Silicosis in India: Defining the problem and developing solutions | By Dr. S.K Jindal | Jindal Chest Clinic

Silicosis is a lung disease caused by inhaling small particles of silica, a common mineral found in sand, quartz, and rock, primarily affecting workers in construction and mining industries. For more information, please contact us: 9779030507.

1. Silicosis in India
Defining the Problem and Developing Solutions
Dr. S. K. Jindal
(Ex-Professor and Head, Department of PulmMed, Postgraduate Insttof Med Edu
& Research, Chandigarh, India)
Medical Director, Jindal Clinics, Chandigarh, India

2. •Rock cutting and stone carving to build temples
since B.C. era
•In India, occupational lung diseases mentioned in ancient texts 4
th
century AD

3. High prevalence of silicosis among
stone-carvers in Brazil
Antaoet al, Am J IndMed, 2004
•Artisanscarvingsouvenirs(42)
•Silicosis(53.7%)
•Associatedwithexposureto
highlevelsofsilicadust

4. Diseases associated with exposure
to Silica dust in India
•Silicosis
•Mycobacterialinfection
•Occupationalasthma
•Chronicobstructivepulmonarydisease
•Mineraldustinducedsmallairwaydisease
•Lungcancer
•Immune–RelatedDisease
–PSS,RA,CRD,SLE

5. Population at risk for silicosis in India
Industry No. of workers
Manufacturing of basic metals &
alloys (Steel, Copper, Ferro-alloys)
6,29,000
Mines and Quarries 17,00,000
Manufacturing of products
(Refractory, Glass, Mica, etc)
6,71,000
Construction sector 70,00,000
Total 1Crore
SELF-EMPLOYED & UNORGANISED SECTOR WORKERS NOT INCLUDED

6. Silicosis
Most prevalent chronic fibrotic lung disease caused by inhalation,
retention and reaction to large amounts of silica dust (SiO2)

7. Prevalence of Silicosis
•C.KrishnaswamiRaowasfirsttoconfirmcasesofsilicosisinIndiain1934
•FirstSilicosisSurveyinKolarGoldFields(1940-1946)byCaplan(etal)
•Of7653workersexaminedinKolarGoldFields,3402(43.7%)casesof
silicosisweredetected.
•Mining,stonecutting,ceramic,pottery,agate,brickmaking,slatepencil,etc.
areafewofthemanyindustrieswhichareparticularlyatrisk

8. Silicosis in Indian Mines
*Chief Advisor of Factories# Directorate General of Mines Safety
@ National Institute of Occupational Health

9. Silicosis in Industry
Prevalence varies widely among various industries; lowest in Iron & Steel,
ordnance factories (2-3.5%) and highest in Agate, slate Pencil, Lead,
Zinc & Mica mining and Stone cutting/Quartz Grinding (>30%)

10. Silicosis In Indian Factories
Industry Prevalence (%)
Emery polishers
1
0.7
Iron and Steel
2
2.5
Ordnance factory
3
3.5
Micaprocessing
4
5.2
Glass bangle workers
5
7.3
Quartz crushing
6
12.0
Quartz mill-stone grinding
7
14.0
Ceramics and pottery
8
15.1
Brickmakers
9
16.7
Stone cutters
10-11
19.1 –35.2
Stone grinding
12
27.8
Agate workers
13-14
29.1 -38.0
Slate pencil workers
15
54.6

11. Silicosis In Indian Factories
1.MalikSK,BeheraDetal.IndianJChestDisAlliedSci.1985
2.BanerjeeDetal.IndJIndustrMed.1969
3.ViswanathanPetal.ArchEnvironHealth.1972
4.GangopadhyayBKetal.IndianJIndustrMed.1994
5.SrivastavaAKetal.IndianJIndustrMed.1988
6.NIOHAnnualreport1985-86
7.TiwariRRetal.IntJOccupEnvironHealth.2008
8.SaiyedbHNetal.IndianJMedRes.1995
9.RaoMNetal.AreviewofoccupationalhealthinIndia,ICMR.1955
10.SainiRKetal.JIndMedAssoc.1984
11.Gangopadhyayetal.IndianJIndustrMed1994
12.NIOHAnnualreport1988-89
13.RastogiSKetal.IntArchOccupEnvironHealth.1991
14.SadhuSGetal.IndianJIndustrMed.1995
15. SaiyedHN et al. Am J IndMed. 1985

12. Coal Workers Pneumoconiosis
•Coaldustconsistsofcarbon(60-
80%),apartfrom50different
elementsandoxides–including
Silica
•Higherthequalityofcoal–
higherthesilicacontentinthe
dust

13. CWP in India –Pariharet al 1997
•75351coalworkersin72collieries
•Overallprevalencefoundtobe3.03%,rangingfrom1.52%to4.76%
between10areas
•Mostcaseswerecategory-I(81.09%),followedbycategory-II(17.84%).
•Only3casesofPMFweredetected.
•Roundshapedopacitiesarepredominant(89.59%)inCoalWorker's
Pneumoconiosis.
•Amongtheopacities,'p'typewasmoreprevalent(48.29%)followedby
`q'type(40.62%).

14. CWP in India-Decreasing trend
Study No. of ParticipantsPrevalence (%)
Roy et al 1957 550 15
Ministry of Labourand
Employment. Govt. of
India. 1961(Pilot
study)
621 18.5
CMRS 1952 952 7
VishwanathanR.et al
1972
8822 10.8
VishwanathanR.et al
1977
455 3.5
ICMR study 1993 5777 2.84
Pariharet al 1997 75351 3.03

15. Non-occupational silicosis
Environmentalexposure
DuststormsinhillyregionintheHimalayas(Ladakh)
Saiyed,1991,Norboo,1991
Vicinityofindustry(Ambientairpollutionfromsilicadust)
Slatepencil(Mandsaur,MP)
Silicosis12.6% SilicoTB6.3%
Agateindustry(Khambhat,Gujarat)
ilicosis5.8% SilicoTB2.4%
BhagiaLJ,2012

16. Clinical Course
•Chronic/ClassicSilicosis:Developsfollowinglow-to-moderatelevel
exposuretosilicadustfor>20yrs
•AcuteSilicosis:Heavyexposurein<5-10yrs.Progressesfasterthan
chronicsilicosis;SometimesassociatedwithCTDs
•AcceleratedSilicosis:V.Highconcentrationofsilicaexposureoverweeks
tomonths–eg.Sandblasters,rockdrilling(ResemblesPAP)

17. Co-morbidities and complications
•Chronicairwayobstructionandrespiratoryfailure;Corpulmonale
•Silico-tuberculosis;Fungalinfections
•Pulmonaryfibrosis;Pneumothorax
•Broncholithiasis;Tracheobronobstruction
•Connectivetissuediseases
•Alveolarproteinosis
•Lungcancer

18. Silico-tuberculosis
•In autopsy material –over 25 %
(Gooding CG at al Lancet, 2:891,1946)
28.6% (SikandBK, PamraSP 1949)
•4.8% to up to 60% Quartz workers
•24.7% of former and 5.5% of current workers
•11.1% of female quartz mill workers,
•10.7% in stone cutters, 22.5 %in Slate Pencil Workers
(TiwariRR et al, NIOH 2007)
23%in stone quarries of Rajasthan
(P K Sishodiyaet al, NIMH 2012)
12%with silicosis had Sputum Positive PTB
(Keerthivasanet al, 2013)
Deshmukh, 1984
Tiwari2007, 2008

19. Risk factors
•Smoking
•Alcoholism
•HIVinfection
•Similarenvironmentalandworkingconditions
•Poverty
•Poornutrition

20. Special issues –Silico-tuberculosis
•Acceleratedseverityandincreasedoccurrenceofcomplications;NTM
infections
•TBmaycomplicatesimpleaswellasadvanceddisease
•SynergisticeffectofsilicosisandTB–proliferativefibrousreaction
Rapidfibrosisandrespiratoryfailure;maydevelopPMFwithcavitation

21. Silico-Tb -Diagnosis
•Symptomsofsilico-TBaremisleading
•RecoveryofAFBfromsputumisscarce
•InterpretationoftheCXRisdifficult
Opacitiesmaysurroundpre-existingnodules
Presenceofacavityinanodule;nocavitationinconglomerateshadows
Thenodulesinmiliarytuberculosisaresmallerthanthoseinsilicosis
Associatedpleural/pericardialeffusion
Rapidworseninginradiology

23. Treatment and Prophylaxis
•PoorresponsetoATTLongerdurationneeded.
•Prolongationofthecontinuationphasefrom4to6monthsdecreasedtherateof
relapsefrom22to7%
(Blumbergetal.2003)
TreatmentoflatentTB
•Chemoprophylaxis–HaloneorHR
CommunitywideapproachwithINHprophylaxis
(allemployeesofgoldmines–ThibelaTBinS.Africa)
(Fielding,2011)

24. Silico-mycosis
(Cryptococcus)
Adenocarcinomain silica nodule
Defining the Problem and Developing Solutions
PCCM,2011)
JindalSK (Text Book, PCCM,2011)

25. Developing solutions:
Treatment of Silicosis
•Nospecifictherapyforsilicosis
•Preventfurtherexposuretosilicadust
•Strongadvicetopatientstoquitsmoking
•Immunizationagainstinfluenza,pneumococci
•Experimentalapproachestriedwithoutsuccess:whole-lunglavage,
aluminuminhalation,andcorticosteroids
•ScreenforTBwithsputumAFBx2
•Complicationsshouldbetreatedappropriately

26. Issues to be addressed in India
•NationalPolicyonPreventionandEliminationofSilicosis
•Centralauthoritytocoordinateactivities
•Officialstatisticsonmorbidityandmortality
•Largescalecurrentepidemiologicalstudies
•Enforcementthroughlegislation
•Centralregistryforcasesofsilicosis
•Accountabilityofenforcementagenciesandindustry
•Awarenessamongworkers,employersanddoctors
•Adequateinfrastructurefordiagnosisandmanagement
•Legislationforsmallscaleandunorganizedsectorby
•Healthsurveillanceprograminindustry
•Diagnosisandtreatmentoftuberculosis

27. Preventive steps
•Dustsuppression,Process-isolation,ventilation
•Useofnon–silica–containingabrasives.
•Respiratorymasks
•Surveillanceofexposedworkerswithrespiratoryquestionnaires,
spirometry,andchestx-raysisrecommended

28. Engineering –control measures
•Cost-benefitanalysisdonefordust-controldevicesin500grinding
machinesinagateindustryinKhambat(Gujarat)
•Cost-effectiveanalysis
•Reductioninprevalenceofsilicosisandsilico-TB.
BhagiaandSadhu,2008

29. Silicosis –Passive surveillance
•OutpatientsettingofCoimbatoreMedicalCollege–tertiarycarecentre
betweenJanuary–December2012
•17cases(basedonH/oexposureandradiology)
ActiveTBin12%;OldTBin47%
Sivanmani,2013

30. NHRC Recommendations to Parliament of India
(2011)
(on Advice of Supreme Court of India, 2009)
Preventivemeasures:
•Occupationalhealth&dustsurveys
•Cost-effectiveengineeringcontrol
•Protectivegearsforworkers
•Dust-controldevices
•Education&awarenessactivities
•Occupationalhealth&safetycommittee
•Inter-sectoralcoordination
•Remedialmeasures
•RehabilitativemeasuresandCompensation

31. THANK YOU