The presence of pharmaceutical and personal care products (PPCPs) in water environments has been extensively reported, particularly at trace concentrations in drinking water (DW). Nevertheless, there is a lack of information on the possible effects of the presence of PPCPs on the microbiota of drinking water distribution systems (DWDS). This pioneer study aims to understand the effects of exposure to selected PPCPs (antipyrine-ANTP, caffeine-CAF, carbamazepine-CBZ, clofibric acid-CA, diclofenac sodium salt-DCF, galaxolide-HHCB, ibuprofen-IBP, tonalide-AHTN, tylosin-TY and trimethoprim-sulfamethoxazole-TMP-SMX) on the motility and biofilm formation of Burkholderia cepacia, a bacterium isolated from a DWDS. The effects of PPCPs on the susceptibility of B. cepacia to sodium hypochlorite (NaOCl) and to the antibiotic combination TMP-SMX was also determined. The results demonstrated that inactivation of B. cepacia with NaOCl was more difficult when in the presence of TMP-SMX, ANTP and CAF. Changes were also found on swarming motility. Biofilms formed in the presence of CBZ and TMP-SMX were more susceptible to NaOCl action. The selected PPCPs had no remarkable effects on swimming motility, biofilm production and susceptibility to TMP-SMX. The overall results emphasize that the presence of some PPCPs in DWDS influence bacterial behavior and decrease the efficiency of DWDS disinfection with chlorine, affecting the microbiological safety of the delivered water.

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Achieving microbial compliance during biosolids storage can be complicated by the unpredictable increase of Escherichia coli. Thermal treatment during anaerobic digestion (AD) and the effects of dewatering may be a significant factor contributing to indicator survival. Shear forces present during dewatering may promote cell damage, releasing nutrient for E. coli growth. The effect of cell damage on E. coli survival was assessed in laboratory-scale thermal and physical disruption experiments. E. coli growth curves for disrupted treatments were compared with control conditions and quantified using flow cytometry and membrane filtration techniques. A significant difference (p < 0.05) in the level of damaged cells between control and disrupted conditions was observed. For thermal and physical disruption treatments, the peak of E. coli concentration increased significantly by 1.8 Log and 2.4 Log (CFU (colony forming units) g−1 DS), respectively, compared with control treatments. Research findings contribute to the understanding of bacterial growth and death dynamics in biosolids.