores	123,657 (0.01)	115,946 (0.01)	-7,711	-6.2
Total	29,054,408 (2.2)	55,947,853 (3.99)	26,893,445	92.6

*Weighted count after adjusting with population projection only for the selected sub-classes of the industry divisions (not all the subclasses within each industry division). ^†Proportion of the projected total population of India for that year. (Source:[7])

TRENDS DIFFER ACROSS STATES

State-wise analysis can provide further insights into how things are changing in these sectors. We can also estimate the total number of workers in each of these occupations and industries in each state. For instance, in the construction sector, we see a 961% increase in the workforce between 2018 and 2024 in Arunachal Pradesh (the greatest increase for any state in that period), whereas 7.25% of the population is involved in construction in Tripura (the highest proportion for any state) and 8.4 million people are involved in construction in Uttar Pradesh (the most for any state in 2024) [see Table 3]. Each tells us something about the significance of the challenge in each of those contexts, with implications for the policy and programmatic attention needed. Of course, not all workers in the construction industry are equally exposed to silica dust. Specific activities that involve cutting, drilling, concrete mixing, sandblasting, and tunneling operations are reported as those with higher exposure,[8] but without further studies in India, it is difficult to rule out exposure to silica dust among any other type of construction workers.

Table 3.

Growth in the number of construction workers in select states between 2018 and 2024

State	Number in 2024	Number in 2018	Difference between 2024 and 2018	Growth from 2018 to 2024 (%)
Arunachal Pradesh	29452	2774	26678	961.7
Karnataka	2001682	1382656	619026	44.8
Punjab	957061	996519	-39458	-4.0
Tripura	279238	119102	160136	134.5
Uttar Pradesh	8423103	6323831	2099272	33.2

(Source: author)

GENDER, SILICA DUST EXPOSURE, AND CARE WORK

Most of the exposed persons are men (over 90%): the overall proportion of women workers in the relevant occupations with silica dust exposure was 9.4% in 2018 and 7.3% in 2024. But we see a great degree of variation in women’s participation across relevant industries (see Figure 1), for instance, the “Other manufacturing” division includes persons working in jewelry-making, where the female workforce is relatively higher (30.3% and 49.4%, respectively, in 2018 and 2024).

Figure 1.

Proportion of women workers with potential exposure to silica dust in 2018 and 2024 by industry division

The other side of the gender dimension of this challenge is the care work that spouses need to put in after the husband or son is diagnosed with silicosis. With the male member unable to provide for the household due to the debilitating condition, and due to mounting healthcare costs, assets are sold, and there is a struggle to receive financial compensation.[9]

IMPLICATIONS FOR ACTION

Exposure to silica dust often happens in informal and unregulated workplaces. Based on the current situation, there is a need to strengthen both prevention and access to healthcare. The Rajasthan Policy on Pneumoconiosis[10] is instructive on the range and nature of interventions needed to address this. Not only has the policy described the need to identify all hazardous workplaces irrespective of size, but it also provides clear directions on the need to regulate and innovate the equipment, technology, and workplaces to protect worker safety. This is in addition to the need for capacity and equipment to diagnose and care for those affected. Importantly, the policy mentions the need for social accountability through transparency and dialogue with the public on the actions being taken. There should be closer documentation of how the policy is being implemented, whether the interventions are proving to be effective in reducing the number of cases, and improving access to care for those affected. Those struggling with this incurable disease (and their families) should not have to struggle to access care and support. In addition, other states should also consider adopting this policy, especially those identified with a higher number and proportion of workers in these jobs.

Keeping in mind that the government itself is involved in large-scale infrastructure, mining, and construction projects, the government should show the way on how workers should be protected as part of their own projects—and these efforts should be documented and studied to better inform the various sectors where silica dust exposure is expected.

It is not likely that the demand for stone will reduce, and this is besides the general increase in construction and infrastructure projects. Hence, it is very important to work toward reducing exposure to dust in these and other relevant occupational settings. This should move alongside documenting the health challenges of the workers, monitoring workplace dust levels, and systematically studying the effectiveness of the preventive and care measures. This work will benefit from the involvement of preventive medicine physicians, occupational hygienists, and social scientists – to document, analyze, and recommend what measures work well in which settings. This is an opportunity to prevent a deadly disease among the most vulnerable groups in the population. A strong response from the occupational health community can make that happen.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.