## 3 Results
### Contamination Grade by Pesticide Residues in Cereals and Legumes  
The contamination grade by three different classes of pesticides (pyrethroids, organophosphorus and organochlorine compounds) was determined on a total of 220 samples of cereals and legumes, 55% of them coming from Italy. As shown in detail in Figure 2, the other foreign countries belong to Central Asia, Eastern Europe, South Africa, and Canada. Central Asia is one of the major players in international wheat production and Kazakhstan is included in the top ten list of wheat-producing countries and grain exporters in the world [31]. Figure 1: Chromatographic separation of a mixed standard solution of (1) tecnazene, (2) \(\alpha\)-HCH, (3) \(\beta\)-HCH, (4) \(\gamma\)-HCH, (5) quintozene, (6) diazinon, (7) chloropyrifos-methyl, (8) heptachlor, (9) pyrimiphos-methyl, (10) malathion, (11) aldrin, (12) fenthion; (13) chloropyrifos; (14) parathion-ethyl, (15) heptachlor exo-epoxide; (16) heptachlor endo-epoxide, (17) chlorfenvinphos, (18) trans-chloradane, (19) \(\alpha\)-endosulfan, (20) cis-chloradane, (21) profenfos, (22) p,p’ DDE, (23) dieldrin, (24) endrin; (25) \(\beta\)-endosulfan, (26) p,p’ DD, (27) triazophos, (28) endosulfan sulfate, (29) p,p’ DDT, (30) phenothrin, (31) pyrazophos, (32) azinphos-ethyl, (33) permethrin, (34) \(\beta\)-cyfluthrin, (35) cypermethrin, (36) fenvalerate, (37) deltamethin at a concentration of 250 \(\mathrm{\SIUnitSymbolMicro L}^{-1}\). IS: internal standard (PCB 209). Star peaks (*a: \(\gamma\)-HCH; *b: pyrimiphos-ethyl; *c: o,p’ DDE; *d: o,p’ DDD; *e: phosmet; *f: coumaphos) are pesticides not included in the present monitoring study. Figure 2: (**A**) Origin of cereal and legume samples collected during the years 2018 and 2019 and (**B**) number of contaminated samples. No trace of pesticides was observed in the analyzed legume samples. Among cereals, the contamination percentage was 7%. Indeed, the presence of one or more pesticides was observed in 18 samples of cereals (16 wheat samples, 1 durum wheat bran sample, and 1 oatmeal sample) at a concentration higher than the corresponding quantification limit, but never exceeding the MRL set by the European Community. Five pesticides, all of them belonging to the class of pyrethroids (cyfluthrin, cypermethrin, deltamethrin, fenvalerate, and phenothrin), were detected in a wheat sample coming from Russia. Nevertheless, this product was compliant with the current EU legislation, since the presence of each of the residues did not exceed the single MRL set for each substance [32]. Analytical results divided by year, type of contaminated sample, and corresponding pesticide level and MRL are displayed in Table 3. PYRs and OPPs were the most present pesticides in cereal samples. The residue of cyfluthrin, deltamethrin, phenothrin, cypermethrin, and fenvalerate (in the class of PYRs) and chlorpyrifos and pirimiphos-methyl (among OPPs) were observed with a concentration content in the range 0.011-0.113 mg kg\({}^{-1}\), rather below their MRLs, ranging from 0.04 to 5.00 mg kg\({}^{-1}\). The most frequently observed residue among the analyzed cereal samples was pyrimiphos-methyl, which was found not only in wheat samples but also in bran and oats. In 2018, the presence of pyrethroids and organophosphorus compounds was observed in the grain matrix alone, while in 2019 two samples of durum wheat bran and oat flakes were found to be contaminated by pyrimiphos-methyl. Figure 2B shows the number of contaminated samples among the analyzed cereals and legumes. A higher number of contaminated samples came from Russia and Canada, with a contamination grade of 23% and 17%, respectively, followed by Moldava with a percentage of contaminated samples equal to 13%. Despite the highest number of analyzed samples coming from Italy and Kazakhstan, their contamination levels resulted quite low, with percentages equal to 9% and 3%, respectively.