The POTENTIAL RISK of STORAGE MITES’ ALLERGENS CONTAMINATION of GRAIN in CZECH REPUBLIC

Abstract:
It is well documented that human food infested by mites may cause anaphylaxis. To establish the mite “allergy-risk threshold” in stored grain, we asked how many mites cause allergenic reaction? In literature we found that exposure to more than 100 mites/g-1 dust increases the risk of sensitisation, and 500 mites/g-1 dust increases the risk of acute asthma. Anaphylaxis was observed in concentrations of mites: 5 000 - 140 000 mite/g-1food. Usually 1 kg of grain contains about 9.64 g of dust. Based on the previous data, we estimate the following three levels of “allergy- risk threshold” (ART): (i) 1000 mites/kg-1 grain represents risk of sensitisation, (ii) 5000 mites/kg-1 grain risk of acute asthma, and (iii) 500 000 mites/kg-1 grain risk of anaphylaxis. We analysed 370 samples of stored grain from Czech Republic. The total number of mites was 116,655. The most abundant species were: Tydeus interruptus, Acarus siro, Tarsonemus granarius, Tyrophagus putrescentiae, Lepidoglyphus destructor, andCheyletus eruditus. The distribution of mites abundance was geometric. The mean density per sample was 308 mites per 1 kg grain. Mites were present in 64% of all samples. But the number of samples above the “allergyrisk threshold” was lower: 4% of samples could cause the risk of sensitisation (first ART level), and 0.1% of samples could cause acute asthma attacks (second ART-level).