Content uploaded by J.C. Hanekamp
Author content
All content in this area was uploaded by J.C. Hanekamp on Mar 05, 2021
Content may be subject to copyright.
J.C. Hanekamp 02/03/2021 Page 1
A CRITIQUE ON BURO-REPORT TRCVWA/2021/768 (NVWA)
RISK OF EXPOSURE TO FORMALDEHYDE VIA CHILDREN’S MELAMINE CROCKERY – THE NVWA POSITION WEIGHED
The risks of formaldehyde-exposure to, particularly, toddlers (age 1-3 years) will be considered in the below-
presented evaluation of BuRO-report TRCVWA/2021/768, as it forms the core of that report.
1
Before we commence, however, it must be stated that the BuRO-report cannot be considered a proper risk
assessment. Various aspects of a risk assessment are absent, one of which is a relevant bibliography. Indeed, key
studies are not presented or discussed. The following require, at least, further highlighting:
First, the BuRO-report chooses an unrealistic and inapplicably low 0.025 mg/kgbw/day formaldehyde background
exposure without proper context or elaboration (p.8).
Thus, a factual rationale for a 0.025 mg/kgbw/day formaldehyde background exposure is not presented or
even scientifically validated.
Second, the BuRO-report falsely states that background exposures to formaldehyde, e.g. from foods, that surpasses
the TDI of 0.15 mg/kgbw/day would result in heightened health risks (p.8).
As the TDI is derived from the NOAEL of 15 mg/kgbw/day divided by a 100, this claim is false and without
scientific rationale.
Third, BuRO proposes a lowered Specific Migration Limit (SML) for children of 4.2 mg formaldehyde/kg foods,
based on 300 gr of warm consumables that came into contact with melamine crockery (p.13). BuRO subsequently
concludes that the existing SML of 15 mg formaldehyde/kg is insufficiently protective. This inference is unjustified
as:
1. Migration tests are expressly maximised for leaching formaldehyde from melamine crockery. Warm solid foods
will have a lower migration-potential than a 2h experiment with a 70°C acetic acid 3% watery solution.
2. Migrated formaldehyde into warm solid consumables will bind, to some extent, to food-content chemicals,
making them less biologically available.
3. Formaldehyde migration is limited by the total load present in the melamine crockery. Over time, leaching will
decline to nil so that formaldehyde leaching is not a permanent fixture of melamine crockery use.
4. The TDI derived from Til et al. translates into 32.5 mg/kg food per day (as done by Gelbkea et al.; see below),
which is substantially higher than even the current SML of 15 mg formaldehyde/kg that would need to leach
into warm consumables in contact with melamine crockery.
5. The scientifically unmotivated and arbitrarily low formaldehyde background exposure unrealistically
emphasises formaldehyde migration levels from melamine crockery.
6. The disregarded high natural endogenous production turnover of formaldehyde unrealistically emphasises
formaldehyde migration levels from melamine crockery.
Summarising, NVWA’s assessment of the risks of formaldehyde exposure from melamine crockery is biased, lacks
thoroughgoing analysis -e.g. no exposure assessment from foods is presented- and neglects important and recent
literature. This bias is exacerbated by choosing unrealistically low formaldehyde background exposures from
foods and discounts the substantial endogenous formaldehyde production. As a result, unrealistic and unfounded
worst-case scenarios are pandered to regulators and the media.
The proposed ban and the recommendation are archetypal precautionary responses superficially donned in
toxicological vernacular, inexcusably publicising fear towards the general public. The latter, as a result of the former
two, has no basis in the known physiology and toxicology of formaldehyde, establishing BuRO’s report to be
incompatible with the known science of formaldehyde.
1
This is easily inferred from the following conclusory remark (p.15): “De bevindingen en conclusies over migratie van formaldehyde en
melamine uit bamboe/melamine FCM, zijn ook van toepassing op melamine FCM.”
J.C. Hanekamp 02/03/2021 Page 2
NATURAL FORMALDEHYDE IN FOODS AND PHYSIOLOGY
Formaldehyde is a ubiquitously present chemical in the human and natural environment.
2
Formaldehyde is used
in a variety of industries, including the medical, detergent, cosmetic, food, rubber, fertilizer, metal, wood, leather,
petroleum, and the agricultural.
3
Before we continue, it should be noted beforehand that formaldehyde is produced endogenously in humans as a
result of many different physiological processes. A daily turnover of formaldehyde in humans is estimated to be
between 878-1310 mg/kgbw (kg bodyweight) per day (assuming a half-life of only minutes).
4
Considering this high metabolic turnover, formaldehyde does not accumulate in the body. Human physiology is
well-equipped to deal with large loads of formaldehyde. Exposure to formaldehyde via foods is only relevant, if at
all, to the direct points of contact in the gastro-intestinal tract.
A myriad of foodstuffs naturally contain formaldehyde. Fruit and vegetables contain roughly between 3 and 60
mg/kg product.
5
Cow’s milk can contain up to 3.3 mg/kg product. Meats contain between 0.1 – 20 mg
formaldehyde/kg, beef sitting at the lower end of the scale and pork at the higher end.
6
Fish of different varieties, its consumption generally regarded as adding to a healthy diet, contain between roughly
1–293 mg/kg. Cod, haddock, whiting and other fish belonging to the Gadidae family show the highest
concentrations, even after roasting or boiling.
7
Below, an overview of the formaldehyde content of some fruits and vegetables is presented:
8
2
World Health Organization (WHO). 2002. Concise International Chemical Assessment Document 40: Formaldehyde. WHO, Geneva.
3
World Health Organization (WHO). 1989. Environmental Health Criteria 89, Formaldehyde.
4
European Food Safety Authority (EFSA). 2014. Endogenous formaldehyde turnover in humans compared with exogenous contribution from
food sources. EFSA Journal 12(2): 3550.
5
Nowshad, F., Islam, M.N., Khan, M.S. 2018. Concentration and formation behavior of naturally occurring formaldehyde in foods. Agriculture
& Food Security 7: 17.
6
Claeys W., Vleminckx, C., Dubois, A., Huyghebaert, A., Ho fte, M., Daenens, P., Schiffers, B. 2009. Formaldehyde in cultivated mushrooms: a
negligible risk for the consumer. Food Additives and Contaminants 26(9): 1265-1272.
7
Bianchi, F., Careri, M., Musci, M., Mangia. A. 2007. Fish and food safety: Determination of formaldehyde in 12 fish species by SPME extraction
and GC–MS analysis. Food Chemistry 100: 1049 – 1053.
8
Note 5.
J.C. Hanekamp 02/03/2021 Page 3
NATURAL FORMALDEHYDE AND TODDLER’S (1-3 YEARS) FOOD INTAKE
Considering childrens diets (1-3 years old) will give us a taste of the natural exposure to formaldehyde for the
population group deemed to be one of the most vulnerable.
9
The sampling below will not be exhaustive but will
give a ballpark estimate of exposure.
Total food-intake is estimated at 114.4 g/kgbw per day by the European Food Safety Authority (EFSA). For dietary
exposure assessments, a body weight of 12 kg should be used as default for European toddlers (1-3 years).
10
A toddler consuming ‘one piece of fruit’ or a mixture thereof per day -e.g. made form apples, grapes, bananas or
pears, weighing in at some 200 gr., would amount to a formaldehyde intake between ± 2.0 – 11.6 mg.
Vegetables, say some 150 gr., per day, would add to this intake between ± 1.0 – 5.6 mg of formaldehyde.
Some 100 gr. of meat will add up to ± 2 mg of formaldehyde to the toddler’s intake.
Formaldehyde concentrations in fresh and frozen fish vary widely.
11
Consumption of 100 gr of fish, instead of meat,
could add to the overall intake between ± 0.1 mg – 29 mg/day. To be sure, the higher values will be less likely, but
are certainly not impossible considering the popularity of e.g. cod and haddock.
Fresh dairy products will add little to the formaldehyde intake, and will not be considered here. Also, bread and
related products such as crackers are not considered.
Even this cursory glance at a toddler’s diet shows that natural formaldehyde intake via foods is, on average, at least
± 10 mg per day. This number, again, should be understood as a ballpark figure.
NATURAL FORMALDEHYDE AND ITS RISKS
According to EFSA, exposure to formaldehyde from dietary sources will not exceed 100 mg formaldehyde per day
when no more than 1 kg of food per day is consumed.
12
EFSA, subsequently, considers daily intake to be
approximately 1.4 – 1.7 mg/kgbw.
13
Considering the daily food intake of toddlers, which is one of the highest intakes of any age,
14
the formaldehyde
exposure from food would be around ± 0.8 mg/kgbw for an average (European) toddler weighing 12 kg.
The work of Til et al. is widely referred to with respect to the risk-threshold of formaldehyde exposure, specifically
related to point-of-contact tissue irritation in the gastro-intestinal tract.
15
Very briefly, formaldehyde was administered in drinking-water to groups of 70 male and 70 female Wistar rats for
up to 24 months. Survivors of subgroups of ten rats/sex/group each were killed after 12 or 18 months. The mean
formaldehyde doses administered were 0, 1.2, 15 or 82 mg/kgbw/day for males, and for females the doses were
0, 1.8, 21 or 109 mg/kgbw/day. The authors observations were (italics added):
“Oral administration of formaldehyde at doses of 82 and 109 mg/kg/day to male and female rats, respectively, caused
severe damage to the gastric mucosa but did not result in gastric tumours or tumours at other sites. The study did not
provide any evidence of carcinogenicity of formaldehyde after oral administration. … The general health and behaviour
of the animals did not appear to be affected by any of the formaldehyde treatments. … There was no toxicologically
significant difference in mortality between controls and treated animals ….”
Til et al. determined the formaldehyde No-Observed-Adverse-Effect Level (NOAEL; keeping in mind the sizeable
jump between the NOAEL and the highest experimental dose applied) to be 15 and 21 mg/kgbw/day for male and
female rats, respectively.
16
9
See e.g. https://www.voedingscentrum.nl/nl/zwanger-en-kind/dreumes-en-peuter/voorbeelddagmenu-voor-dreumes-en-peuter.aspx
(last accessed on the 20th of February 2021. Amusingly, this page shows children’s food presented on melamine crockery!);
https://www.healthychildren.org/English/ages-stages/toddler/nutrition/Pages/Sample-One-Day-Menu-for-a-Two-Year-Old.aspx (last
accessed on the 20th of February 2021).
10
European Food Safety Authority (EFSA). 2012. Guidance on selected default values to be used by the EFSA Scientific Committee, Scientific
Panels and Units in the absence of actual measured data. EFSA Journal 10(3): 2579.
EFSA Scientific Committee
11
Note 7.
12
Note 4.
13
Note 4.
14
Note 10.
15
Til, H.P., Woutersen, R.A., Feron, V.J., Hollanders, V.H.M., Falke, H.E., Clary, J.J. 1989. Two-year drinking-water study of formaldehyde in rats.
Food and Chemical Toxicology 27: 77 – 87.
16
Note 15.
J.C. Hanekamp 02/03/2021 Page 4
The NOAEL of 15 mg/kgbw/day was chosen to formulate the human oral Tolerable Daily Intake (TDI) for
formaldehyde: 0.15 mg/kgbw.
17
The TDI is derived from the NOAEL of 15 mg/kgbw/day divided by a factor of
100.(
18
)
However, Gelbkea et al.
19
used the NOAEL of Til et al. to calculate the actual drinkingwater concentrations of
formaldehyde that were fed to the rats in their experiment. Gelbkea et al. state:
“After 2 years of exposure the NOAEL for irritation in the stomach was 15 mg/kg bw/d for males and 21 mg/ kg bw/d
for females, corresponding to 260 mg/l drinking water on average (Til, 1989).”
From this average of 260 mg/l drinkingwater that corresponds to the NOAEL dose, Gelbkea et al., proposed a safe
exposure level of formaldehyde via foods, which they calculated to be at 32.5 mg/kg food per day.
A toddler’s dietary formaldehyde intake, which was found to be a ballpark 10 mg per day, is thus well below the TDI
of 32.5 mg formaldehyde/kg food per day.
Even when considering the fact that toddlers have among the highest food intakes of all human age groups -114.4
g food/kgbw/day,
20
which could possibly result in a somewhat higher formaldehyde intake per day than
approximated above, that still would be below the safe food exposure as proposed by Gelbkea et al.
Additional migrated formaldehyde in warm foods from melamine crockery, even at the SML maximum of 15 mg
formaldehyde/kg, would still be below the 32.5 mg formaldehyde/kg food per day.
It is clear that exposure to formaldehyde at the levels encountered in foods, including additional
formaldehyde migrated from melamine crockery, does not pose a hazard to health, both for children and
adults. This is most clearly understood bearing in mind the natural and other daily intake of formaldehyde
via the diet that is roughly 0.1 – 0.2 % of the natural endogenous formaldehyde production turnover in
humans.(
21
)
17
Note 15.
18
Although not germane to this analysis, the guideline for exposure through inhalation is set at 0.1 mg/m3 based on sensory irritation. See
World Health Organization (WHO). 2010. WHO guidelines for indoor air quality: selected pollutants. Geneva, Switzerland.
19
See Gelbkea, H.-P., Buist, H., Eisert, R., Leibold, E., Sherman, J.H. 2019. Derivation of safe exposure levels for potential migration of
formaldehyde into food. Food and Chemical Toxicology 132, 110598.
20
Note 10.
21
The weight of evidence indicates that formaldehyde is not carcinogenic via the oral route.
World Health Organization (WHO). 2004. Guidelines for Drinking-water Quality. Volume 1. Geneva, Switzerland, p. 378.
J.C. Hanekamp 02/03/2021 Page 5
Dr. Jaap C. Hanekamp Jr. received his degree in chemistry at Utrecht University, The Netherlands, in 1989. He received his first
Ph.D, also in chemistry, from the same institution in 1992, and completed his post-doctoral degree in chemistry at the
University of California Riverside. Dr. Hanekamp received his second Ph.D. in philosophy and theology at the University of
Tilburg, The Netherlands, in 2015. Since receiving his advanced degree in chemistry, Dr. Hanekamp has served on scientific
review committees tasked with auditing the scientific quality of work performed by various Dutch national public health and
environmental agencies, and has also served as a scientific auditor mediating between various Dutch and European industries
and Dutch and European governmental institutions on scientific and legislative issues, and has prepared reports based on his
findings. In 2019-2020 he was a member of the ‘Adviescollege Meten en Berekenen Stikstof’.
Since 2007, Dr. Hanekamp has been an Associate Professor at the University College Middelburg in The Netherlands, where he
teaches chemistry and other tracks. Also since 2007, Dr. Hanekamp has been Director of HAN-Research, an independent
scientific research company that is involved in the evaluation of food, chemical and product safety from a toxicological
perspective, and public health and environmental issues. Since 2011, Dr. Hanekamp has also served as Adjunct Faculty Member
at the University of Massachusetts Amherst, in the department of Public Health and Environmental Health Sciences. Dr.
Hanekamp is the author of numerous articles published in international peer-reviewed scientific journals with a selection
shown below:
J.C. Hanekamp, A. Bast, 2015. Antibiotics exposure and health risks: Chloramphenicol. Environmental Toxicology and
Pharmacology 39(1): 213–220.
J.C. Hanekamp, A. Bast, E.J. Calabrese, 2015. Nutrition and health – transforming research traditions. Critical Reviews in Food
Science and Nutrition 55(8): 1074–1080.
E.J. Calabrese, D.Y. Shamoun, J.C. Hanekamp, 2015. Cancer risk assessment: Optimizing human health through linear dose–
response models. Food and Chemical Toxicology 81: 137–140.
A. Bast, J.C. Hanekamp, 2017. Toxicology: What Everyone Should Know. Academic Press.
J.C. Hanekamp, E.J. Calabrese, 2020. Shaking off the Linear Regulatory Constraints on Human Health. In: Sholl, J., Rattan, S.I.S.
Explaining Health Across the Sciences. Springer.
See further https://www.researchgate.net/profile/JC_Hanekamp
https://jaaphanekamp.com
Dr. Jaap C. Hanekamp, HAN-Research