Minimization of Imidacloprid Residues in Cucumber and Bell Pepper Through Washing with Citric Acid and Acetic Acid Solutions and Their Dietary Intake Assessment

Figures & data

Figure 1 Standard chromatogram of imidacloprid.

Figure 2 Standard curve of imidacloprid with various concentrations. (Color figure available online.)

Table 1  Pesticide residue level and its reduction of cucumber and bell pepper through washing with organic acid solutions

Treatments	Cucumber (mg / kg)	Reduction (%)	Bell pepper (mg/kg)	Reduction (%)
Control (tap water)	1.92 ± 0.04a	—	1.89 ± 0.061a	—
Citric acid (1.5%)	0.48 ± 0.02e	75.00	1.02 ± 0.031e	46.03
Citric acid (3%)	0.31 ± 0.01g	83.85	0.87 ± 0.040g	53.96
Citric acid (6%)	0.24 ± 0.09h	87.50	0.78 ± 0.028g	58.73
Citric acid (9%)	0.12 ± 0.04j	93.75	0.52 ± 0.019i	72.48
Acetic acid (1.5%)	0.71 ± 0.013c	63.02	1.60 ± 0.058b	15.34
Acetic acid (3%)	0.48 ± 0.026e	75.00	0.95 ± 0.034ef	49.73
Acetic acid (6%)	0.37 ± 0.018f	80.72	0.68 ± 0.024h	64.02
Acetic acid (9%)	0.34 ± 0.018fg	82.29	0.59 ± 0.021i	68.78
Citric acid (0.75%) + Acetic acid (0.75%)	0.99 ± 0.036b	48.43	1.67 ± 0.067a	11.64
Citric acid (1.5%) + Acetic acid (1.5%)	0.53 ± 0.019d	72.39	1.49 ± 0.053c	21.16
Citric acid (3.0%) + Acetic acid (3.0%)	0.32 ± 0.011g	83.33	1.12 ± 0.040d	40.74
Citric acid (4.5%) + Acetic acid (4.5%)	0.17 ± 0.06i	91.14	0.82 ± 0.029g	56.61
Values are triplicates and expressed as mean ± SD. The same letters in a column showed non-significant differences among treatments.

Table 2  Dietary intake assessment of imidacloprid residue level in cucumber and bell pepper after dipping in citric acid and acetic acid solutions

Treatments	Cucumber (mg/kg)	Bell pepper (mg/kg)
Control (tap water)	16.30a	37.61a
Citric acid (1.5%)	4.07e	20.29e
Citric acid (3%)	2.63g	17.3g
Citric acid (6%)	2.03h	15.52g
Citric acid (9%)	1.01j	10.34i
Acetic acid (1.5%)	6.02c	31.84b
Acetic acid (3%)	4.07e	18.90ef
Acetic acid (6%)	3.14f	13.53h
Acetic acid (9%)	3.02fg	11.74i
Citric acid (0.75%) + Acetic acid (0.75%)	8.40b	33.23a
Citric acid (1.5%) + Acetic acid (1.5%)	4.49d	29.65c
Citric acid (3%) + Acetic acid (3%)	2.71g	22.28d
Citric acid (4.5%) + Acetic acid (4.5%)	1.44i	16.31g
Values are triplicates and expressed as mean ± SD. The same letters in a column showed non-significant differences among treatments.