RESUMEN
CONTEXT AND OBJECTIVES: Lead (Pb) toxicity leads to cell damage in many organs of the body. Using different treatment interventions and modes of administration we comparatively examined the protective ability of some medicinal plants on liver Pb accumulation. MATERIALS AND METHODS: Rats were fed on either 7% w/w Zingiber officinale, 7% w/w Allium sativum, 10% w/w Lycopersicon esculentum, 5%, w/w Garcinia kola (all in rat chow), while Pb (100 ppm) was given in drinking water. The additives were administered together with (mode 1), a week after exposure to (mode 2) or a week before metal exposure to (mode 3) the metal for a period of 6 weeks. The metal accumulations in the liver were determined using atomic absorption spectrometry and compared using analysis of variance. RESULTS: Some additives significantly (P < 0.05) reduced, while others enhanced Pb accumulation. Mode 2 yielded the highest mean % protection and mode 3 the lowest, no significant interaction between modes of administration and time of measurement in their relationships to percentage protection, but there was statistically significant (P < 0.05) interaction between modes of administration and additive used in their relationships to percentage protection. CONCLUSION: Protective effects of medicinal plants are varied and depend on the nature of lead exposure.