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It has already been well established that long exposure to low doses of pesticides is linked to consumer risks. So, this study purposed to investigate the amounts of pesticide residues and potential health risks associated with them. The risk assessment was determined by two methods: 1. Pesticide toxicity index (PTI) depending on the maximum residue limit (MRL) to calculate the hazard quotient (HQ); 2. Health risk assessment (HR) using acceptable daily intake (ADI) and estimated daily intake (EDI) to calculate the health index (HI). Pesticide residues were estimated in 176 samples of the most popularly consumed vegetables collected from major retailers and markets in Dakahlia, Egypt (during 2018). There were 111 samples contaminated with pesticide residues (63.1%), of which 29 samples (16.48%) were higher than the maximum residue limits (MRL). Residues of 23 compounds were found in the analyzed samples, of which chlorpyrifos was the most frequent in 33 samples (18.75%); while cypermethrin was the lowest (detected in one sample). According to WHO toxicity classification, 12 of the detected pesticides were moderately hazardous (class II), seven pesticides belonged to class III (slightly hazardous), three compounds were found in class U (unlikely to pose an acute hazard with normal use), while carbofuran is a highly toxic compound (class Ib). Also, the obtained data revealed that, the HI’s for the individual pesticides ranged from 0.0018 to 64.0% of ADI indicates no risk of adverse effects following exposure to the individual pesticides. The cumulative exposure amounts (PTI values) ranged from 1.58 in snake cucumber to 128.44 in potato tubers, indicating that, the combined risk index of pesticide residues was a significant health risk for consumers according to the individual risk index. It can be concluded that there is a need for strict regulation and regular monitoring of pesticide residues in foodstuff for consumers’ health protection.

In two field experiments, the effect of some weed control treatments (citric acid at the rate of 10, 15 and 20%, acetic acid at the rate of 20, 30 and 40%, oxadiargyl, oxyflurfen, rice straw mulch, hand hoeing and an unweeded check control treatment) on weed growth and onion productivity in sandy soils at the Agricultural Experimental Station of the National Research Centre, Egypt was studied. The results indicated that all weeded treatments reduced the dry weight of broadleaf, grassy and total weeds as compared with the weedy check. Oxadiargyl, followed by two hand hoeing, rice straw mulch and acetic acid 40% recorded the greatest weed control efficiency. Insignificant differences were noticed between these treatments. Applying rice straw mulch increased bulb length, bulb diameter, bulb weight and onion yield by 67.52, 57.55, 45.74 and 66.22% over the weedy check, respectively. The highest values of N, P and K were obtained from rice straw mulch treatment followed by hand hoeing, oxadiargyl and acetic acid 40% treatments. It may be concluded that farmers can certainly depend on mulching or acetic acid at 40% instead of using chemical herbicides especially in organic farm systems for controlling onion weeds.

Two field experiments were established at the Agricultural Experimental Station of the National Research Centre at Nubaria, Beheira Governorate, Egypt to study the herbicidal potential of the leaf extract of Eucalyptus citriodora at 5, 10, 15, 20 and 25% compared to two hand hoeing, unweeded treatments and the chemical herbicides Bentazon + Clethodium, Bentazon + Fluazifop-P-butyl and Butralin on pea plants and associated weeds. The results indicated that two hand hoeing achieved the maximum weed depression as expressed by the dry matter of total weeds. The dry matter of total weeds decreased by 95.08 to 94.77% as compared with unweeded treatment 50 and 70 days after sowing (DAS) followed by Butraline (93.93–94.65%), Bentazon + Clethodium (93.26–94.07%), Bentazon + Fluazifop- -P-butyl (91.82–92.77%) and leaf extract of Eucalyptus at 25% (91.61–91.95%). Furthermore, the reduction in weed development was accompanied by enhanced pea growth and yield. The results revealed that two hand hoeing was the best treatment to increase plant height, shoot dry weight and SPAD value at 50 and 70 DAS. Also, two hand hoeing produced the maximum values of pod length and number of seeds/pod. The results also indicated that Bentazon + Clethodium treatment gave observable values [recorded 72.96% in pod yield (ton ⋅ fed.–1) over that of unweeded control] of number of pod/plant, weight of pod/plant, seed yield/fed and protein percentage. Also, the results revealed great increases in the growth of pea as well as yield due to treatment with E. citriodora dry leaf extract at 25%. [recorded 64.8% in in pod yield (ton ⋅ fed.–1) over that of unweeded control]. So, the results indicated using Bentazon + Clethodium as well as E. citriodora dry leaf extract at 25% to control weeds associated with pea plants. The authors suggested application of E. citriodora dry leaf extract at 25% in controlling weeds associated with pea plants as a safe method that avoids environmental contamination.