efsa-opinion-chromium-food-drinking-water

Chromium in food and drinking water
in food supplements could amount to intake levels of 600 g chromium per day that was well above
the levels considered safe by the World Health Organization (WHO) for supplemental intake (i.e.
250 g per day) (WHO, 1996b). The Panel indicated that although the amount of picolinate that would
be consumed as a result of the proposed uses (4300 g per day) would be safe, it could not be
concluded that the use of Cr(III) picolinate was of no safety concern. It was also noted that there were
diverging views and conclusions on the genotoxicity of Cr(III) and therefore its safety needed to be reevaluated.
The EFSA evaluated the safety of chromium picolinate as a source of chromium added for nutritional
purposes to foodstuff in 2010 (EFSA ANS Panel, 2010a). The ANS Panel noted that the genotoxicity
studies suggested that in vitro at high concentrations chromium picolinate might cause DNA damage.
Long-term carcinogenicity studies provided equivocal or no evidence of carcinogenic activity of
chromium picolinate (Stout et al., 2009; NTP, 2010). The Panel noted that the margin of safety
between the No-Observed-Adverse-Effect Level (NOAEL) of 2400 mg/kg b.w. per day chromium
picolinate, resulting from the National Toxicology Programme (NTP) long-term study, equivalent to
2100 mg/kg b.w. per day picolinate, would amount to at least 4 orders of magnitude assuming a
combined intake of picolinate from all sources. The ANS Panel concluded that the use of Cr(III)
picolinate as a source of chromium would not be of concern provided that the amount of chromium
does not exceed 250 g/day as established by WHO for supplemental intake of chromium that should
not be exceeded.
The EFSA evaluated the safety of trivalent chromium as a nutrient added for nutritional purposes to
foodstuffs in 2010 (EFSA ANS Panel, 2010b). On the basis of the analysis of in vivo genotoxicity
assays and long-term carcinogenicity studies, the ANS Panel concluded that the safety of Cr(III) as a
nutrient added to foodstuffs is not of concern, provided that the intake of Cr(III) from these sources
does not exceed 250 μg/day, which is the value established by the WHO for supplemental intake of
chromium. In 2012, the ANS Panel assessed the use of other additives as a source of Cr(III) for
nutritional purposes, namely a cellular bound chromium yeast (EFSA ANS Panel, 2012a) and Cr(III)
lactate tri-hydrate (EFSA ANS Panel, 2012b). In both cases, the opinions did not focus specifically to
the safety of Cr(III) and in line with the EFSA ANS Panel (2010b) opinion concluded that an intake of
Cr(III) from these sources below 250 µg/day was not of concern.
In 2012, the Agency for Toxic Substances and Disease Registry (ATSDR) published a toxicological
profile for chromium in humans and animals. In the case of Cr(III) the studies on oral toxicity were
considered inadequate for establishing the exposure concentrations that are likely to be without
appreciable risk of adverse effects (noncarcinogenic) (minimal risk level, MRL). Little or no
information was identified regarding acute or intermediate-duration oral exposure to Cr(III)
compounds. Several animal studies showed no adverse effects associated with chronic oral exposure to
Cr(III) compounds (chromium acetate, chromium nicotinate, chromium oxide, chromium picolinate)
even at very high daily doses, therefore an MRL was not derived (ATSDR, 2012).
Chromium VI
The US National Institute for Occupational Safety and Health (NIOSH, 2002) considered all Cr(VI)
compounds to be potential occupational carcinogens. Occupational exposure to Cr(VI) compounds is
associated with lung, nasal, and sinus cancer. Other local effects include nasal irritation and ulceration,
and perforation of the nasal septum and eardrum. Dermal exposure to Cr(VI) compounds can cause
skin irritation, ulceration, sensitization, and allergic contact dermatitis.
The WHO guideline value for chromium in water of 0.05 mg/litre appears to have been established in
the first edition of the WHO drinking water guidelines in 1984/85, and the basis for its derivation is
unclear. The second edition (WHO, 1993) and third edition of the guidelines (2003) both noted that
different guideline values for CrIII and CrVI should be derived, but analytical methods favoured a
guideline value for total Cr. They also noted that because of the carcinogenicity of CrVI by the
inhalation route and its genotoxicity, the current guideline value of 0.05 mg/litre had been questioned,
but the available toxicological data did not support the derivation of a new value. As a practical
measure, 0.05 mg/litre, which was considered to be unlikely to give rise to significant risks to health,
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