Pool Water Chemistry Research Articles

Occurrence of bromide and bromate in chlorinated indoor swimming pools, and associated health risks

Swimming is a physical activity that is accessible to people of all ages in all seasons. However, continuous organic and inorganic precursor load and disinfectant dosing make pool water chemistry much more complex than other disinfected waters. Carcinogenic bromate compound is one of the hundreds of disinfection by-products in pool water. The occurrence of bromate in pool waters depends on the precursor content of filling water, the disinfection process, operating parameters, and the purity of disinfectants. While the average filling water bromide concentrations of University Campus indoor swimming pool in Gülbahçe –Urla (SP1) and Buca public indoor swimming pool (SP2) were determined to be 182 μg/L and 11.0 μg/L, respectively, the average bromate concentrations of SP1 and SP2 were 59.4 μg/L and 68.3 μg/L. Estimated chronic-toxic health risks of accidental ingestion of pool water during swimming (between 10-3 and 10-1) were lower than the threshold level (‘1’). Although the carcinogenic risks in central tendency scenario (

Carbon concentrations in natural and restoration pools in blanket peatlands

AbstractOpen‐water perennial pools are common natural features of peatlands globally, and peatland restoration often results in new pool creation, yet the concentrations of different forms of aquatic carbon (C) in natural and artificial restoration pools are not well studied. We compared carbon concentrations in both natural pools and restoration pools (4–15 years old) on three blanket peatlands in northern Scotland. At all sites, restoration pools were more acidic and had mean dissolved organic carbon (DOC) concentrations in restoration pools of 23, 22, and 31 mg L−1 compared with natural pool means of 11, 11 and 15 mg L−1 respectively across the three sites. Restoration pools had a greater fulvic acid prevalence than the natural pools and their DOC was more aromatic. Restoration pools were supersaturated with dissolved CO2 at around 10 times atmospheric levels, whereas for natural pools, CO2 concentrations were just above atmospheric levels. Dissolved CH4 concentrations were not different between pool types, but were ~200 times higher than atmospheric levels. Regular sampling at one of the peatland sites over 2.5 years showed that particulate organic carbon (POC) concentrations were generally below 7 mg L−1 except during the warm, dry summer of 2013. At this regularly‐sampled site, natural pools were found to process DOC so that mean pool outflow concentrations in overland flow were significantly lower than mean inflow DOC concentrations. Such an effect was not found for the restoration pools. Soil solution and pool water chemistry, and relationships between DOC and CO2 concentrations suggest that different processes are controlling the transformation of C, and therefore the form and amount of C, in natural pools compared to restoration pools.

Environmental controls of C, N and P biogeochemistry in peatland pools

Pools are common in northern peatlands but studies have seldom focused on their nutrient biogeochemistry, especially in relation to their morphological characteristics and through seasons. We determined the environmental characteristics controlling carbon (C), nitrogen (N) and phosphorus (P) biogeochemistry in pools and assessed their evolution over the course of the 2016 growing season in a subboreal ombrotrophic peatland of eastern Canada. We showed that water chemistry variations in 62 pools were significantly explained by depth (81.9%) and the surrounding vegetation type (14.8%), but not by pool area or shape. Shallow pools had larger dissolved organic carbon (DOC) and total nitrogen (TN) concentrations and lower pH than deep pools, while pools surrounded by coniferous trees had more recalcitrant DOC than pools where vegetation was dominated by mosses. The influence of depth on pool biogeochemistry was confirmed by the seasonal survey of pools of different sizes with 47.1% of the variation in pool water chemistry over time significantly explained. Of this, 67.3% was explained by the interaction between time and pool size and 32.7% by pool size alone. P concentrations were small in all pools all summer long and combined with high N:P ratios, are indicative of P-limitation. Our results show that pool biogeochemistry is influenced by internal processes and highlight the spatial and temporal heterogeneity of nutrient biogeochemistry in ombrotrophic peatlands.

Trends in temporary pool water chemistry and branchiopod communities along a longitudinal climate gradient in the Nebraska Sandhills

Temporary pools are the most abundant insular aquatic habitats in the world and are ideal systems for studying ecological and evolutionary processes; however, they are poorly studied in many regions of the world in favor of larger, permanent systems like lakes and rivers. The Nebraska Sandhills, Nebraska, USA, contains thousands of groundwater-fed lakes and temporary pools, ranging from freshwater to hypersaline-alkaline. Much of the variation in water chemistry is associated with a longitudinal climate gradient where the climate is mesic in the eastern Sandhills and transitions to semiarid in the western Sandhills. Our objective was to conduct a survey of the temporary pools to learn more about their environmental and ecological characteristics and how they differ along the longitudinal climate gradient. We sampled 30 pools from 3 areas along the climate gradient from April to July 2013. Branchiopod crustaceans were used to measure ecological characteristics because they are adapted to live in temporary pools and are sensitive to environmental changes. The frequency and salinity of saline pools increased westward as aridity increased. Salinity was the primary environmental gradient structuring branchiopod communities. Freshwater alpha and gamma diversity declined westward, which may be due to the westward decline in freshwater habitat. The transition from a homogeneous freshwater-dominated landscape in the eastern Sandhills to a heterogeneous landscape consisting of fresh-, low-, and high-salinity waters in the western Sandhills makes this system ideal for studying ecological processes at local and regional scales.

Occurrence, origin, and toxicity of disinfection byproducts in chlorinated swimming pools: An overview.

Disinfection treatments are critical to conserve the microbiological quality of swimming pool water and to prevent water-borne infections. The formation of disinfection byproducts (DBPs) in swimming pools is an undesirable consequence resulting from reactions of disinfectants (e.g. chlorine) with organic and inorganic matter present in pool water, mainly brought by bathers. A considerable body of occurrence studies has identified several classes of DBPs in swimming pools with more than 100 compounds detected, mainly in chlorinated freshwater pools. Trihalomethanes (THMs), haloacetic acids (HAAs), haloacetaldehydes (HALs) are among the major DBPs in swimming pools. Other DBPs such as haloacetonitriles (HAN), haloamines, nitrosamines, and halobenzoquinones have also been detected. Researchers have been interested in identifying the precursors responsible for the formation of DBPs. In swimming pools, anthropogenic organic loads brought by swimmers increase the complexity of pool water chemistry. When human inputs (e.g. sweat, urine, hair, skin and personal care products) containing very diverse organic compounds are introduced to pools by swimmers, they react with chlorine resulting in the formation of complex mixtures of DBPs. The overwhelming majority of the total organic halide (TOX) content is still unknown in swimming pools. Exposure of swimmers to DBPs can take place through multiple routes, depending on the chemical properties of each DBP. Toxicological studies have shown that swimming pool water can be mutagenic with different potencies reported in different studies. Many DBPs have been shown to be genotoxic and carcinogenic. DBPs were also shown to induce reproductive and neurotoxic adverse effects in animal studies. Epidemiologic studies in humans have shown that exposure to DBPs increases the risk of respiratory adverse effects and bladder cancer. Association between DBPs and other health effects are still inconclusive. Data gathered in the present review (occurrence, toxicity, and toxicological reference values) could be used in conducting chemical risk assessment studies in swimming pools.

Regional variation in the biogeochemical and physical characteristics of natural peatland pools

Natural open-water pools are a common feature of northern peatlands and are known to be an important source of atmospheric methane (CH4). Pool environmental variables, particularly water chemistry, vegetation community and physical characteristics, have the potential to exert strong controls on carbon cycling in pools. A total of 66 peatland pools were studied across three regions of the UK (northern Scotland, south-west Scotland, and Northern Ireland). We found that within-region variability of pool water chemistry was low; however, for many pool variables measured there were significant differences between regions. PCA analysis showed that pools in SW Scotland were strongly associated with greater vegetative cover and shallower water depth which is likely to increase dissolved organic carbon (DOC) mineralisation rates, whereas pools in N Scotland were more open and deeper. Pool water DOC, particulate organic carbon and dissolved CH4 concentrations were significantly different between regions. Pools in Northern Ireland had the highest concentrations of DOC (mean=14.5mgL−1) and CH4 (mean=20.6μgCL−1). Chloride and sulphate concentrations were significantly higher in the pools in N Scotland (mean values 26.3 and 2.40mgL−1, respectively) than elsewhere, due to a stronger marine influence. The ratio of UV absorbance at 465nm to absorbance at 665nm for pools in Northern Ireland indicated that DOC was sourced from poorly humified peat, potentially increasing the bioavailability and mineralisation of organic carbon in pools compared to the pools elsewhere. This study, which specifically aims to address a lack of basic biogeochemical knowledge about pool water chemistry, clearly shows that peatland pools are highly regionally variable. This is likely to be a reflection of significant regional-scale differences in peatland C cycling.

Effect of Road Proximity on Reproductive Effort and Movement Patterns of the Wood Frog (Rana sylvatica)

ABSTRACT Nearly half of the amphibian species in northeastern North America rely on vernal pools as their primary breeding habitat. The problem is that, because vernal pools are small and isolated, they are often left unmonitored and unprotected. A primary threat to both amphibians and vernal pools is habitat destruction and fragmentation, but our knowledge of the species-specific impacts of habitat loss and fragmentation on all phases of the amphibian life cycle are still rudimentary. The wood frog (Lithobates sylvaticus) was the focus of this research because it is considered the most common vernal pool indicator in Pennsylvania. The objectives of this study were to investigate the effect of road proximity on vernal pool hydrology and water chemistry, reproductive effort of wood frogs (i.e., numbers of egg masses deposited), and upland movement patterns of wood frogs. These parameters were compared between three isolated pools (> 1000 m from the nearest road) and two pools in a fragmented habitat (< 100 m from two roads) within a Pennsylvania state park. This study indicates that, although road proximity did not have a significant effect on vernal pool water chemistry and egg mass abundance was greater in the fragmented location, habitat fragmentation by roads did have a significant effect on the movement patterns of wood frogs in surrounding terrestrial habitat. At the isolated site where there were no barriers to movement, wood frogs were distributed randomly around the pools. However, wood frogs in the fragmented location were trapped at a lower frequency near roads than expected by chance, indicating that the presence of roads may reduce the amount of upland habitat utilized by adult wood frogs. Although this was a small and localized study, the results indicate the challenging nature of conserving species with complex life cycles in human dominated landscapes and highlight the importance of considering life-cycle and species-specific habitat requirements when designing vernal pool conservation plans.

Accuracy of swimming pool test kits


 Background: Pool Chemistry is important to allow those using it to feel comfortable through pool water being physically clean and biologically safe. Operators and health inspectors use test kits to ensure that pool water chemistry is correct and will not cause irritation or problems to both the patrons and the pool recirculation system. This study investigates the accuracy of the three commonly used pool test kits available in the market (Taylor, HACH, and ColorQ). Parameters tested are Free Available Chlorine (FAC), Total Chlorine (TC), and pH. Methods: Using artificial pool water with known concentrations of FAC, TC, and pH, 30 samples were taken for the three different parameter from the three test kits. The indicated concentrations and pH on the test kits were then recorded and used to compare with the known standards. Results were analyzed using the statistical software NCSS. One sample t-tests were performed to indicate whether or not the test kit as accurate in reading different parameters of pool chemistry. Results: Taylor Test Kit: Readings for FAC (2.6ppm) showed 2.4ppm, TC (2.7ppm) showed 2.43ppm, and pH (7.1) showed 7.1. HACH Test Kit: Readings for FAC (2.8ppm) showed 3.5ppm, TC (3.0ppm) showed 3.5ppm, and pH (7.1) showed 6.97. ColorQ Test Kit: Readings for FAC (2.7ppm) showed 3.0ppm, TC (3.0ppm) showed 3.0ppm, and pH (7.0) showed 6.96. Conclusion: All three test kits have accurate readings for pH levels. However, the test kits do not provide accurate readings for FAC and TC which would make it difficult to calculate CC in pool waters. Although the FAC and TC readings are inaccurate, they are able to provide operators and health inspectors with brief information regarding pool water chemistry.

Disinfection by-product dynamics in a chlorinated, indoor swimming pool under conditions of heavy use: National swimming competition

Anecdotal evidence suggests that water quality in chlorinated, indoor pools deteriorates under conditions of heavy use. However, data to define these dynamics have not been reported. To address this issue, a study was performed in which water chemistry was monitored in a chlorinated, indoor pool before and during a national swimming competition, a period of heavy, intense use. NCl 3 concentration was observed to double after the first day, and increased by a factor of 3–4 over the 4 days of competition. CNCHCl 2 and CH 3NCl 2 concentrations both increased by a factor of 2–3 during the course of the meet, while CHCl 3 concentration showed only a modest increase during this same period. Diurnal patterns of NCl 3, CH 3NCl 2 and CHCl 3 concentrations were observed, and these patterns appeared to depend on the Henry’s law constant of the compound. Urea concentration showed a diurnal pattern, superimposed on a trend of steady increase during each day of the competition; however, the diurnal pattern of urea behavior could not be explained by reactions with chlorine, as the urea-free chlorine reaction is relatively slow. It is more likely that the overnight decrease in urea concentration was attributable to mixing of surface water with water in the deeper parts of the pool. The findings of this study provide an indication of the changes in pool water chemistry that take place in a chlorinated, indoor pool under heavy use conditions.

Hydrological processes and chemical characteristics of low-alpine patterned wetlands, south-central New Zealand

Summary Patterned wetlands in New Zealand are not only rare, but they are distinguished from their Northern Hemisphere counterparts by their vegetation and the supply of rainfall which is relatively free of pollution. Hydrological processes in two low-alpine patterned wetlands (5 and 220 ha) on block-faulted uplands in south-central South Island, New Zealand were investigated using hydraulic head gradients, and chemical and isotope data. There was no significant spatial variability in chemical parameters within either wetland, although the larger wetland is characterised by a lower trophic status than the smaller one. Ca2+ concentrations and pH of surface water of both wetlands are within the range of that of Northern Hemisphere ombrotrophic/mesotrophic bogs and poor fens. Pool water chemistry only partially overlaps with the lower end of the Ca2+ distribution for the Northern Hemisphere wetlands, likely to be caused by the low level of Ca2+ in aeolian dust. The pH in the pools of the small wetland was generally higher, probably as a result of differing organic acid production by the Sphagnum and sedge species, both of which were common and dominant or sub-dominant in the wetlands. Some temporal variability was observed, possibly due to seasonal variations in plant uptake and/or rainfall. A steady increase in Na+ concentrations in the pools over 4 years was tentatively attributed to an excess of supply from rainfall and/or groundwater. Cation and stable isotope data indicate strong evaporation in pools and surface water, despite the high ambient relative humidity, and mixing within the top of the wetland sequence. Stratigraphy indicates that peat formation has been interrupted by flooding or runoff, bringing mineral matter into the wetlands, particularly in the earlier development stages of the larger wetland. The peat sequence is thicker in the smaller wetland, reaching up to 2.8 m, with limited mineral input during wetland development. The relatively low pH and ionic concentrations in the contemporary water and peat sequence of the larger wetland indicate that it has become isolated from runoff and mineral input.

Effects of agricultural land use on water chemistry of mire pools in the Ishikari Peatland, northern Japan

Concomitant with farmland development in the Ishikari Peatland of northern Japan, deterioration of water chemistry has become increasingly evident at mire pools there. Using spatial analysis methods with a geographic information system and a statistical methodology, this study examined the effects of agricultural land use on the pool water chemistry. A water chemistry survey of several pools showed that nitrogen, phosphorus, and suspended-solid concentrations were remarkably higher than those in pools that had been undisturbed or less-disturbed by land-use development. Principal component analysis (PCA) was conducted to summarize water chemistry variables. Correlation analysis was conducted between the principal component (PC) scores and land-use variables to clarify land-use effects. Results of the PCA showed that the water chemistry variances were accounted for by the first two PCs: PC1 included farmland subsurface drainage containing nitrogen, specifically nitrate, and mineral ions; PC2 included farmland surface drainage containing soil particles and ammonium nitrogen. These PC scores were also affected by the number of inflow ditches and the total area of farmland located within the drainage catchment of inflow ditches leading to the pools. Results suggest that farmland subsurface and surface drainage water flowing into the pools degraded the water chemistry. The extent of the effects of drainage water depended on agricultural practices such as fertilizer application and paddy-field puddling (i.e., mechanical homogenization of water-saturated soil). Accordingly, water chemistry of the study pools was affected by agricultural practices and by the amount of farmland in the drainage basin, engendering eutrophication, and the deterioration of water chemistry. Therefore, preservation of water chemistry necessitates changes in agricultural practices, such as improving fertilizer application methods, along with measures related to land-use planning such as changing the drainage ditches’ flow direction.

Peatland Interstitial Water Chemistry in Relation to that of Surface Pools along a Peatland Mineral Gradient

The elemental (including silica (Si), calcium (Ca), magnesium (Mg), manganese (Mn) and iron (Fe)) and nutrient composition of peatland surface pools and concentrations of Ca, Mg, Mn, and Fein peat interstitial waters and surface peat concentrations of oxides of Mn and Fe were determined for 15 peatlands sampled along a mineral gradient. Surface pool concentrations of Si wereca. ten fold less in surface pools of mineral-poor peatlands thanin the mineral rich, supporting the use of this element as an indicator of minerotrophic influence in peatlands. Principle component analysis of surface pool water chemistry parametersdifferentiated mineral-poor and moderately-poor peatlands frommineral-rich peatlands based on the concentrations of Ca, Mgand alkalinity of pools. Several lines of evidence indicated that peatland interstitial waters were important contributors to peatland alkalinity and included; (1) maximum interstitial water concentrations of Ca and Mg correlating with overlying surface pool alkalinity, (2) a negative correlation between interstitial water Ca:Mg ratios and surface pool concentrationsof Si and (3) Ca:Mg ratios of moderately-poor to mineral-poorpeatland interstitial waters approaching the Ca:Mg ratio of rainwater rather than those of bedrock. Interstitial water concentrations of dissolved Mn and Fe correlated with amountsof reducible Fe and Mn (oxides of Fe and Mn) recovered from thepeat/water interface indicating that groundwater inputs areimportant sources of these two elements to fens. As a consequence, for peatlands that are not truly ombrotrophic,groundwater inputs of Mn and Fe may interfere with interpretingpeat metal profiles thought to be due to anthropogenic inputs alone.

Embryonic Survivorship of the Spotted Salamander (Ambystoma maculatum) in Roadside and Woodland Vernal Pools in Southeastern New Hampshire

Embryonic Survivorship of the Spotted Salamander (Ambystoma maculatum) in Roadside and Woodland Vernal Pools in Southeastern New Hampshire