ORIGINAl ARTICLE

Notification of Occupational and Work-Related Diseases and Poisonings inMalaysia, 1997- 1998

H Sirajuddin*, A Roslinah*, KG Rampal**, I Kuppusamy***, R Rohna****, M Aziz*, T C Aw*****,J R Beach*****, * Department of Public Health, Ministry of Health, **National University ofMalaysia, ***National Institute of Respiratory Medicine, ****Selayang Hospital, KualaLumpur, *****University of Birmingham, U.K.

IntroductionThroughout the world thete is an increasing interest inoccupational and work-related diseases. There isincreasing evidence that they contribute substantially tothe morbidity and mortality of working populations.Epidemiological notification schemes for occupationaland work-related diseases are now seen in manycountries including Finland, Canada, USA, and the UK,although many of these have concentrated initially atleast on lung diseases rather than the complete spectrumof disease l -4 In addition, in many countries someepidemiological information may be gained from othersources such as statutory notification schemes requiredfor investigation of work-related accidents and diseases,and the number of individuals applying for andreceiving workmen's compensation.

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In Malaysia, notification of occupational and work-related diseases has been required since the 1967Factories and Machinery Act6, mainly to allowinvestigation of such cases by the Department ofOccupational Safety and Health (DOSH). Subsequentlythe Occupational Safety and Health Act of 1994'reinforced this responsibility for both factory managersand doctors to report all cases of occupational and work-related diseases and poisoning to DOSH. However, thissystem has not worked well with few cases beingreported. Some of the probable factors contributing tounderreporting include reluctance of employers toreport problems arising within their own factories,doctors reluctance to break confidentiality (as requiredwith any reporting scheme) and poor recognition ofoccupational and work-related diseases by clinicians.

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ORIGINAL ARTICLE

This has been illustrated by the apparent disparitybetween the number of cases reported to DOSH and thenumber of cases awarded compensation by the SocialSecurity Organisation (SOCSO) in Malaysia. In 1996,SOCSO compensated 113 cases of occupationalpoisoning, 13 cases of occupational lung disease, and328 cases of occupational skin disease. An additionalfour cases of unspecified cancer due to asbestos exposureand 28 due to wood dust exposure were also compensated.Few of these cases were reported to DOSH.

Thus, it seems likely that there remains considerableunder-reporting of occupational and work-relateddiseases within Malaysia. Epidemiological data onoccupational and work related diseases nonetheless isimportant as only with good information can problemsbe identified and prioritised, and resources allocatedappropriately. During 1997, a number of initiatives wereundertaken to try to improve reporting and makedoctors more aware of their responsibilities in thisregard, particularly those in government service. Newsimplified reporting forms and procedures were introduced,and a number of workshops were held to introduce thesenew processes for reporting, as well as to emphasise theimportance of work as a cause of diseas~. This paperpresents a summary of information of all cases reportedduring approximately the first year following theintroduction of these modified reporting schemes.

Materials and MethodsNotification of cases of occupational lung diseases andpoisonings commenced in June 1997, and occupationaldermatoses in September 1997. Notifications to the endof November 1998 were included in this reported. Allpatients reported by any doctor who believed that on thebalance ofprobabilities a case of disease was caused by orrelated to work were included. Guidance documents forlung and skin diseases including instructions oncompleting the forms and diagnostic criteria were madeavailable to all government hospitals and governmentclinics through the Occupational and EnvironmentalHealth Unit of each state. These were distributedwidely to relevant clinicians, medical officers, medicalassistants and health inspectors.

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All cases reported to the occupational health unit of theMinistry of Health following the introduction of thenew reporting procedure were included in the analyses.On arrival within the unit reporting forms were checkedfor completeness, and then entered onto computer by. asingle operator (HS). Incomplete information wassought from the original doctor completing the formwhere possible. Data were entered onto an IBMcompatible personal computer and analyses undertakenusing SPSS Version 7.5.

Results

Lung diseases

Between June 1997 and November 1998, a total of 36cases of occupational and work related lung disease werereported (Table I). Of the cases reported, 22 were malesand 14 females; all the patients with pneumoconiosiswere males. There was no apparent relationship betweenoccupational lung diseases and smoking or atopy. Themean age of the reported cases was 31 years. The meanage of the individuals with pneumoconiosis wassomewhat greater at 54 years. The industrial sector andcause of the disease (when specified) are shown in Table I.

Occupational dermatosesOne hundred and eight cases of occupational dermatoseswere reported between September 1997 and November1998 (Table 11). Eighty seven percent had contactdermatitis. For the majority of notifications it was notpossible to reliably differentiate irritant from allergicdermatitis. Fifty six percent (n=61) of cases were male,44% female (n=47). In only four reports was thenotified case reported to be atopic. The mean age ofreported cases was 30 years. Seventy percent of all caseswere reported by dermatology clinics.

Poisoning by chemicals and pesticides.A total of 49 cases of occupational work-relatedpoisonings by chemicals and 46 cases of poisoning bypesticides were reported between June 1997 andNovember 1998 (Table III). Agro-cherriicals (n=14)and gases (n=9) were the commonest causes of chemicalpoisonings, while paraquat (n= 18) and organo-phosphates (n=15) the commonest causes of pesticidespoisonings. Pahang state recorded the greatest number

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NOTIFICATiON OF OCCUPATIONAL AND WORK-RELATED DISEASES AND POISONINGS

Table IOccupational Lung Diseases Notified to Ministry of Health, Malaysia

June 97 November 98

Health Care WorkersServices

DiseaseAsthma

Industrial Sector JobManufacturing labourer in sawmill

Store man in sawmilllabourer in palm oil millTextile manufactureEngineerMetal manufacturingElectrical appliancemanufacturingDispenserTeacher

CauseWood dustWood dustUnknownTextile treatmentsUnknownMetal working fluid

Solder fluxUnknownChalk dust

Inhalation accidents

Bronchitis/emphysemaInfections

Pneumoconiosis

Agriculture forestryand fishing

Palm oil estate workerManufacturingAgriculture forestryand fishingAgriculture forestryand fishing

Manufacturing

Services

Health Care Workers

Mining and quarrying

Manufacturing

Palm oil estate workerSettlerPalm oil estate workerPalm oil estate workerPesticideRubber manufactureTobacco grower

SettlerPalm oil estate workerPalm oil estate workerPalm oil estate workerPalm oil estate workerElectrician in saw millMetal manufacturingPublic relations workerGeneral administrationEducation servicesTaxi DriverStaff NurseAssistant NurseAttendantRock blastingRock blastingRock blastingQuarry workerMetal manufacturingProduction operator

PesticidesPesticidesPesticidePesticide

ChlorinePesticides/organic dustMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisMy TuberculosisSilicaSilicaSilicaSilicaunknown metalUnknown

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ORIGINAL ARTICLE

Table IIOccupational Skin Diseases Notified to Ministry of Health

September 1997 . November 1998Disease Industrial Sector Cause No. of CasesContact dermatitis Agriculture forestry and fishing Horse hair 1

Paraquat 2Unspecified 2

Manufacturing Glue and resins 10Coolants/oils/greases 7Metals 5Wood 4Solvents 4Other 1Unspecified 14

Construction Cement 3Other 1Unknown 1

Services Food and food products 4Gloves/latex 6Unknown 8

Health Care Woders Gloves 2Unspecified 19

Urticaria Services Unknown 3Occupational skin cancer Construction Tar 1

- Squamous cell (Rt. ear pinna)Manufacturing ? Paint- Basal cell (Lt. cheek)

Burns Construction Petrol 2Occupational Manufacturing Metal 2acne Mechanic ? Oil 1Nonspecified 4TOTAL 108

of poisoning cases

NOTIFICATION OF OCCUPATIONAL AND WORK-RELATED DISEASES AND POISONINGS

Table IIICases of Poisoning by Chemicals and Pesticides

Notified to Ministry of Health, MalaysiaJune 1997 . November 1998

Chemical Poisonings Number

The pattern of lung diseases within Malaysia issomewhat different to that reported elsewhere. There isa greater proportion of cases of pneumoconiosis, nearlyall of which are due to silica. In contrast there arerelatively fewer cases of lung diseases due to asbestosexposure. This may be because the use of asbestos inMalaysia has been less than in some other countries, andthe control of the fibres greater. It could also be due tothe long latency period .of asbestos related diseases.There were also relatively few cases of occupationalasthma notified.

A wide variety of causes have been implicated in the. aetiology of the cases of occupational lung diseasesnotified through the scheme. However, few cases werenotified as being due to agents commonly identified inother countries. For example, in the United Kingdomthe causative agents identified by the SWORD schemeand compensated by the Department of Social Security(DSS) most frequently were: isocyanates (SWORD15%, DSS 22%), flour and grain (SWORD 9%, DSS13%), colophony (SWORD 4%, DSS 7%) and wooddusts (SWORD 4%, DSS 8%)8. This may reflectdifferences in industrial processes between Malaysia andother countries, but could also suggest that a significantnumber of cases were not identified or notified.

%1.19.514.75.38.41.18.43.2

100

18.91.1

15.83.21.18.4

181

15318

95

Therapeutic drugs 1Gases 9Agro-chemicals 14Organic solvents 5Other Industrial Chemicals 8Mixed 1Other 8Unknown 3Pesticide Poisonings

ParaquatGlyphosphateOrganophospateCarbamateOrganochlorineOthersTOTAL

Discussion

Lung diseases

The total number of cases of occupational and work-related respiratory diseases reported does appear lowgiven that the scheme had been operating for 17 monthsby the time of these analyses. This probably reflectsconsiderable underreporting. In comparison, during1996 an estimated 3,322 new cases of occupational andwork-related lung diseases were notified to the SWORD(Surveillance of Work-related and OccupationalRespiratory Diseases) scheme in the UK, although thistoo may be an underestimate8 The SWORD schemeinvolves notification of cases by interested occupationaland chest physicians who volunteer to participate, and it

. is likely that some cases of occupational and work-related lung disease were never referred to participatingdoctors.

Another finding from these data was that some of thesources described for cases of tuberculosis appear to bepara-occupational rather that truly occupational or workrelated. This included hostel accommodation providedfor the palm-oil plantation workers. Nonetheless, therewere a number of truly occupational acquired infections,including three health care workers infected bytuberculosis while working in hospitals.

Occupational Dermatoses

Considerably more cases of occupational skin diseaseswere reported than lung disease, but it is likely thatthere is still considerable under-reporting of thesediseases. A survey of self-reported work-related ill-health in the UK in 1995, estimated a prevalence of66,000 cases of skin diseases9. Malaysia, with apopulation of approximately one third~f the UK mighttherefore expect a higher incidence than that reportedhere. However, the pattern of reported occupationalskin diseases in Malaysia, predominantly contact

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ORIGINAL ARTICLE

dermatitis, is similar to that reported by other schemes.The most commonly notified causative agent was epoxyresins used in electronics and other manufacturingindustries, with a smaller but still substantial number ofcases reported as due to exposure to oils or greases.

PoisoningsThere were more notifications of poisonings by bothchemicals and pesticides reported. through this schemethan cases of occupational lung and skin diseases. Allthe cases of poisoning that were notified presented withacute symptoms, and one died on arrival at the hospital.Disease episodes presenting in this way, with an acuteonset of symptoms, are easier to recognize and diagnoseand this probably contributed to the better reporting ofsuch cases. The more obvious rela.tionship to ahazardous exposure would also help recognition.Despite the fact that a relatively large number of caseswere reported, it is possible that some cases may not becaptured, especially those that did not seek treatmentand those who sought treatment at private clinics andhospitals. Eighty cases (84.2%) required admission andappear to have been managed appropriately.

Estimates from hospital surveys in the United States(1949-1988) indicate that approximately 20,000 peopleper year receive emergency care for actual or suspectedpesticide poisoning, and of these approximately 10%were hospitalized lO During the same period between 20and 40 people died each year of acute poisoning. If theratio of total poisonings to hospitalized poisonings werecloser to that in the United States (that is approximately10:1) this might again suggest under-reporting,particularly of less severe cases.

More males were reported to be affected than women,perhaps because more men were engaged in agriculturalemployment than women. Inhalation was the mainroute of entry reported, followed by dermal and oralroutes. The major causes of poisoning incidents were

paraquat, organo-phosphates and agro-chemicals. Agro-chemicals in this context exclude pesticides. Paraquat iswidely used throughout Malaysia in many agriculturalsituations and is highly toxic to human both by directcontact and when ingested in adequate doses. Organo-phosphates are widely used pesticides that may causeacure or chronic poisoning after exposure and untreatedpatients usually die within 24 hours of exposure whiletreated patients who die usually do so within 10 days".Organo-phosphates may be rapidly absorbed byinhalation, ingestion and through intact skin. The bestdescribed toxic effects on human are due to theinactivation of acetyl-cholinesterase enzymes within thenervous system, and the usual cause of death isrespiratory depression12.

Prevention of poisoning episodes depends very much onthe safe usage and storage of these chemicals. Simplemeasures to ensure safe systems of work, secure storage,good personal hygiene, and intelligent use of personalprotective equipment could prevent many cases ofaccidental poisoning each year. Adequate supervisionand training of agricultural workers could also help toreduce cases of poisoning. An understandable chemicalSafety Data Sheet should always be made available toworkers handling pesticides or chemicals.

ConclusionThe overall number of cases reported through thisnotification scheme is still low and probably there is agreat deal of under-reporting. Nonetheless theinformation obtained is very useful. Efforts are beingmade to improve this notification scheme, includingfurther training courses at both state and district levels.The Ministry of Health of Malaysia remains committedto reducing the incidence of these wholly preventablediseases, and this notification scheme comprises animportant tool to raise awareness and ensure appropriateallocation of resources in fulfilling this commitment.

u_ "!!Ill

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NOTIFICATION OF OCCUPATIONAL AND WORK-RELATED DISEASES AND POISONINGS

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