Occurrence of brominated disinfection by-products in thermal spas

Thermal spas are gaining more and more popularity among the population because they are used for recreational purposes. Disinfecting these baths without losing the health benefits poses a challenge for swimming pool operators. Previous studies have mainly focused on regulated chlorinated DBPs in freshwater pools with no bromide or seawater pools with very high bromide content. Thermal water pools have a low bromide content and in combination with chlorine can lead to chlorinated, brominated and mixed halogenated DBP species. The occurrence of brominated and mixed halogenated DBPs in these types of pools is largely unexplored, with very few or limited studies published on regulated DBPs and even fewer on emerging DBP classes. In the field of swimming pool water disinfection, apart from extensive studies in the field of drinking water disinfection, only a few studies are known in which >39 halogenated and 16 non-halogenated disinfection by-products, including regulated trihalomethanes (THM) and haloacetic acids (HAA), were investigated in swimming pool water. Calculated bromine incorporation factor (BIF) demonstrated that even small amounts of bromide in swimming pool water can lead to a large shift in DBP species towards brominated and mixed halogenated DBPs. Dihaloacetonitriles (DHANs) accounted for >50% of the calculated cytotoxicity and genotoxicity on average. Comparison of the target analysis with the TOX showed that a major part of the measured TOX (69% on average) could be explained by the regulated classes THMs, HAAs, and the unregulated class of HANs. This study aims to help operators of swimming pools with bromide-containing water to gain a better understanding of DBP formation in future monitoring and to fill the knowledge gap that has existed so far on the occurrence of DBPs in thermal water pools.

Evaluation of the benefit of thermal spa therapy in plaque psoriasis: the PSOTHERMES randomized clinical trial

Spa therapy is considered an add-on treatment for psoriasis, but without any objective evaluation in the absence of randomized trials. This multicenter, open-label, randomized trial compared immediate spa therapy versus a control group having usual treatments until study assessments at 4.5 months. Spa therapy was proposed in five French spa resorts with standardized programs. Inclusion criteria were adults with plaque psoriasis, Dermatology Life Quality Index (DLQI) > 10, and stable medical treatment in the last 6 months. The main objective was DLQI ≤ 10 at 4.5 months after inclusion. VQ-Dermato and EQ5D-3L also assessed quality of life (QoL), Perceived Stress Scale (PSS) stress, and visual analogue scales (VAS) pain and pruritus. Between January 2015 and November 2018, 128 patients were randomized to either immediate spa therapy (64) (within 34 days, median) or usual treatments (61) until assessment at 4.5 months. Most were first-time spa users (71.2%). Mean DLQI and Psoriasis Area and Severity Index at inclusion were 16.7 and 10.5, respectively. Immediate spa therapy patients achieved the primary objective for 66.1% [95% CI 52.6% > 77.9%] vs 41.4% [95% CI 28.6% > 55.1%] control group patients (p = 0.007). VQ-Dermato scores and pruritus VAS significantly improved. Outcomes at 12-month follow-up of the immediate spa therapy group showed persistent improvement of DLQI, VQ-Dermato, and pruritus. This randomized controlled trial demonstrated that a cure of spa therapy improves QoL and alleviates certain symptoms of psoriasis, in short and long terms. This justifies its integration in the therapeutic strategies for psoriasis. Trial registration number: ClinicalTrials.gov Identifier: NCT02098213.

Characterization of radon levels in soil and groundwater in the North Maladeta Fault area (Central Pyrenees) and their effects on indoor radon concentration in a thermal spa

Radon levels in the soil and groundwater in the North Maladeta Fault area (located in the Aran Valley sector, Central Pyrenees) are analysed from both geological and radiation protection perspectives. This area is characterized by the presence of two important normal faults: the North Maladeta fault (NMF) and the Tredós Fault (TF). Two primary aspects make this study interesting: (i) the NMF shows geomorphic evidence of neotectonic activity and (ii) the presence of a thermal spa, Banhs de Tredós, which exploits one of the several natural springs of the area and needs to be evaluated for radiation dosing from radon according to the European regulation on basic safety standards for protection against ionizing radiation. The average soil radon and thoron concentrations along a profile perpendicular to the two normal faults - 22 ± 3 kBq·m^-3 and 34 ± 3 kBq·m^-3, respectively - are not high and can be compared to the radionuclide content of the granitic rocks of the area, 25 ± 4 Bq·kg^-1 for ²²⁶Ra and 38 ± 2 Bq·kg^-1 for ²²⁴Ra. However, the hypothesis that the normal faults are still active is supported by the presence of anomalies in both the soil radon and thoron levels that are unlikely to be of local origin together with the presence of similar anomalies in CO₂ fluxes and the fact that the highest groundwater radon values are located close to the normal faults. Additionally, groundwater ²²²Rn data have complemented the hydrochemistry data, enabling researchers to better distinguish between water pathways in the granitic and non-granitic aquifers. Indoor radon levels in the spa vary within a wide range, [7-1664] Bq·m^-3 because the groundwater used in the treatment rooms is the primary source of radon in the air. Tap water radon levels inside the spa present an average value of 50 ± 8 kBq·m^-3, which does not exceed the level stipulated by the Spanish Nuclear Safety Council (CSN) of 100 kBq·m^-3 for water used for human consumption. This finding implies that even relatively low radon concentration values in water can constitute a relevant indoor radon source when the transfer from water to indoor air is efficient. The estimated effective dose range of values for a spa worker due to radon inhalation is [1-9] mSv·y^-1. The use of annual averaged radon concentration values may significantly underestimate the dose in these situations; therefore, a detailed dynamic study must be performed by considering the time that the workers spend in the spa.