Pierluigi Giacobazzi

Prevalence of Ocular, Respiratory and Cutaneous Symptoms in Indoor Swimming Pool Workers and Exposure to Disinfection By-Products (DBPs)

The objective of this cross-sectional study was to investigate the prevalence of self-reported respiratory, ocular and cutaneous symptoms in subjects working at indoor swimming pools and to assess the relationship between frequency of declared symptoms and occupational exposure to disinfection by-products (DBPs). Twenty indoor swimming pools in the Emilia Romagna region of Italy were included in the study. Information about the health status of 133 employees was collected using a self-administered questionnaire. Subjects working at swimming pools claimed to frequently experience the following symptoms: cold (65.4%), sneezing (52.6%), red eyes (48.9%) and itchy eyes (44.4%). Only 7.5% claimed to suffer from asthma. Red eyes, runny nose, voice loss and cold symptoms were declared more frequently by pool attendants (lifeguards and trainers) when compared with employees working in other areas of the facility (office, cafe, etc.). Pool attendants experienced generally more verrucas, mycosis, eczema and rash than others workers; however, only the difference in the frequency of self-declared mycosis was statistically significant (p = 0.010). Exposure to DBPs was evaluated using both environmental and biological monitoring. Trihalomethanes (THMs), the main DBPs, were evaluated in alveolar air samples collected from subjects. Swimming pool workers experienced different THM exposure levels: lifeguards and trainers showed the highest mean values of THMs in alveolar air samples (28.5 ± 20.2 μg/m3), while subjects working in cafe areas (17.6 ± 12.1 μg/m3), offices (14.4 ± 12.0 μg/m3) and engine rooms (13.6 ± 4.4 μg/m3) showed lower exposure levels. Employees with THM alveolar air values higher than 21 μg/m3 (median value) experienced higher risks for red eyes (OR 6.2; 95% CI 2.6–14.9), itchy eyes (OR 3.5; 95% CI 1.5–8.0), dyspnea/asthma (OR 5.1; 95% CI 1.0–27.2) and blocked nose (OR 2.2; 95% CI 1.0–4.7) than subjects with less exposure. This study confirms that lifeguards and trainers are more at risk for respiratory and ocular irritative symptoms and cutaneous diseases than subjects with other occupations at swimming pool facilities.

Airborne trichloramine (NCl 3 ) levels and self-reported health symptoms in indoor swimming pool workers: dose-response relationships

The hypothesis that attendance at indoor chlorinated swimming pool is a risk factor for irritative ocular and respiratory symptoms and bronchial asthma is well known in literature, although epidemiological evidence is still inconclusive. The aim of this study was to evaluate the association between airborne trichloramine (NCl3) levels and irritative symptoms in swimming pool employees in order to obtain detailed data regarding dose-response relationships and to identify the airborne NCl3 exposure level, if any, without health effects. A total of 20 indoor swimming pools in the Emilia Romagna region of Italy were included in the study. Information about the health status of 128 employees was collected using a self-administered questionnaire. Exposure to airborne NCl3 was evaluated in indoor swimming pools by a modified DPD/KI method. The results of the study evidenced a mean value of airborne NCl3 of 0.65±0.20 mg/m3 (ranging from 0.20 to 1.02 mg/m3). Both ocular and upper respiratory symptoms, in particular red eyes, runny nose, voice loss and cold symptoms, were declared more frequently by lifeguards and trainers when compared with employees working in other areas of the facility (office, cafe, and so on). Pool attendants exposed to airborne NCl3 levels of >0.5 mg/m3 experienced higher risks for runny nose (OR: 2.91; 95% CI: 1.22–6.93) red eyes (OR: 3.16; 95% CI: 1.46–6.82), voice loss (OR: 3.56; 95% CI: 1.60–7.95) and itchy eyes (OR: 2.23; 95% CI: 1.04–4.78) than other employees. Moreover, red eyes, itchy eyes, runny nose and voice loss are related to airborne NCl3 levels, with strong dose-response relationships. In conclusion, this study shows that lifeguards and trainers experience ocular and respiratory irritative symptoms more frequently than employees not exposed. Irritative symptoms become significant starting from airborne NCl3 levels of >0.5 mg/m3, confirming that the WHO-recommended value can be considered protective in occupational exposure to airborne NCl3 in indoor swimming pools.

Determination of nitrogen trichloride (NCl3) levels in the air of indoor chlorinated swimming pools: an impinger method proposal

The quality of the environmental air from indoor swimming pools has been associated with various health risks. Particular attention has focused on the effects of chronic lung exposure to chlorine and its by-products, especially in young children. We developed a simple, non-toxic approach to detect and monitor nitrogen trichloride air levels in the indoor swimming pool environment. The proposed Impinger Method (IM) was used to measure the environmental levels of nitrogen trichloride (NCl3) in 17 indoor swimming pools located in Northern Italy. This new analytical protocol is based on a colorimetric reaction commonly employed to detect the total and free chlorine levels in water. Specifically, IM allows the entrapment of NCl3 into a water solution containing diethyl-p-phenylenediamine (DPD 1) and Potassium Iodide (DPD 3). NCl3 from the air environment reacts with DPD 3 releasing iodine, which reacts with DPD 1 and produces a coloration proportional to the amount of NCl3 from the sampled indoor swimming pool air. Our sampling of the monitored swimming pool environments evidenced a mean NCl3 level (637 ± 220 µg/m3) higher than the recommended WHO value (500 µg/m3). The IM was validated in terms of linearity (R 2 = 0.996), limit of detection (3.6 µg/m3) and repeatability (CV = 1.7%), demonstrating easy-to-use characteristics, good efficiency and low cost.