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My family received a request through the community app (NextDoor) asking if we would like to test our water for lead. This makes me think.
Lead is highly toxic. For children, the Environmental Protection Agency and the Centers for Disease Control and Prevention agree that there is no safe blood lead level.
Lead should not be present in drinking water. Even if the concentration is moderate, lead can cause various symptoms and diseases in children and adults. The impact of lead in drinking water on entire communities has become news headlines around the world.
Lead is a naturally occurring element with very little content in the earth's crust. Although it has some beneficial uses, it may be toxic to humans and animals and cause health effects.
Long-term intake of small amounts of lead or short-term intake of large amounts of lead may cause lead poisoning. Lead poisoning is a common disease. 1 There may be terrible symptoms or no symptoms at all until it is too late. 2 It is even implicated in the decline of the Roman Empire. 3 Mitigating the health effects of lead may be a long or even impossible process.
The impact of lead poisoning on children and adults
The impact on the growth and development of children may be terrible. According to a paper by the peer-reviewed medical journal American Family Doctor, an estimated 500,000 American children were lead poisoned in 2017. A 2020 report in the peer-reviewed medical journal The Lancet estimates that 815 million children worldwide have high blood lead levels. The following list of symptoms for children is not intended to classify all possible health effects of lead; instead, it is intended to show you the most significant health effects related to lead in drinking water:
Lead poisoning in adults can cause:
Lead can enter our body in many ways, whether intentionally or unintentionally. Lead paint has a sweet taste that can attract children to eat paint chips. Lead can also be accidentally inhaled from contaminated soil, household dust, and when lead-containing paint degrades into tiny pieces and flakes that can spread in the air. In 1978, the United States banned the sale and use of lead paint. Lead may also enter your body when using certain traditional treatments or cosmetics, contacting battery waste or solder (fusible metal), handling tin or artificial jewelry, using some pottery and cooking utensils, eating food stored in soldered pots, Engage in an occupation that uses lead (such as radiology or fetal monitoring), or playing with antiques or foreign-made toys. 4,6 One of the most insidious and common ways is through domestic water supply-drinking water.
According to the U.S. Environmental Protection Agency, “When plumbing materials containing lead corrode, lead enters the drinking water, especially when the water’s acidity is high or the mineral content is low, it will corrode pipes and fixtures. Common sources of lead are lead pipes, faucets, and fixtures. In households that use lead pipes to connect houses to water pipes (also called service lines), these pipes are usually the most important source of lead in the water. Built before 1986 Lead pipes are easier to find in old towns and houses. In households without lead service lines, the most common problems are brass or chrome-plated brass faucets and plumbing with lead solder."
Lead in drinking water usually does not come from the water source, but is inadvertently added to the water during transportation to the point of use (POU). Until the mid-1900s, U.S. cities used lead as the main means of household water supply pipes.
Lead in water is not just an urban problem. Lead can be added to the water through the old lead water main, the lead service line that enters the house from the main utility supply line, through the lead pipe in the old house, the solder joint of the copper pipe made before 1986, or using the old 50:50 (Pb-tin) solder on pipes, old brass fittings in the house, new brass fittings that are not certified as lead-free, and solder joints in water heaters.
Most of the lead may come from main pipes and service pipes, but due to lead solder and brass in the home, a large number of cases of lead poisoning have been recorded. Qualified plumbers will only use lead-free fittings. You should be cautious when ordering pipe fittings from online channels, which may distribute fittings from countries with less stringent standards.
You can tell if your service lines are made of copper, steel, or lead by checking where they enter your house. The copper pipe will be copper-colored, just like the old penny. Silver or gray pipes can be steel or lead. If they are lead, you can use a coin to make a deep scratch on them. Even if you don't have lead pipes to enter your house, the main supply lines under the street may be made of lead, unless your area has been laying utility lines under the street since around 1986. A self-help tool is available from the National Public Radio. This shows you how to determine if your plumbing contains lead. If you find lead pipes, your drinking water may contain lead.
If you do not find obvious lead pipes, your drinking water may still contain lead, which comes from the water mains, which are pipes outside the walls of the house or pipe fittings inside the house. The median age of houses in Minnesota is 43 years. This means that half of the houses in Minnesota were built before 1978 and the other half were built after 1978. It was not until 1986 that lead-tin solder was banned for use in plumbing houses.
Half of the houses in Lac qui Parle County were built before 1951, Huangyao County before 1957, St. Louis County before 1962, Ramsey County before 1965, Lake County before 1970, and Hennepin County before 1972. Cook County before 1985. People in Minnesota have a better chance of containing some lead in their drinking water than 50:50.
If you live in a town where utility lines have been installed since 1990, and new houses built since 1990 are filled with plastic pipes, you may not have a large source of lead in your drinking water system. If your town or house is older, it is difficult to guess. Because the presence of lead will affect the health of our family, it is definitely better to know whether your home has lead than to guess. Fortunately, there are some simple ways to test your water quality.
Reliable testing of lead in water is very difficult because the concentration of interest is in the range of 10 parts per billion (think about 1 cent in a million dollars), and lead exists in the form of dissolved lead and particles in the water . The Minnesota Department of Health (MDH) checks the quality and accuracy of lead testing performed by Minnesota laboratories and maintains a list of accredited water testing laboratories (see also this link to find laboratories). To be reliable, these tests are performed by qualified personnel who have performed hundreds of tests using expensive equipment and clean, properly equipped laboratories. To ensure reliable results, these laboratories perform extensive quality assurance and quality control, and must pass regular state or federal certification tests.
The following table lists the MDH accredited laboratories in Minnesota. They will provide drinking water lead testing for residential customers in September 2021. They will answer my phone or email and provide clear information. There may be other companies that provide lead testing, but if you find one, please make sure they are MDH certified for lead testing in drinking water. The laboratories listed below do not imply endorsement or recommendation by me or Minnesota Sea Grant.
AW Research Laboratories Inc
The bottle can be mailed or picked up at the office;
Pick up the kit from them because they are preserved with nitric acid (they don’t ship it)
Pick up the container or deliver it at a nominal fee
Minnesota Valley Testing Laboratories Inc
Minneapolis, Minnesota and other locations
Don’t do a separate lead test, but do a $250 all-metal panel
Bloomington, Minnesota; Lake Detroit, Minnesota; Hibbing, Minnesota
Southeastern Minnesota Water Analysis Laboratory (Olmsted County)
Pick up materials in Rochester, Minnesota
The company responds to the sampling procedure pdf and quotation
Twin City Water Clinic, Inc.
Supply sample vials and instructions
Laboratory supplies bottles and instructions; price not announced
The company supplies sample bottles and instructions
Generally speaking, the lead testing process is very simple and easy. You pick up the sampling bottles from the laboratory, or the laboratory mails them to you with instructions on how to collect water samples.
Sampling is designed to represent the worst-case scenario, so it is important to sample from a tap that is undisturbed for as long as possible (for example, overnight). If you take a sample from a faucet or faucet that is allowed to operate, you can reduce any possible lead by flushing.
The sample bottle is then sealed and sent back or brought back to the laboratory for analysis. Usually, the results are sent back to the customer within a few days and contain information on how to interpret the analysis. In the past, the EPA mandated that community water systems take action to reduce the lead content to 15 parts per billion (0.015 milligrams per liter or mg/L). Recently, the trigger level has been revised to 10 parts per million (0.01 milligrams per liter or mg/L), but it should be noted that there is no safe level of lead in drinking water.
How about do-it-yourself (DIY) testing? If you shop online, you will find many lead detection kits for domestic drinking water. Advertisements will say things like "methods approved by the EPA are verified to be accurate", "tested by an EPA expert team" or "have EPA or WHO standard records." Because lead is a powerful poison, I suggest that you and your family should be analyzed by a certified laboratory.
If you find lead in your drinking water supply, the ultimate way to fix it is to replace all leaded pipes and fittings, service lines, and mains in your home. The water main is the responsibility of the water company, but the part of the water pipe that passes through the homeowner’s property into the house is usually the homeowner’s responsibility. All plumbing and fixtures in the home are of course the responsibility of the owner. Replacing water pipes and pipelines belonging to public utilities is an expensive and long-term task that requires a large amount of investment tax and is unlikely to be resolved in the short term. It is also expensive to replace the owner’s service pipeline, requiring the excavation of the old pipeline and the replacement of the pipeline under the owner’s property. It is also expensive and requires the hiring of a licensed contractor. The replacement of pipes, water heaters and fittings connected to the drinking water supply in the house is best done by a licensed plumber. Some small jobs can be DIY, especially the installation of PEX (cross-linked polyethylene) pipes and fittings (PEX pipes are free of lead). All accessories should be lead-free certified by the appropriate certification body. EPA provides a quick guide for identifying the appropriate certification marks for accessories connected to drinking water supplies.
Here are some options for removing lead.
bottle. You can buy commercial bottled water, but the cost of bottled water is on average 2,000 times that of tap water and 1,000 times that of household filtered water.
furnish. Removing all lead from the water supply is the best way to avoid lead exposure, but this can be expensive and time-consuming.
filter. There are a variety of techniques that can be used to reduce the lead content in drinking water.
The National Sanitation Foundation (NSF) and the American National Standards Institute (ANSI) are testing standards designed to help protect the safety of consumers by ensuring the efficacy of finished products. NSF is a non-profit organization that develops public health standards and certification programs that help protect the world's food, water, consumer products, and environment. ANSI is a non-profit organization whose role is to promote and promote voluntary consensus standards and conformity assessment systems and maintain their integrity. ANSI and NSF collaborate to establish and coordinate public health, safety, and environmental standards.
If you are not familiar with the details of NSF-ANSI Standard 53, then you are not alone! I spent $165 and two hours to unlock the security protection on the ANSI website to be able to view Standard 53. What surprises me is that for American consumers, something as important as a set of public standards for maintaining health will be locked in a non-profit organization’s paywall. There have been talks within the government about ensuring open access to scientific information, which seems out of place, especially because federal agencies recommend only purchasing equipment that meets these standards.
This standard is the most important of the two standards (53 and 42) because it sets standards for the removal of hazardous materials. The standard requires every filtration system to "challenge" by using a high-lead water source similar to tap water and operating at a household usage rate. The test water contains approximately 150 ppm of soluble lead, and the filter must reduce it to a maximum effluent concentration of 5 ppm. This represents a reduction of at least about 97%. But remember, there is no safe lead in drinking water.
Since lead particles are more common in water with a high pH (8.5 or quite high household water pH), particulate filters must also be tested to ensure that they can remove lead particles as small as 0.1 microns (than most bacteria Small; about one thousandth of the thickness of a sheet of paper). The test was run multiple times and simulated household water and temperatures close to room temperature during the on-off cycle.
Tests like this run on all types of filters, including POE, POU, pitchers, drinking water bottles, and refrigerator filters. For piping systems, at the end of the rated gallon capacity, the flow through the filter must not be reduced by more than 25%, otherwise it cannot be claimed to meet this standard. Therefore, all water filters that meet standard 53 will remove at least 97% of the lead in the water. These filters can also remove many other unwanted substances, including particles, chlorine, odors, other metals (such as arsenic, etc.), pathogenic organisms, some organic chemicals, and other substances you want to avoid.
Choosing the right method to remove lead from your home requires you to decide a few things.
First of all, you want to be able to extract lead-free water from where in your home. If it can be easily installed on a single tap (for example, in your kitchen), this will simplify the problem and reduce disposal costs.
Second, how much water do you want to filter? This is important because all water filtration systems have a specific filtration capacity, and the system will stop working until a new filter element is installed. To determine the flow rate of one or more taps to be used for drinking water, use the stopwatch function on your smartphone to measure the time it takes to fill a one-gallon container. This should be done when there is no other water flow in the house.
When you choose a filter system, this simple math will help you calculate the cost and trouble of buying and installing filter elements
The next step is to check the list of manufacturers that provide filtration systems that meet NSF Standard 53 (see the list of NSF POU systems here). These include piping systems that work with individual faucets or existing piping, systems installed on faucets, countertop devices connected to faucets, water bottle or water bottle filters, and more complex reverse osmosis systems. The list is quite extensive, so it may take some time to browse through it. It handles all types of filters. You may be familiar with some of these companies, but others may be unfamiliar. Most list the amount of water that each filter can handle. You can use it as a guide to find the cost of replacing filters online or elsewhere, so you can judge availability and cost.
cost. Dividing the cost of each filter by the volume listed will tell you how much it costs per volume to remove lead. The filter installed under my sink costs about $165, but it can safely handle 6,000 gallons. I have a pitcher unit with a much cheaper filter ($9), but it can only handle 40 gallons before replacement. The operating cost of the device under the sink is less than one tenth of that of the sink filter.
Make sure that no matter what you buy, you can obtain or request the NSF performance data sheet of your model before buying. This will show you the results of various tests and the extent to which the product meets the standard. For lead and other pollutants, it usually tells you the concentration of influent (water flowing into the device), the average reduction rate (usually a percentage), and the allowable concentration in the outflow water (water flowing out of the device). Requesting performance data sheets is part of being an informed and responsible consumer.
No matter which NSF standard 53 certified water filter you use, it will not work if you do not follow the manufacturer's instructions. These are not just suggestions. They are the conditions for the filter to meet the test requirements. If you fail to follow the instructions, you may not be able to remove lead. Some specifications relate to acceptable water temperature and pressure, maximum flow rate (standard 53 is set to 2.5 gallons per minute), and the maximum number of gallons that can effectively pass through the filter. Pitcher filters are particularly difficult to monitor, because the indicator light usually only counts for a period of time, not the amount of water filtered. Although some in-line filters use a system that shuts off the water when the maximum gallons are filtered, I added a $30 digital meter, available from an online retailer, which tells me when enough water has passed through the filter Expel it.
A recent test10 of POU filters has shown that even certified filters can fail in several situations. The most important factor is whether the lead is dissolved in water or suspended in particulate form. Where lead content is very high (ie >1000 ppb; for example, Flint, Michigan 11 and Newark, New Jersey 12), compared to the standard 53 ANSI-NSF challenge (test), more lead is particulate The form moves. POU filters cannot filter particles like dissolved lead. Some of these lead-containing particles are very small, which means that it is advisable to choose a filter to remove particles of 0.2 microns or smaller, and the effect will be better. Other challenges of POU equipment include very slow filtration and flow rates, leaks and physical failures, inconsistent functions between repeated equipment, and manufacturing defects.
If you live in a house with a lot of old iron pipes, or your neighbors are older, adding a simple particle filter ($20-50) between the water inlet and the lead filter system is a good preventive measure . If your water or nearby water is closed for maintenance and then reopened, it is very likely that a large amount of rust particles will enter your water supply system. These relatively inexpensive particulate filters can capture rust and lead filings before they enter the more expensive lead filters. If you do not have or install a particulate filter and your water is turned off, make sure to drain all rust from the system in another sink without a lead filter before passing any water through the lead filter.
It should be emphasized that all certified lead filters can remove large amounts of lead in drinking water. They work better at moderate to low lead content (for example, less than 150 ppm), when most lead is soluble, and when operated within the manufacturer's operating specifications. One way to determine if your filtration system is working properly is to use one of the laboratories listed above to test the water passing through the filter.
Protecting our families, especially our children, from lead in drinking water can be costly. Testing the lead content of household water can cost $18 to $250. It may cost more than $1,000 to replace the main service line to the house. Installing filtration or reverse osmosis equipment to remove lead may cost 30 to 1,000 US dollars or more. Regular replacement of lead water filters may cost 14 to 300 US dollars or more.
We and many of our neighbors may not be able to obtain most of these remedies financially. In ancient Rome, because they were the only people who owned (lead) pipes, they were wealthy people affected by lead poisoning. 3 In contrast, today, poor communities are disproportionately affected due to high lead concentrations in drinking water. 13 If you have the ability to test and treat your water, please consider helping your unfortunate neighbors or community members. By helping each other, we can make our water world safer for everyone.
1 Barltrop, D. in Poisoning Diagnosis and Treatment (eds JA Vale & TJ Meredith) 178-185 (Springer Holland, 1981).
2 Waldron, HA Subclinical lead poisoning: a preventable disease. Preventive Medicine 4, 135-153 (1975).
3 Needleman, L. and Needleman, D. Lead poisoning and the decline of Roman nobility. Echos du monde classique: Classical View 24, 63-94 (1985).
4 Bhowmik, D., Kumar, KPS & Umadevi, M. Lead poisoning-the future of lead’s impact on our society. Pharmaceutical Innovation 1, 40-49 (2012).
5 WHO. Lead poisoning and health, <https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health> (2019).
6 Debnath, B., Singh, W. & Manna, K. The source and toxicological effects of lead on human health. Indian Professional Journal of Medicine 10, 66-71, doi:10.4103/injms.Injms_30_18 (2019).
7 Duo Lei, E. et al. Effectiveness of using point filters and water tank filters to remove lead phosphate nanoparticles from drinking water. Water Research 201, 117285, doi: https://doi.org/10.1016/j.watres.2021.117285 (2021).
8 NSF International. 164 (NSF International, Ann Arbor, Michigan, USA, 2019).
9 Kim, EJ, Herrera, JE, Huggins, D., Braam, J. & Koshowski, S. The effect of pH on the concentration of lead and trace contaminants in drinking water: a study of combined batches, pipeline circuits, and sentinel households. Water Research 45, 2763-2774, doi: https://doi.org/10.1016/j.watres.2011.02.023 (2011).
10 Purchase, JM, Rouillier, R., Pieper, KJ & Edwards, M. Understand the failure modes of NSF/ANSI 53 lead certification point taps and tap filters. Environmental Science and Technology Letter 8, 155-160, doi: 10.1021/acs.estlett.0c00709 (2021).
11 Bosscher, V., Lytle, DA, Schock, MR, Porter, A. & Del Toral, M. POU Water filters effectively reduce lead in drinking water: a demonstration field study conducted in Flint, Michigan. Journal of Environmental Science and Health, Part A 54, 484-493, doi: 10.1080/10934529.2019.1611141 (2019).
12 Lytle, DA and others. Grading and identification of lead in drinking water in Newark, New Jersey. Environmental Science and Technology 54, 13672-13679, doi: 10.1021/acs.est.0c03797 (2020).
13 Hanna-Attisha, M., LaChance, J., Sadler, RC, and Champney Schnepp, A. Elevated blood lead levels in children associated with the Flint drinking water crisis: a spatial analysis of risks and public health responses. American Journal of Public Health 106, 283-290, doi:10.2105/AJPH.2015.303003 (2015).
List of NSF certified products used to reduce lead
University of Minnesota's System-wide Program
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