OBJECTIVETo elucidate the dietary exposure to deoxynivalenol (DON) and zearalenone (ZEN) from cereal-based products in Chinese populations using the probabilistic assessment approach.

METHODSA total of 292 wheat flours and 347 corn-based products were collected from sampling sites of 107 supermarkets or farmers markets, which were randomly selected from 44 cities of 13 provinces in 2009 by the stratified cluster random sampling method. Then, DON and ZEN contamination levels in these samples above analyzed by UPLC-MS/MS in combination with the food consumption data of 68 959 respondents, who were divided into group 1 aged 3 to 13 years old, and group 2 aged 14 and over 14 years old (≥14 years old), obtained by China National Nutrition and Health Survey in 2002 were investigated. A probabilistic assessment model using Monte Carlo simulation was applied to derive the intake distribution of P(1)-P(99) percentile of dietary exposure to DON and ZEN. Meanwhile, all parameters related to dietary exposure to both toxins were compared with either the provisional maximum tolerable daily intake (PMTDI) of 1 µg·kg(-1)·d(-1) for DON, or the tolerable daily intake (TDI) of 0.25 µg·kg(-1)·d(-1) for ZEN in order to evaluate the risk of dietary intake of two toxins and find the minimum percentile of dietary exposure to these two toxins. The statistical differences of dietary exposure to these two toxins between two groups were achieved by t test.

RESULTSThe detection frequencies of DON in wheat flours and corn-based products were 100% (292/292) and 97.4% (338/347), respectively. A total of 21 out of 639 samples (wheat flours: 5/292, corn-based products: 16/347) were positive for DON at the levels exceeding the Chinese regulatory limit of 1 000 µg/kg for DON. And the detection frequencies of ZEN in wheat flours and corn-based products were 53.4% (156/292) and 87.6% (304/347), respectively.54 out of 347 corn-based products and no wheat flours were positive for ZEN at the levels exceeding the Chinese regulatory limit of 60 µg/kg for ZEN. Meanwhile, the mean values (95% CI) of the P(50), P(75), P(90), P(95), P(97.5) and P(99) percentile of dietary exposure to DON in populations of 3 to 13 years old were 0.170 (0.170-0.171), 0.762 (0.759-0.765), 2.066 (2.038-2.069), 3.515 (3.501-3.530), 5.342 (5.314-5.372), and 9.220 (9.155-9.279) µg · kg(-1)·d(-1), which were higher than those in populations of ≥14 years old (0.131 (0.130-0.131), 0.500 (0.498-0.501), 1.280 (1.276-1.285), 2.138 (2.128-2.14), 3.510 (3.494-3.527), and 5.512 (5.474-5.546) µg·kg(-1)·d(-1)), with t values of 87.19, 163.87, 164.66, 157.78, 105.47 and 96.31, and all P values less than 0.001. And the mean values (95% CI) of the P(50), P(75), P(90), P(95), P(97.5) and P(99) percentile of dietary exposure to ZEN in populations of 3 to 13 years old were 0.001 (0.001-0.001), 0.006 (0.006-0.006), 0.039 (0.038-0.039), 0.101 (0.100-0.101), 0.195 (0.194-0.197) and 0.378 (0.374-0.381) µg · kg(-1)·d(-1), which were also higher than those in populations of ≥14 years old (0.001 (0.001-0.001), 0.004 (0.004-0.004), 0.026 (0.026-0.026), 0.061 (0.060-0.061), 0.115 (0.115-0.116) and 0.232 (0.231-0.235) µg·kg(-1)·d(-1)) with T-values of 151.11, 73.80, 96.81, 100.81, 91.93 and 76.13, and all P values less than 0.001. Besides, the minimum percentile of dietary exposure to DON in populations of 3 to 13 years old and ≥14 years old exceeded the corresponding PMTDI of 1 µg·kg(-1)·d(-1) was found in the probability distribution of P(76) (99% percentile = 1.03 µg·kg(-1)·d(-1)) and P(84) (95% percentile = 1.01 µg·kg(-1)·d(-1)) percentile, respectively. And the minimum percentile of dietary exposure to ZEN in populations of 3 to 13 years old and ≥14 years old exceeded the corresponding TDI of 0.25 µg·kg(-1)·d(-1) was found in the probability distribution of P(97) (95% percentile = 0.25 µg·kg(-1)·d(-1)) and P(98) (90% percentile = 0.26 µg·kg(-1)·d(-1)) percentile, respectively.

CONCLUSIONThe contamination levels of DON and ZEN in wheat flours and corn-based products and the risk of dietary exposure to both DON and ZEN in populations in Chinese populations were at relatively low levels. The dietary exposure to both DON and ZEN in populations of 3 to 13 years old was higher than those in populations of ≥14 years old . Populations of 3 to 13 years old were the populations at the high risk of dietary exposure to both mycotoxins.