Philippine Journal of Science
153 (1): 133-145, February 2024
ISSN 0031 – 7683
Date Received: 02 Aug 2023
Lead Content in Moringa oleifera Linn. Leaves and Rootzone Soil in the Nine Cities of Cebu Province, Philippines
Yessa Angela C. Rizabal2, Lora Mae G. Villegas2*, Hemres M. Alburo1, Lemuel M. Velasco1, and Rosalyn P. Alburo1
1Biodiversity, Environmental, and Natural Resources Research Center (BENRC), Cebu Technological University Argao Campus, Cebu, Philippines 2Department of Chemistry, University of San Carlos, Cebu City, Philippines
*Corresponding author: lgvillegas@usc.edu.ph
Rizabal YA et al. 2024. Lead Content in Moringa oleifera Linn. Leaves and Rootzone Soil in the Nine Cities of Cebu Province, Philippines. Philipp J Sci 153(1): 133–145. https://doi.org/10.56899/153.01.14
ABSTRACT
Moringa oleifera Linn. (MO) or malunggay is a staple food in the province of Cebu, Philippines. Lead detection in green Moringa is important to safeguard public health by identifying and mitigating the risk of lead contamination, which – when consumed – can cause serious health issues, particularly in vulnerable populations such as children and pregnant women. Moringa leaves were collected from the nine cities of Cebu province –namely, Bogo, Carcar, Cebu, Danao, Lapu-Lapu, Mandaue, Naga, Talisay, and Toledo. In each city, three barangays were identified as sampling sites based on their abundance along the roads. The leaves were washed, air-dried, digested, and were then analyzed in triplicate for lead (Pb) content using atomic absorption spectrophotometry. Percent recovery and standard reference materials (SRM) samples were also performed in triplicate. Results revealed that lead levels present in Moringa leaves samples from 27 barangays had Pb content well above the 2 mg kg–1 and only four barangays out of 27 gave a result higher than the 85 mg kg–1 standard set by the World Health Organization for plants and soil, respectively. Total lead concentration in leaf samples from the different sampling sites ranges from 0.52–19.9 mg kg–1, whereas the lead concentration in soil samples varies from 12.5–3086 mg kg–1. Lead concentrations in leaves exhibit a significant seasonal variation (P = 0.0175), but it did not show any significant correlation with respect to Pb levels in the root zone soil (R = 0.279, P = 0.159), which was consistent with the values obtained in the enrichment factor (EF > 1) of lead in leaves. This implied that the lead in the Moringa leaves was not accumulated from the root zone soil but through direct foliar transfer. Also, Moringa along the roadside and industrial zones are no longer safe for consumption, especially in urban and industrial cities.