Model chlorination of plant derived phenolic water contaminants with an assessment of their potential toxicity to Escherichia coli

As a safety measure drinking water is often chemically chlorinated to prevent water-transmittable epidemic diseases. However, great concern about routine water chlorination has been expressed, due to the possible chlorination of unwanted aliphatic and aromatic water contaminants. During the annual litter decay a number of phenolic compounds are released into the environment. Previous studies on water courses have shown that five phenolic acids derived from plants predominate. After water chlorination these compounds are likely to become chlorinated with the production of stable organochlorine derivatives. The objective of the present study was to assess the effects of chlorination on seven plant-derived phenolic compounds. The substitution pattern of the parent (non-chlorinated) compounds was correlated to the number of produced chlorophenolic derivatives (structure versus chemical reactivity). The formed chlorophenolic mixtures were applied to Escherichia coli DSM 613 to examine their potential toxic effects. Escherichia coli DSM 613 was used as an indicator of toxicity for environmental pollution.