Food Safety Evaluation ­National and International Perspectives

Ramesh V. Bhatt and Pulkit Mathur

The maintenance of good healthdemands that food should not onlybe nutritious but also safe and ofgood quality. There has been grow­ing concern regarding environmen­tal contamination of food and exces­sive use of chemicals in food produc­tion and processing in the country inrecent times. The growth of the foodprocessing industry in India has con­sequently been very rapid, about 24per cent in 19951. The use of variousfood additives has also grown withthe industry.

Furthermore, as a part of mod­ern advances in agricultural technol­ogy and the application of pesticidesand fertilisers to crops, the use ofvarious compounds in animal hus­bandry and veterinary practice hasincreased, often resulting in residuesof these unintended contaminants per­sisting in the final food producF.

Apart from these relatively 'new'food contaminants, others such asaflatoxin which have been prevalentin different parts of the country, con­tinue to exert their deleterious effectsoccasionally3.

Though food habits are gener­ally governed by traditions and fam­ily backgrounds, they are subjectedto changes in lifestyles. With thebreakup of joint families, increasingnumbers of women are now joiningthe work force. This, together withthe increase in exposure of the popu­lation to mass media and advertise­ments, has caused processed foodsto increasingly find their way in theday-to-day menu of families4. A studyof the consumer's attitude towardsprocessed foods has revealed easyavailability to be the most importantreason for increased consumption fol­lowed by the view that these foodsare "more nutritious, tasty and easyto store"s.

This paper examines the chal­lenges faced by the scientific com­munity in evaluating the safety of thefood available to the population inthe context of a rapidly changing so­ciocultural and technological scenario.

Food processing in India: Thefood processing industry in India com­prises the organised and unorganisedsectors, the latter being much larger,consisting of small cottage or house­hold type manufacturing units. Moni­toring the quality of the processedfood prepared in this sector is espe­cially difficult.

It is the poor community whichis more exposed to food produced inthe unorganised sector, the quality ofwhich is suspect, as borne out byseveral independent surveys. Stud­ies conducted by the Industrial Toxi­cology Research Centre (ITRC) in thestate of Uttar Pradesh have revealedthat nearly 62 per cent of the artifi­cially coloured eatables in the ruralmarkets have non-permitted colourswhich are hazardous to health6.

Another study in the central andsub-urban areas of Calcutta also re­vealed the use of non-permitted coloursincluding some textile dyes by itiner­ant vendors, the unorganised sec­tors as well as small and cottagescale industries. In 6.6 per cent of thecases where permitted colours wereused, the statutory limit of 200 ppmwas exceeded with some eatablescontaining as much as 730 ppm ofcolour? Studies conducted by theNational Institute of Nutrition (NIN),Hyderabad, have shown the use ofadulterants like Lathyrus sativus andnon-permitted colours in urban streetfoods8.

Thus, in the Indian diet, non­permitted colours, permitted coloursadded in excess and a large numberof other adulterants are likely to bepresent. These have been shown toinduce a wide range of adverse reac­tions in humans. Metanil yellow, thefrequently used non-permitted colourin foods was found to cause toxicmethaemoglobinaemia9 and cyanosis11in two incidences of human food poi­soning. Among the permitted foodcolours, tartrazine has been most fre­quently reported to be associated withhypersensitivity responses11.

Technological advancements:The last two decades have seen a

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phenomenal increase in the qualityand quantity of processed foods avail­able. New technologies have led tothe development of new, modifiedforms of products and novel foods ornovel food ingredients (ie, those whichhave hitherto not been used for hu­man consumption to a significant extentand/or which have been produced byextensively modified or entirely newfood production processes). Biotech­nology has made it possible to pre­pare recombinant food proteins withmutation breeding and geneticengineering to develop high-yieldingseed varieties with the desired char­acteristics.

This increasing use of newermethods of food processing couldlead to the formation of new, toxiccompounds or enhance the allergenicityof the given food12.13.As the preva­lence of food allergy is also influ­enced by genetic and geographicalfactors as well as regional diets, it isof utmost importance that these foodsbe indigenously evaluated for safetyrather than relying on data generatedin some other country under differentenvironmental conditions.

REGIONAL PROBLEMS

Health problems arising due tothe consumption of special foods areregion specific as they largely de­pend on the cultural and dietary hab·its of the people. Data for the safetyevaluation of such foods has to begenerated indigenously. For example,the habit of chewing tobacco in theform of pan masala/gutka (perfumed,sweetened mixtures of tobacco andnut powder), is an emerging threat tohealth, especially among people inthe Indian subcontinent. A recent studyby NIN in collaboration with Govern­ment Dental College and Hospital,Hyderabad14, has found habitual chew­ing of pan masala/gutka to be associ­ated with the presentation of oralsubmucous fibrosis (OSF). Tradition­ally in India, only married adults havebeen consumers of betel quid. How­ever, during recent years with theadvent of attractive, convenientlypacked sachets and mass mediaadvertisements, the consumption ofpan masala by young people has in­creased. In fact, a prospective studyamong 1,790 patients attending adentalhospital in Hyderabad has found 23per cent of the diagnosed cases ofOSF to be aged between 14 and 19

years15. The habit of chewing tobaccoin the form of pan masa/a/gutka isthus emerging as a threat to healthnot only in India but also in otherparts of the world, notably amongpeople with origins in the Indian sub­continent.

Unlike in the developed coun­tries where people purchase pack­aged milk from bulk suppliers, in In­dia, the unorganised sector is still thedominant supplier. People get theirmilk directly from individual animalsor farmers with very small herds. Therisk of being exposed to veterinarydrug residues thus is greater in sucha situation. This fact was borne out ina study by NIN in Hyderabad2• Nearly87 per cent of the farmers interviewedwere found to be treating animalswithout consulting a veterinarian andalmost 73 per cent of the milk samplesfrom individual animals was found tocontain antibiotic residues. In con­trast, most of the pooled milk samplestested negative for these residues.

CHAllENGE3 AHEAD

With the liberalisation of tradein India, there is a growing list of foodadditives and processing aids whichrequire to be approved by the regula­tory authorities for their use in differ­ent foodstuffs. There is an urgentneed for the scientific community inIndia to evaluate whether these addi­tives are indeed technological ne­cessities and whether they pose ahazard to the Indian consumer.

The rationale of fixing a uniformpermissible limit for different foodsmay not be justified. There is a needto fix the levels based on the overallintake of the specific food which willvary from country to country depend­ing on the dietary habits of people.Hence, India needs to generate itsown exposure data notjustfor coloursbut for all other food additives.

CASE STUDIES OF SELECTEDFOOD ADDITIVES

A few examples of specific prob­lems may be mentioned.

Silicon: Recently some compa­nies have sought permission to useamorphous silicon dioxide as ananticaking agent in various food prod­ucts including baby food, while someothers have requested butylated hy­droxy anisole (BHA) and talc be al­lowed in chewing gum.

Although the use of these foodadditives is permitted in a number ofcountries, the potential health effectestimated for the population in othercountries may not be applicable inthe Indian context because of thedifferent dietary habits. For example,the average intake of silicon in the USdiet is about 20-50 mg/day17 whereasthe Indian diet may have much higherlevels of silicon, that is, 111-424 mg/day, mostly due to a higher intake ofcereals and plant foods18.

Studies have shown that rumi­

nants consuming plants with highsilicon content develop renal calculi19•Anasuya and Rao 20 observed that theurine of the majority of stone-formersstudied contained higher content andconcentration of silicon compared tonon-stone-formers. Recent studies atNIN have also shown silicon to be animportant risk factor for aggravatingfluorosis, the prevalence of which ishigh in certain parts of India21. Thisexample illustrates that safety evalu­ation is very much dependent on theenvironment.

Talc: Use of talc as a filler in­stead of calcium carbonate in chew­ing gum flavour also needs criticalevaluation in the Indian context. Talcis nothing but a hydrous silicate ofmagnesium. Commercial talc is notpure mineral talc alone but also fib­rous silicates which in part are classi­fiable as asbestos. Besides the riskposed by silicates, asbestos expo­sure has been shown to increase theincidence of gastrointestinal cancer.In fact, asbestos-contaminated talcmay playa causative role in cancersof the stomach among the Japanesewho have a preference for talc­coated rice22.

BHA: BHA is an extensively usedantioxidant in various foods such asedible oils and fats, cereal products,biscuits, breakfast foods, dry fruits,potato chips, flavour concentrates,etc. BHA has been shown to producehyperplasia and/or tumours specifi­cally in the forestomach of rats23. It isalso weakly oestrogenic having stimu­lator effects on both the transcrip­tional activity of the human oestrogenreceptor and the growth of breastcancer cellsin ViV024• BHA is a permit­ted food antioxidant in India but onlyin a specific number of foods. Beforeit is allowed to be added to otherfoods, there is a need to evaluatewhether the total intake of BHA throughthe Indian diet exceeds the ADllevels

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(0.5 mg/kg body weight).

Hence great caution needs tobe exercised in permitting the addi­tion of an increasing number of foodadditives in diets without first evalu­ating the total intake of that additivefrom all sources in the Indian diet.This is especially true for infant foodssuch as milk powder and foods con­sumed more frequently by childrensuch as chewing gum, confection­ery, etc.

SELECTIVE APPLICATION OFTOXICOLOGICAL DATA

An example of this is the recentproposal by the Codex AlimentariusCommission (CAC) to reduce thepermitted level of sulphur dioxide insugar from 40 to 15 mg/kg. The os­tensible objective of the CAC is toreduce the overall consumption ofsulphur dioxide by population groups.According to the revised limits of theCAC, the maximum level for sulphurdioxide allowed in sugar is 15 mg/kg(lowest) and in wine (grape) 2,000mg/kg (highest). For the rest of thefoods the levels are in between. Thereappears to be no justification for re­ducing the level only in one product,ie, sugar.

Surveys on the intake of sulphite/sulphur dioxide from various foodscarried out in developed countrieshave shown that the ADI for this addi­tive (ie, 0.7 mg/kg body weight or 42mg/day in a 60 kg adult) is likely to beexceeded if proper regulatory mea­sures are not taken. The average con­sumption of sulphur dioxide/sulphitein France is 20 mg/day/person. Thedaily intake is about 29-40 mg in av­erage consumers of wine, cider andbeer and it is 10 mg in occasionalconsumers. On the other hand, inteetotallers, the average intake of sul­phur dioxide is only 1.96 mg/day25,

Thus, it is obvious that morethan 90 per cent of the intake is throughalcoholic beverages such as wine. Ifat all there is a need to regulate theintake of sulphur dioxide, it is essen­tial to minimise the consumption ofsulphur dioxide through alcohol. De­creasing the permitted limit in sugarwill only create technological prob­lems for sugar manufacturers in de­veloping nations where sulphur diox­ide is used as a bleaching agent.This also raises doubts about themotivation behind reducing the addi­tion of sulphur dioxide in sugar. Is it

dictated by certain groups that aremarketing their good products in cans?High levels of sulphur dioxide in cannedfoods are likely to corrode the tins ifstored for a long period of time.

Need to resist pressure: Todate, there has been only a limitedeffort to generate both toxicity anddietary exposure data in India. In theabsence of valid data, pressures arelikely to be exerted by vested inter­ests to accept the recommendationsof the international expert commit­tees in toto in the name of 'interna­tional harmonisation'. Such pressuresneed to be resisted where the majorgoal is providing safe food to thenation. Objective, scientific, fair andbalanced decisions need to be takenby the appropriate food control agencyin the country, taking into accountthe data generated within the coun­try, after giving due consideration tothe toxicological data available fromabroad.

CONCLUSION

It is imperative to constantly re­evaluate the safety information avail­able. There is need for greater inter­action between industry, government,research institutions and voluntaryconsumer associations for assess­ing the safety of the ever increasingnumber of technological innovationsand modifications of familiar food­stuffs.

Although it is not unwise to ac­cept valuable information generatedworldwide, it is essential to generateunbiased data in one's own countrygiving due consideration to the envi­ronment, dietary habits and ethnicfactors which have a bearing on theevaluation of the safety of the foodsupply in a country.

References

1. Anon: Indian Food Industry, 15:5, 1996.

2. Sudershan, R.V. and Bhat, R.V.: A survey onveterinary drug use and residues in milk in Hyderabad.Food Additives and Contaminants, 12:645-650,1995.

3. Bhat, R.V., Vasanthi, S., et a/,: Aflatoxin B, con­tamination in groundnut samples collected fromdifferent geographical regions of India: A multicentricstudy. Food Additives and Contaminants, 13:325­331,1996.

4. Potty, V.H.: Trends in food consumption andfood industry developments - A global perspec­tive. Indian Food Industry, 14:36-48, 1995.

5. Shaw, A., Mathur, P. and Mehrotra, N.N.: Astudy of consumers' attitude towards processedfood. Indian Food Packer, 47:29-41, 1993.

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7. Biswas, G., Sarkar, S. and Chatterjee, T.K.:Surveillance on artificial colours in food productsmarketed in Calcutta and adjoining areas. J FoodSci Technol, 31:66-67, 1994.

8. Bhat, R.V., Waghray, K. and Rambabu, J.P.: Areport on urban street foods in Hyderabad andSecunderabad. National Institute of Nutrition,Hyderabad, 1994.

9. Sachdeva, S.M., Mani, K.V.S., Adaval, S.K.,Jalpota, Y.P., Rasela, K.C. and Chadha, D.S.: Ac­quired toxic haemoglobinaemia. Journal of the As­sociation of Physicians of India, 40:239-240, 1992.

10. Chandra, S.S. and Nagaraja, T.: A food poison­ing outbreak with chemical dye - an investigationreport. Medical Journal of the Armed Forces ofIndia, 43:291-293, 1987.

11. Miller, K.: Sensitivity to tartrazine. Br Med J,285:1597-1598,1982.

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13. Nordlee, J.A., Taylor, S.L., Townsend, J.A., Tho­mas, L.A. and Bush, R.K.: Identification of a brazilnut allergen in transgenic soybeans. N Engl J Med,334:688-692, 1996.

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pan masala and betel quid. Clinical Toxicology,34:317-322,1996.

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18. Anasuya, A., Bapu Rao, S. and Paranjape, P.K.:Fluoride and silicon intake in normal and endemic

fluorotic areas.J Trace Elements Med Bioi, 1996 (inpress).

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20. Anasuya, A. and Rao, B.N.S.: Effect of fluoride,silicon and magnesium on the mineralising capac­ity of an inorganic medium and stone-formers urinetested by a modified in vitro method. Biochemical

. Medicine, 30:146-156,1983.

21. NIN: Reiationship between dietary silicate andfluoride toxicity in endemic fluorosis. Annual Re­port. National Institute of Nutrition, (Hyderabad)44-45, 1993-94.

22. Meriiss, R.R.: Talc and asbestos contaminationof rice (letter). JAMA, 216:2144, 1971.

23. Poulsen, E.: Safety evaluation of substancesconsumed as technical ingredients (food additives).Food Additives and Contaminants, 8: 125-134, 1991 .

24. Jobling, S., Reynolds, T., White, R., Parker, M.,Sumpter, J.P.: A variety of environmentally persis­tent chemicals, including some phthalate plasticisers,are weakly oestrogenic. Environmental Health Per­

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France. Food Additives and Contaminants, 9:541­549,1992.

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28. Michils, A., Vandermoten, G., Duchateau, J.and Vernault, J.C.: Anaphylaxis with sodium ben­zoate. Lancet, 337:1424-1425,1991.

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FOUNDATIONNEWS

• Scientific Report 12: 'Use of Caro­tene-rich Foods to Combat Vitamin ADeficiency in India - A MulticentricStudy' edited by Dr Subadra Seshadri,has been released.

Meetings• The Third Foundation Day Lec­ture was delivered by Dr M.S.Swaminathan on: 'A Food and Nutri­tion Secure India - The Final Mile­stone' on November 29, 1996.

• Study Circle Lectures

October 30: Dr Caroline Fall (MRCEnvironmental Epidemiology Unit, Uni­versity of Southampton, UK) on: 'TheFoetal Origins of Adult Chronic Dis­ease'.

December 16: Dr A.K. Susheela (Pro­fessor, Department of Anatomy, All MS,New Delhi) on: Fluoride 'Nutrient' or'Contaminant'?

• President's Engagements

Lecture: 'Nutritional Considerationsin Agriculture and Food Policies' atthe Plenary Session of the Third Ag­ricultural Congress on March 12, 1997,in Ludhiana.

• Fund Raising

The Foundation is grateful toDr R. Thiagarajan for her generousdonation.

The Foundation is gratefulto FAG for a matching grant

towards the cost ofthis publication

Edited by Manisha Pant for the Nutrition Foundation of India, C-13 Qutab Institutional Area, New Delhi 110 016.Printed by Vashima Printers. Designed and produced by Media Workshop.