What’s in the Pool? A Comprehensive Identification of Disinfection By-products and Assessment of Mutagenicity of Chlorinated and Brominated Swimming Pool Water

38 páginas, 2 figuras, 4 tablas.-- PDF con material suplementario.[BACKGROUND]: Swimming pool disinfectants and disinfection by-products (DBPs) have been linked to human health effects, including asthma and bladder cancer, but no studies have provided a comprehensive identification of DBPs in the water and related that to mutagenicity.[OBJECTIVES]: We performed a comprehensive identification of DBPs and disinfectant species in waters from public swimming pools in Barcelona, Catalonia, Spain, that disinfect with either chlorine or bromine, and we determined the mutagenicity of the waters to compare to the analytical results.[METHODS]: We used gas chromatography (GC)/mass spectrometry (MS) to measure THMs in water and GC with electron capture detection (ECD) for air, low and high resolution GC/MS to comprehensively identify DBPs, photometry to measure disinfectant species (free chlorine, monochloroamine, dichloramine, and trichloramine) in the waters, and an ion chromatography method to measure trichloramine in air. We assessed mutagenicity in the Salmonella mutagenicity assay.[RESULTS]: We identified more than 100 DBPs, including many nitrogen-containing DBPs that were likely formed from nitrogen-containing precursors from human inputs, such as urine, sweat, and skin cells. Many DBPs were new and have not been reported previously in either swimming pool or drinking waters. Bromoform levels were greater in the brominated vs. chlorinated pool waters, but many brominated DBPs were also identified in the chlorinated waters. The pool waters were mutagenic at levels similar to that of drinking water (~1200 revertants/L-eq in strain TA100 –S9 mix).[CONCLUSIONS]: This study identified many new DBPs not identified previously in swimming pool or drinking water and found that swimming pool waters are as mutagenic as typical drinking waters.This research was supported by EPA’s intramural research program and the Spanish grants SAF2005-07643-C03-01 (Plan Nacional) and CP06/00341 (Fondo de Investigación Sanitaria). CMV and LFR have, respectively, a contract and a predoctoral fellowship by the Instituto de Salud Carlos III (CP06/00341, FI06/00651). CL acknowledges a grant from the Agreement between Santander-Central Hispano and CSIC.Peer reviewe

Measurement of Nitrosamine and Nitramine Formation from NO_<i>x</i> Reactions with Amines during Amine-Based Carbon Dioxide Capture for Postcombustion Carbon Sequestration

With years of full-scale experience for precombustion CO₂ capture, amine-based technologies are emerging as the prime contender for postcombustion CO₂ capture. However, concerns for postcombustion applications have focused on the possible contamination of air or drinking water supplies downwind by potentially carcinogenic <i>N</i>-nitrosamines and <i>N</i>-nitramines released following their formation by NO_<i>x</i> reactions with amines within the capture unit. Analytical methods for <i>N</i>-nitrosamines in drinking waters were adapted to measure specific <i>N</i>-nitrosamines and <i>N</i>-nitramines and total <i>N</i>-nitrosamines in solvent and washwater samples. The high levels of amines, aldehydes, and nitrite in these samples presented a risk for the artifactual formation of <i>N</i>-nitrosamines during sample storage or analysis. Application of a 30-fold molar excess of sulfamic acid to nitrite at pH 2 destroyed nitrite with no significant risk of artifactual nitrosation of amines. Analysis of aqueous morpholine solutions purged with different gas-phase NO and NO₂ concentrations indicated that <i>N</i>-nitrosamine formation generally exceeds <i>N</i>-nitramine formation. The total <i>N</i>-nitrosamine formation rate was at least an order of magnitude higher for the secondary amine piperazine (PZ) than for the primary amines 2-amino-2-methyl-1-propanol (AMP) and monoethanolamine (MEA) and the tertiary amine methyldiethanolamine (MDEA). Analysis of pilot washwater samples indicated a 59 μM total <i>N</i>-nitrosamine concentration for a system operated with a 25% AMP/15% PZ solvent, but only 0.73 μM for a 35% MEA solvent. Unfortunately, a greater fraction of the total <i>N</i>-nitrosamine signal was uncharacterized for the MEA-associated washwater. At a 0.73 μM total <i>N</i>-nitrosamine concentration, a ∼25000-fold reduction in concentration is needed between washwater units and downwind drinking water supplies to meet proposed permit limits