Objectives: To analyse and compare the microbiological quality of the water in rehabilitation and recreational swimming pools in Naples, Italy.
Study design: A 2-year survey investigated the microbiological quality of the water in seven recreational and rehabilitation pools, and the findings were compared with local guidelines.
Methods: For each facility, water was sampled at the intake point and at two points inside the pool. Total microbial contamination and Pseudomonas aeruginosa contamination were evaluated.
Results: Microbial mesophilic contamination and P. aeruginosa contamination were found in all seven pools. Microbial mesophilic contamination was more common in recreational pools (3-4.2% samples were above threshold values), probably due to the greater number of bathers. P. aeruginosa was more common in intake water than water inside the pool [mean values of 19.3 and 22.5 colony-forming units (cfu)/ml in recreational and rehabilitation pools, respectively]. A longer period of contact with chlorine and the dilution process may have led to lower levels of P. aeruginosa in the pool water (range 2-15 cfu/ml).
Conclusions: There is a need to improve disinfection and cleaning procedures, with consideration given to the different uses and daily bather loads of each pool type. There is also a need to monitor water quality and to increase users' knowledge and awareness of the risks.