Investigation of the Effect of Twelve Pharmaceuticals on Germination and Growth Parameters of Basil (Ocimum basilicum L.)

Abstract

Pharmaceuticals (PhACs) are chemical substances that, after their use, can reach wastewater treatment plants, but the resulting treated wastewater (TWW) can still contain these contaminants. If TWWs are used for irrigation, PhACs can contaminate crops and also hinder their growth. The aim of this work was to evaluate the effects of 12 PhACs and their mixture at different doses on basil germination and early growth and on its photosynthetic pigment content. The germination percentage was not affected by PhACs even when applied at the highest doses. The results showed that the germination speed cannot be considered as an index of vigor of future seedlings as not all seeds that germinated first developed the best. PhACs between 25 and 100 ppb did not show negative effects on early growth and photosynthetic pigments of basil; in fact, in some cases the seeds even benefitted from their application as if it were a chemical treatment developed for the seeds. The highest assessed dose of PhACs always caused a reduction in growth parameters and the photosynthetic pigment content of basil, especially with climbazole, naproxen, triclosan, and the mixture of PhACs. In general, basil can be considered a species tolerant to PhACs after taking into account their average content in wastewater; however, more studies are needed to evaluate the long-term effects of PhACs and their translocation to edible parts.