the formation of renal and urinary calculi is not due to a single cause but occurs as a multifactor entity, by which some of them still are unknown. three theories of stones formation including nucleation, stone matrix and inhibition of crystallization do not accuse water hardness as a main cause of the formation of urinary calculi 120 patients suffering from renal and urinary calculi and the s...

Water hardness is a property depending on the presence of alkaline earth metals, mainly calcium and magnesium. Among the strategies for water quality monitoring, ecotoxicological assays are performed to minimize impacts and classify water bodies. For these laboratory evaluations parameters are previously defined in the guidelines, including water hardness for both cultivation and testing medium...

all aquatic organisms are directly or indirectly affected by the physical characteristics of their environment, especially the chemical composition of the water. the high concentration levels, damage tissues and interfere with the normal growth and proliferation. the aim of this research was to investigation acute toxicity of znso4 and cucl2 to gambusia holbrooki by static bioassays at differen...

The influence of water hardness and dissolved organic matter (DOM) on bioavailability of organic chemicals to Daphnia magna was studied by using benzo[a]pyrene (BaP), pyrene, atrazine, and 3,3',4,4'-tetrachlorobiphenyl (TCB) as model compounds. Two types of DOM were used, namely Lake Kontiolampi, Joensuu, Finland water (KL) and Nordic reference fulvic acid (NoFA) dissolved in artificial freshwa...

The hardness-based regulatory approach for Cu prescribes an extrapolation of the toxicity-versus-hardness relationship to low hardness (< or =50 mg/L as CaCO3). Hence, the objective of the present research was to evaluate the influences of water quality on acute Cu toxicity to larval fathead minnow (Pimephales promelas) in low-hardness surface waters. Seasonal water sampling was conducted at 24...

BACKGROUND Use of alkaline peroxide denture cleanser with different temperature of water could cause a change in surface hardness of the acrylic denture and also has a bleaching effect. The purpose of the study was to determine the effect of increased water content during thermal cycling of hot water-treated acrylic on the surface hardness of acrylic denture base when compared to warm water tre...

The effects of humic acid and water hardness on acute cadmium toxicity and accumulation were determined, using Puntius gonionotus Bleeker. The toxicities were expressed as the median lethal concentration (LC50) and the 96-h LC50 value of cadmium was 2.30 mg/L. Three different types of water hardness were used: soft, moderately-hard and hard, with total hardness concentrations of 55, 113, and 22...

BACKGROUND Numerous studies have suggested an inverse relationship between drinking water hardness and cardiovascular disease. However, the weight of evidence is insufficient for the WHO to implement a health-based guideline for water hardness. This study followed WHO recommendations to assess the feasibility of using ecological time series data from areas exposed to step changes in water hardn...

background:the aim of this study is to investigate the association ofcalcium and magnesium concentration of drinking water with cardiovascular disease (cvds) in urban and rural areas of a city in iran. methods:this case-control study was conducted in 2012 in khansar county in isfahan province, iran. we used the official data of the provincial health center regarding the chemical analysis data o...