Pesticide Residues in Fruits and Vegetables from Cape Verde: A Multi-Year Monitoring and Dietary Risk Assessment Study

Abstract

Food safety concerns related to pesticide residues in fruits and vegetables have increased globally, particularly in regions where monitoring programs are scarce or inconsistent. This study provides the first multi-year evaluation of pesticide contamination and associated dietary risks in Cape Verde, an African island nation increasingly reliant on imported produce. A total of 570 samples of fruits and vegetables-both locally produced and imported-were collected from major markets across the country between 2017 and 2020 and analyzed using validated multiresidue methods based on gas chromatography coupled to Ion Trap mass spectrometry (GC-IT-MS/MS), and both gas and liquid chromatography coupled to triple quadrupole tandem mass spectrometry (GC-QqQ-MS/MS and LC-QqQ-MS/MS). Residues were detected in 63.9% of fruits and 13.2% of vegetables, with imported fruits showing the highest contamination levels and diversity of compounds. Although only one sample exceeded the maximum residue limits (MRLs) set by the European Union, 80 different active substances were quantified-many of them not authorized under the current EU pesticide residue legislation. Dietary exposure was estimated using median residue levels and real consumption data from the national nutrition survey (ENCAVE 2019), enabling a refined risk assessment based on actual consumption patterns. The cumulative hazard index for the adult population was 0.416, below the toxicological threshold of concern. However, when adjusted for children aged 6-11 years-taking into account body weight and relative consumption-the cumulative index approached 1.0, suggesting a potential health risk for this vulnerable group. A limited number of compounds, including omethoate, oxamyl, imazalil, and dithiocarbamates, accounted for most of the risk. Many are banned or heavily restricted in the EU, highlighting regulatory asymmetries in global food trade. These findings underscore the urgent need for strengthened residue monitoring in Cape Verde, particularly for imported products, and support the adoption of risk-based food safety policies that consider population-specific vulnerabilities and mixture effects. The methodological framework used here can serve as a model for other low-resource countries seeking to integrate analytical data with dietary exposure in a One Health context.

Keywords: Cape Verde; dietary exposure; food safety; fruits; hazard index; monitoring program; pesticide residues; risk assessment; vegetables.

Figure 1

Number of different pesticide active substances detected in fruits (left) and vegetables (right), classified by type of pesticide.

Figure 2

Distribution of active substances detected in fruits and vegetables according to their authorization status under the European Union and considered by the Codex Alimentarius. Each pie chart represents the proportion of authorized and non-authorized substances in each product group by EU and with MRL established by the Codex. MRLs are recommended by the FAO/WHO Joint Meeting on Pesticide Residues (JMPR) and adopted by the Codex Alimentarius; Codex MRLs are often used by countries lacking their own regulatory framework, such as Cape Verde.

Figure 3

Number of pesticide residues per sample (mean values) detected in each type of fruit and vegetable, classified by origin (imported vs. locally produced). Each bar represents a different type of commodity. This figure allows for the visualization of residue distribution among specific products, complementing the overall average values reported in the text (3.33 residues/sample in imported fruits and 0.89 in locally produced vegetables). For fruits, imported and locally produced items are shown separately. For vegetables, only locally produced samples are included due to the limited number of imported samples (n = 6). **** p < 0.0001.

Figure 4

Total concentration of pesticide residues (ng/g) in fruits and vegetables, grouped by pesticide class. Bars represent the total concentrations of acaricides, fungicides, herbicides, and insecticides, as well as the total pesticide load, based on deterministic estimates using medians. This approach reflects the limited granularity of the available consumption data and ensures consistent treatment of censored observations, avoiding artificially inflated variability estimates. For means, SDs, and ranges, see Supplementary Tables S1 and S2. Statistical significance was assessed using the Mann–Whitney U test. Asterisks denote significant differences between food groups (**** p < 0.0001, *** p = 0.0004, ** p = 0.0092), while “n.s.” indicates no significant difference.

Figure 5

Cumulative hazard index for chronic dietary exposure to pesticide residues in fruits and vegetables among adult (upper panel) and child (lower panel) consumers in Cape Verde. The index is expressed as the ratio between estimated exposure (mg/kg bw/day) and the Acceptable Daily Intake (ADI) for each active substance, aggregated by pesticide class. Values are presented separately for fruits and vegetables, and as a combined total. All estimates are based on a deterministic approach using median residue concentrations and fixed consumption values from the ENCAVE 2019 survey, in line with standard practice in low- and middle-income countries. Dispersion metrics are provided in Supplementary Table S6.