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    INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY

    WORLD HEALTH ORGANIZATION





    SAFETY EVALUATION OF CERTAIN 
    FOOD ADDITIVES



    WHO FOOD ADDITIVES SERIES: 42





    Prepared by the Fifty-first meeting of the Joint FAO/WHO
    Expert Committee on Food Additives (JECFA)





    World Health Organization, Geneva, 1999
    IPCS - International Programme on Chemical Safety

    EVALUATION OF NATIONAL INTAKE ASSESSMENTS OF BUTYLATED HYDROXYTOLUENE 
    (BHT)

    First draft prepared by
    Dr Philippe Verger
    Observatory of Food Consumption, Paris


    1.  INTRODUCTION

         The Committee assessed the intake of butylated hydroxytoluene
    (BHT), for which maximum limits have been proposed in a wide range of
    solid foods in the draft General Standard for Food Additives (GSFA)
    being developed by the Codex Committee on Food Additives and
    Contaminants (CCFAC). An ADI of 0-0.3 mg/kg bw has been allocated to
    BHT (Annex 1, reference 116).

         BHT is generally used as an antioxidant in products containing
    fats or oils. It can be use in conjunction with butylated
    hydroxyanisole,  tert-butylated hydroquinone, and propyl gallate,
    providing a synergistic combination of antioxidants.

         Information was provided by 10 countries: Australia, Brazil,
    China, Finland, France, Japan, New Zealand, Spain, the United Kingdom,
    and the United States. A combined assessment was provided by Australia
    and New Zealand (Aus-NZ). The submitted intake assessments were based
    on 'poundage', household economic surveys, sales data, model diets, or
    individual dietary records. Table 1 summarizes the submissions.

        Table 1. Summary of submissions on butylated hydroxytoluene

                                                                                                 

    Country                   Budget     Poundage    FBS/HES/      Model     Individual dietary
                              method     data        sales data    diets     records
                                                                                                 

    Australia-New Zealand     x                                    x         x
    Brazil                    x                      x                       
    China                     x          x                         x         
    Finland                              x                                   
    France                                           x                       x
    Japan                                                          x         
    Spain                     x          x           x                       
    United Kingdom                       x                         x         x 
    United States                        x                         x
                                                                                                 

    FBS, food balance sheet; HES, household economic survey; sales, retail stores
    
    2.  SCREENING OF BUTYLATED HYDROXYTOLUENE BY THE BUDGET METHOD

         National submissions of intakes derived by the budget method
    indicate whether BHT is used in solid foods. The Codex GSFA proposes
    that BHT be permitted in a wide range of solid foods. Table 2
    summarizes data for each country on the permitted patterns of BHT use,
    the proportion of the solid food supply likely to contain BHT, the
    maximum levels of BHT permitted, and a comparison of the levels with
    the theoretical maximum level calculated by the budget method for that
    country.

         The theoretical maximum level of use for BHT in solid foods was
    less than the national maximum permitted level of use in the four
    countries that submitted data and was also less than the GSFA level of
    1000 mg/kg. Detailed assessments of the intake of BHT from its use in
    solid foods are therefore required.


    3.  ASSESSMENTS OF INTAKE OF BUTYLATED HYDROXYTOLUENE

    3.1  Assessments based on data on poundage (disappearance)

         Estimates of the amount of BHT available  per capita based on
    poundage data are given in Table 3 for five countries and compared
    with the JECFA ADI of 0-0.3 mg/kg bw for BHT. The estimated intakes
    are all lower than the ADI but vary from 0.003 to 0.11 mg/kg bw per
    day (1-40% of the ADI) in recent studies. Results obtained by the
    poundage method show a large decrease in use of this additive in the
    United States between 1987 and 1995.

    3.2  Assessments based on data from household economic surveys or 
         sales

         Four countries submitted data based on household surveys or
    sales, in which national maximum levels of use were assumed national
    in each country. The data are summarized in Table 4. The estimated
    intakes are all lower than the ADI, ranging from 0.052 mg/kg bw per
    day in Brazil to 0.1 mg/kg bw per day in Spain (17 and 33% of the ADI,
    respectively). Although high consumers generally cannot be identified
    from household economic surveys or sales data, the submission from
    France included estimates of high consumption derived by dividing
    household consumption by the number of members and then estimating
    high intake for individual consumers.

    3.3  Assessments based on data from model diets

         Five countries submitted data based on model diets, details of
    which are summarized in Table 5. The results cannot be compared
    directly because different assumptions were made. The model diets used
    in Aus-NZ and the United Kingdom were constructed to estimate the BHT
    intake of a high consumer, assuming a maximum permitted level of
    additive. The United States model diet was constructed to predict the
    BHT intake of a long-term consumer by using food consumption data
    derived from food frequency data for 1982-88 from the Market Research

    Corporation of America and average portion sizes from a three-day
    national food consumption survey conducted in 1987-88 by the US
    Department of Agriculture. Maximum additive levels were assumed. The
    Japanese model diet (based on a total diet survey) included analysed
    concentrations of food additives with national food consumption data
    to derive an estimate of the actual BHT intake of the average
    consumer.

         The estimates of BHT intake based on the models of Aus-NZ and the
    United Kingdom do not exceed the ADI when additive levels at the
    national standards are assumed (0.02 and 0.09 mg/kg bw per day and 10
    and 30% of the ADI, respectively), but largely exceed the ADI if GSFA
    levels of use are assumed (5.3 and 6.0 mg/kg bw per day, respectively,
    corresponding to 1800 and 2000% of the ADI). The last result is
    consistent with estimates of BHT intake based on the Chinese and
    United States models with the GSFA standard, which are 0.7 mg/kg bw
    per day (230% of the ADI) and 0.99 mg/kg bw per day (330% of the ADI)
    for average consumers and 4.4 mg/kg bw per day (1600% of the ADI) and
    2.0 mg/kg bw per day (660% of the ADI) for high consumers,
    respectively. When national standards for BHT are used in the United
    States model, the ADI is also exceeded. The Japanese estimate of BHT
    intake is much lower than those from other model diets because the
    actual concentrations of BHT detected are used, which are much lower
    than the maximum permitted levels.

    3.3  Assessments based on individual dietary records

         Estimates of the intake of BHT based on individual dietary
    records were submitted by three countries. In each case, means and
    percentiles were derived from individual intake estimates adjusted for
    individual body weight (except in the United Kingdom). The assumptions
    made in deriving these estimates and the estimates themselves are
    summarized in Table 6. The estimates show that the intakes are lower
    than the ADI for both mean and high consumers in all countries. The
    estimates based on GSFA levels in Aus-NZ are higher than those based
    on national levels of use and exceed the ADI for both mean (0.7 mg/kg
    bw per day and 240% of the ADI) and high consumers (1.8 mg/kg bw per
    day and 580% of the ADI).

         Table 7 summarizes the results of intake assessments based on the
    levels of use of the GSFA. The results for Aus-NZ, China, and the
    United Kingdom are consistent in showing a potential to exceed the
    ADI.

    3.5  Food groups that are major sources of butylated hydroxytoluene

         Assessment of intake based on GSFA levels of BHT, in conjunction
    with the data on food consumption supplied by countries, points to
    certain foods as major contributors to the overall intake of BHT. The
    ADI would be exceeded when 90 g/day of any food containing more than
    200 mg/kg BHT, 45 g/day of any food containing more than 400 mg/kg
    BHT, or 18 g/day of any food containing more than 1000 mg/kg BHT was
    ingested. Some of the GSFA levels are the result of a high permission

    for one type of food within a food grouping which drives the permitted
    use level for the whole group to an unlikely high level. This is the
    case for edible fats and oils (75-200 mg/kg), confectionery (200-750
    mg/kg), and frozen fish, fish fillets, and fish products (100-1000
    mg/kg).


    4.  EVALUATION OF ESTIMATES OF INTAKE OF BUTYLATED HYDROXYTOLUENE

         Screening of BHT by the budget method indicated that use of BHT
    as an additive requires further assessment. Inclusion of national
    proportions of the food supply that may contain BHT in the budget
    method of screening did not change this decision.

         Estimates of the intake of BHT were submitted by 10 countries.
    All of the estimates based on model diets or individual consumption
    data combined with GSFA levels of use show that the ADI is
    consistently exceeded. The mean intake is estimated to be between 0.70
    and 0.99 mg/kg bw (230 and 240% of the ADI for China and the United
    States), and the intake of high consumers is estimated to be 2.0-6.0
    mg/kg bw (690-2000% of the ADI).

         Intake estimates based on national levels of use are relatively
    consistent, ranging from 0 to 0.11 mg/kg bw per day (0-30% of the ADI)
    on the basis of poundage, 0.052-0.1 mg/kg bw per day (20-40% of the
    ADI) on the basis of household surveys or sales data, 0.02-0.09 mg/kg
    bw per day (10-30% of the ADI) on the basis of model diets and
    national levels of use (except for the United States), and 0.02-0.1
    mg/kg bw per day (0.1-30% of the ADI) on the basis of individual
    consumption data.

         Two exceptions must be noted. The first is estimates for mean and
    high consumption based on a model diet and authorized levels of use in
    the United States (0.39 and 0.78 mg/kg bw per day and 130 and 260% of
    the ADI, respectively). This result can be explained by the high
    levels of BHT authorized in that country. The second is the low
    estimate (0.00089 mg/kg bw per day or 0.003% of the ADI) in the study
    provided by Japan, which is based on the concentrations of BHT found
    in a total diet survey.


    5.  CONCLUSIONS AND RECOMMENDATIONS

         The Committee recognized that the ADI for BHT is unlikely to be
    exceeded on the basis of the estimated intakes in the 10 countries for
    which data were available but that it might be exceeded when the
    proposed maximum limits in the GSFA are assumed.

         The Committee recognized that BHT is likely to be used in
    conjunction with other antioxidants, such as  tert-butylated
    hydroquinone and butylated hydroxyanisole, which act synergistically
    with BHT. Consequently, the amount of BHT used in practice will be
    lower and it will be used in fewer foods than assumed in the

    estimates. All of the estimates except that from Japan are based on
    the assumption that BHT is the only antioxidant in foods where use is
    permitted and that all such foods contain it at maximum permitted
    levels. The actual intakes of BHT will depend on the relative
    proportions of antioxidants used in foods and on the proportion of
    foods in any one category that contains the additive.

     Recommendations to the Codex Committee on Food Additives and 
     Contaminants

         The Committee identified certain food groups that could
    potentially contribute to a high intake of BHT. The Codex Committee
    may wish to review the appropriate levels of BHT in the following food
    groups: category 2.1, 'edible oils and fats'; category 9.2, 'fish and
    fish products'; and category 5.3, 'chewing gum'.


    6.  BIBLIOGRAPHY

    Australia New Zealand Food Authority (1997)  Aus-NZ Food Standards 
     Code, Canberra.

    Baines, J. Data sheets for Australia for TBHQ, BHA, BHT, sulfites, and
    benzoates. Personal communication. Australia-New Zealand Food
    Authority, Canberra, to J. Paakkanen, FAO, 5 January 1998.

    Chen Junshi. Food additive intake from China. Personal communication.
    Chinese Academy of Preventive Medicine, Beijing, to J. Paakkanen, FAO,
    16 March 1998.

    Codex Committee on Food Additives and Contaminants (1997)  Report of 
     the Twenty-ninth Session of the Codex Committee on Food Additives 
     and Contaminants, Rome, Food and Agriculture Organization of the
    United Nations (document ALINORM 97/12A, Appendix V).

    Codex Committee on Food Additives and Contaminants (1998)
    Consideration of the Codex General Standard for Food Additives:
    Proposed draft revised annex A at step 3. Request for comments and
    information. Rome, Food and Agriculture Organization of the United
    Nations (document CX/FAC 98/9).

    European Commission (1995) European Union Directive 95/2/CE, Brussels.

    Fisher, C.E. Dietary exposure in the United Kingdom to the five
    additives referred to JECFA by CCFAC. Personal communication. Joint
    Food Safety and Standards Group, London, to J. Paakkanen, FAO, 29
    April 1998.

    Ishii, K. Use levels and intake estimates of certain food additives in
    Japan. Personal communication. Japan Food Additives Association,
    Tokyo, to J. Paakkanen, FAO, 10 May 1998.

        Table 2. Estimation of theoretical maximum level for butylated hydroxytiluene (BHT) by the budget method 

                                                                                                           

    Country                   % food supply     National maximum    GSFA maximum      Theoretical maximum
                              containing BHT    level (mg/kg)       levela (mg/kg)    level (mg/kg)
                                                                                                           

    Australia-New Zealand     50                70                  1000              24
    Brazil                    25                200                 1000              48
    China                     20                200                 1000              60
    Spain                     5                 400                 1000              240
                                                                                                           

    GSFA, General Standard for Food Additives
    a Maximum use level proposed is 1000 mg/kg for 9.2.1, 'frozen fish, fish fillet and fish products, 
      including molluscs, crustacea and echinoderms'.
    


        Table 3. Estimates of intake of butylated hydroxytoluene (BHT) based on 
    poundage data

                                                                                    

    Country           Date       Consumers    Estimated intake of          % ADIa
                                 (millions)   BHT (mg/kg bw per day)
                                                                                    

    China             1992       1200         0.016                        5
                                              70% of total population

    Finland           1980       4.9          0                            0
                      1994       5.1          0                            0

    Spain             ?          0.07         23
                                              85% of total population

    United Kingdom    1984-86    56           0.003                        1

    United Statesb    1987       240          0.056 (mean)                 19
                                              0.11 (90th percentile)       37
                      1995       260          0.023 (mean)                 7
                                              0.046 (90th percentile)      14
                                                                                    

    a JECFA ADI, 0-0.3 mg/kg bw
    b Assuming that 100% of consumers ingest BHT and that the intake for 90th 
      percentile consumers is twice the mean
    

        Table 4. Estimates of intake of butylated hydroxytoluene (BHT) based on household economic surveys and sales data

                                                                                                                         

    Country    Date       Survey               Assumptions                                  Estimated intake     % ADIa
                                                                                            of BHT (mg/kg bw 
                                                                                            per day)
                                                                                                                         

    Brazilb    1992-96    AC Nielsan Brazil;   Maximum national use levels for all foods    0.052                17
                          sales data

               1984-94    Datamark             Maximum national use levels for all foods    0.08                 26

    France                Sales data           Maximum European Union levels of use         0.089                30
                                               Adjustment for catering outside the home

    Spain      1993       Household survey     All foods in permitted groups contain BHT    0.1                  33
                                                                                                                         

    a JECFA ADI, 0-0.5 mg/kg bw
    b Assumed maximal level in final coconut and chewing gum products even though the use level in coconut is based on 60% fat 
      content and that in chewing gum is based on 20% gum content, resulting in overestimates of BHT intake

    Table 5. Model diets used to estimate intake of butylated hydroxytoluene (BHT) 
                                                                                                                                              

    Country  Date      Survey                        Assumptions                                 Model                    BHT intake  % ADIa
                                                                                                                          (mg/kg bw
                                                                                                                          per day)
                                                                                                                                              

    Aus-NZ   1983      National, 24-h recall;        Two models: Aus-NZ/GSFA                     High consumerb/          0.02        10
                       adults, 25-64 years;          -- maximum levels (Aus-NZ or GSFA)          Aus-NZ permissions
                       sample, 6254                  -- 95th percentile high consumption level   High consumerb/          5.3         1800
                                                     -- modified GSFA classification system      Aus-NZ permissions

    China    1992      National household survey,    One model                                   Average consumer/        0.7         230
                       24-h recall; 30 provinces;    -- maximum GSFA levels                      GSFA permissions
                       sample, 91 818                                                            High consumer/           4.9         1600
                                                                                                 GSFA permissions

    Japan    1994      National nutrition intake     One model: Japan                            Average consumer         0.00085     0.003
                       survey                        -- Analysed food additive concentrations    levels/measured BHT
                                                        (zero values when not detected)

    United   1986-87   National; 7-day weighed       Three models: UK adult/child, GSFA          High consumerb/          0.09        30
    Kingdom            record; adults, 16-64 years   -- maximum additive levels (EU)             UK permissions/adult
                                                     -- unit quantity diet (Codex model with     High consumerb/          0.17        60
                                                        GSFA levels)                             UK permissions/child
             1992      National; 7-day weighed       -- 97.5th percentile high consumption       High consumerb/          6.0         2000
                       record; children, 1.5-4.5        level (UK adult/child models)            GSFA permissions
                       years                         -- GSFA classification system

    United   1982-88   14-day menu obtained          Two models: US and GSFA                     Long-term consumer/USA   0.39        130
    States             from MRCA food                -- maximum additive levels (US or GSFA)     permissions/mean
                       frequency data (1982-87)      -- 90th percentile high consumption level   Long-term consumer/USA   0.78        260
                       combined with portion         twice mean consumption                      permissions/90th 
                       sizes from USDA/NFCS          -- all respondents are consumers            percentile                           0.99330
                       (1987-88); > 2 years          -- GSFA classification system               Long-term consumer/GSFA
                                                                                                 permissions/mean
                                                                                                 Long-term consumer/GSFA  2.0         660
                                                                                                 permissions/90th 
                                                                                                 percentile
                                                                                                                                              

    Table 5 (continued)

    Aus-NZ, Australia-New Zealand; GSFA, General Standard for Food Additives; EU, European Union; MRCA, Market Research Corporation of America;
    USDA/NFCS, US Department of Agriculture/National Food Consumption Survey

    a JECFA ADI, 0-0.3 mg/kg bw
    b Assumed to consume one food with potentially highest BHT intake from two major food groups at the 97.5th percentile (United Kingdom) or 
      95th percentile (Aus-NZ) and from one food with potentially highest BHT intake from each of the other major food groups at a mean level 
      for all respondents

    Table 6. Estimates of intake of butylated hydroxytoluene (BHT) based on individual records 

                                                                                                                        

    Country         Date      Survey                 Model                                          BHT intake    % ADIa
                                                                                                    (mg/kg bw 
                                                                                                    per day)
                                                                                                                        

    Aus-NZ          1983      National survey;       Mean intake (population = consumers) Aus-NZ    0.02          7
                              24-h recall;           Mean (population = consumers) GSFA             0.7           240
                              adults, 25-64 years;   95th percentile (consumers) Aus-NZ             0             0
                              sample, 6254           95th percentile (consumers)  GSFA              1.8           580

    France          1993-94   National survey;       Mean intake (population) EU                    0.033         11
                              7-day record;          90th percentile EU                             0.071         24
                              5-75 years;            95th percentile EU                             0.089         30
                              sample, 1116           Corrected mean intake (population) EU          0.001         00.3

    United Kingdom  1986-87   National survey;       Mean intake (population = consumers) EU        0.04          13
                              7-day weighed          97.5th percentile (consumers) EU               0.1           33
                              record; adults,
                              16-64 years;
                              sample, 3000
                                                                                                                        

    Aus-NZ, Australia-New Zealand; GSFA, General Standard for Food Additives; EU, European Union
    a JECFA ADI, 0-0.3 mg/kg bw

    Table 7. Summary of estimates of intake of butylated hydroxytoluene (BHT) based on additive levels permitted within 
    the General Standard for Food Additives

                                                                                                                              

    Country                  Model                                            Intake of BHT                          % ADIa
                                                                                                                   
                                                                              mg/person per day   mg/kg bw per day
                                                                                                                              

    Australia-New Zealand    Individual records, mean intake                  51                  0.85               240
                             Individual records, 95th percentile consumers    125                 2.1                690


    China                    Model diet, mean intake                          41                  0.7                230
                             Model diet, high consumers                       290                 4.9                1600

    United States            MRCA, mean intake                                59                  0.99               330
                             MRCA, pseudo-90th percentile consumers           120                 2.0                660
                                                                                                                              

    MRCA, Market Research Corporation of America
    a JECFA ADI, 0-0.3 mg/kg bw
    

    Ishiwata, H., Nishijima, M., Fukasawa, Y., Ito, Y. & Yamada, T. (1997)
    Evaluation of the contents of BHA, BHT, propylene glycol, and sodium
    saccharin in foods and estimation of daily intake based on the results
    of official inspection in Japan in fiscal year 1994.  J. Food Hyg. 
     Soc. Jpn, 39, 89-100.

    Ministry of Public Health (Spain) (1998) Calculation of certain food
    additives in Spain. Submitted to FAO.

    National Food Administration (Finland) (1998) Estimated intake of
    certain food additives in Finland. Submitted to FAO.

    Rulis, A.M. United States intake data on BHA, BHT, TBHQ, sulfites, and
    benzoates. Personal communication. Food and Drug Administration,
    Washington DC, to J. Paakkanen, FAO, 24 February 1998.

    Toledo, M.C.F. Brazilian intake estimates of BHA, BHT, and TBHQ.
    Personal communication. University of Campinas, to J. Paakkanen, FAO,
    26 February 1998.

    United States Department of Agriculture (1996) Nationwide food
    consumption survey: 1989-91. Technical Information Service,
    Springfield, VA, United States.

    Verger, P. Estimation of the theoretical maximum intake of certain
    food additives in France. CNERNA, Paris. Submitted to J. Paakkanen,
    FAO, 16 March 1998.
    


    See Also:
       Toxicological Abbreviations
       Butylated hydroxytoluene (BHT) (WHO Food Additives Series 15)
       Butylated hydroxytoluene (BHT) (WHO Food Additives Series 18)
       Butylated hydroxytoluene (BHT) (WHO Food Additives Series 28)
       Butylated Hydroxytoluene (BHT) (IARC Summary & Evaluation, Volume 40, 1986)