efsa-opinion-chromium-food-drinking-water

Chromium in food and drinking water
between 910 g/day for a typical intake and 1540 g/day for upper intake. Comparing to the
maximum mean dietary exposure to chromium (LB-UB) calculated in the current opinion for adults
(1.2-1.6 g/kg b.w. per day, 86.5-112.6 g/day) the typical exposure due to supplemental intake
would be 8-11 times higher than that obtained from food intake. The exposure from the upper
supplemental intake would also be 8-11 times higher than the maximum dietary exposure (LB-UB) in
the 95 th exposed population (2.0-2.6 g/kg b.w. per day, 144.7-190.2 g/day).
6.2. Exposure to hexavalent chromium via drinking water (water intended for human
consumption and mineral waters)
Reported analytical results for chromium in drinking water were assumed to be all Cr(VI) as explained
in Section 4.2.2.2. For the main scenario on the exposure to Cr(VI), food was excluded. However, in a
further scenario, it was considered that in certain foods prepared with water before their consumption
(such as coffee, tea infusions, and dry infant and follow-on food) an incomplete reduction of the
Cr(VI) present in water into Cr(III) may happen if the foods are ingested immediately after their
preparation. As explained in Section 6.1., the chromium present in water-based foods classified
(following FoodEx classification) as ‘Fruit and vegetable juices’, ‘Soft drinks’ and ‘Alcoholic
beverages’ was assumed to be Cr(III). Therefore, these food groups are not considered in the
estimation of the exposure to Cr(VI).
As carried out with the exposure to Cr(III), the mean and the high (95 th percentile) chronic exposures
to Cr(VI) were calculated separately for each dietary survey using consumption data recorded at the
individual level and for both LB and UB mean concentrations. In most of the reported data on
drinking water, consumption refers to ‘Tap water’ (63.3 %) followed by bottled water (27.7 %).
Minimum, median and maximum exposure estimates across dietary surveys and age groups are
reported in Table 9. Mean chronic exposure values, across the different dietary surveys and age
classes, ranged from 0.7 ng/kg b.w. per day (minimum LB) to 159.1 ng/kg b.w. per day (maximum
UB). The 95 th percentile dietary exposure ranged from 2.8 ng/kg b.w. per day (minimum LB) to
320.2 ng/kg b.w. per day (maximum UB). As observed in Table 9 the maximum exposure to Cr(VI)
through the consumption of drinking water was estimated in the youngest population (‘Infants’ and
‘Toddlers’).
As mentioned for the exposure assessment to Cr(III) via food, the presence of only two surveys for
infants implies that the exposure to Cr(VI) via drinking water in this age class should be cautiously
interpreted. In the two surveys for infants, the reported data on water consumption mostly refer to the
water used to reconstitute infant food (infant and follow-on food) since the consumption data on these
foods were predominantly reported disaggregated. Contrarily, in the toddler population most of the
data on water consumption refer to water consumed as such.
In all other age classes, a broad range of values between minimum LB and maximum UB in the mean
and high exposure calculations is observed. Apart from small variations in the consumption pattern
among surveys, the main reason for this broad range is the difference between LB and UB estimates
for ‘Tap water’ (LB = 0.2 µg/L, UB = 2 µg/L), the type of drinking water mostly reported in the
Comprehensive Database. In addition, in a few dietary surveys only a small number of individuals
reported water consumption since the surveys were mainly focused on nutrient intake (Greece,
Cyprus, Latvia and Hungary where the percentage of consumers was less than 50 %). As a
consequence, the calculated exposure to Cr(VI) via water may have been slightly underestimated in
certain cases, specially for the minimum mean exposure estimates. However, the exposure estimates
for both average population and highly exposed population are adequate for risk characterisation since
consumption values up to 1.5 L in average population and up to 2.5 L for high consumers were
reported across the different surveys and age classes.
EFSA Journal 2014;12(3):3595 56