Tetracycline residues in organic and commercial eggs in public markets of Davao City, Philippines

Antibiotic residues in food products are a growing public health concern because they contribute to antimicrobial resistance. This study aimed to determine the levels and health risks of tetracycline residues in organic and commercial chicken eggs collected from wet markets in Davao City, Philippines. An Enzyme-linked immunosorbent assay (ELISA) was used to analyze 228 eggs (114 organic and 114 commercial), with sampling conducted in three rounds over one month to capture potential temporal fluctuations. Organic eggs had a mean tetracycline concentration of 18.16±82.5 ng/g, significantly higher than the 1.10±37.2 ng/g observed in commercial eggs (p=0.004). However, nearly all detected residues were below The Bureau of Product Standards maximum residue limit (MRL) of 400 ng/g, with only 1.75% of the organic samples exceeding this threshold. Health risk assessment based on estimated daily intake and hazard quotient showed that all values were well below the acceptable daily intake of tetracyclines and far below 1, indicating no appreciable risk of adverse health effects from dietary exposure to tetracycline residues through egg consumption at current intake levels. However, the higher mean residue levels in organic eggs highlight the need for continuous surveillance and stricter regulation of antibiotic use in poultry production to safeguard food safety and help mitigate the development of antimicrobial resistance.