Are fumonisins common contaminants in maize foods and enniatins in cereal grains?

Maize and cereal grains are important food matrices for fungal mycotoxins, although contamination levels differ substantially by crop, region, season, processing, and analytical method.

Occurrence and dietary exposure

• Fumonisins: Strong occurrence evidence supports frequent contamination of maize and maize-derived foods. In a Hungarian survey, fumonisin B1 (FB1) was detected in 33/64 maize-flour samples (51.6%), with mean concentrations of 0.17–0.20 mg/kg and a maximum of 1.46 mg/kg; fumonisin B2 was detected less often (9.4%). Maize consumption is a principal dietary source. Estimated combined FB1+FB2 intake reached 0.258 µg/kg body weight/day at the adult 95th percentile and 0.744 µg/kg/day in children; about 1.5% of children exceeded EFSA’s 1 µg/kg/day group tolerable daily intake in the middle-bound estimate.
• Enniatins: These Fusarium-derived mycotoxins occur mainly in cereal grains and cereal foods. EFSA’s assessment included 12,685 analytical results and identified bread and rolls, fine bakery products, and pasta as important dietary contributors. Enniatin B1 has been reported in wheat, barley, oats, rye, and triticale, with higher total enniatin concentrations reported in spring barley and triticale than wheat in one French survey.

Mechanistic and biomonitoring context

• Fumonisin exposure from maize is biologically measurable: a small fraction of ingested FB1 is excreted as free FB1 in urine, making urinary FB1 a marker of recent exposure.
• Enniatins are associated principally with Fusarium avenaceum and F. tricinctum. Enniatin B1 was detected in 94.3% of urine samples in a large biomonitoring study, consistent with widespread exposure, although it cannot identify an individual’s food source or dose.

Bottom line

• The claim is well supported: fumonisins commonly contaminate maize-based foods, while enniatins are established contaminants of cereal grains and cereal-derived products. FB1 and maize are especially relevant for fumonisin exposure; enniatin occurrence is broader across cereals but more variable by crop and growing conditions.