Brass Fittings Research Articles

Effect of Community Water Service on Lead in Drinking Water in an Environmental Justice Community.

Multiple recent studies have found elevated lead (Pb) concentrations in tap water in U.S. homes relying on unregulated private wells. The main Pb source is dissolution from household plumbing, fixtures, and well components. Here, we leverage a natural experiment and citizen science approach to evaluate how extending community water service to an environmental justice community relying on private wells affects Pb in household water. We analyzed Pb in 260 first-draw kitchen tap water samples collected by individual homeowners over a 5-month period in residences that did and did not connect to the community system. Before the community water system was extended, 25% of homes had Pb > 15 μg/L (the U.S. regulatory action level for community water systems) in first-draw water samples. Pb was significantly correlated with nickel (ρ = 0.61), zinc (ρ = 0.50), and copper (ρ = 0.40), suggesting that corrosion of brass fittings and fixtures is the main Pb source. Among homes that connected to the community system, Pb decreased rapidly and was sustained at levels well below 15 μg/L over the study period. Overall, connecting to the municipal water supply was associated with a 92.5% decrease in first-draw tap water Pb.

Effect of Residual Stress on Cracking of Hot Die-Forged Brass Fittings

Lead brasses, i.e. copper-based alloys with additions of zinc and lead, are widely used for production of specific components in the industry and commerce. Brass components are usually produced under hot conditions, i.e. via hot die forging (with the advantageous applications of induction heating), the semi-products for which are typically rods extruded from cast billets. Finally, the components are machined to their exact shapes. Nevertheless, such a complicated production process is prone to introduce defects in the structures of the final components. The herein presented paper deals with investigations of a brass component (pre-shaped gas valve, i.e. fitting) manufactured via hot die forging. The fitting exhibited cracking in a specific location after forging and the presented investigation attempts to characterize the factors, which could have possibly induced the occurring cracking, from the viewpoint of stress distribution. The experimental investigation focused on characterization of the structure in the vicinity of the cracked area with the particular focus on the occurrence of residual stress via scanning electron microscopy. This analysis was supported with the results of stress-strain distribution during forging acquired via numerical simulation of the die forging processing step (with implemented induction heating prior forging, in accordance with the real industrial conditions) performed using the finite element method (FEM). According to the acquired results, the cracking occurred in a location featuring local inhomogeneity of stress. The inhomogeneous distribution of stress in the particular location most probably developed as the result of the geometry of the forging die, which also introduced instabilities in the material plastic flow during forging.

A Fix for Fixtures: Addressing Lead Contamination in West African Drinking Water.

A Fix for Fixtures: Addressing Lead Contamination in West African Drinking Water.

Widespread nickel contamination in drinking water supplies of elementary schools in Taichung, Taiwan.

Owing to the limited information regarding potential sources of nickel (Ni) in drinking water, incidences of Ni contamination have not been well elucidated in the literature. However, in recent decades, Ni-containing plumbing materials such as stainless steel pipes, brass fittings, and chrome faucets have gained popularity in drinking water distribution systems. As a result of increased use of such materials, Ni levels in drinking water are expected to rise over time, posing long-term exposure risks to consumers. For the first time, this study employed an intensive sequential sampling, from October 2019 to July 2020, to assess Ni levels in drinking water samples collected from dispensers of elementary schools in Taichung, Taiwan. Of the total 580 sequential samples collected from 58 elementary schools, 45 samples from 17 schools exceeded the Taiwan Environmental Protection Administration (EPA) standard value of 20 μg/L for Ni. Total Ni concentration in 1 L sample, an average of the total Ni concentrations in 10 sequential samples, exceeded in 4 schools. This finding suggests minor Ni contamination in drinking water supplies across the city. The highest Ni concentration was measured in the 1st sequential sample reaching 154 μg/L. Weekend and summer samples exhibited a higher tendency to exceed the standard. Older schools with age above 50 years and schools with a higher student population (≥ 500) were more likely to have Ni contamination. This study showed that drinking water is a potential source of Ni. However, the identification of Ni source, whether within the dispenser or in the distribution system, warrants further research.

Structural Factors Inducing Cracking of Brass Fittings.

Cu–Zn–Pb brasses are popular materials, from which numerous industrially and commercially used components are fabricated. These alloys are typically subjected to multiple-step processing—involving casting, extrusion, hot forming, and machining—which can introduce various defects to the final product. The present study focuses on the detailed characterization of the structure of a brass fitting—i.e., a pre-shaped medical gas valve, produced by hot die forging—and attempts to assess the factors beyond local cracking occurring during processing. The analyses involved characterization of plastic flow via optical microscopy, and investigations of the phenomena in the vicinity of the crack, for which we used scanning and transmission electron microscopy. Numerical simulation was implemented not only to characterize the plastic flow more in detail, but primarily to investigate the probability of the occurrence of cracking based on the presence of stress. Last, but not least, microhardness in specific locations of the fitting were examined. The results reveal that the cracking occurring in the location with the highest probability of the occurrence of defects was most likely induced by differences in the chemical composition; the location the crack in which developed exhibited local changes not only in chemical composition—which manifested as the presence of brittle precipitates—but also in beta phase depletion. Moreover, as a result of the presence of oxidic precipitates and the hard and brittle alpha phase, the vicinity of the crack exhibited an increase in microhardness, which contributed to local brittleness.

How to Deal with Uninvited Guests in Wine: Copper and Copper-containing Oxidases

Copper is one of the most frequently occurring heavy metals in must and wine. It is introduced by pesticides, brass fittings, and as copper sulphate for treatment of reductive off-flavors. At higher concentrations, copper has harmful effects on the wine. It contributes to the oxidation of wine ingredients, browning reactions, cloudiness, inhibition of microorganisms, and wine fermentation. Last but not least, there is also a danger to the consumer. At present, some physicochemical methods exist to reduce the copper content in must and wine, but they all have their shortcomings. A possible solution is the biosorption of metals by yeasts or lactobacilli. Copper can also reach must and wine in the form of copper-containing phenol oxidases (grape tyrosinase, Botrytis cinerea laccases). Similar to free copper, they oxidize phenolic wine compounds, and thus lead to considerable changes in color and nutritional value, making the product ultimately unsaleable. All measurements for enzyme inactivation such as heat treatment, and addition of sulphites or bentonite are either problematic or not effective enough. The application of oenological tannins could offer a way out but needs further research.

Public Health Risks Associated with Heavy Metal and Microbial Contamination of Drinking Water in Australia.

Recently in Australia concerns have been raised regarding the contamination of municipal drinking water supplies with lead. This is of particular concern to children due to the impact of lead exposure on cognitive development and as such these findings have received much media attention. The response from legislators has been swift, and The Victorian School Building Authority has announced that all new schools and school upgrade works will only use lead-free tapware and piping systems. However, while the immediate replacement of lead-containing brass fittings may seem a logical and obvious response, it does not consider the potential implications on microbial contamination. This is particularly concerning given the increasing public health threat posed by opportunistic premise plumbing pathogens (OPPPs). This commentary explores this public health risk of lead exposure from plumbing materials compared to the potential public health risks from OPPPs. Non-tuberculous mycobacterium was chosen as the example OPPP, and the influence on plumbing material and its public health burden in Australia is explored. This commentary highlights the need for future research into the influence of plumbing material on OPPPs prior to any changes in legislation regarding plumbing material.

Sequential drinking water sampling as a tool for evaluating lead in flint, Michigan

Eliminating the sources of human lead exposure is an ongoing public health goal. Identifying the make-up of household plumbing and service line material type is important for many reasons including understanding lead release sources and mechanisms, targeting locations for lead service line (LSL) removal, and assessing the effectiveness of lead remediation strategies. As part of the response to Flint, Michigan's drinking water lead public health crisis, a return to their original drinking water source (Lake Huron) and an increase in orthophosphate dose was implemented in late 2015. In 2016, EPA performed multiple rounds of sequential or “profiling” water sampling to evaluate corrosion control effectiveness and identify lead sources in homes and service lines, as well as to evaluate the effectiveness of corrosion control treatment with time on the different plumbing components. The results showed that lead levels, including high lead levels likely associated with particles, decreased with time in homes sampled during the 11-month evaluation period. Although sequential sampling indicated that brass fittings, brass fixtures, and galvanized pipes were lead sources, LSLs were the greatest source of lead when present. Following the removal of LSLs, the total mass of lead contributed to the drinking water decreased by 86% on average.

Incidence of heavy metals in Kano metropolis drinking water sources

Contamination of Kano metropolis drinking water sources with excessive heavy metals was evaluated using standard laboratory procedures. A total of 72 samples comprising of 24 each of Borehole, Tap and Well water from 8 municipal LGAs (namely; Dala, Fagge, Gwale, Kano municipal, Kumbotso, Nassarawa, Tarauni and Ungogo) were analyzed for the presence of heavy metals (viz; Chromium, Iron, Lead and Zinc). Chromium and Lead concentrations for the samples evaluated (Borehole, Tap and Well) were found to exceed the World Health Organizations (WHO) limits of 0.05 and 0.01mg/l respectively which might be attributed to corrosion of brass fittings of certain submersible pumps and pipes used in borehole and taps specifically. The contamination of well with heavy metals might be due to seepage of sewage into these sources as domestic sewage might be of kitchen and toilet origin heavily accumulated with soaps of heavy metals constituents. Heavy metal contamination with Chromium and Lead calls for serious public health implications for the effects of heavy metals contamination in drinking water.Keywords: Drinking water, Kano, Chromium, Lead, Iron and Zinc

Flintlock brass fittings from the 19th-century Akko 1 shipwreck, Israel

The Akko 1 shipwreck is the remains of a 26-metre-long Egyptian armed vessel or auxiliary naval brig built at the beginning of the 19th century. Remains of six flintlock muskets were retrieved from the shipwreck, and characterised by various metallurgical methods. The research aimed to study the composition and microstructure of the musket fittings and their manufacturing processes, and if possible, to determine the date and origin of the raw materials. The lead isotope analysis of the fittings suggests that their raw material originated in Great Britain. Based on their typology and composition, the fittings were made in Great Britain of brass alloy and manufactured by casting, probably at the same workshop; and the staple was manufactured by casting and drawing. Considering the zinc content, combined with the manufacturing techniques, the fittings were manufactured between the latter part of the 18th and the early 19th centuries, which might indicate that they were purchased in the course of 19th century weapons trade to be used on board the Egyptian ship.

황동이음쇠형 금속플렉시블호스(CSST)의 저항 특성 및 소손 패턴 해석에 관한 연구

황동이음쇠형 금속플렉시블호스(CSST)의 저항 특성 및 소손 패턴 해석에 관한 연구

Evaluation of Lead Release in a Simulated Lead-Free Premise Plumbing System Using a Sequential Sampling Approach.

In this pilot study, a modified sampling protocol was evaluated for the detection of lead contamination and locating the source of lead release in a simulated premise plumbing system with one-, three- and seven-day stagnation for a total period of 475 days. Copper pipes, stainless steel taps and brass fittings were used to assemble the “lead-free” system. Sequential sampling using 100 mL was used to detect lead contamination while that using 50 mL was used to locate the lead source. Elevated lead levels, far exceeding the World Health Organization (WHO) guideline value of 10 µg·L−1, persisted for as long as five months in the system. “Lead-free” brass fittings were identified as the source of lead contamination. Physical disturbances, such as renovation works, could cause short-term spikes in lead release. Orthophosphate was able to suppress total lead levels below 10 µg·L−1, but caused “blue water” problems. When orthophosphate addition was ceased, total lead levels began to spike within one week, implying that a continuous supply of orthophosphate was required to control total lead levels. Occasional total lead spikes were observed in one-day stagnation samples throughout the course of the experiments.

A novel approach to improving resistance to dezincification of diphasic brass

Dezincification-resistant brasses have been developed and refined for nearly 100 years, and lead (Pb) doped brass fittings have played a large role in the transport of potable water. However, due to Pb toxicity, restrictions have been placed on the amount of Pb that can be added to brass, and in general there is no safe level of Pb. In this study, 0.02 wt.% addition of Niobium (Nb) to diphasic brass (also know as duplex brass) was found to significantly improve resistance to dezincification when compared with a 0.20 wt.% doping level of Pb. Nb prevents dezincification in two ways: by alloying with β-phase to suppress the preferential dissolution of Zn and by forming a passivation layer incorporated with Nb that serves as a barrier against chloride ions in CuCl2 solution. As a result, it is expected that a Nb-doped diphasic brass will not negatively impact industrial application of duplex brass.

Impact of Dust from Ore Processing Facilities on Rain Water Collection Tanks in a Tropical Environment—The Obvious Source “Ain’t Necessarily So”

Concerns have been expressed that dust from the minerals processing facilities at Karumba Queensland Australia have resulted in elevated lead (Pb) concentrations in rain water tanks. The ores derived from the Century mine some 304 km from the port. High precision Pb isotopic measurements on environmental samples have been undertaken to evaluate the source of Pb in rainwaters and acid digests from roof wipes and gutter wipes. There does not appear to be any relationship between sample location and the processing facility but samples from the area subject to the prevailing winds show the highest contribution of Century Pb. All gutter wipes (82 to 1270 µg Pb/wipe) have contributions of Century ore ranging from 87% to 96%. The contribution of Century ore to five roof wipes (22 to 88 µg Pb/wipe) ranges from 89% to 97% and in the other two samples there is a mix of Century and Broken Hill Pb. Three of the seven rainwater have contributions of Century ore Pb ranging from 33% to 75%. Two of the other four rainwater samples have the highest water Pb concentrations of 88 and 100 µg/L and their isotopic data show Broken Hill Pb contributions ranging from 77% to 80%. The source of the Broken Hill Pb is probably from the galvanized roofing material and/or brass fittings in the rainwater tanks. The discrimination between various sources is only detectable using high precision 204Pb-based isotopic ratios and not the now common inductively coupled plasma mass spectrometry (ICP-MS ) data presentations of the higher abundance isotopes 208Pb, 207Pb and 206Pb. Isotopic results for the waters demonstrate that apportioning blame where there is an obvious point source may not always be the correct conclusion. Nevertheless the isotopic data for the gutter wipes indicates that there was widespread contamination from the processing facilities throughout the town.

Fountain Autopsy to Determine Lead Occurrence in Drinking Water

Exposure to lead in drinking water poses a risk for various adverse health effects, and significant efforts have been made to monitor and eliminate lead exposure in drinking water. This study focused on the localization of lead exposure from 71 drinking water fountains in nonresidential buildings in order to determine the source of elevated lead and understand the effects of fountains associated with lead concentration in drinking water. Drinking water fountains containing lead-lined cooling tanks and brass fittings were found to release lead concentrations in excess of 10 μg/L, and fountains with low or infrequent usage and those with cooling tanks produced the highest concentrations (in excess of 20 μg/L) of lead. One particular fountain model found at several locations throughout the institution was associated with some of the highest lead concentrations measured throughout the study. This fountain was recalled in the United States, but not in Canada. This article adds to existing research demonstrating that drinking water fountains are a potentially significant and underappreciated source of lead exposure in nonresidential buildings.

Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO4 2- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9–10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

Surface degradation of nickel-plated brass fittings

Since many years, brass has been used in many engineering applications given its low production cost, fairly simple manufacture routes and acceptable corrosion resistance. Brass of many different chemical compositions can be found in complex engineering devices such as turbines and bearings or in ornamental and housing applications from which, the fabrication of fittings and connections for plumbing purposes are the most common. In this work, the surface degradation of nickel-plated brass fittings designed for ornamental plumbing purposes was studied using optical and scanning electron microscopy together with energy dispersive and X-ray diffraction analyses. It was found that this phenomenon was caused by the formation of zinc and copper oxides at the metal-coating interface and that reached the surface by means of growing through cracks that were also formed in the nickel coating. The occurrence of these defects is explained in terms of the cleanness of both, the brass specimens and the electrolytic solution used for plating.

Forensic Engineering Investigation Of Dezincification In A Major Corrosion Litigation

Zinc-Rich Brasses With The Zinc Content Above 30% Can Be Involved In Corrosion Processes With Catastrophic Results. The Dezincification Results In A Low Strength Copper With A Porous Sponge Like Structure. The Case, Where Dezincification Occurred With Massive Impact, Involved 34,000 New Homes In An Urban Location In Nevada. These Homes Were Constructed Using Building Code Approved Plastic Pex Tubing For Plumbing With Brass Fittings. Leaks Developed In The Home Plumbing Systems After Approximately 3-6 Years. This Failure Resulted In Lawsuits Involving Home Owner Associations, Insurance Companies, Contractors, Plumbers, Architects, Manufacturers, And Suppliers.

Secondary effects of implementing arsenic removal treatment—focus on corrosion and microbial regrowth

Strong‐base anion exchange, activated alumina, and granular ferric hydroxide/oxide media are technologies that small utilities will be using for arsenic removal to meet the new standards imposed by the US Environmental Protection Agency Arsenic Rule. Under at least some circumstances, however, these treatments can be predicted to cause severe adverse consequences. The removal of natural organic matter by column treatments can lead to an increase in copper pitting. Lower levels of bicarbonate in conjunction with higher concentrations of chloride can increase iron corrosion and cause red water complaints. Higher chloride‐to‐sulfate mass ratios can increase lead release from brass fittings and solder. Conversely, column treatments may remove phosphate or other trace inorganics creating nutrient limitations, which could reduce the potential for microbial regrowth in the distribution system.

Microbiologically influenced corrosion in hydronic heating systems

Open-loop hydronic heating systems have been found to provide a breeding ground for bacteria, including bacteria associated with microbiologically influenced corrosion (MIC). Microbiologically influenced corrosion of brass fittings, which may contain up to 8% lead in potable water applications, has been linked to high copper and lead levels in water samples taken from the hydronic-loop tubing. The contamination is likely concentrated in slime deposits found within the tubing. These slime deposits can enter the potable water supply, resulting in potential copper and lead exposure levels considerably above Environmental Protection Agency (EPA) guidelines. The authors recommend that hydronic heating systems incorporate a closed-loop design to prevent personal exposure and to provide for use of corrosion-inhibiting additives.